METHODS: Patients were randomly assigned to receive saline (n = 38) or a modified full-dose regimen of aprotinin (n = 37) IV during OPCAB surgery. Blood sampled perioperatively from the coronary sinus, skin wounds, and systemic circulation was analyzed to test coagulation and platelet function. Major adverse cardiovascular events were monitored by obtaining troponin I at 24 h (myocardial infarction), predischarge computed tomography angiography (vein graft thrombosis), and by clinical examination for stroke.

RESULTS: Coronary sinus blood obtained immediately after OPCAB surgery showed significantly less activation in the aprotinin group, as judged by reduced formation of platelet-leukocyte conjugates (P < 0.02) and platelet-derived microparticles (P < 0.05). The aprotinin group showed inhibition of platelet aggregation induced by thrombin (P = 0.007) but not adenosine diphosphate. Thrombin generation, defined by F1.2 levels, was significantly reduced by aprotinin in the coronary sinus but not in skin wound incisions. Major adverse cardiovascular events were significantly reduced in aprotinin-treated patients (5.4% vs 29.7%, P < 0.05). Aprotinin also demonstrated antifibrinolytic properties through diminished red blood cell transfusion (P < 0.04) and reduced blood loss postoperatively (603 ± 330 vs 810 ± 415 mL, P < 0.004).

CONCLUSION: This study demonstrates that aprotinin protects patients undergoing OPCAB surgery from a hypercoagulable state by diminishing thrombin-induced platelet activation and thrombin generation within saphenous vein grafts, while maintaining systemic hemostatic and antifibrinolytic benefits. These results support further investigation of aprotinin and other PAR-1 antagonists in OPCAB surgery.

METHODS: After surgical instrumentation, we divided male Sprague-Dawley rats into 3 sets. The first set was divided into groups, which received methadone (0.03–3 mg/kg), morphine (0.03–3 mg/kg), or water (placebo) 30 min before ischemia. Some animals of the first set also received the -opioid antagonist naltrindole (5 mg/kg) before methadone (0.3 mg/kg), morphine (0.3 mg/kg), or placebo administration. The second set of animals was divided into groups that received methadone (0.3 mg/kg) 5 min before reperfusion or 10 s after reperfusion. These 2 sets of animals were subjected to 30 min of myocardial ischemia by left anterior descending coronary artery occlusion and then 2 h of reperfusion. The third set of animals received placebo, methadone (0.3 mg/kg), or morphine (0.3 mg/kg) 5 min before reperfusion and were subjected to 45 min of ischemia by left anterior descending coronary artery occlusion with 2 h of reperfusion. Myocardial IS was assessed by staining myocardial tissue with triphenyltetrazolium chloride and expressed as a percentage of the area at risk (mean ± sem).

RESULTS: Methadone or morphine administered before ischemia reduced myocardial IS. The greatest effect was achieved at a dose of 0.3 mg/kg (methadone, 46% ± 1%, P < 0.001 and morphine, 47% ± 1%, P < 0.001 versus placebo, 61% ± 1%, respectively). Naltrindole (5 mg/kg) blocked methadone-induced (0.3 mg/kg) and morphine-induced (0.3 mg/kg) cardioprotection (naltrindole + methadone, 58% ± 1%, P < 0.001 versus methadone; and naltrindole + morphine, 58 ± 1%, P < 0.001 versus morphine). Methadone (0.3 mg/kg) reduced myocardial IS when given 5 min before reperfusion (46% ± 1%, P < 0.001 versus placebo) but not 10 s after reperfusion (60% ± 1%, P = 0.675 versus placebo). No significant myocardial IS differences were seen for placebo when comparing the 45-min ischemia group (64% ± 1%) with the 30-min ischemia group (60% ± 1%, P = 0.069). The longer ischemia time of 45 min abrogated methadone-induced IS reduction (64% ± 2%, P = 0.867 versus 45-min ischemia placebo group) and morphine-induced IS reduction (65% ± 1%, P = 0.836 versus 45-min ischemia placebo group).

CONCLUSIONS: These findings demonstrate that methadone and morphine produce similar myocardial IS-sparing effects that are -opioid receptor mediated and that are dependent on the duration of myocardial ischemia.

METHODS: A detailed cardiac history, resting echocardiography, and hemoglobin and NT-proBNP levels were obtained in 666 patients before vascular surgery. Anemia was defined as serum hemoglobin <13 g/dL for men and <12 g/dL for women. Troponin T measurements and 12-lead electrocardiograms were performed on postoperative days 1, 3, 7, and 30 and whenever clinically indicated. The primary end point of the study was the composite of 30-day postoperative cardiovascular death, nonfatal myocardial infarction, and troponin T release. Receiver operating characteristic curve analysis was used to assess the optimal cutoff value of NT-proBNP for the prediction of the composite end point. Multivariable regression analysis was used to assess the additional value of NT-proBNP for the prediction of postoperative cardiac events in nonanemic and anemic patients.

RESULTS: Anemia was present in 206 patients (31%) before surgery. Hemoglobin level was inversely related with the NT-proBNP levels (β coefficient = –2.242; P = 0.025). The optimal predictive cutoff value of NT-proBNP for predicting the composite cardiovascular outcome was 350 pg/mL. After adjustment for clinical cardiac risk factors, both anemia (odds ratio [OR] 1.53; 95% confidence interval [CI]: 1.07–2.99) and increased levels of NT-proBNP (OR 4.09; 95% CI: 2.19–7.64) remained independent predictors for postoperative cardiac events. However, increased levels of NT-proBNP were not predictive for the risk of adverse cardiac events in the subgroup of anemic patients (OR 2.16; 95% CI: 0.90–5.21).

CONCLUSIONS: Both anemia and NT-proBNP are independently associated with an increased risk for postoperative cardiac events in patients undergoing vascular surgery. NT-proBNP has less predictive value in anemic patients.

METHODS: Children (aged 5–15 yr) who underwent general anesthesia were included, and all perioperative data including anesthetic drugs were collected prospectively. Children were interviewed three times postoperatively using a semistructured questionnaire. All cases of possible or probable awareness were discussed with the child's care providers to confirm or refute the memories. Internal consensus among investigators across sites was reached, and these cases and a random selection of others were reviewed by three external reviewers. For the purpose of this study, possible/probable awareness was defined as cases with agreement between the internal consensus and at least two of the three external reviewers.

RESULTS: One thousand seven hundred eighty-four children completed at least one interview. Thirty-two cases were coded as possible or probable awareness by at least one entity (i.e., either the internal consensus or one of the external reviewers). Fourteen of these cases met the definition for possible/probable awareness, making the incidence of awareness 0.8%. Six of the 14 children with awareness (43%) remembered feeling scared during their surgery and three (21%) reported hurting. Two children in this group (14%) said they would feel worse if they had to have surgery again, which was not significantly different from reports of children with no recall (15%). None of the children with awareness required psychological follow-up. Endoscopic procedures were associated with a higher risk for awareness (relative risk = 4.5 [confidence interval 1.5–13.6]).

CONCLUSIONS: Although 0.8% of children experienced possible/probable awareness in this study, none experienced short-term psychological distress.

Our aim in this exploratory study was to first compare BIS values at 4 different stages of anesthesia between intellectually disabled children and controls. Our second aim was to investigate the discriminative properties of BIS between consciousness and unconsciousness for intellectually disabled children and for controls.

METHODS: Eighteen intellectually disabled children and 35 control children, aged 2–13 yr, were included. BIS values, landmark events, and standard monitoring values of vital functions were recorded throughout the whole procedure. The performance of BIS in distinguishing between a conscious and unconscious state was assessed from receiver operating characteristic curves.

RESULTS: Median (interquartile range) BIS values for the intellectually disabled group were significantly lower than those for controls in the awake state (72 [48–77] vs 97 [84–98], P < 0.001), during stable intraoperative anesthesia (34 [21–45] vs 43 [33–52], P = 0.02), and during return of consciousness (59 [36–68] vs 73 [64–78], P = 0.009). The discriminative properties of the BIS monitor for the state of consciousness were comparable between the 2 groups according to the receiver operating characteristic curves. Nevertheless, the optimal cutoff BIS value for discrimination between conscious and unconscious state was 28 points lower for the intellectually disabled group.

CONCLUSIONS: We advise anesthesiologists to be alert to possible lower BIS values in intellectually disabled children. There is a risk that they will inadvertently misinterpret the state of consciousness in intellectually disabled children. New multicenter studies must find the optimal manner of evaluating (un)consciousness in intellectually disabled patients with documented and confirmed specific etiologies of their intellectual disability.

METHOD: Digital audiovisual recordings of 293 children undergoing outpatient elective surgery were coded using Observer XT software and the validated Revised Perioperative Child-Adult Medical Procedure Interaction Scale. Multiple pass second-by-second data recording was used to capture children’s behaviors across phases of anesthesia induction.

RESULTS: More than 40% of children aged 2–10 yr displayed some distress behavior during induction with 17% of these children displaying significant distress and more than 30% of children resisting anesthesiologists during induction. Children’s distress and nondistress behaviors displayed four profiles over the course of anesthesia induction: Acute Distress, Anticipatory Distress, Early Regulating Behaviors, and Engagement with Procedure. Older children had higher scores on early regulating and engagement profiles whereas younger children had higher scores on Acute Distress. There were no differences across age in children’s Anticipatory Distress. Construct validity of behavior profiles was supported via correlations of profile score (overall and on the walk to the operating room) with a validated assessment of children’s anxiety at induction.

CONCLUSIONS: Children undergoing anesthesia display a range of distress and nondistress behaviors. A group of behaviors was identified that, when displayed on the walk to the operating room, is associated with less distress at anesthesia induction. These data provide the first examination of potentially regulating behaviors of children, but more detailed sequential analysis is required to validate specific functions of these behaviors.

METHODS: We included 95 patients who had suffered from postoperative vomiting (POV) after general anesthesia and 94 control patients. After DNA isolation, the entire HTR3A and HTR3B coding regions, the 5' flanking regions, and exon/intron boundaries were screened for genetic variants. Correlation of identified genetic variants with POV was determined by logistic regression.

RESULTS: We identified 16 different variants in the HTR3A gene and 19 in the HTR3B gene. By using a multivariate logistic regression model that also included classical risk factors, the HTR3A variant c1377A>G was associated with a significantly higher risk (odds ratio [OR] 2.972; 95% confidence interval [CI] 1.466–6.021; P = 0.003) and the HTR3B variants c5+201_+202delCA (OR 0.421; 95% CI 0.257–0.69; P = 0.001) and c6-137C>T (OR 0.034; 95% CI 0.003–0.332; P = 0.004) were associated with a lower risk for POV. However, all significant genetic variants were located in noncoding regions of their gene.

CONCLUSIONS: Genetic variations in the HTR3A and HTR3B gene seem to be associated with the individual risk of developing POV. How strong their influence is within the multifactorial genesis of POV needs to be investigated in additional studies with an appropriate sample size.

METHODS: Two hundred adult patients presenting for elective outpatient colonoscopy were randomized to receive propofol alone or propofol plus midazolam, and/or fentanyl for IV sedation. Baseline cognitive function was measured using the computerized CogState test battery (Cogstate^TM, Melbourne, Australia) before sedation. During the procedure, sedative drug doses, depth of sedation (via the bispectral index and observer’s assessment of alertness/sedation score), complications, and treatability were recorded. Patients were interviewed about recall immediately after emerging from sedation, and cognitive testing was repeated at hospital discharge. Recovery times, quality of recovery, and satisfaction with care were also recorded.

RESULTS: In the propofol plus adjuvants group, 84 patients received fentanyl 50 µg (25–100) (median [range]) and 57 patients received midazolam 2 mg (0.5–10). Patients’ cognitive function at discharge was worse than their performance at baseline. However, the changes in cognitive function between discharge and baseline were not significantly different between the two groups. At discharge, 18.5% of patients were cognitively impaired to an extent equivalent to a blood-alcohol concentration of 0.05%. Sedation with propofol plus midazolam and/or fentanyl produced better operating conditions than sedation with propofol alone and was associated with shorter procedure times. Recovery times, recall, dreaming, quality of recovery, and patient satisfaction with care were similar between the groups. Administration of >2 mg of midazolam was a predictor of impaired cognitive function at discharge.

CONCLUSIONS: Significant cognitive impairment was common at discharge from elective outpatient colonoscopy. However, the addition of midazolam and/or fentanyl to propofol sedation did not result in more cognitive impairment than the use of propofol alone. Furthermore, the use of adjuvants improved the ease of colonoscopy without increasing the rate of complications or prolonging early recovery times..

METHODS: In this double-blind study, 52 healthy women scheduled to undergo tubal sterilization were randomly assigned to receive either intrathecal 10 mg lidocaine 2% plus 10 µg fentanyl (Group I) or intrathecal 3 mg levobupivacaine 0.5% plus 10 µg fentanyl (Group II), each solution made to a total volume of 3 mL with sterile water. The following variables were monitored intraoperatively: anesthesia onset time, need for anesthesia-analgesia supplementation, depth of sedation, surgical conditions, and occurrence of hemodynamic events. After surgery, motor block, proprioception, vibration sense, light touch, and Romberg’s test were performed to evaluate whether the patients could bypass the postanesthesia care unit and be allowed to walk by themselves. Sensory block level was determined at 5, 10, and 15 min after anesthetic injection, and then every 15 min until resolution was complete. A difference of 25 min in sensory block resolution time was considered clinically relevant.

RESULTS: Onset time and intraoperative conditions were comparable in both groups. No patient required general anesthesia to complete surgery. All patients from both groups bypassed the postanesthesia care unit. Ambulation took place after 27 (18–45) min in Group I and 30 (18–56) min in Group II (P = 0.24). Complete regression of spinal anesthesia occurred after 93 (65–120) min in Group I and 105 (78–150) min in Group II (P = 0.019); however, no differences were observed in time for home discharge 185 (150–300) min in Group I and 188 (125–300) min in Group II (P = 0.62). Global patient satisfaction was comparable between both groups.

CONCLUSIONS: Levobupivacaine 3 mg plus 10 µg fentanyl may be used as a suitable alternative to 10 mg lidocaine plus 10 µg fentanyl for spinal anesthesia of short duration. It achieved a clinically equivalent time for resolution of sensory block, similar intraoperative conditions, and comparable patient satisfaction..

METHODS: Sixty-five female patients (ASA physical status I–II) scheduled for transabdominal hysterectomy were recruited to this randomized, placebo-controlled study. Thirty-two patients in the treatment group received IV lidocaine starting 20 min before surgery, whereas the control group (33 patients) received a matched saline infusion. Both groups received patient-controlled epidural analgesia during the postoperative period. Blood samples were collected before, 24, 48, and 72 h after surgery to measure ex vivo cytokine production of interleukin (IL)-1 receptor antagonist (IL-1ra) and IL-6, as well lymphocyte mitogenic response to phytohemagglutinin-M. A 10-cm visual analog scale was used to assess pain intensity at rest and after coughing.

RESULTS: Patients in the lidocaine + patient-controlled epidural analgesia group experienced less severe postoperative pain in the first 4 and 8 h after surgery (visual analog scale 4/3.7 at rest and 5.3/5 during coughing versus 4.5/4.2 and 6.1/5.3, respectively, in the placebo group). There was significantly less ex vivo production of IL-1ra and IL-6, whereas the lymphocyte proliferation response to phytohemagglutinin-M was better maintained than in the control group.

CONCLUSION: The present findings indicate that preoperative and intraoperative IV lidocaine improves immediate postoperative pain management and reduces surgery-induced immune alterations.

METHODS: Data from 45 patients scheduled for a radical prostatectomy were analyzed. After lumbar epidural catheterization, patients received remifentanil and propofol solely for induction of anesthesia. Thereafter, epidural analgesia was initiated, and isoflurane, sevoflurane, or desflurane (15 patients each) was added to maintain unconsciousness. At least 45 min later, end-tidal concentrations were varied between 0.5 and 2 minimum alveolar anesthetic concentration. We estimated an individual k_e0 value for each patient by optimizing the prediction probability P_K (P_K-based k_e0) or by minimizing the area within the hysteresis loop (area-based k_e0). Data are mean ± sd.

RESULTS: Both semiparametric approaches led to comparable k_e0 values with 0.18 ± 0.06 min^–1 (P_K based) and 0.15 ± 0.04 min^–1 (area based) for isoflurane and 0.17 ± 0.08 min^–1 (P_K based) and 0.16 ± 0.11 min^–1 (area based) for sevoflurane. k_e0 values for desflurane (P_K based: 0.30 ± 0.17min^–1; area based: 0.32 ± 0.25 min^–1) were significantly higher than for isoflurane and sevoflurane.

CONCLUSION: Maximizing the prediction probability P_K for estimating k_e0 seems to be a promising method that researchers could use on an exploratory basis.

METHODS: We first examined changes in blood glucose levels in rats undergoing sigmoid colostomy under sevoflurane, sevoflurane/buprenorphine, propofol, and propofol/buprenorphine anesthesia. We then examined changes in blood glucose levels after glucose administration using awake rats, rats under sevoflurane anesthesia, and rats under propofol anesthesia.

RESULTS: Blood glucose levels increased markedly after sigmoid colostomy under sevoflurane anesthesia; the marked increases could not be prevented by the coadministration of buprenorphine. Under propofol anesthesia, blood glucose levels did not change after sigmoid colostomy at the highest dose, but increased slightly at the lowest and intermediate doses; the slight increases were completely prevented by the coadministration of buprenorphine. Whereas changes in blood glucose levels after glucose administration in rats under sevoflurane anesthesia were significantly greater than those in awake rats, the changes in rats under propofol anesthesia were similar to those in awake rats.

CONCLUSIONS: During surgery, hyperglycemia was observed under sevoflurane and sevoflurane/buprenorphine anesthesia, but blood glucose levels were relatively stable under propofol and propofol/buprenorphine anesthesia. Whereas sevoflurane exaggerates glucose intolerance, propofol has no significant effects on glucose tolerance. We speculate that this feature of propofol contributes, at least in part, to the stable glucose metabolism during surgery observed in this study. The results of this study confirm the marked difference in the effects of sevoflurane and propofol on glucose metabolism.

METHODS: A reversible ATP depletion (antimycin A) followed by restoration of substrate supply in LLC-PK1 cells was used as an in vitro model of renal I-R. Cell viability was assessed by dimethylthiazol-diphenyltetrazol bromide and trypan blue dye exclusion test assays. Apoptosis was evaluated by annexin V–fluorescein isothiocyanate staining by flow cytometry and immunofluorescence. Propofol treatments were initiated at various time intervals: 1 or 24 h before ischemia, only during ischemia, or only during reperfusion. To evaluate the mechanisms of propofol protection, specific K_ATP channel inhibitors or activators were used in some experiments during propofol pretreatment.

RESULTS: Propofol attenuated I-R injury on LLC-PK1 cells when present either 1 or 24 h before initiated I-R, and also during the recovery period, but not when added only during ischemia. Propofol pretreatment significantly protected LLC-PK1 from I-R-induced apoptosis. The protective effect of propofol was prevented by glibenclamide (a sarcolemmal ATP-dependent K⁺ channel blocker) and decreased by 5-hydroxidecanoic acid (a mitochondrial ATP-dependent K⁺ channel blocker), but it was not modified by diazoxide (a selective opener of ATP-sensitive K⁺ channel).

CONCLUSION: Propofol protected cells against apoptosis induced by I-R. This protection was probably due to a preconditioning effect of propofol and was, at least in part, mediated by K_ATP channels.

METHODS: Neocortical astrocytes were exposed to OGD in an anaerobic chamber. After 6 h of OGD exposure, astrocytes were subsequently subjected to 24 h of reoxygenation. Propofol was added during the OGD phase of the model. Cell morphology was assessed by light microscopy. Astrocyte viability was assessed by measuring 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide absorbency (optical density value) and the percentage of lactate dehydrogenase released by injured astrocytes. AQP4 expression was evaluated with Western blot analysis. To investigate the possible mechanism of propofol’s effects on AQP4 expression, cultured astrocytes were pretreated for 24 h with the PKC activator, 12-O-tetradecanoylphorbol 13-acetate, before the propofol treatment/OGD 6 h/reoxygenation 24 h.

RESULTS: We found by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide testing that astrocyte viability began to decrease after about 4 h of OGD exposure and decreased to 60% after 6 h of OGD. When 6 h of OGD was followed by 24 h of reoxygenation, cell viability was further decreased. AQP4 expression was attenuated after 6 h of OGD exposure but was reversed and exceeded baseline levels after 24 h of reoxygenation. Propofol dose-dependently reduced cell death assessed by lactate dehydrogenase test (P < 0.05), and 10 µM propofol significantly down-regulated AQP4 expression in astrocytes after 6 h of OGD followed by 24 h of reoxygenation (P < 0.01). Prolonged (24 h) pretreatment with the phorbol ester, 12-O-tetradecanoylphorbol 13-acetate before OGD significantly reversed the effect of propofol on AQP4 expression (P < 0.01).

CONCLUSION: Propofol, administered during OGD, provided neuroprotective effects and down-regulated AQP4 expression in the OGD/reoxygenation model of cultured rat astrocytes. Activation of the PKC pathway may block the effects of propofol.

METHODS: We anesthetized homozygous G_i2 GS/GS and wild-type (WT) mice with isoflurane and quantified time (in seconds) to loss and resumption of righting response. During recovery from isoflurane anesthesia, breathing was quantified in a plethysmography chamber for both lines of mice.

RESULTS: G_i2 GS/GS mice required significantly less time for loss of righting and significantly more time for resumption of righting than WT mice. During recovery from isoflurane anesthesia, G_i2 GS/GS mice exhibited significantly greater respiratory depression. Poincaré analyses show that GS/GS mice have diminished respiratory variability compared with WT mice.

CONCLUSION: Modulation of G_i2 signaling by RGS proteins alters loss and resumption of wakefulness and state-dependent changes in breathing.

METHODS: Rat EAAT3 was expressed in Xenopus oocytes. l-glutamate- and l-cysteine-induced membrane currents were recorded using the 2-electrode voltage clamp technique. The peak current was quantified to reflect the amount of transported substrates because transport of substrates via EAATs is electrogenic.

RESULTS: Exposure of oocytes to 5 mM tert-butyl hydroperoxide, an organic oxidant, for 10 min reduced the V_max, but did not affect the K_m, of EAAT3 for l-cysteine. The volatile anesthetics isoflurane, sevoflurane, and desflurane at concentrations from 1% to 3% attenuated the tert-butyl hydroperoxide-reduced EAAT3 activity for l-glutamate and l-cysteine.

CONCLUSIONS: Our results suggest that volatile anesthetics preserve EAAT3 function to transport l-glutamate and l-cysteine under oxidative stress, which may be a mechanism for the neuroprotective effects of volatile anesthetics.

METHODS: We randomly allocated 66 adult obese patients with a body mass index between 30 and 50 kg/m² scheduled to undergo laparoscopic bariatric surgery into 3 groups. According to the recruitment maneuver used, the zero end-expiratory pressure (ZEEP) group (n = 22) received the vital capacity maneuver (VCM) maintained for 7–8 s applied immediately after intubation plus ZEEP; the positive end-expiratory pressure (PEEP) 5 group (n = 22) received the VCM maintained for 7–8 s applied immediately after intubation plus 5 cm H₂O of PEEP; and the PEEP 10 group (n = 22) received the VCM maintained for 7–8 s applied immediately after intubation plus 10 cm H₂O of PEEP. All other variables (e.g., anesthetic and surgical techniques) were the same for all patients. Heart rate, noninvasive mean arterial blood pressure, arterial oxygen saturation, and alveolar-arterial Pao₂ gradient (A-a Pao₂) were measured intraoperatively and postoperatively in the postanesthesia care unit (PACU). Length of stay in the PACU and the use of a nonrebreathing O₂ mask (100% Fio₂) or reintubation were also recorded. A computed tomographic scan of the chest was performed preoperatively and postoperatively after discharge from the PACU to evaluate lung atelectasis.

RESULTS: Patients in the PEEP 10 group had better oxygenation both intraoperatively and postoperatively in the PACU, lower atelectasis score on chest computed tomographic scan, and less postoperative pulmonary complications than the ZEEP and PEEP 5 groups. There was no evidence of barotrauma in any patient in the 3 study groups.

CONCLUSIONS: Intraoperative alveolar recruitment with a VCM followed by PEEP 10 cm H₂O is effective at preventing lung atelectasis and is associated with better oxygenation, shorter PACU stay, and fewer pulmonary complications in the postoperative period in obese patients undergoing laparoscopic bariatric surgery.

METHODS: In this prospective observational study conducted in a biochemistry laboratory, we analyzed 179 routine blood samples from consecutive patients over a 3-mo period using two automated blood chemistry analyzers, the LX20 (Beckman) and the Modular (Roche). Measured and calculated parameters from the two analyzers were compared.

RESULTS: Although the correlation between measured values was satisfactory, there were large differences in the limits of agreement for calculated values (SID_app: 9.6 mEq/L, SID_eff: 6.4 mEq/L, and SIG: 11.7 mEq/L) and a weak correlation (SID_app: r² = 0.54 and SIG: r² = 0.12) between the analyzers.

CONCLUSIONS: The results of the Stewart-Fencl approach for interpretation of acid-base status can vary according to the analyzer used. These differences may have important clinical and research implications..

METHODS: A syringe pump infused a saline carrier solution at a low flow rate frequently used in an intensive care unit (10 mL/h) through a multiport manifold connected to the 16-gauge lumen of a standard 16-cm triple-lumen catheter. The model drug methylene blue (3 mL/h) joined the carrier flow at the first, second, or fourth stopcock of a traditional manifold or 1 of 2 positions in a microinfusion manifold, a new device designed to minimize dead volume. Effluent samples were collected every minute for quantitative spectrophotometric analysis of delivery onset and offset.

RESULTS: Onset and offset times differed significantly among individual ports of the traditional 4-stopcock manifold. There was also a significant difference between the 2 ports of the microinfusion manifold, but this was less pronounced. Both ports of the microinfusion manifold yielded delivery dynamics that were similar to the most downstream port of the 4-stopcock manifold. There was good correlation between dynamic data and dead volume for each of the manifolds.

CONCLUSIONS: Using a traditional stopcock manifold, port selection significantly affects drug delivery dynamics for continuous infusions. The findings provide quantitative support for the concept that the most critical infusion should join the system at the manifold port closest to the patient. Port selection was less important for the microinfusion manifold and dynamics were faster compared with the second and fourth ports of the stopcock manifold. The smaller dead volumes of the microinfusion manifold minimize unwanted delays in drug delivery onset and offset allowing more precise control over drug delivery by continuous infusion.

METHODS: More than 5.6 million patients in the Nationwide Inpatient Sample who underwent principal procedures of knee arthroplasty, cholecystectomy, hip/femur surgical treatment, spinal fusion, appendectomy, colorectal resection, laminectomy without fusion, coronary artery bypass grafting, and cardiac valve procedures from 1996 to 2005 were included. Rates of POVL, defined as any discharge with an International Classification of Diseases, Ninth Revision, Clinical Modification code of ischemic optic neuropathy (ION), cortical blindness (CB), or retinal vascular occlusion (RVO), were estimated. Potential risk factors were assessed by univariate and multivariable analyses.

RESULTS: Cardiac and spinal fusion surgery had the highest rates of POVL. The national estimate in cardiac surgery was 8.64/10,000 and 3.09/10,000 in spinal fusion. By contrast, POVL after appendectomy was 0.12/10,000. Those undergoing cardiac surgery, spinal fusion, and orthopedic surgery had a significantly increased risk of developing ION, RVO, or CB. Patients younger than 18 yr had the highest risk for POVL, because of higher risk for CB, whereas those older than 50 yr were at greater risk of developing ION and RVO. Other significant positive predictors for some diagnoses of POVL were male gender, Charlson comorbidity index, anemia, and blood transfusion. There was no increased risk associated with hospital surgical volume. During the 10 yr from 1996 to 2005, there was an overall decrease in POVL in the procedures we studied.

CONCLUSIONS: The results confirm the clinical suspicion that the risk of POVL is higher in cardiac and spine fusion surgery and show for the first time a higher risk of this complication in patients undergoing lower extremity joint replacement surgery. The prevalence of POVL in the eight most commonly performed surgical operations in the United States has decreased between 1996 and 2005. Increased odds of POVL with male gender and comorbidity index indicate that some risk factors for POVL may not presently be modifiable. The conclusions of this study are limited by factors affecting data accuracy, such as lack of data on the intraoperative course and inability to confirm the diagnostic coding of any of the discharges in the database.

METHODS: Twenty-four nonsedated adult volunteers underwent neck magnetic resonance imaging with and without CP. Measurements were made of the postcricoid hypopharynx, airway compression, and lateral displacement of the cricoid ring during the application of CP. The relevant anatomy was reviewed.

RESULTS: The hypopharynx, not the esophagus, is what lies behind the cricoid ring and is compressed by CP. The distal hypopharynx, the portion of the alimentary canal at the cricoid level, was fixed with respect to the cricoid ring and not mobile. With CP, the mean anterioposterior diameter of the hypopharynx was reduced by 35% and the lumen likely obliterated, and this compression was maintained even when the cricoid ring was lateral to the vertebral body.

CONCLUSIONS: The location and movement of the esophagus is irrelevant to the efficiency of the Sellick’s maneuver (CP) in regard to prevention of gastric regurgitation into the pharynx. The hypopharynx and cricoid ring move together as an anatomic unit. This relationship is essential to the efficacy and reliability of Sellick’s maneuver. The magnetic resonance images show that compression of the alimentary tract occurs with midline and lateral displacement of the cricoid cartilage relative to the underlying vertebral body.

METHODS: In this prospective, observational study, we interviewed 600 patients during the preoperative visit in a tertiary referral educational hospital in northwest Iran. The definition of substance abuse and dependence was according to DSM-IV criteria. Postoperative complications and in-hospital mortality of patients with substance (cigarette, opium, and alcohol) dependence and abuse were compared with those in control patients who did not use these substances.

RESULTS: In 600 studied patients, the prevalence of cigarette smoking was 42.1% (ex-smokers 26.0% and current smokers 16.1%), prevalence of opium use was 12.0% (opium abuse 7.0% and opium dependence 5.0%), and alcohol consumption was 8.1% (alcohol abuse 7.4% and alcohol dependence 0.7%). The prevalence of cigarette smoking was 58.9% in men and 7.6% in women (P = 0.001). Postoperative cardiac complications in current smokers (21.5%) and ex-smokers (20.5%) were not significantly different from the control group (28.2%). Also, pulmonary complications were not different in current smokers (24.7%) and ex-smokers (17.9%) from the control group (26.8%; P = 0.196). However, in men, pulmonary complications in current smokers were more prevalent than in the control group (P = 0.044). In opium and alcohol dependents and abusers, postoperative complications were not statistically different from the control group (all P values >0.05). No increase was observed regarding in-hospital mortality in patients with substance use.

CONCLUSIONS: In cardiac surgery patients in northwest Iran, the prevalence of cigarette smoking is relatively low (very low in women), as is alcohol use, compared with Western countries; however, opium use is twice as prevalent. We found higher pulmonary complication rates in men who smoked, but no increase in postoperative cardiopulmonary complications and in-hospital mortality rates in patients who abused opium and consumed alcohol.

METHODS: One hundred fifty consecutive adult morbidly obese patients (body mass index >35 kg/m²) were randomly selected to receive one of 3 VLSs: GlideScope®, Storz® V-Mac^TM, and McGrath®. Direct laryngoscopy scored the best possible view of the glottis; subsequently, the respective VLS was used, and the patient's trachea was intubated. Common preprocedural (e.g., Mallampati grade) and intraprocedural (Cormack-Lehane grade) metrics of intubation difficulty were measured, as well as the dependent variables of intubation time, number of attempts, and subjective difficulty.

RESULTS: All 3 VLSs tested offered an equal or better view of the glottis compared with traditional direct laryngoscopy. The number of attempts necessary to intubate the trachea differed significantly among VLSs (average 2.6 ± 1.0 attempts for the GlideScope, 1.4 ± 0.7 for the Storz, and 2.9 ± 0.9 for the McGrath VLS). The average intubation times were 33 ± 18 s for the GlideScope, 17 ± 9 s for the Storz, and 41 ± 25 s for the McGrath VLS.

CONCLUSIONS: In this study, the VLS with the Macintosh blade (Storz VLS) had a better overall satisfaction score, intubation time, number of intubation attempts, and necessity of extra adjuncts, compared with the 2 other tested devices.

METHODS: In 16 anesthetized pigs (31.4 ± 3.4 kg), a jugular vein, a carotid artery, the pulmonary artery (thermodilution), the portal vein, and a hepatic vein were cannulated for hemodynamic monitoring and blood sampling. Ultrasonic flowprobes were placed around the portal vein, the hepatic artery, and the superior mesenteric artery (SMA). In addition to 30 mL/kg of dextran 70 given before baseline, all animals received 10 mL · kg^–1 · h^–1 of IV fluids throughout the experiment. An endotoxin infusion (2 µg · kg^–1 · h^–1) was given for 300 min; 100 min after the start of endotoxin, the pigs were randomized to receive levosimendan (50 µg · kg^–1 · h^–1, n = 8) or placebo (n = 8). To evaluate the isolated effects of endotoxemia, all data before randomization were pooled into one group. Data were analyzed by analysis of variance and presented as mean ± sem.

RESULTS: Endotoxemia (t = 90 min, pooled data) decreased systemic vascular resistance (SVR, 2526 ± 203 to 1946 ± 122 dyn · s · cm^–5, P = 0.003) and mean arterial blood pressure (MAP, 109 ± 6 to 84 ± 3 mm Hg, P < 0.05), whereas heart rate (66 ± 4 to 98 ± 8 bpm), and mean pulmonary arterial pressure (MPAP, 20 ± 1 to 38 ± 2 mm Hg) increased (P < 0.001). Cardiac output (CO, 3.4 ± 0.2 L/min) and systemic oxygen delivery (414 ± 33 mL/min) were unchanged, but blood flows in the SMA (575 ± 34 to 392 ± 38 mL/min) and the portal vein (881 ± 62 to 568 ± 39 mL/min) decreased (P < 0.001). Although hepatic arterial blood flows increased (36 ± 8 to 219 ± 38 mL/min), gut (114 ± 11 to 84 ± 7 mL/min) and hepatic (94 ± 11 to 67 ± 8 mL/min) oxygen deliveries decreased (P < 0.05). At t = 300 min, the levosimendan group showed lower MPAP (39 ± 3 vs 49 ± 2 mm Hg, P = 0.025), lower SVR (2158 ± 186 vs 3069 ± 370 dyn · s · cm^–5, P = 0.052), and lower MAP (55 ± 9 vs 87 ± 9 mm Hg, P < 0.001) than the control group. In both groups, CO, portal vein, and hepatic arterial blood flows decreased (P < 0.001); the mean values for the levosimendan group at t = 300 min were 2.0 ± 0.4 L/min, 390 ± 83 mL/min, and 36 ± 12 mL/min, respectively. SMA blood flow decreased only in the levosimendan group (432 ± 40 to 320 ± 78 mL/min, P < 0.001), whereas gut oxygen delivery decreased in the levosimendan (85 ± 12 to 63 ± 12 mL/min, P < 0.001) and in the control (83 ± 6 to 59 ± 3 mL/min, P = 0.03) groups.

CONCLUSION: Levosimendan administered after the establishment of endotoxemic shock to pigs receiving moderate fluid resuscitation prevented further increases in MPAP and maintained a low SVR. There were, however, no improvements in CO, MAP decreased, and levosimendan neither prevented the development of circulatory shock nor improved hepatosplanchnic perfusion.

METHODS: Twenty anesthetized pigs (26.8 ± 0.5 kg) were instrumented with flow probes and catheters to monitor systemic and regional perfusion as described in our companion article in this issue of the journal. Two animals were excluded because of surgical complications. Oxygen consumption (VO₂) was measured by indirect calorimetry. Starting 1 h after instrumentation, an endotoxin infusion (Escherichia coli lipopolysaccharide, 2 µg · kg^–1 · h^–1) was administered for 300 min. Sixty minutes after the start of endotoxin, the animals were fluid resuscitated (20 mL/kg dextran 70); at 120 min, they were randomized into three groups of six animals each: levosimendan (25–50 µg · kg^–1 · h^–1), dobutamine (10–20 µg · kg^–1 · min^–1), and control. In the first two groups, norepinephrine (0.5–2 µg · kg^–1 · min^–1) was added when mean arterial blood pressure (MAP) ≤ 65 mm Hg. Crystalloids were given to maintain filling pressures ≥ baseline. The data were divided into two subsets: before (0–120 min, all animals) and after (120–300 min, three groups) randomization, and analyzed by analysis of variance. P < 0.05 was considered significant.

RESULTS: At 120 min, cardiac output was 15% higher (P < 0.001), systemic vascular resistance was 30% lower (P < 0.001), and MAP decreased 12.5% (P = 0.004); blood flow in the hepatic artery, superior mesenteric artery, and portal vein had increased by 100% (P = 0.004), 60% (P < 0.001), and 20% (P < 0.001), respectively. Between 120 and 300 min, cardiac output and systemic oxygen delivery decreased 50% in control animals (P < 0.05), remained unchanged in the levosimendan group, and increased 60% with dobutamine (P = 0.05). MAP (P = 0.043) and VO₂ (P = 0.001) decreased 20% in the control group. Portal vein flow decreased in the control (50%) and levosimendan (30%) groups (P < 0.001) and was therefore higher in the dobutamine group (P = 0.003) at 300 min. Hepatic and gut oxygen deliveries decreased in the levosimendan (50%, and 30%, respectively, P < 0.001) and control groups (70% and 45%, respectively, P < 0.05); thus, regional oxygen deliveries were greater in the dobutamine group (P < 0.05). In this group, mixed venous and hepatic vein oxygen saturation were maintained; the latter variable was higher than in the other groups (P < 0.05). Although unchanged with dobutamine, arterial (P = 0.020), portal (P = 0.020), and hepatic vein (P = 0.034) lactate concentrations increased twofold with levosimendan.

CONCLUSION: In volume-resuscitated endotoxemic pigs, the association of either levosimendan or dobutamine with norepinephrine preserved systemic blood flow, oxygen delivery, and VO₂. However, only dobutamine-norepinephrine maintained portal blood flow, which was associated with preservation of splanchnic and hepatic oxygen homeostasis and stable lactate concentrations.

METHODS: We performed a prospective observational cohort study in a 21-bed polyvalent intensive care unit in a university hospital.

RESULTS: Three hundred sixty-one intubated adult patients with a duration of mechanical ventilation (MV) of 6 days or more were admitted over a 28-mo period. Late-onset VAP was confirmed in 76 patients (21%) by the presence of at least one microorganism at a concentration ≥10⁴ colony-forming units/mL on the bronchoalveolar lavage. Gram-negative bacilli represented 75% and Staphylococcus aureus 21% of recovered organisms. Factors independently associated with late-onset VAP by multivariate analysis included a high simplified acute physiology score II score (odds ratio: 1.021; 95% confidence interval [CI]: 1.005–1.038; P = 0.01), development of acute respiratory distress syndrome during the first 5 days of MV (odds ratio: 1.98; 95% CI: 1.05–3.67; P = 0.04), and size of the endotracheal tube ≥7.5 (odds ratio: 2.06; 95% CI: 1.88–3.90; P = 0.03). EN started within 48 h of MV onset was not associated with a higher risk for late-onset VAP.

CONCLUSION: In our nontrauma patient population, early EN was not associated with development of late-onset VAP. In this population, severity of the disease during the first 5 days of MV seemed to be associated with late-onset VAP. In addition, our results suggest that the risk of late-onset VAP is higher in patients with a tube size ≥7.5 than in patients with a tube size <7.5.

METHODS: Male Sprague-Dawley rats weighing 250-300 g were randomly assigned to 1 of 4 groups: sham rats (injected intraperitoneally [IP] with saline) pretreated with vehicle (100% O₂) (sham-vehicle); sham rats pretreated with isoflurane (sham-ISO); LPS rats (injected IP with LPS) pretreated with vehicle (vehicle-LPS); and LPS rats pretreated with isoflurane (ISO-LPS). Endotoxemia was induced by IP injection of LPS. Isoflurane 1.4% was administered 30 min before LPS injection. The animals were then observed for 6 h. We monitored arterial blood pressure, heart rate, and blood gas. The extent of ALI was evaluated by lung wet/dry ratio, Evans blue dye extravasation, and histologic examination. We also measured pulmonary nitric oxide (NO), tumor necrosis factor (TNF)-, interleukin (IL)-1β, and IL-6 levels. In addition, survival statistics and pulmonary inducible NO synthase (iNOS) gene expression were also determined.

RESULTS: LPS caused systemic hypotension and severe ALI, as evidenced by the increases in the extent of ALI, impairment of pulmonary functions, and increases in pulmonary NO, TNF-, IL-1β, and IL-6. Isoflurane preconditioning mitigated systemic hypotension and the development of ALI. Isoflurane preconditioning also attenuated the LPS-induced increases in pulmonary nitrate/nitrite and proinflammatory cytokine release and improved survival of rats with severe sepsis. The expression of iNOS was upregulated by LPS and reduced by isoflurane pretreatment.

CONCLUSIONS: Isoflurane preconditioning can attenuate pulmonary proinflammatory cytokine release and decrease the mortality induced by severe sepsis. Early protection seems to be mediated partly through inhibition of iNOS-NO pathway activation.

METHODS: Sixty women presenting for elective cesarean delivery were randomly assigned to one of the 3 groups. Group 7 received intrathecal hyperbaric bupivacaine 7 mg, Group 8 received 8 mg, and Group 9 received 9 mg. Women in all 3 groups received intrathecal morphine 100 µg and IV hydroxyethyl starch 15 mL/kg at the time of initiation of combined spinal-epidural anesthesia. Surgery began when a sensory level of T4 was achieved. Patients were monitored for block characteristics and side effects by a blinded observer. Our primary outcome was the maximum cephalad sensory block height.

RESULTS: There was a difference in the maximum extent of cephalad sensory block among groups (Group 7: median T2 [interquartile range T2–T3]; Group 8: median T2 [T1–T2]; Group 9: median T1 [C8–T2]; P = 0.02). However, the time taken to reach T4 was similar in all 3 groups. The incidence of hypotension requiring vasopressors was different among groups (30% in Group 7, 55% in Group 8, and 70% in Group 9; P = 0.04). No patient had inadequate anesthesia. Neonatal outcomes were similar in all 3 groups.

CONCLUSION: The lowest dose of hyperbaric bupivacaine (7 mg) provided equally rapid onset and effective anesthesia for cesarean delivery while reducing the incidence of hypotension compared with 8 and 9 mg. However, because of its shorter duration of anesthesia, it may be feasible only when the block can be reinforced using a functional epidural catheter.

METHODS: Two hundred eight parturients who developed moderate to severe pruritus after the administration of intrathecal morphine were randomly allocated to 2 groups: IV pentazocine 15 mg (n = 104) and IV ondansetron 4 mg (n = 104). The successful treatment of pruritus (no or mild pruritus) and other adverse effects were determined 15 min after study drug administration, and patients were observed for recurrence of pruritus for 4 h.

RESULTS: The treatment success rate at 15 min was higher in the pentazocine group (96.1%) than in the ondansetron group (80.8%) (95% confidence interval of difference: 7.0%, 23.8%; P = 0.001). The recurrence rate of moderate to severe pruritus within 4 h after treatment in the pentazocine group (12.0%) was lower than in the ondansetron group (32.1%) (P = 0.001). There were no significant differences between groups in nausea/vomiting, sedation, shivering, pain scores, and pain at injection site. No respiratory depression was observed.

CONCLUSIONS: Pentazocine 15 mg is superior to ondansetron 4 mg for the treatment of intrathecal morphine-induced pruritus and has a lower recurrence rate. The side effects after treatment are mild.

METHODS: The setting is the preanesthesia evaluation clinic (PAC) of a university hospital, where patients consult several medical professionals, either by walk-in or appointment. Queuing theory was used to model the initial set-up of the clinic, and later to model possible alternative designs. With the queuing model, possible improvements in efficiency could be investigated. Inputs to the model were patient arrival rates and expected service times with clinic employees, collected from the clinic's logging system and by observation. The performance measures calculated with the model were patient length of stay and employee utilization rate. Supported by the model outcomes, a working group consisting of representatives of all clinic employees decided whether the initial design should be maintained or an intervention was needed.

RESULTS: The queuing model predicted that 3 of the proposed alternatives would result in better performance. Key points in the intervention were the rescheduling of appointments and the reallocation of tasks. The intervention resulted in a shortening of the time the anesthesiologist needed to decide upon approving the patient for surgery. Patient arrivals increased sharply over 1 yr by more than 16%; however, patient length of stay at the clinic remained essentially unchanged. If the initial set-up of the clinic would have been maintained, the patient length of stay would have increased dramatically.

CONCLUSIONS: Queuing theory provides robust methods to evaluate alternative designs for the organization of PACs. In this article, we show that queuing modeling is an adequate approach for redesigning processes in PACs.

METHODS: Three hundred forty-seven fasting patients had a preoperative glucose measurement determined from blood residue left on the IV needle, measured with an Accu-Chek glucometer (Roche Diagnostics, Indianapolis, IN).

RESULTS: After excluding patients with a diabetes history, 4.0% had a glucose measurement between 100 and 125 mg/dL, at a cost of $14.22 per identification, and 1.2% had a glucose measurement more than 125 mg/dL, at a cost of $32.00 per identification.

CONCLUSIONS: This preoperative blood glucose screening test was implemented at a cost of approximately one-tenth of current methods.

METHODS: Eighty patients undergoing craniotomy for supratentorial tumor resection were randomly assigned into two groups. Patients in Group G (n = 40) received oral gabapentin (3 x 400 mg), and patients in Group P (n = 40) received oral phenytoin (3 x 100 mg) for 7 days before the operation and postoperatively. An identical anesthesia protocol was performed for both the groups. Anesthesia was maintained with propofol and remifentanil infusion. Patient-controlled analgesia with morphine was used, and pain levels were measured. The antiepileptic-related side effects, anesthetic consumption, duration of anesthesia and surgery, tracheal extubation time, postoperative pain scores, morphine consumption, and sedation scores were recorded.

RESULTS: Thirty-seven patients in Group G and 38 patients in Group P completed the study. During the preoperative period in Group G, one patient had severe fatigue, one had severe dizziness, and one patient’s surgical procedure was changed. The median plasma levels of gabapentin were 34 µmol/mL (range, 23-51 µmol/mL) in 34 patients. In Group P, one patient withdrew from the study preoperatively and one developed transient neurological symptoms postoperatively.

The demographic data and mean duration of anesthesia and surgery were similar in both the groups. The total propofol and remifentanil consumption in Group G (1847 ± 548 mg/3034 ± 1334 µg) was significantly less than that of Group P (2293 ± 580 mg/4287 ± 1282 µg) (P = 0.01). However, tracheal extubation could be done earlier in Group P (4.5 ± 2 min) than in Group G (16.6 ± 22 min) (P < 0.001). Pain scores were significantly higher in Group P at 15 min, 30 min, and 1 h (P < 0.001). The total morphine consumption was also significantly higher in Group P (33 ± 17 mg vs 24 ± 19 mg) (P = 0.01). The postoperative sedation scores were significantly higher in Group G at 15 min, 30 min, 1 h, and 2 h (P < 0.001).

CONCLUSIONS: The administration of gabapentin to patients undergoing craniotomy for supratentorial tumor resection was effective for acute postoperative pain. It also decreased analgesic consumption after surgery. However, it may lead to side effects such as delayed tracheal extubation and increased sedation postoperatively.

METHODS: Seventy male sevoflurane-anesthetized Sprague Dawley rats were randomly assigned to the following treatment groups: normothermic ischemia, intraischemic hypothermia, and postischemic hypothermia with corresponding sham-operated controls. Fifteen naïve rats were investigated as reference for natural neurogenesis. Forebrain ischemia was induced by bilateral common carotid artery occlusion and hemorrhagic hypotension. In normothermic groups, the pericranial temperature was maintained at 37.5°C. Animals in the hypothermic groups were cooled to a pericranial temperature of 33°C for 45 min. All animals received 5-bromo-2-deoxyuridine for 7 days. Histopathological damage and 5-bromo-2-deoxyuridine-positive neurons of the hippocampus were analyzed after 28 days.

RESULTS: Hypothermia had no impact on natural neurogenesis. Cerebral ischemia increased the number of new neurons regardless of pericranial temperature. Forty-five minutes of hypothermia beginning before ischemia diminished hippocampal injury to <10% in the CA1 and CA3 regions, whereas 45 min of postischemic hypothermia beginning after reperfusion did not reduce neuronal injury compared with normothermia.

CONCLUSIONS: Neither intraischemic nor postischemic hypothermia affected the ischemia-induced increase in endogenous neurogenesis. Intraischemic hypothermia reduced hippocampal damage, whereas postischemic hypothermia as applied here did not prevent formation of histopathological injury. This indicates that, 28 days after cerebral ischemia, postischemic neurogenesis is not significantly increased by mild peri-ischemic hypothermia and not affected by the severity of histopathological damage.

METHODS: Sixty patients undergoing abdominal hysterectomy were randomly assigned to 1 of the following 3 groups: control group received oral placebo capsules and bolus plus infusion of saline; ketamine group received oral placebo capsules and, before incision, 0.3 mg/kg IV bolus and 0.05 mg·kg^–1·h^–1 infusion of ketamine until the end of surgery; and gabapentin group received oral gabapentin 1.2 g and bolus plus infusion of saline. The anesthetic technique was standardized, and the postoperative assessments included verbal rating scales for pain and sedation, IV morphine usage, quality of recovery assessment, recovery of bowel function, resumption of normal activities, and patient satisfaction with their pain management. Patients were questioned at 1, 3, and 6 mo after surgery for chronic postoperative pain.

RESULTS: Postoperative pain scores were significantly lower in the gabapentin group compared with the ketamine and control groups, and patient-controlled analgesia morphine use was significantly reduced in both treatment groups (versus control group) (P < 0.001). Total patient-controlled analgesia morphine use was decreased by 35% and 42% in the ketamine and gabapentin groups, respectively, compared with the control group (P < 0.001). Patient satisfaction with pain treatment was significantly improved in the ketamine and gabapentin groups compared with the control group (P < 0.001).

The incidence of incisional pain and related pain scores at the 1-, 3-, and 6-mo follow-up were significantly lower in the gabapentin group compared with the ketamine and control groups (P < 0.001).

CONCLUSION: Gabapentin and ketamine are similar in improving early pain control and in decreasing opioid consumption; however, gabapentin also prevented chronic pain in the first 6 postoperative months.

METHODS: One hundred thirty-two patients with acute herpes zoster diagnosed 1–7 days after the onset of the rash were randomly assigned to receive either standard therapy (oral antivirals and analgesics) or standard therapy with additional repetitive paravertebral injections of a mixture of 10 mL 0.25% bupivacaine and 40 mg methylprednisolone acetate every 48 h for a week. Efficacy was evaluated at 1, 3, 6, and 12 mo after the end of the treatments. The primary end point was the proportion of patients with zoster-associated pain and/or allodynia 1 mo after inclusion. Statistical analysis was performed based on the intent-to-treat population.

RESULTS: One hundred thirteen patients completed the 1-yr follow-up. At 1 mo posttherapy, 13% of patients in the paravertebral group reported zoster-related pain, compared with 45% in the standard group (P < 0.001). At 3, 6, and 12 mo posttherapy, the incidence of PHN was still significantly lower in the paravertebral group than in the standard group. The quality of life improved in both groups at each follow-up time point with no significant difference between groups.

CONCLUSION: Repetitive paravertebral anesthetic block in combination with steroids plus standard treatment with acyclovir and analgesics significantly reduced the incidence of PHN than the standard treatment alone.

METHODS: Therefore, a spinal block was administered in male Wistar rats by administering a local anesthetic (bupivacaine) through an intrathecal catheter at the mid-thoracic level. This thoracic spinal block completely suppressed the noxious stimulation-induced withdrawal reflex that is normally elicited by electrical stimulus. Fos immunoreactivity (Fos-IR) was quantified in all laminae of the L4 segment of the spinal cord.

RESULTS: Noxious stimulation resulted in a general and strong increase in Fos-IR in the ipsilateral dorsal horn, mainly in Laminae I, II, and V. Thoracic spinal block caused a remarkable increase in the amount of Fos-IR in Lamina V, but had no significant effect on the Fos-IR in Laminae I and II.

CONCLUSIONS: The increase in Fos-IR in Lamina V may have resulted from the interruption of a pain-modulating descending mechanism from the brain. A known modulating descending mechanism is the serotonergic system, controlled by the periaqueductal gray. This system inhibits the neurons in the superficial laminae. Another nonserotonergic system originates in the anterior pretectal nucleus. The latter facilitates neurons in the superficial laminae, while neurons in Lamina V are inhibited. We conclude that both systems are probably involved in the observed effects of the peripheral noxious stimulation given in the present model.

METHODS: Rats were divided into four groups (n = 24 each): control, trauma, trauma (T) + sham EA, and T + EA. EA was applied to Zusanli (ST36) and Lanwei (Extra37) acupoints at 20 min after surgery for 30 min, and then performed once a day on postoperative days 1–5. Splenic T cells were isolated and the production and mRNA expression of interleukin (IL)-2, interferon-, IL-4, and IL-10 were assayed. The activation of mitogen-activated protein kinase and the DNA binding activity of nuclear factor (NF)-B and activator protein (AP)-1 were examined.

RESULTS: Paw withdrawal threshold and paw withdrawal latency were significantly increased in the T + EA group compared with the trauma group from postoperative day 1 (paw withdrawal threshold: 5.8 ± 0.7 vs 3.0 ± 0.7 g; paw withdrawal latency: 7.0 ± 0.8 vs 4.5 ± 0.5 s; P < 0.001) to day 5 (9.0 ± 0.6 vs 5.5 ± 0.6 g; 12.0 ± 1.3 vs 7.0 ± 0.8 s; P < 0.001). Th1 cytokine (IL-2 and interferon-) production and mRNA expression in splenic T cells of traumatized rats were significantly decreased on postoperative day 3 (P < 0.001, trauma group versus control group), whereas Th2 cytokine (IL-4 and IL-10) production and mRNA expression were increased (P < 0.001). This was accompanied with a significant depression in the activity of extracellular-regulated protein kinase (ERK)1/2, p38, NF-B, and AP-1 (P < 0.001, trauma group versus control group). EA administration increased Th1 cytokine protein and mRNA expression, suppressed Th2 cytokine protein and mRNA expression (P < 0.05, T + EA group versus trauma group), and increased the activity of ERK1/2, p38, NF-B, and AP-1 (P < 0.001, T + EA group versus trauma group).

CONCLUSIONS: EA regulates a balance between Th1 and Th2 cytokines at protein and mRNA levels in splenic T cells, and, at least in part, involves the signaling pathways of ERK1/2, p38, NF-B, and AP-1. The findings suggest that EA may improve immune suppression after surgical trauma.

METHODS: After premedication and single-injection femoral nerve block, 60 patients undergoing knee arthroscopy were randomly allocated to receive a sciatic nerve block with either NS (n = 30) or US (n = 30). In the US group, the sciatic nerve was localized between the ischial tuberosity and the greater trochanter. In the NS group, the appropriate muscular response (foot plantar flexion or inversion) was elicited (1.5 mA, 2 Hz, 0.1 ms) and maintained to ≤0.5 mA. The volume of the injected local anesthetic was varied for consecutive patients based on an up-and-down method, according to the response of the previous patient. The initial volume was 12 mL. An independent observer evaluated the occurrence of complete loss of pinprick sensation and motor block: positive or negative responses within 20 min after the injection determined a 2-mL decrease or increase for the next patient, respectively.

RESULTS: The mean MEAV₅₀ for sciatic nerve block was 12 mL (95% confidence interval [CI], 10–23 mL) in Group US and 19 mL (95% CI, 15–23 mL) in Group NS (P < 0.001). The effective dose in 95% of cases was 14 mL (95% CI, 12–17 mL) in Group US and 29 mL (95% CI, 25–40 mL) in Group NS (P = 0.008).

CONCLUSIONS: US provided a 37% reduction in the MEAV₅₀ of 1.5% mepivacaine required to block the sciatic nerve compared with NS.

METHODS: One hundred twelve patients scheduled for elective forearm surgery under axillary brachial plexus block were randomly allocated to receive 34 mL lidocaine 1.5% with 3 mL of isotonic saline chloride (control group, n = 28), 34 mL lidocaine 1.5% with 2 mL (100 µg) of fentanyl and 1 mL of isotonic saline chloride (fentanyl group, n = 28), 34 mL lidocaine 1.5% with 2 mL saline chloride and 100 ng (1 mL) naloxone (naloxone group, n = 28), or 34 mL lidocaine 1.5% with 2 mL (100 µg) of fentanyl and 100 ng (1 mL) naloxone (naloxone + fentanyl group, n = 28). A multiple stimulation technique was used in all patients. After performing the block, sensory and motor blockades of radial, median, musculocutaneous, and ulnar nerves were recorded at 5, 15, and 30 min. The onset time of the sensory and motor blockades was defined as the time between the last injection and the total abolition of the pinprick response and complete paralysis, respectively. The duration of sensory and motor blocks was considered as the time interval between the complete block and the first postoperative pain and complete recovery of motor functions.

RESULTS: Sensory and motor onset times were longer in the naloxone (sensory onset time: 15 ± 3, and motor onset time: 21 ± 4) and naloxone + fentanyl group than control or fentanyl groups (sensory onset time: 10 ± 3 min in control group, 10 ± 4 min in fentanyl group, and 17 ± 3 min in naloxone + fentanyl group, motor onset time: 15 ± 5 min in control group, 14 ± 7 min in fentanyl group, and 17.3 ± 3.4 min in naloxone + fentanyl group) (P < 0.001). The duration of time to first postoperative pain and motor blockade was significantly longer in the naloxone (92 ± 10 and 115 ± 10 min) and naloxone + fentanyl groups (98 ± 12 and 122 ± 16 min) than control (68 ± 7 and 89 ± 11 min) and fentanyl groups (68 ± 11 and 90 ± 12 min) (P < 0.001). The time to first postoperative pain was significantly longer in the naloxone and naloxone + fentanyl groups than in the control or fentanyl groups (P < 0.001).

CONCLUSIONS: The addition of an ultra-low dose of naloxone to lidocaine 1.5% solution with or without fentanyl solution in axillary brachial plexus block prolongs the time to first postoperative pain and motor blockade but also lengthens the onset time.

METHODS: Fifty male patients undergoing transurethral surgery received either 8 mg oral ondansetron the evening before surgery plus IV 8 mg ondansetron 15 min before subarachnoid anesthesia or placebo. All patients received 2.2 mL of 0.75% plain ropivacaine intrathecally. Sensory and motor block were assessed 30 min after the intrathecal injection and every 30 min thereafter until recovery from the motor block.

RESULTS: Thirty minutes after spinal injection of ropivacaine, we first measured, in both groups, the time to maximum block for both sensory and motor modalities. The maximum level of the sensory block, defined as decreased sensation, was T8 in the control and T6 in the ondansetron group, and absence of sensation was defined as T11 and T9 for the control and the ondansetron groups, respectively. Regarding block duration, 180 min after spinal injection, sensory block was detected in 11 of 22 and 16 of 24 patients and motor block in 1 of 22 and 0 of 24 in the control and ondansetron groups, respectively. Sensory and motor block did not differ between groups at any measured time point.

CONCLUSIONS: Ondansetron had no effect on the subarachnoid sensory or motor block produced by ropivacaine.

METHODS: Two hundred twenty-seven patients were enrolled in this prospective cohort study. Fifty-nine patients underwent CABG surgery with CPB and 168 underwent off-pump surgery. Cerebral microemboli were measured continuously with bilateral transcranial Doppler ultrasonography of the middle cerebral arteries. A neuropsychological test battery that included seven tests with nine subscales was administered at baseline, as well as at 1 wk and 3 mo after surgery. POCD was defined using the international study of POCD1 definition.

RESULTS: The median total number of cerebral microemboli for the case was 430 (range: 155–2088) in patients undergoing surgery with CPB and 2 (0–66) in the off-pump patients (P < 0.001). There were no differences in the incidence of POCD between the patients having surgery with or without CPB either at 1 wk (55.2% or 32 of 58 patients [95% confidence interval: 41.5%–68.3%] vs 47.0% or 78 of 166 patients [39.2%–54.9%], P = 0.283) or 3 mo (6.4% or 3 of 47 patients [1.3%–17.5%] vs 13.1% or 16 of 122 of patients [7.7%–20.4%], P = 0.214) after surgery. Increasing age and shorter duration of postoperative hospital stay were independently associated with cognitive dysfunction at 1 wk after surgery. Increasing age and a history of diabetes mellitus were independently associated with cognitive dysfunction 3 mo after surgery. CPB or cerebral microemboli were not significantly related to the occurrence of POCD.

CONCLUSIONS: In Chinese population, avoidance of CPB during CABG surgery significantly decreased the number of cerebral microemboli, but it did not decrease the incidence of POCD at either 1 wk or 3 mo after CABG. Neither CPB nor cerebral microemboli was independently associated with the risk of POCD.

METHODS: Normal whole blood was incubated with increasing amounts of a nonspecific antibody, an anti-GPIIb/IIIa antibody, or a neutralizing anti-factor XIII antibody; samples were analyzed with a tissue factor-activated and platelet-inhibited whole blood thrombelastographic assay. Clotting time, clot formation time, maximum clot firmness, and clot lysis at 60 min were evaluated in triplicate. Also, 25 whole blood routine samples were evaluated for factor XIII deficiency using a new thrombelastographic assay incorporating a factor XIII antibody and using a standard factor XIII assay for comparison.

RESULTS: Although GPIIb/IIIa inhibition did not alter the results of the platelet-inhibited whole blood thrombelastography, factor XIII inhibition significantly reduced maximum clot firmness (P = 0.020) and increased clot formation time (P = 0.025) and clot lysis (P = 0.007), leaving clotting time unchanged; a ceiling effect seemed to be present with increasing antibody concentrations in whole blood (but not plasma). The thrombelastographic assay for factor XIII deficiency (<70% activity) had a 90% sensitivity and negative predictive value (area under receiver operating characteristic curve 0.803, P = 0.0015); for a deficiency <60%, sensitivity and negative predictive value were 100% (area under receiver operating characteristic curve 0.84, P = 0.0037).

CONCLUSION: Factor XIII has significant impact on platelet-inhibited activated whole blood thrombelastography. This phenomenon should be considered when interpreting thrombelastographic results in the bleeding patient, especially when the results trigger procoagulant therapy. Antibody-mediated factor XIII inhibition can be used to establish thrombelastography-based assays to detect factor XIII deficiency.

METHODS: A literature search was undertaken using multiple search engines and the appropriate articles were reviewed by the authors to determine anesthetic-associated complications in patients with muscular dystrophy. Of all the types of muscular dystrophy, Duchenne muscular dystrophy (DMD) and Becker dystrophy (BD) represent nearly all the anesthesia-related reports.

RESULTS: Anesthetic complications in patients with DMD and BD include intraoperative heart failure, inhaled anesthetic-related rhabdomyolysis (absence of succinylcholine), and succinylcholine-induced rhabdomyolysis and hyperkalemia.

CONCLUSION: We did not find an increased risk of malignant hyperthermia susceptibility in patients with DMD or BD compared with the general population. However, dystrophic patients who are exposed to inhaled anesthetics may develop disease-related cardiac complications, or rarely, a malignant hyperthermia-like syndrome characterized by rhabdomyolysis. This latter complication may also occur postoperatively. Succinylcholine administration is associated with life-threatening hyperkalemia and should be avoided in patients with DMD and BD.

METHODS: We performed this study in a prospective, randomized, observer-blind manner. Children aged 1–5 yr received a constant dose of 2.25 mg/kg of ropivacaine prepared as either 1.0 mL/kg of 0.225% (low volume/high concentration [LVHC], n = 37) or 1.5 mL/kg of 0.15% solution (high volume/low concentration [HVLC], n = 36). Both solutions contained radiopaque dye.

RESULTS: The median spread levels with ranges in the HVLC group (confirmed by fluoroscopic examination) were significantly higher (T6, T3-11) than in the LVHC group (T11, T8-L2). There were no significant differences in recovery times, postoperative pain scores, or side effects between the two groups. After discharge, fewer children in the HVLC group required rescue oral acetaminophen compared with the LVHC group (50.0% vs 75.7%). First oral acetaminophen time was found to be significantly longer with HVLC patients than LVHC patients (363.0 min vs 554.5 min).

CONCLUSIONS: We confirmed (with fluoroscopy) that a caudal block with 1 mL/kg ropivacaine spreads to T11 and to T6 with 1.5 mL/kg. If the total dose is fixed, caudal analgesia with a larger volume of diluted ropivacaine (0.15%) provides better quality and longer duration after discharge than a smaller volume of more concentrated ropivacaine (0.225%) in children undergoing day-case orchiopexy. The spread level of ropivacaine correlated significantly with the first oral acetaminophen time after discharge.

METHODS: From January 2007 to December 2008, 384 children younger than 5-yr-of-age subjected to rigid bronchoscopy for FB removal were included in the study. The detailed clinical information and perioperative adverse events were recorded. Surgical outcomes and incidence of perioperative adverse events were compared among different ventilation modes (spontaneous ventilation, manual intermittent positive pressure ventilation, and manual jet ventilation) and different anesthetic techniques (total IV anesthesia and inhaled anesthesia). An amalgamated dataset was used for the analysis of factors that correlated with perioperative hypoxemia.

RESULTS: In children who received total IV anesthesia with spontaneous ventilation during rigid bronchoscopy, we observed more intraoperative body movement and breath holding, significantly longer duration of emergence from anesthesia, lower percentage of successful FB removal, and more postoperative laryngospasm. Children in the manual jet ventilation group had the least occurrence of intraoperative hypoxemia. Five factors strongly correlated with intraoperative hypoxemia. Younger age, plant seed as the type of FB, longer surgical duration, pneumonia before the procedure, and spontaneous ventilation mode significantly increased the risk of intraoperative hypoxemia, whereas manual jet ventilation mode decreased it. Two factors were associated with postoperative hypoxemia: plant seed as a FB and prolonged duration of emergence from anesthesia.

CONCLUSION: We identified risk factors associated with intraoperative or with postoperative hypoxemia in rigid bronchoscopy which included patient age, type of FB, duration of surgical procedure, pneumonia before the procedure, ventilation mode, and duration of emergence from anesthesia. These results provide evidence that will help clinicians to reduce the incidence of hypoxemia in high-risk children.

METHODS: As a first step, we developed an instrument based on a qualitative study conducted with children in Great Britain, input from a focus group, and input from school children. On the day of surgery, 143 children aged 7–17 yr completed a 40-item assessment of desired surgical information and a measure of anxiety (State-Trait Anxiety Inventory for Children). Parents completed a measure assessing their child’s temperament (Emotionality, Activity, Sociability, and Impulsivity Survey) and a measure of their own anxiety (State-Trait Anxiety Inventory).

RESULTS: Results indicated that the vast majority of children had a desire for comprehensive information about their surgery, including information about pain and anesthesia, and procedural information and information about potential complications. The most highly endorsed items by children involved information about pain. Children who were more anxious endorsed a stronger desire for pain information and lesser tendency to avoid information. Younger children wanted to know what the perioperative environment would look like more than adolescent children.

CONCLUSIONS: We conclude that the majority of children aged 7–17 yr who undergo surgery want to be given comprehensive perioperative information and health care providers should ensure adequate information regarding postoperative pain is provided.

METHODS: Two hundred eighteen patients were randomized to have either an i-gel or La Premiere® LM airway placed for airway management. Patients were interviewed postoperatively for throat and neck complaints at 1, 24, and 48 h. Interviewers and patients were blinded to the device used.

RESULTS: One hundred nine patients had an i-gel and 103 had a La Premiere supraglottic device inserted. The incidence of sore throat was significantly lower with the i-gel than with LM at 1 (6 vs 32), 24 (7 vs 48), and 48 h (5 vs 25). Similar results were seen for dysphagia. The incidence of neck pain was also lower for the i-gel at 24 (1 vs 7) and 48 h (1 vs 7).

CONCLUSION: In this randomized study, the i-gel supraglottic device resulted in a lower incidence of throat and neck complaints than the La Premiere LM airway.

METHODS: The effect of NMB on the median effective end-tidal concentration of desflurane (EtDes₅₀, or MAC_tetanus) for immobility was estimated using the up-and-down method and isolated forearm technique in 24 healthy volunteers. Each volunteer sequentially received saline, mivacurium, and succinylcholine in a randomized order, while EtDes concentration during each of the treatments was determined based on the movement response of the previous volunteer on the same treatment. Nonlinear mixed-effects modeling was used to evaluate the effect of NMB on BIS versus EtDes concentration relationship at baseline and after noxious stimulation, while the frontal electromyogram (EMG_BIS) effect on BIS was also modeled as a covariate. Cardiovascular responses to noxious stimulation were compared across treatments.

RESULTS: Succinylcholine and mivacurium significantly reduced MAC_tetanus (95% confidence interval) from 5.00% (4.85%–5.13%), during saline, to 4.05% (3.81%–4.29%) and 3.84% (3.60%–4.08%), respectively. Noxious stimulation significantly, although minimally, increased BIS response during all treatments. Succinylcholine increased BIS independently of an effect on EMG_BIS. Succinylcholine administration increased cardiovascular activity. Interestingly, although cardiovascular reaction to the noxious event was ablated by mivacurium, cortical response, as determined by BIS, was retained.

CONCLUSIONS: Both succinylcholine and mivacurium enhanced immobility during near-MAC anesthesia. All treatments were associated with a small, although significant, BIS increase in response to noxious stimulation, whereas succinylcholine increased BIS independently of noxious stimulation or EMG_BIS. Mivacurium suppressed autonomic response to a noxious event.

METHODS: Demographic and intraoperative data were recorded retrospectively from the anesthesia records of patients who underwent elective spine surgery longer than 8 h. Propofol patients were matched 1:2 to VA patients, based on anesthesia time (AT) (±30 min) and blood loss (BL) (±500 mL).

RESULTS: Of 246 patients identified, 50 received propofol (AT = 10 ± 2 h, BL = 1955 ± 1409 mL) and were matched to 100 VA cases (AT = 10 ± 1 h, BL = 1801 ± 1543 mL), and of those, 40 and 72 patients, respectively, had complete lactate data at baseline and at 8 h after anesthesia and were included in the main analysis. The propofol group received 8.8 ± 2 mg · kg^–1 · h^–1 of propofol. The VA group age was older than the propofol group (58 ± 12 vs 51 ± 15 yr, respectively, P = 0.002), but there was no difference between the groups in gender, ASA grade, intraoperative hemodynamic variables, and use of vasopressors. After 8 h, the VA group had a larger increase in arterial lactate from baseline compared with the propofol group (change from baseline: propofol, 0.48 ± 0.72 mmol/L; VA, 1.2 ± 1.2 mmol/L, P = 0.001).

CONCLUSIONS: During prolonged spine surgery >8 h, VA was associated with higher serum lactate, when compared with propofol infusion. Prospective studies are needed to elucidate the exact mechanisms and clinical implications of this finding.

METHODS: We determined tailflick latency (TFL) and hindpaw withdrawal latency (HPL) under 70% N₂O, N₂O MAC, and isoflurane MAC before and after intracerebroventricular injections of anti-dopamine-β hydroxylase conjugated to saporin (SAP-DBH; n = 7), or a control antibody conjugated to saporin (n = 5). In a separate group of naive rats (n = 8), N₂O MAC was determined at 25–45 min after initiation of N₂O exposure (during peak analgesia) and again at 120–140 min (after TFL and HPL returned to baseline).

RESULTS: After 30 min of N₂O exposure, TFL and HPL increased significantly but declined back to baseline within 120 min. N₂O did not produce analgesia in rats that received SAP-DBH. However, N₂O and isoflurane MAC were not significantly different between SAP-DBH and control-injected animals (Mean ± sd for N₂O: 1.7 ± 0.1 atm vs 1.7 ± 0.2 atm; isofurane: 1.6 ± 0.2% vs 1.7 ± 0.2%). In naïve animals, N₂O MAC was not different at the 30 min period compared with the 120 min period (1.8 ± 0.1 atm vs 1.8 ± 0.2 atm).

CONCLUSIONS: Destroying brainstem noradrenergic neurons or prolonged exposure to N₂O removes its analgesic effects, but does not change MAC. The immobilizing mechanism of N₂O is independent from its analgesic effects.

METHODS: In an in vitro model, mononuclear cells isolated from peripheral blood of healthy donors were preconditioned with sevoflurane (3 times 30 min at 2 vol% interspersed by 30 min of air). Colony-forming units were determined after 9 days in culture and compared with time-matched untreated control. Using magnetic cell sorting, CD133+/CD34+ endothelial progenitors were enriched from human umbilical cord blood, and vascular endothelial growth factor (VEGF), VEGFR2 (KDR), granulocyte colony-stimulating factor (G-CSF), STAT3, c-kit, and CXCR4 expressions were determined in sevoflurane-treated and untreated cells by real-time reverse transcriptase polymerase chain reaction. In a volunteer study with crossover design, we tested whether sevoflurane inhalation (<1 vol% end-tidal concentration) would mobilize endothelial progenitor cells from the bone marrow niche into the circulation using flow cytometry of peripheral blood samples. VEGF and G-CSF plasma levels were also measured.

RESULTS: In vitro sevoflurane exposure of mononuclear cells enhanced colony-forming capacity and increased VEGF mRNA levels in CD133+/CD34+ cord blood cells (P = 0.017). Sevoflurane inhalation in healthy volunteers did not alter the number of CD133+/CD34+ or KDR+/CD34+ endothelial progenitors in the circulation, but increased the number of colony-forming units (P = 0.034), whereas VEGF and G-CSF plasma levels remained unchanged.

CONCLUSIONS: Sevoflurane preconditioning promotes growth and proliferation of stem cell-like human endothelial progenitors. Hence, it may be used to promote perioperative vascular healing and to support cell replacement therapies.

METHODS: SH-SY5Y cells, a human neuroblastoma cell line, were cultured. Cells were depolarized with KCl and the phosphorylation of CREB examined by Western blotting, enzyme-linked immunosorbant assay, and immunocytochemistry. The translocation of CaM from the cytosol to the nucleus was also examined after depolarization. Cells were depolarized and lysed and fractionated by centrifugation to determine the amount of CaM translocated to the nucleus. CaM was localized by immunocytochemistry and quantitated by Western blotting and imaging. Before and during KCl depolarization, cells were exposed to isoflurane, isoflurane plus Bay K 8644, nitrendipine, and -conotoxin GVIa, respectively.

RESULTS: P-CREB increased after KCl depolarization. The increase of P-CREB peaked at depolarization duration of 30 s. The increase in P-CREB formation was inhibited by nitrendipine, but not -conotoxin, and by isoflurane in a concentration-dependent fashion. Pretreatment with the L-type Ca²⁺ channel agonist, Bay K 8644, attenuated the inhibition of P-CREB formation by isoflurane. CaM presence in the nucleus occurred after KCl depolarization. CaM translocation was inhibited by nitrendipine and attenuated by isoflurane. Bay K 8644 pretreatment decreased the isoflurane inhibition of CaM translocation to the nucleus.

CONCLUSIONS: Our data demonstrate that isoflurane inhibits CaM translocation and P-CREB formation. This most likely occurs through isoflurane inhibition of Ca²⁺entry through L-type Ca²⁺ channels.

METHODS: Experiment 1 investigated whether wearing a HMD would affect how quickly anesthesiologists detect events, and whether the focus setting of the HMD (near or far) makes any difference. Twelve anesthesiologists provided anesthesia in three naturalistic scenarios within a simulated operating theater environment. There were 24 different events that occurred either on the patient monitor or in the operating room. Experiment 2 investigated whether anesthesiologists physically constrained by performing a procedure would detect patient-related events faster with a HMD than without. Twelve anesthesiologists performed a complex simulated clinical task on a part-task endoscopic dexterity trainer while monitoring the simulated patient’s vital signs. All participants experienced four different events within each of two scenarios.

RESULTS: Experiment 1 showed that neither wearing the HMD nor adjusting the focus setting reduced participants’ ability to detect events (the number of events detected and time to detect events). In general, participants spent more time looking toward the patient and less time toward the anesthesia machine when they wore the HMD than when they used standard monitoring alone. Participants reported that they preferred the near focus setting. Experiment 2 showed that participants detected two of four events faster with the HMD, but one event more slowly with the HMD. Participants turned to look toward the anesthesia machine significantly less often when using the HMD. When using the HMD, participants reported that they were less busy, monitoring was easier, and they believed they were faster at detecting abnormal changes.

CONCLUSIONS: The HMD helped anesthesiologists detect events when physically constrained, but not when physically unconstrained. Although there was no conclusive evidence of worsened inattentional blindness, found in aviation, the perceptual properties of the HMD display appear to influence whether events are detected. Anesthesiologists wearing HMDs should self-adjust the focus to minimize eyestrain and should be aware that some changes may not attract their attention. Future areas of research include developing principles for the design of HMDs, evaluating other types of HMDs, and evaluating the HMD in clinical contexts.

METHODS: Infusion sets differing in length, dead space volume, and presence of an ARV were assessed. Three drugs were infused simultaneously through different access points, and their concentrations were obtained using UV spectrophotometric analysis of the effluent. Different infusion configurations were compared by assessing (1) the amount of drug delivered to the patient per unit of time, (2) the mean amount of drug delivered to the patient per unit of time during the steady-state infusion (mass flow rate plateau), and (3) flow change efficiency calculated from the ratio of the area under the experimental instant mass flow rate curve to the area corresponding to theoretical instant mass flow rate curve.

RESULTS: Infusion sets with lower dead space volumes offered significantly higher flow change efficiency (53.0% ± 15.4% with a dead space volume equal to 0.046 mL 5 min after the start of infusion) than infusion sets with higher dead space volume (5.6% ± 8.2% with a dead space volume equal to 6.16 mL), whatever the flow rate changes. Even in case of large dead space volumes, the presence of an ARV significantly increased the mass flow rate plateau (from 92.4% to 99.3% of the theoretical plateau without and with the presence of an ARV, respectively).

CONCLUSIONS: Multi-infusion therapy induces perturbation in drug delivery. These perturbations (lag time, backflow, and bolus) could be reduced by using infusion sets including very low dead space volume and an ARV.

METHODS: We evaluated drug delivery via a standard pediatric 8-cm, 4-F double-lumen catheter. One syringe pump infused normal saline as the carrier fluid through a limb of a Y-piece connected to the catheter’s 22-gauge distal lumen. Through the other limb of the Y-piece, a second syringe pump infused methylene blue, the model drug, at a constant rate of 0.5 mL/h. The volume delivered was collected every minute for quantitative analysis. We compared 2 mL/h and 12 mL/h total flow rates to mimic volume delivery to a 3-kg infant, and priming of the Y-piece with the model drug, to mimic resumption of a stopped drug infusion, versus no priming, to mimic a new infusion. Drug pump system start-up performance was measured to estimate this factor’s contribution to infusion onset profiles.

RESULTS: When initiating a new infusion of the model drug, the time to steady-state delivery at the catheter’s end varied significantly among the studied scenarios as measured by the time to reach half of the targeted dose (t₅₀). Onset of delivery with a low total flow was much slower (t₅₀ = 23.5 ± 2.1 min) than with the high flow rate (t₅₀ = 15.7 ± 2.9 min). Priming the drug limb of the connecting Y-piece with methylene blue substantially shortened the time to steady state (low flow t₅₀ = 12.7 ± 0.6 min, high flow t₅₀ = 5.2 ± 0.8 min). Time to cessation of drug delivery to the end of the catheter after stopping the drug pump was substantially shorter using the high carrier flow rate (t₅₀ = 3 ± 0.5 min) compared with the low carrier flow rate (t₅₀ = 11.6 ± 0.8 min). Drug pump system start-up performance contributed to onset delay.

CONCLUSIONS: Current infusion techniques in the pediatric care setting can result in significant, unrecognized, and potentially hazardous delays in achieving delivery of intended drug doses to the patient. Total flow rate, priming of the infusion system, the dead volume of the fluid path, and the start-up performance of the infusion pump system contribute to delays in achieving targeted rates of drug delivery.

METHODS: Using New York hospital discharge data for the years 2001 through 2005, we identified all patients with a diagnosis of MH due to anesthesia using International Classification of Diseases, Ninth Revision, Clinical Modification code 995.86. MH prevalence was evaluated by demographic and clinical characteristics.

RESULTS: Of the 12,749,125 discharges from New York hospitals during the study period, 73 patients had a recorded diagnosis of MH due to anesthesia. Nearly three quarters of the MH patients were male and 71% were patients from emergency/urgent admissions. The estimated prevalence rate of MH was 0.96 (95% confidence interval [CI] 0.67–1.24) per 100,000 surgical discharges and 1.08 (95% CI 0.75–1.41) per 100,000 discharges in which there was any indication of exposure to anesthesia. The estimated prevalence of MH for males was 2.5 to 4.5 times the rate for females.

CONCLUSION: The prevalence of MH due to anesthesia in surgical patients treated in New York State hospitals is approximately 1 per 100,000. MH risk in males is significantly higher than in females.

METHODS: Using the Healthcare Cost and Utilization Project State Inpatient Databases files, we identified all discharge records for labor and delivery from New York hospitals between 2002 and 2005. We then identified women who experienced any recorded anesthesia-related complication during labor and delivery as determined by International Classification of Diseases, Ninth Revision, Clinical Modification codes. The incidence of anesthesia-related complications was calculated by demographic and clinical characteristics. Multivariate logistic regression was performed to assess risk factors of anesthesia-related complications.

RESULTS: Of the 957,471 deliveries studied, 4438 (0.46%) had at least one anesthesia-related complication. The majority (55%) of anesthesia-related events occurring during labor and delivery were spinal complications, followed by systemic complications (43%) and overdose or adverse effects (2%). Multivariate logistic regression revealed five risk factors of anesthesia-related complications: cesarean delivery (odds ratio [OR] 2.51, 95% confidence interval [CI] 2.36-2.68), rural area (OR 1.33, 95% CI 1.21-1.46), Charlson-Deyo Comorbidity Index ≥1 (OR 1.47, 95% CI 1.28-1.69), Caucasian race (OR 1.37, 95% CI 1.24-1.52), and scheduled admission (OR 1.10, 95% CI 1.03-1.18). Anesthesia-related complications were associated with about a one-day increase in the average length of stay (3.89 ± 3.69 [mean ± sd] days vs 2.92 ± 2.38 days for deliveries without anesthesia-related complications, P < 0.0001) and a 22-fold increased risk of maternal mortality (OR 22.26, 95% CI 11.20-44.24).

CONCLUSION: The incidence of anesthesia-related complications during labor and delivery seems to be low but remains a cause of concern, particularly in women undergoing cesarean delivery, living in rural areas, or having preexisting medical conditions.

METHODS: All sequentially enrolled MO patients underwent preoperative polysomnography. Severity of OSA was quantified using AHI and the American Society of Anesthesiologists’ OSA severity scale. All patients had a standardized anesthetic that included positioning in the "ramped position" for direct laryngoscopy.

RESULTS: One hundred eighty consecutive patients were recruited, 140 women and 40 men. The incidence of OSA was 68%. The mean BMI was 49.4 kg/m². The mean AHI was 31.3 (range, 0-135). All the patients’ tracheas were intubated successfully without the aid of rescue airways by anesthesiology residents. Six patients required three or more intubation attempts, a difficult intubation rate of 3.3%. There was an 8.3% incidence of difficult laryngoscopy, defined as a Cormack and Lehane Grade 3 or 4 view. There was no relationship between NC and difficult intubation (odds ratio 1.02, 95% confidence interval 0.93-1.1), between the diagnosis of OSA and difficult intubation (P = 0.09), or between BMI and difficult intubation (odds ratio 0.99, 95% confidence interval 0.92-1.06, P = 0.8). There was no relationship between number of intubation attempts and BMI (P = 0.8), AHI (P = 0.82), or NC (P = 0.3). Mallampati Grade III or more predicted difficult intubation (P = 0.02), as did male gender (P = 0.02). Finally, there was no relationship between Cormack and Lehane grade and BMI (P = 0.88), AHI (P = 0.93), or OSA (P = 0.6). Increasing NC was associated with difficult laryngoscopy but not difficult intubation (P = 0.02).

CONCLUSIONS: In MO patients undergoing bariatric surgery in the "ramped position," there was no relationship between the presence and severity of OSA, BMI, or NC and difficulty of intubation or laryngoscopy grade. Only a Mallampati score of 3 or 4 or male gender predicted difficult intubation.

METHODS: Initially, the release of sevoflurane from the surgical site was measured during 35 tumorectomies starting from opening to closure of the dura. Volatile anesthetic absorbers were placed at three detection sites: 1) the surgeon’s breathing zone, 2) the anesthesiologist’s breathing zone, and 3) the farthest corner of the operation room. In the second sampling series that included 16 patients, the detector that had been in the corner of the operating room in the first series was now placed in the vicinity of the patient’s mouth (within 5 cm). Sevoflurane captured by the absorbers was quantified by an independent chemist using chromatography.

RESULTS: Absorbers in the surgeon’s breathing zone (0.24 ± 0.04 ppm) captured a significantly lower amount of sevoflurane compared with absorbers in the anesthesiologist’s breathing zone (1.40 ± 0.37 ppm) and comparable with that in the farthest corner of the operation room (0.25 ± 0.07 ppm). There was no correlation between the amount of absorbed sevoflurane and the size of craniotomy window, even when adjusting for the variation in duration of surgery. In the second series of sampling, absorbers in the proximity of the patient’s mouth captured the highest amount of sevoflurane (1.54 ± 0.55 ppm), followed by the anesthesiologist’s (1.14 ± 0.43 ppm) and the surgeon’s (0.15 ± 0.05 ppm) breathing zones.

CONCLUSIONS: The close proximity of the surgeon’s breathing zone to the craniotomy window does not appear to be a source of increased exposure to sevoflurane. The observed higher exposure of the anesthesiologist to sevoflurane in the operating room environment warrants further exploration.

METHODS: In this post hoc analysis, we assessed predictive parameters for neurological recovery after successful CPR. The original study was designed as a blinded, randomized, prospective, controlled, multicenter clinical trial.

RESULTS: We identified 1166 prehospital cardiac arrest patients being treated with advanced cardiac life support. Seven hundred eighty-six of 1166 patients (67.4%) died at the scene and 380 of 1166 (32.6%) were brought to the hospital. Two hundred sixty-five of 1166 patients (22.7%) died in the hospital. One hundred fifteen of 1166 (9.8%) were discharged from the hospital and 92 of the 115 patients (80%) could be followed-up. Good cerebral performance was regained by 54% of discharged patients (50 of 92 patients). In 46% of patients (42/92), unconsciousness or severe disability remained. Ventricular fibrillation was more likely to have occurred in patients with good neurological recovery (42/50 = 84.0%), whereas asystole was more likely in patients with poor neurological recovery (9/42 = 21.4%). A score was developed to predict the probability of death using logistic regression analysis. Predicting death in the hospital revealed a sensitivity of 99.8% (953/955), but only a specificity of 2.9% (3/104; threshold 0.5). Predicting survival until discharge from the hospital revealed a sensitivity of 99% (103/104), but only a specificity of 8% (72/955; threshold 0.99). A receiver operating characteristic curve yielded an area under the curve of 0.795 (0.751-0.839) at a confidence interval of 95%.

CONCLUSION: For out-of-hospital patients with cardiac arrest, parameters documented in the field did not allow accurate prediction of hospital survival.

METHODS: Anesthetized Sprague-Dawley rats were exposed to 1 min of asphyxial cardiac arrest. Resuscitation was standardized and consisted of chest compressions, oxygen (Fio₂ 1.0), and IV epinephrine 30 µg/kg (Series 1) and 10 µg/kg (Series 2). Left ventricular function was assessed by echocardiography (Series 1), and animals were randomized to receive either 5 cm H₂O PEEP or zero PEEP at commencement of CPR and throughout resuscitation. Survival was defined as the presence of a spontaneous circulation 60 or 120 min (Series 2) after initial resuscitation.

RESULTS: There were no baseline differences between the groups. In Series 1, administration of 5 cm H₂O PEEP (Fio₂ 1.0 and 0.21) was associated with improved survival compared with zero PEEP (7/9 and 6/6 vs 0/9, P < 0.01 and <0.001, respectively). Application of 5 cm H₂O PEEP (Fio₂ 1.0) increased left ventricular end-diastolic area, systemic oxygenation, and functional residual capacity. Use of PEEP during CPR did not adversely affect left ventricular systolic function or arterial blood pressure. The outcome differences were not due to increased oxygenation because the rank order of survival was 5 cm H₂O PEEP (Fio₂ 1.0) 5 cm H₂O PEEP (Fio₂ 0.21) > zero PEEP (Fio₂ 1.0), whereas the rank order of Pao₂ was 5 cm H₂O PEEP (Fio₂ 1.0) > 5 cm H₂O PEEP (Fio₂ 0.21) zero PEEP (Fio₂ 1.0). In an additional series in which epinephrine 10 µg/kg was used (Series 2), the survival was 100% with no beneficial effects of PEEP.

CONCLUSION: In asphyxial cardiac arrest in a small rodent model, continuous application of PEEP (5 cm H₂O) during and after CPR had beneficial effects on survival that were independent of oxygenation and without adverse cardiovascular effects.

METHOD: Thirty-two subjects (14 men and 18 women) were studied. We constructed pressure-flow relationships to evaluate P_CRIT and R_US during midazolam anesthesia. The midazolam anesthesia was induced with an initial dose of midazolam (0.07–0.08 mg/kg bolus) and maintained by midazolam infusion (0.3–0.4 µg · kg^–1 · min^–1), and the level of anesthesia was assessed by Ramsay score (Level 5) and Observer’s Assessment of Alertness/Sedation score (Level 2). Polysomnographic and hemodynamic variables were monitored while nasal pressure (via mask), inspiratory air flow (via pneumotachograph), and genioglossal electromyograph (EMG_GG) were recorded. P_CRIT was obtained in both the passive condition, under conditions of decreased EMG_GG (passive P_CRIT), and in an active condition, whereas EMG_GG was increased (active P_CRIT). The difference between the active P_CRIT and passive P_CRIT (P_{CRIT P – A}) was calculated in each subject to determine the compensatory neuromuscular response.

RESULTS: The difference between the active P_CRIT and passive P_CRIT (P_{CRIT A – P}) was significantly greater in women than in men (4.6 ± 2.8 cm H₂O and 2.2 ± 1.7 cm H₂O, respectively; P < 0.01), suggesting greater compensatory neuromuscular response to upper airway obstruction independent of arousal.

CONCLUSION: We demonstrate that the arousal-independent compensatory neuromuscular responses to upper airway obstruction during midazolam anesthesia were partially maintained in women, and that gender may be a major determinant of the strength of compensatory responses during anesthesia.

METHODS: In this double-blind study, 178 patients were randomly assigned to receive a preload of 500 mL of hydroxyethyl starch over a period of 15–20 min before initiation of spinal anesthesia (n = 90) or an identical fluid bolus of hydroxyethyl starch starting at the time of identification of cerebrospinal fluid (n = 88). Vasopressors (ephedrine or phenylephrine) were administered if systolic arterial blood pressure decreased less than 80% of the baseline pressure and <100 mm Hg, or with smaller decreases in blood pressure if accompanied by nausea, vomiting, or dizziness. The primary outcome was the incidence of hypotension (defined as the administration of at least one dose of vasopressor).

RESULTS: There was no significant difference between the groups in the incidence of hypotension (68% in preload group and 75% in coload group, 95% confidence interval of difference –6%–20%; P = 0.28), doses of ephedrine and phenylephrine, and number of vasopressor unit doses. The incidence of severe hypotension (systolic blood pressure <80 mm Hg) was 16% in the preload group and 22% in the coload group (P = 0.30). There were no differences in the incidence of nausea and/or vomiting, or neonatal outcome between the groups.

CONCLUSION: There was no difference in the incidence of hypotension in women who received colloid administration before the initiation of spinal anesthesia compared with at the time of initiation of anesthesia. Both modalities are inefficient as single interventions to prevent hypotension.

METHODS: Using a prospective, observational format, pregnant patients were examined for multiple potential risk factors for neuraxial technique difficulty, including current body mass index, ability to palpate spinous processes, maximum back flexion, scoliosis, and experience of the practitioner. Neuraxial technique difficulty was then assessed using two measures: 1) the number of needle passes needed to reach the desired space, and 2) the placement time from skin infiltration to either spinal injection or epidural catheter threading. Predictors of total needle passes were determined by fitting the data to a generalized linear model with negative binomial error. Predictors of neuraxial anesthetic time were determined by fitting a linear model to the log of neuraxial anesthetic placement time. A survival model was used to account for bias introduced when attending physicians intervened in resident physician procedures.

RESULTS: Neuraxial procedures in 427 pregnant patients were studied. For both the number of needle passes and the neuraxial anesthetic placement time, the significant predictors of difficulty were the practitioner’s ability to palpate the patient’s bony landmarks and the patient’s ability to flex her back. Obesity, as measured by body mass index, was not an independent predictor of either end point. Obesity did, however, strongly predict both the ability to palpate landmarks and flex the back.

CONCLUSIONS: Despite concerns that obesity may cause difficulty with neuraxial technique, some obese patients have surprisingly easy neuraxial block placements. When approaching any neuraxial anesthetic in a pregnant patient, and especially in the obese parturient, back flexion and landmark palpation predict neuraxial technique difficulty.

METHODS: We retrospectively reviewed all recorded surgical cases of 2 large European teaching hospitals from 2005 to 2008, involving 85,312 cases and 92,099 h in total. Surgical times tended to be skewed and bounded by some minimally required time. We compared the fit of the normal distribution with that of 2- and 3-parameter lognormal distributions for case durations of a range of Current Procedural Terminology (CPT)-anesthesia combinations, including possible surgeon effects. For cases with very few observations, we investigated whether supplementing the data information with surgeons’ prior guesses helps to obtain better duration estimates. Finally, we used best fitting duration distributions to simulate the potential efficiency gains in OR scheduling.

RESULTS: The 3-parameter lognormal distribution provides the best results for the case durations of CPT-anesthesia (surgeon) combinations, with an acceptable fit for almost 90% of the CPTs when segmented by the factor surgeon. The fit is best for surgical times and somewhat less for total procedure times. Surgeons’ prior guesses are helpful for OR management to improve duration estimates of CPTs with very few (<10) observations. Compared with the standard way of case scheduling using the mean of the 3-parameter lognormal distribution for case scheduling reduces the mean overreserved OR time per case up to 11.9 (11.8–12.0) min (55.6%) and the mean underreserved OR time per case up to 16.7 (16.5–16.8) min (53.1%). When scheduling cases using the 4-parameter lognormal model the mean overutilized OR time is up to 20.0 (19.7–20.3) min per OR per day lower than for the standard method and 11.6 (11.3–12.0) min per OR per day lower as compared with the biased corrected mean.

CONCLUSIONS: OR case scheduling can be improved by using the 3-parameter lognormal model with surgeon effects and by using surgeons’ prior guesses for rarely observed CPTs. Using the 3-parameter lognormal model for case-duration prediction and scheduling significantly reduces both the prediction error and OR inefficiency.

METHODS: (A) Three years of operating room (OR) information system data were analyzed. Dependent variables were the earliest times when the numbers of ORs running were always ≤6 ORs, ≤4 ORs, and ≤2 ORs. We progressively built linear regression models for each of the three dependent variables using day of the week, scheduled number of cases, scheduled hours of cases (including turnovers), and linear time trend. Calculations were repeated after excluding residuals. Calculations were repeated using regression trees. (B) Anesthesiologists were surveyed about their perceptions of the mean and 80th percentiles.

RESULTS: (A) For the three thresholds and two end points (mean and 80th percentile), differences among days of the week were as large as 45 min. Differences between end points for the same weekdays were as large as 245 min. Comparatively, additional knowledge about the number or hours of cases provided in the late afternoon on the working day before surgery reduced the mean absolute error by only 4.1–6.0 min. Results were insensitive to a variety of analytic methods. Information available more days before the day of surgery (e.g., 1 wk) would have had even less incremental predictive value. (B) The mean absolute error of anesthesiologists’ estimates for 80th percentiles was 60 min, principally because of underestimation of the 80th percentiles. More than half (69%, P = 0.0003) of anesthesiologists’ estimates for 80th percentiles had error >30 min, whereas errors of this magnitude were less for the mean (44%, P = 0.0004).

CONCLUSIONS: Historical data from OR or anesthesia information management systems, or from anesthesia billing systems, can be used months before staff scheduling to provide insight to anesthesia providers on respective calls. The data are useful because experience provides limited intuition. Updates on scheduled workload available closer to the day of surgery provided only marginal increases in knowledge over the use of historical data.

METHODS: After implantation of a high-density 8 x 8 electrode array in the visual cortex, the patterns of LFP and multiunit spike activity were recorded in rats during 0.5, 1.0, 1.5, and 2.0 minimum alveolar anesthetic concentration (MAC) enflurane anesthesia. These recordings were compared with computer simulations from a mean field model of neocortical dynamics. The neuronal effect of increasing enflurane concentration was simulated by prolonging the decay time constant of the inhibitory postsynaptic potential (IPSP). The amplitude of the excitatory postsynaptic potential (EPSP) was modulated, inverse to the neocortical firing rate.

RESULTS: In the anesthetized rats, increasing enflurane concentrations consistently caused the appearance of suppression pattern (>1.5 MAC) in the LFP recordings. The mean rate of multiunit spike activity decreased from 2.54/s (0.5 MAC) to 0.19/s (2.0 MAC). At high MAC, the majority of the multiunit action potential events became synchronous with the PED. In the theoretical model, prolongation of the IPSP decay time and activity-dependent EPSP modulation resulted in output that was similar in morphology to that obtained from the experimental data. The propensity for rhythmic seizure-like activity in the model could be determined by analysis of the eigenvalues of the equations.

CONCLUSION: It is possible to use a mean field theory of neocortical dynamics to replicate the PED pattern observed in LFPs in rats under enflurane anesthesia. This pattern requires a combination of a moderately increased total area under the IPSP, prolonged IPSP decay time, and also activity-dependent modulation of EPSP amplitude.

METHODS: To test whether preconditioning with sevoflurane induces rapid ischemic tolerance, New Zealand White male rabbits were randomly assigned to three groups. Animals in the Sev group received preconditioning with 3.7% sevoflurane (1.0 minimum alveolar anesthetic concentration) in 96% oxygen for 30 min, whereas animals in the O₂ group serving as controls inhaled only 96% oxygen for 30 min. The Sham group received the same anesthesia and surgical preparation but no preconditioning or spinal cord I/R. To evaluate the role of ERK activation in sevoflurane preconditioning, rabbits were randomly assigned to four groups. U0126, an ERK inhibitor, was administered IV 20 min before the beginning of preconditioning in the U0126 + O₂ and U0126 + Sev groups. Dimethylsulfoxide was administered IV at the same time in the vehicle + O₂ and vehicle + Sev groups. At 1 h after preconditioning, the animals were subjected to spinal cord I/R induced by infrarenal aorta occlusion. All animals were assessed at 48 h after reperfusion with modified Tarlov criteria, and the spinal cord segments (L5) were harvested for histopathological examination, TUNEL staining, and Western blot of phosphor-ERK1/2.

RESULTS: The animals in the Sev group had higher neurological scores and more normal motor neurons than those in the O₂ group (P < 0.01 for each comparison). Compared with vehicle + Sev group, the U0126 + Sev group had worse neurological outcomes, fewer viable neurons, more apoptotic neurons, and significantly decreased ERK1/2 phosphorylation (P ≤ 0.01 for each comparison). There were no significant differences in the outcomes among vehicle + O₂, U0126 + O₂, and U0126 + Sev groups.

CONCLUSIONS: This study demonstrates that sevoflurane preconditioning induces rapid tolerance to spinal cord I/R in rabbits, and the tolerance is possibly mediated through the activation of ERK. These data suggest that sevoflurane preconditioning might provide a new practical method for protecting perioperative spinal cord I/R.

METHODS: Nineteen exons covering major hotspots were chosen for the primary screening by polymerase chain reaction, denaturing high performance liquid chromatography, and confirmed by direct sequencing.

RESULTS: Three novel variants involving amino acid changes were identified in two unrelated families as Met2698Arg, Glu2724Lys in exon 51 and Leu2785Val in exon 53.

CONCLUSIONS: Three novel ryanodine receptor isoform 1 variants located either near or within the central domain might predispose carriers to MH.

METHODS: Ninety-one women received IV oxycodone or morphine before the end of laparoscopic hysterectomy and then continued with patient-controlled analgesia for 24 h postoperatively.

RESULTS: The accumulated oxycodone consumption was less (13.3 ± 10.4 mg vs 22.0 ± 13.1 mg, P = 0.001) than morphine. With oxycodone, the visual analog scale scores were significantly lower in the first hour postoperatively and sedation was less during the 24-h postoperative period, P = 0.006.

CONCLUSIONS: Oxycodone was more potent than morphine for visceral pain relief but not for sedation.

METHODS: We studied IVD degenerative changes with pain development after a 10-µL CFA injection into the L5-6 IVD of adult rats using behavioral, histologic, and biochemical studies. Serial histologic changes were analyzed to detect degenerative changes. Expression of calcitonin gene-related peptide (CGRP), prostaglandin E (PGE), and inducible nitric oxide synthase (iNOS) were determined using immunohistochemistry or real-time polymerase chain reaction as support data for pain development. In addition, CGRP immunoreactivity (ir) at the IVD was considered indirect evidence of neural ingrowth into the IVD.

RESULTS: There was a significant increase of the hindpaw withdrawal response in the CFA group until 7 wk postoperatively (P < 0.05). Histologic analyses revealed progressive degenerative changes of the disks without any damage in adjacent structures, including nerve roots. In the CGRP-ir staining study, the bilateral dorsal horns and IVD had positive ir after intradiscal CFA injection. CGRP mRNA expression was increased in the dorsal root ganglion (DRG) at 2 and 4 wk, whereas PGE and iNOS mRNAs were markedly increased at 2 wk. The increment of CGRP expression was higher in allodynic rats compared with nonallodynic rats.

CONCLUSION: Intradiscal CFA injection led to chronic disk degeneration with allodynia, which was suggested by pain behavior and expression of pain-related mediators. The increment of CGRP, PGE, and iNOS also suggest pain-related signal processing between the IVD and the neural pathway in this animal model. This animal model may be useful for future research related to the pathophysiology and development of novel treatment for spine-related pain.

METHODS: Mechanical hypersensitivity was produced by injection of carrageenan (300 µg/20 µL) into the tibiotarsal joint of the right hind leg. The mechanical pain threshold was assessed by von Frey filaments (0.064-110 g). EM1 (30, 100, and 200 µg), KYNA (30, 100, 200, and 400 µg), and their combinations in a fixed-dose ratio (1:1) were injected into the inflamed joint, and the pain threshold was determined repeatedly for 75 min after the drug administrations.

RESULTS: Neither EM1 nor KYNA administered to the inflamed joint influenced the pain threshold at the noninflamed side. Both ligands produced dose-dependent antihyperalgesia, and the highest doses caused a prolonged effect. EM1 had higher potency (30% effective dose [ED₃₀] and 50% effective dose [ED₅₀] values were 112 µg [confidence interval {CI}: 80-146] and 167 µg [CI: 135-220], respectively) compared with KYNA (ED₃₀ and ED₅₀ values were 204 µg [CI: 160-251] and 330 µg [CI: 280-407], respectively). The antinociceptive effect of EM1 was prevented by subcutaneous naltrexone pretreatment. The coadministration of EM1 with KYNA caused an enhanced and/or prolonged antinociceptive effect. The ED₃₀ and ED₅₀ values of the combination were 141 µg [CI: 83-182] and 231 µg [CI: 190-293], respectively, which did not differ significantly from the theoretically additive values (ED₃₀ and ED₅₀ values were 145 µg [CI: 68-237] and 220 µg [CI: 144-230], respectively), thus the interaction between these ligands is additive. None of the treatments caused any sign of side effects.

CONCLUSION: Peripherally administered endogenous opioid agonist and NMDA receptor antagonist ligands might be beneficial in inflammatory pain. Because both drugs barely cross the blood-brain barrier, their local administration causes no central side effects.

METHODS: Mice received PSL; pERK1/2 (p44/42) in sciatic nerve was measured by both Western blotting and immunohistochemistry. U0126 (an ERK kinase inhibitor) was injected twice, an intraneural injection (20 nmol/2 µL) 30 min before PSL, and a perineural injection (20 nmol/10 µL) on Day 1 after PSL. Thermal hyperalgesia and tactile allodynia induced by PSL were evaluated by the thermal paw withdrawal test and the von Frey test, respectively.

RESULTS: As measured by Western blotting, in sham-operated mice, the levels of pERK1/2 in sciatic nerve were constant and the same as those in naive mice across Days 1-14. In PSL-operated mice, a significant increase in pERK1/2 was observed on Day 1 after PSL and persisted until Day 3. As measured by immunohistochemistry, immunoreactivity of pERK1/2 in PSL-operated sciatic nerve was markedly increased in comparison with that in sham-operated sciatic nerve on Day 1 after PSL. In the sciatic nerve on Day 1 after PSL, as indicated by double immunostaining, the increased immunoreactivity of pERK1/2 was colocalized with glial fibrillary acidic protein (GFAP), a marker of Schwann cells, but not F4/80, a marker of macrophages. PSL-induced thermal hyperalgesia was significantly attenuated by treatment with U0126 on Days 3, 7, and 14 after PSL. The PSL-induced tactile allodynia was also significantly attenuated by treatment with U0126 on Days 7 and 14 after PSL.

CONCLUSION: Activation of ERK in Schwann cells of the injured peripheral nervous system may play an important role in the development of neuropathic pain. Our results suggest that pERK itself and ERK-related mediators are potential therapeutic targets for the treatment of neuropathic pain.

METHODS: Male Wistar rats were anesthetized with sevoflurane and administered morphine and antidepressant drugs, or saline, through intrathecal injection. The antinociceptive effect was evaluated using the thermal withdrawal test before and after drug administration. The time for the withdrawal reaction was expressed as percentage of maximum possible effect (MPE). Animals were also pretreated with yohimbine (a nonselective alpha2-adrenergic antagonist) and naloxone (a nonselective opioid antagonist) for mechanism of action studies. Pharmacologic interaction was evaluated using isobolographic analysis of simultaneous administration of fixed proportions of maprotiline and morphine.

RESULTS: Single intrathecal administration of morphine (2 µg), amitriptiline (125 µg), citalopram (144 µg), and maprotiline (1.25 µg) produced 51.6% ± 8.9%, 10.3% ± 3.2%, 33.8% ± 5.2%, and 48.5% ± 9.2% MPE, respectively. The antinociceptive effect of morphine was increased when combined with amitriptyline (91.3% ± 4.6% MPE) and maprotiline (86.9% ± 9.2% MPE) but not with citalopram (40.6% ± 4.6% MPE). Coadministration of maprotiline increased the antinociceptive duration of morphine by 4-fold (from 120 to 480 min), which was reversed by pretreatment with the -2 adrenoceptor inhibitor, yohimbine, and the mu-type opioid receptor antagonist, naloxone. Isobolographic analysis demonstrated a synergistic interaction between morphine and maprotiline.

CONCLUSIONS: Selective norepinephrine reuptake inhibitors can significantly increase the intensity and duration of morphine antinociceptive activity via both ₂-adrenergic and opioid receptors. This interaction was not observed with the selective serotonin inhibitor, citalopram.

METHODS: Twenty-four adult male rats were divided into four groups: control, formalin test, restricted control, and restricted formalin test. Ten percent formalin was injected subcutaneously into the left rear paw of the formalin test and restricted formalin test groups. The control and formalin test group rats were kept in a clear plastic chamber, whereas the restricted control and restricted formalin test group rats were kept in a modified-restraint, pipe-shaped chamber. All rats were killed after 25 min. Twelve sections of the lumbar spinal cord were processed for p-ERK immunohistochemistry using the avidin-biotin peroxidase method.

RESULTS: The number of p-ERK positive cells in the restricted formalin test group was significantly higher than in the other three groups in the ipsilateral-side superficial dorsal horn (P < 0.05). However, there was no significant difference between the formalin test group and the two control groups in pERK expression.

CONCLUSION: Licking decreased pERK of the spinal cord of the formalin test group. The findings suggested that licking attenuated the pain of the formalin test.

METHODS: In the isolated rat heart, cardiac arrest was induced by administration of equipotent doses of bupivacaine, ropivacaine, and mepivacaine, respectively, followed by cardiac perfusion with or without lipid emulsion (0.25 mL · kg^–1 · min^–1). Subsequently, the times from the start of perfusion to return of first heart activity and to recovery of heart rate and rate-pressure product (to 90% of baseline values) were assessed.

RESULTS: In all groups, lipid infusion had no effects on the time to the return of any cardiac activity. However, recovery times of heart rate and rate-pressure product (to 90% of baseline values) were significantly shorter with the administration of lipids in bupivacaine-induced cardiac toxicity, but not in ropivacaine- or mepivacaine-induced cardiac toxicity.

CONCLUSIONS: These data show that the effects of lipid infusion on LA-induced cardiac arrest are strongly dependent on the administered LAs itself. We conclude that lipophilicity of LAs has a marked impact on the efficacy of lipid infusions to treat cardiac arrest induced by these drugs.

METHODS: Sixty patients undergoing hand surgery were randomly and blindly divided into three groups. All groups received IVRA lidocaine (3 mg/kg) diluted with saline to a total volume of 40 mL. Group 1 received IVRA lidocaine plus IV saline, Group 2 received IVRA lidocaine and paracetamol (300 mg) admixture plus IV saline, and Group 3 received IVRA lidocaine plus IV paracetamol (300 mg). Sensory and motor block onset time, tourniquet pain, and analgesic use were assessed during operation. After tourniquet deflation, visual analog scale (VAS) scores at 1, 2, 4, 6, 12, and 24 h, the time to first analgesic requirement, total analgesic consumption in first 24 h, and side effects were noted.

RESULTS: Onset of motor block was shorter and recovery of motor and sensory block was significantly longer in Group 2 (P < 0.05). Intraoperative VAS scores at intraoperative 20, 30, and 40 min were significantly lower in Group 2 (P < 0.05). Intraoperative fentanyl consumption (78 ± 12, 58 ± 14, 78 ± 11 µg, respectively) and the number of patients who required fentanyl for tourniquet pain (13 patients, 3 patients, 9 patients, respectively) were significantly less in Group 2 (P < 0.05). Time to postoperative fentanyl administration was also prolonged (15 ± 6, 25 ± 5, 15 ± 4 min, respectively) in Group 2 (P < 0.05). The quality of surgical anesthesia was better in Group 2 (P < 0.05). Postoperative VAS scores and time of initial analgesic requirement were similar among groups; however, the total amount of diclophenac use was less in Group 2 (P < 0.05).

CONCLUSION: The addition of paracetamol during IVRA with lidocaine decreased tourniquet pain, increased anesthesia quality, and decreased postoperative analgesic consumption.

METHODS: Seventy-five patients scheduled for lower limb surgery under combined spinal-epidural anesthesia were randomly allocated to one of three groups receiving intrathecal bupivacaine, levobupivacaine, or ropivacaine. The dose of local anesthetic was varied using up-down sequential allocation technique. The dose for the first patient in each group was 8 mg, and the dosing increment was set at 1 mg. Subsequent doses in each group were determined by the outcome in the previous patient using success or failure of the spinal anesthesia as the primary end point. A success was recorded if a bilateral T12 sensory block to cold was attained within 20 min after intrathecal injection, and the surgery proceeded successfully until at least 50 min after the intrathecal injection without supplementary epidural injection. The ED₅₀ was calculated using the method of Dixon and Massey.

RESULTS: The ED₅₀s were 5.50 mg for bupivacaine (95% confidence interval [CI]: 4.90–6.10 mg), 5.68 mg for levobupivacaine (95% CI: 4.92–6.44 mg), and 8.41 mg for ropivacaine (95% CI: 7.15–9.67 mg) in intrathecal anesthesia. The relative anesthetic potency ratios are 0.97 (95% CI: 0.81–1.17) for levobupivacaine/bupivacaine, 0.65 (95% CI: 0.54–0.80) for ropivacaine/bupivacaine, and 0.68 (95% CI: 0.55–0.84) for ropivacaine/levobupivacaine.

CONCLUSION: This study suggests that in intrathecal anesthesia for lower limb surgery, ropivacaine is less potent than levobupivacaine and bupivacaine, whereas the potency is similar between levobupivacaine and bupivacaine.

METHODS: Sixteen young, healthy volunteers entered the study. Spectral analysis of heart rate and systolic blood pressure variability was performed before and 30, 60, 90, and 120 min after either right or left stellate ganglion block, separated by a 1 to 11/2-mo interval, with 6 mL of 1% mepivacaine. Shortly after each spectral analysis, baroreflex sensitivity was assessed with the head-up tilt test.

RESULTS: Baroreflex sensitivity, assessed by the head-up tilt test, was significantly attenuated at 30 min after either right or left stellate ganglion block (1.26 ± 0.18 to 0.46 ± 0.08 bpm/mm Hg, P < 0.05 and 1.17 ± 0.35 to 0.51 ± 0.13 bpm/min, P < 0.01, respectively). Fractal slopes reflecting the degree of self-similarity of fluctuations were significantly increased at 30 min after either right or left stellate ganglion block (right stellate ganglion block—heart rate; –1.08 ± 0.30 to –1.62 ± 0.22, P < 0.01; right stellate ganglion block—systolic blood pressure; –1.30 ± 0.80 to –2.40 ± 0.80, P < 0.05; left stellate ganglion block—systolic blood pressure; –1.20 ± 0.40 to –2.13 ± 0.50, P < 0.05). Fractal slope did not change after left stellate ganglion block with heart rate variability analysis.

CONCLUSIONS: Loss of complexity (status of being complex behavior) of both heart rate and systolic blood pressure variability, indicated by increased fractal slopes, is one mechanism in attenuating baroreflex sensitivity after stellate ganglion block.

Postoperative quadriparesis, although infrequent, can occur through different causes and mechanisms. Central progression of an interscalene block can produce acute or subacute quadriparesis depending on technical factors of the placement of the local anesthetic and its subsequent spread. The symptomatology and the imaging enabled us to refine the differential diagnoses and to exclude other causes of neurologic compromise.

METHODS: We performed a prospective, controlled, randomized animal study (male Lewis rats n = 44). The interventions we used were intraperitoneal injection of Escherichia coli LPS (10 mg/kg) or vehicle followed by either DA (25 µg/kg) or vehicle (four experimental groups). Blood and reticulocyte counts and variables of iron metabolism were measured at baseline and 3 and 14 days after interventions.

RESULTS: Animals treated with DA alone showed an eightfold increase in reticulocyte count from baseline on Day 3, whereas no increase was seen in animals administered LPS or LPS/DA. On Day 14, the red blood cell count and hemoglobin concentration had increased by approximately 10% from baseline (P < 0.001) in the DA group but had decreased after LPS on Days 3 and 14 (P < 0.05) and in animals administered LPS/DA. Consumption of iron was seen on Day 3 in the DA group but not after LPS or LPS/DA combined. Values of ferritin and transferrin did not change between groups.

CONCLUSION: LPS abolishes erythropoiesis and iron use evoked by DA and this is accompanied by a decrease in hemoglobin concentration and red blood cell concentration. Accordingly, endotoxin suppresses DAs ability to increase erythropoiesis.

METHODS: We compared the anticoagulant effect of 10 concentrations of fondaparinux added to plasma samples with normal range (n = 25, antithrombin 95.4% ± 9.2%) and low antithrombin (n = 22, antithrombin 45.5% ± 13.2%) levels, using the Heptest coagulation assay.

RESULTS: Heptest clotting time was shorter at any given fondaparinux concentration in the antithrombin-deficient samples, indicating less anticoagulant effect than in the group with normal antithrombin levels. At a high fondaparinux concentration, a saturation effect is observed with no further increase in Heptest clotting time. Addition of antithrombin concentrates results in a shift of the dose-response curve. When antithrombin concentrate was added, Heptest clotting time increased up to a fondaparinux concentration of 10 µg/mL.

CONCLUSIONS: In the conventional prophylactic and therapeutic dose range, not only treatment with antithrombin concentrates but also an increase in fondaparinux dose normalizes the anticoagulant effect. A saturation effect is observed at high fondaparinux concentrations. Higher levels of antithrombin lead to an exaggerated effect of fondaparinux on Heptest.

METHODS: Demographics, medical history, height, and weight were recorded for 1000 consecutive day surgery patients aged 2–12 yr. In addition, 1000 day surgery patients (age 2–12 yr) undergoing general endotracheal anesthesia were enrolled. After tracheal intubation, a 14–18F orogastric tube was inserted and gastric contents evacuated. Medications, fasting interval, GFV, pH, and emetic episodes were documented. Age- and gender-specific Center for Disease Control and Prevention growth charts (2000) were used to determine ideal body weight (IBW = 50th percentile) and to classify patients as lean/normal (BMI 25th–75th percentile), overweight (BMI ≥85th to <95th percentile), or obese (BMI ≥ 95th percentile).

RESULTS: Of all day surgery patients, 14.0% were overweight and 13.3% were obese. Obese children had lower GFV per total body weight (P < 0.001). When corrected for IBW, however, volumes GFV(IBW) were identical across all BMI categories (mean 0.96 mL/kg, sd 0.71; median 0.86 mL/kg, IQR 0.96). Preoperative acetaminophen and midazolam contributed to increased GFV(IBW) (P = 0.025 and P = 0.001). Lower GFV(IBW) was associated with ASA physical status III (P = 0.024), male gender (P = 0.012), gastroesophageal reflux disease (P = 0.049), and proton pump inhibitor administration (P = 0.018). GFV(IBW) did not correlate with fasting duration or age. Decreased gastric fluid acidity was associated with younger age (P = 0.005), increased BMI percentile (P = 0.036), and African American race (P = 0.033). Emesis on induction occurred in eight patients (50% of whom were obese, P = 0.052, and 75% of whom had obstructive sleep apnea, P = 0.061). Emesis was associated with increased ASA physical status (P = 0.006) but not with fasting duration. There were no pulmonary aspiration events.

CONCLUSIONS: Twenty-seven percent of pediatric day surgery patients are overweight/obese. These children may be allowed clear liquids 2 h before surgery as GFV(IBW) averages 1 mL/kg regardless of BMI and fasting interval. Rare emetic episodes were not associated with shortened fasting intervals in this population.

METHODS: One hundred children scheduled for elective surgery and general anesthesia were included. VAS-anxiety was measured at four timepoints and compared with both versions of State Spielbergers’ questionnaires (State-Trait Anxiety Inventory for Youth [STAIY] and State-Trait Anxiety Inventory for Children [STAIC]) and the modified Yale Preoperative Anxiety Scale. Children’s pain, parents’ anxiety, and parents’ proxy report of children’s anxiety were evaluated using VAS.

RESULTS: The correlation between STAIC and VAS-anxiety was significant on the day of discharge. Moreover, changes over time were not significant with STAIC, whereas VAS-anxiety was significantly sensitive to changes over time in the two groups of age (7–11 yr and 12–16 yr). A receiver operating characteristic curve, using modified Yale Preoperative Anxiety Scale as reference, determined a VAS-anxiety cutoff at 30 to identify high-anxiety groups. Pain levels were significantly higher when children were anxious (VAS ≥30) in the postoperative period. Moreover, children’s anxiety and pain were higher when parents were anxious.

CONCLUSION: VAS-anxiety is a useful and valid tool to assess perioperative anxiety in children aged 7–16 yr. The influence of children’s and parents’ anxiety on children’s postoperative pain suggests that VAS-anxiety should be recommended routinely for postoperative clinical practice to optimize anxiety and pain management.

METHODS: In this retrospective descriptive study, we reviewed the records of 52 children receiving dexmedetomidine and 30 children receiving propofol for anesthesia during MRI sleep studies between July 2006 and March 2008. Documentation of the severity of OSA by overnight polysomnography was available for 67 of the 82 subjects, who were analyzed separately. Data analyzed included demographics, severity of OSA, comorbidities, hemodynamic changes, use of artificial airways, additional airway maneuvers, and successful completion of the MRI scan.

RESULTS: Demographics, OSA severity by polysomnography, anesthetic induction, and baseline hemodynamics were comparable in both groups. An interpretable MRI sleep study was obtained for 98% of children in the dexmedetomidine group and 100% in the propofol group. Of 82 children, MRI sleep studies were successfully completed without the use of artificial airways in 46 children (88.5%) in the dexmedetomidine group versus 21 children (70%) in the propofol group (P = 0.03). An artificial airway was required to complete the study in five children (12%) in the dexmedetomidine group versus nine children (35%) in the propofol group (P = 0.06). Additional airway maneuvers (chin lift and shoulder roll) were required to complete the study in one child (2%) in the dexmedetomidine group and three children (10%) in the propofol group (P = 0.14). Children in the dexmedetomidine group experienced reductions in heart rate, whereas those in the propofol group experienced reductions in arterial blood pressure; these reductions were statistically, but not clinically, significant.

CONCLUSIONS: Dexmedetomidine provided an acceptable level of anesthesia for MRI sleep studies in children with OSA, producing a high yield of interpretable studies of the patient’s native airway. The need for artificial airway support during the MRI sleep study was significantly less with dexmedetomidine than with propofol. Dexmedetomidine may be the preferred drug for anesthesia during MRI sleep studies in children with a history of severe OSA and may offer benefits to children with sleep-disordered breathing requiring anesthesia or anesthesia for other diagnostic imaging studies.

METHODS: This was a prospective study conducted from December 2006 to June 2008. We enrolled 28 consecutive infants and neonates weighing <5 kg who underwent surgery for congenital heart disease. The patients were randomly assigned to a group in which STM was performed (STM group) or a group in which it was not performed (non-STM group). The cross-sectional area and diameter of the right IJV in the flat position and 10° Trendelenburg position with and without applying STM were measured. We determined time from first skin puncture to the following: (a) first blood back flow, (b) insertion of guidewire, and (c) insertion of catheter. Number of punctures, success rate, complications, and degree of IJV collapse during advancement of the needle (estimated as decrease of anteroposterior diameter during advancement of the needle compared with the diameter before advancement) were also examined.

RESULTS: STM significantly increased the cross-sectional area and the anteroposterior diameter of the IJV in both positions. The time required to insert the catheter was significantly shorter in the STM group, probably mainly due to a shorter guidewire insertion time. The degree of IJV collapse during advancement of the needle was much lower in the STM group.

CONCLUSIONS: STM facilitates IJV catheterization in infants and neonates weighing <5 kg by enlarging the IJV and preventing vein collapse.

Our work is based on data from a large trial of 4055 patients initially designed to quantify the effectiveness of combinations of antiemetic treatments for the prevention of PONV. This analysis uses propensity scores for case matching to ensure group comparability on baseline factors. Intraoperative NG tube use patients and perioperative NG tube use patients were respectively matched to nonuse patients on all available potential confounders.

Matched-pairs were identified using propensity scores for 1032 patients with or without intraoperative NG tube use and 176 patients with or without perioperative NG tube use. The incidences of PONV in the intraoperative group were 44.4% vs 41.5% (P = 0.35) with and without tube use, respectively, and 27.8% vs 31.3% (P = 0.61) in the perioperative group.

Our results provide evidence that routine use of a NG tube does not reduce the incidence of PONV.

METHODS: Twenty-one healthy volunteers aged 20–45 yr underwent propofol sedation using an effect-site target-controlled infusion system and two different dosing protocol schemes. In all, we increased propofol effect-site concentration (Ce) until loss of response to the ARM occurred. Subsequently, the propofol Ce was decreased either by a fixed percentage (20%, 30%, 40%, 50%, 60%, and 70%; fixed percentage protocol, n = 10) or by a linear deramping (0.1, 0.2, and 0.3 µg · mL^–1 · min^–1; deramping protocol, n = 11) until the ARM response returned. Consequently, the propofol Ce was maintained at the new target for a 6-min interval (Ce plateau) during which arterial samples for propofol determination were obtained, and a clinical assessment of sedation (Observer’s Assessment of Alertness/Sedation [OAA/S] score) performed. Each participant in the two protocols experienced each percentage or deramping rate of Ce decrease in random order. The assumption of steady state was tested by plotting the limits of agreement between the starting and ending plasma concentration (Cp) at each Ce plateau. The probability of response to the ARM as a function of propofol Ce, Bispectral Index (BIS) of the electroencephalogram, and OAA/S score was estimated, whereas the effect of the protocol type on these estimates was evaluated using the nested model approach (NONMEM). The combined effect of propofol Ce and BIS on the probability for ARM response was also evaluated using a fractional probability model (P_BIS/Ce).

RESULTS: The measured propofol Cp at the beginning and the end of the Ce plateau was almost identical. The Ce₅₀ of propofol for responding to the ARM was 1.73 (95% confidence interval: 1.55–2.10) µg/mL, whereas the corresponding BIS₅₀ was 75 (71.3–77). The OAA/S₅₀ probability for ARM response was 12.5/20 (12–13.4). A fractional probability (P_BIS/Ce) model for the combined effect of BIS and Ce fitted the data best, with an estimated contribution for BIS of 63%. Loss and return of ARM response occurred at similar sedation levels in individual subjects.

CONCLUSIONS: Reproducible ARM dynamics in individual subjects compares favorably with clinical and electroencephalogram sedation end points and suggests that the ARM could be used as an independent instrumental guide of drug effect during propofol-only sedation.

METHODS: Fifty-one obese patients, with a median (range) body mass index of 44 (34–72) kg/m², scheduled for laparoscopic gastric banding or gastric bypass under propofol-remifentanil anesthesia were randomized into three groups. The patients received rocuronium (0.6 mg/kg) based on IBW (IBW group, n = 17), IBW plus 20% of excess weight (corrected body weight [CBW]20% group, n = 17), or IBW plus 40% of excess weight (CBW40% group, n = 17). Propofol was administered as a bolus of 200 mg and an infusion at 5 mg · kg^–1 · h^–1 and remifentanil was administered at 1.0 µg · kg^–1 · min^–1, both according to CBW40%. Neuromuscular function was monitored with train-of-four nerve stimulation and acceleromyography. The primary end point was duration of action, defined as time to reappearance of the fourth twitch in train-of-four.

RESULTS: The median (range) duration of action was 32 (18–49), 38 (25–66), and 42 (24–66) min in the IBW, CBW20%, and CBW40% groups, respectively (P = 0.001 for comparison of the IBW and CBW40% group). There were no significant differences in onset time (85 vs 84 vs 80 s) or in intubation conditions 90 s after administration of rocuronium.

CONCLUSIONS: In obese patients undergoing gastric banding or gastric bypass, rocuronium dosed according to IBW provided a shorter duration of action without a significantly prolonged onset time or compromised conditions for tracheal intubation.

METHODS: We used bone marrow-derived DCs induced by granulocyte–monocyte-colony stimulating factor and interleukin (IL)-4 from bone marrow and analyzed the expression of costimulatory molecules (CD40, CD80, and CD86), major histocompatibility complex class II molecules, and secretion of IL-12p40. Furthermore, we evaluated the immune response in mixed cell cultures of DCs and T cells and the contact hypersensitivity response in a whole animal.

RESULTS: Ketamine suppressed the expression of CD40, CD80, and major histocompatibility complex class II molecules in DCs. DCs treated with ketamine also secreted less IL-12p40 and displayed greater endocytosis. In mixed cell cultures with CD4⁺ T cells and DCs, ketamine-treated DCs showed less propensity to stimulate the proliferation of CD4⁺ T cells and the secretion of interferon from CD4⁺ T cells. Furthermore, ketamine-treated DCs impaired the induction of a cell-mediated immune response.

CONCLUSION: Our findings suggest that ketamine inhibits the functional maturation of DCs and interferes with DC induction of Th1 immunity in the whole animal. These novel findings provide new insight into the immunopharmacological role of ketamine.

METHODS: In 7-day-old rats, we measured inspired and cerebral partial pressures of isoflurane at MAC as a function of duration of anesthesia. In 60-day-old rats, we measured inspired partial pressures of isoflurane at MAC as a function of duration of anesthesia. Finally, we determined the effect of administering 1 mg/kg naloxone and of delaying the initiation of the MAC determination (pinching the tail) on MAC in 7-day-old rats.

RESULTS: In 7-day-old rats, both inspired and cerebral measures of MAC decreased from 1 to 4 h. The inspired MAC decreased 56%, whereas the cerebral MAC decreased 33%. At 4 h, the inspired MAC approximated the cerebral MAC (i.e., the partial pressures did not differ appreciably). Neither administration of 1 mg/kg naloxone nor delaying tail clamping until 3 h reversed the decrease in MAC. In 60-day-old rats, inspired MAC of isoflurane was stable from 1 to 4 h of anesthesia.

CONCLUSIONS: MAC of isoflurane decreases over 1–4 h of anesthesia in 7-day-old but not in 60-day-old rats. Both pharmacodynamic and a pharmacokinetic components contribute to the decrease in MAC in 7-day-old rats. Neither endorphins nor sensory desensitization mediate the pharmacodynamic component.

METHODS: We studied 10 patients after elective thoracic or abdominal surgery with general anesthesia. Electroencephalogram, BIS, state entropy (SE), response entropy (RE), and ERPs were recorded immediately after surgery in the intensive care unit at Richmond Agitation-Sedation Scale (RASS) scores of –5 (very deep sedation), –4 (deep sedation), –3 to –1 (moderate sedation), and 0 (awake) during decreasing target-controlled sedation with propofol and remifentanil. Reference measurements for baseline levels were performed before or several days after the operation.

RESULTS: At baseline, RASS –5, RASS –4, RASS –3 to –1, and RASS 0, BIS was 94 [4] (median, IQR), 47 [15], 68 [9], 75 [10], and 88 [6]; SE was 87 [3], 46 [10], 60 [22], 74 [21], and 87 [5]; and RE was 97 [4], 48 [9], 71 [25], 81 [18], and 96 [3], respectively (all P < 0.05, Friedman Test). Both BIS and Entropy had high variabilities. When ERP N100 amplitudes were considered alone, ERPs did not differ significantly among sedation levels. Nevertheless, discriminant ERP analysis including two parameters of principal component analysis revealed a prediction probability P_K value of 0.89 for differentiating deep sedation, moderate sedation, and awake state. The corresponding P_K for RE, SE, and BIS was 0.88, 0.89, and 0.85, respectively.

CONCLUSIONS: Neither ERPs nor BIS or Entropy can replace clinical sedation assessment with standard scoring systems. Discrimination among very deep, deep to moderate, and no sedation after general anesthesia can be provided by ERPs and processed electroencephalograms, with similar P_Ks. The high inter- and intraindividual variability of Entropy and BIS precludes defining a target range of values to predict the sedation level in critically ill patients using these parameters. The variability of ERPs is unknown.

METHODS: In a prospective study, 380 patients who were scheduled for elective surgery were selected randomly and enrolled in the study. Before inducing anesthesia, the airways were assessed, and ULBT class, SMD, TMD, and IID determined. Laryngoscopic view according to the Cormack and Lehane grading system was determined after induction of anesthesia and Grades 3 and 4 defined as "difficult intubation." By using receiver operating characteristic analysis, the best cutoff points of the tests were calculated. Finally, sensitivity, specificity, positive and negative predictive values and accuracy of these tests and their combinations with the ULBT were calculated.

RESULTS: The prevalence of difficult intubation was 5% (n = 19). Class III ULBT, IID <4.5 cm, TMD <6.5 cm, and SMD <13 cm were defined as predictors of difficult intubation. There was no significant difference regarding difficult intubation based on gender (P < 0.05), whereas there were significant differences between the older tests and laryngeal view (P < 0.05, Mc-Nemar test). Specificity and accuracy of the ULBT were significantly higher than TMD, SMD, and IID individually (specificity was 91.69%, 82.27%, 70.64%, and 82.27%, respectively, and accuracy was 91.05%, 71.32%, 81.84%, and 76.58%, respectively). The combination of the ULBT with SMD provided the highest sensitivity.

CONCLUSION: We conclude that the specificity and accuracy of the ULBT is significantly higher than the other tests and is more accurate in airway assessment. However, the ULBT in conjunction with the other tests could more reliably predict easy laryngoscopy or intubation.

METHODS: Four hundred fifty consecutive adults (ASA PS I–II) undergoing tracheal intubation for elective surgery were randomly allocated for airway management with one of the three devices. Anesthesia induction for tracheal intubation consisted of fentanyl-propofol-rocuronium. An independent anesthesiologist used the Cormack-Lehane grading system to score an initial direct laryngoscopic view using a classic metal Macintosh blade. After subsequent positive-pressure ventilation using a face mask and an oxygen-sevoflurane mixture for 1 min, the trachea was intubated using one of the three VLSs. During intubation, the following data were collected: intubation time, number of intubation attempts, use of extra tools to facilitate intubation, and overall satisfaction score of the intubation conditions.

RESULTS: The trachea of every patient was intubated using the VLSs, and none of the patients required conversion to the classic Macintosh laryngoscope. All three VLSs offered equal or better view of the glottis as assessed by the mean Cormack-Lehane grade, compared with the traditional Macintosh laryngoscopy, including a larger viewing angle of the glottic entrance. The average intubation time was 34 ± 20 s for the GlideScope, 18 ± 12 s for the V-MAC Storz, and 38 ± 23 s for the McGrath VLS. Intubation with the Storz was faster (P < 0.05) than the other two VLS tested and necessitated fewer additional tools (P < 0.01), resulting in a higher first-pass successful intubation rate. A stylet had to be used in 7% of the patients in the Storz group versus about 50% of the patients when the other two VLS were used.

CONCLUSIONS: The trachea of a large proportion of patients with normal airways can be intubated successfully with certain VLS blades without using a stylet, although the three studied VLSs clearly differ in outcome. The Storz VLS displaces soft tissues in the fashion of a classic Macintosh scope, affording room for tracheal tube insertion and limiting the need for stylet use compared with the other two scopes. Although VLSs offer several advantages, including better visualization of the glottic entrance and intubation conditions, a good laryngeal view does not guarantee easy or successful tracheal tube insertion. We recommend that the geometry of VLSs, including blade design, should be studied in more detail.

METHODS: Two hundred patients were enrolled into the study. The patients were randomized into four groups: control, guidewire, slit endotracheal tube, and neck flexion with lateral neck pressure. The starting point of the procedure was the time when NG tube insertion was begun through the selected nostril. The end point was the time when there was either a successful insertion of the NG tube or a failure after two attempts. The success rate of the technique, duration of insertion procedure, and the occurrence of complications (bleeding, coiling, kinking, and knotting, etc.) were noted. ², analysis of variance, and Student's t-test were used to analyze the data.

RESULTS: Success rates were higher in all intervention groups compared with the control group. The time necessary to insert the NG tube was significantly longer in the slit endotracheal tube group. Kinking of the NG tube and bleeding were the most common complications.

CONCLUSION: The success rate of NG tube insertion can be increased by using a ureteral guidewire as stylet, a slit endotracheal tube as an introducer, or head flexion with lateral neck pressure. Head flexion with lateral neck pressure is the easiest technique that has a high success rate and fewest complications.

METHODS: This was a retrospective study in a university hospital and a general teaching hospital. Charts of patients who died during ICU stay or within 7 days after ICU discharge in 2005 were reviewed.

RESULTS: Of 2578 admitted patients, 356 patients (14%) died either in the ICU or within 7 days after ICU discharge. For 9 patients data were missing, leaving 347 patients for analysis. Seventy-seven patients (22%) died with full life support, 85 (25%) died while treatment was being withheld, and 185 (53%) patients died while treatment was being withdrawn. One or more changes in life support orders were noted in 266 patients (77%). Only 8% of the patients were recorded to be incapacitated at the time of the change. Patients’ preferences regarding life support were documented in less than one-quarter of cases. In approximately one third of cases, it was not documented which member(s) of the ICU team were involved in an end-of-life decision. In the documented cases, end-of-life decisions were made along with the patient (7%) or with the patient’s representatives (59%).

CONCLUSION: ICU nonsurvivors and patients who die shortly after ICU discharge predominantly die with orders to withhold or withdraw life support. Documentation on the decisions to forgo full life support is poor.

METHODS: After inducing experimental ALI by surfactant depletion, we studied two conditions in 10 female pigs: 1) LT volume ventilation with 6 mL/kg body weight, and 2) high tidal (HT) volume ventilation with 12 mL/kg body weight. Variables of gas exchange, hemodynamic, continuous cerebral tissue oxygen tension (p_tiO₂), cerebral microdialysis, and systemic cytokines were analyzed. After induction of ALI, data were collected at 2, 4, and 8 h. The primary end point was the change in p_tiO₂. For group comparisons, a t-test was used. A value of <0.05 was considered to indicate statistical significance.

RESULTS: At baseline and after induction of ALI, no differences between groups were found in p_tiO₂; however, p_tiO₂ was significantly lower in the HT group after 4 and 8 h. Pao₂ and Paco₂ showed no significant differences between the groups at all timepoints. Regarding cerebral microdialysis, a significantly higher level of extracellular lactate could be demonstrated after 2, 4, and 8 h in the HT group. The release of cytokines resulted in higher values for interleukin-6 and interleukin-8 in the HT group.

CONCLUSION: Protective ventilation with LT yielded a significant improvement in cerebral tissue oxygenation and metabolism compared to HT ventilation in a porcine model of ALI. There was dissociation between arterial and cerebral tissue oxygenation. Cerebral oxygenation and metabolism might have possibly been impaired by a more distinctive inflammatory response in the HT group.

METHODS: Five pigs (25–29.3 kg) were mechanically ventilated in supine position, and acute lung injury (ALI) was induced by surfactant depletion. After stabilization, BIPAP was initiated with lower continuous positive airway pressure equal to 5 cm H₂O and the higher continuous positive airway pressure titrated to achieve a tidal volume between 6 and 8 mL/kg. The depth of anesthesia was reduced, and when SB represented ≥20% of total minute ventilation, PSV and BIPAP + SB were each performed for 1 h (random sequence). Whole chest helical computed tomography was performed during end-expiratory pauses and functional variables were obtained. Pulmonary blood flow (PBF) was marked with IV administered fluorescent microspheres, and spatial cluster analysis was used to determine the effects of each ventilatory mode on the distribution of PBF.

RESULTS: ALI led to impairment of lung function and increase of poorly and nonaerated areas in dependent lung regions (P < 0.05). PSV and BIPAP + SB similarly improved oxygenation and reduced venous admixture compared with controlled mechanical ventilation (P < 0.05). Despite that, a significant increase of nonaerated areas in dependent regions with a concomitant decrease of normally aerated areas was observed during SB. In five of six lung clusters, redistribution of PBF from dependent to nondependent, better aerated lung regions were observed during PSV and BIPAP + SB.

CONCLUSIONS: In this model of ALI, the improvements of oxygenation and venous admixture obtained during assisted mechanical ventilation with PSV and BIPAP + SB were explained by the redistribution of PBF toward nondependent lung regions rather than recruitment of dependent zones.

METHODS: We examined Trauma Registry, quality management, and billing system records from July 1996 to June 2006 to determine the number of patients requiring intubation within 1 h of hospital arrival and to estimate the number requiring intubation with the first 24 h. We reviewed the medical record of each patient in either cohort who underwent a surgical airway access procedure (tracheotomy or cricothyrotomy) to determine the presenting characteristics of the patients and the reason they could not be orally or nasally intubated.

RESULTS: All intubation attempts were supervised by an anesthesiologist experienced in trauma patient care. Rapid sequence intubation with direct laryngoscopy was the standard approach throughout the study period. During the first hour after admission, 6088 patients required intubation, of whom 21 (0.3%) received a surgical airway. During the first 24 h, 10 more patients, for a total of 31, received a surgical airway, during approximately 32,000 attempts (0.1%). Unanticipated difficult upper airway anatomy was the leading reason for a surgical airway. Four of the 31 patients died of their injuries but none as the result of failed intubation.

CONCLUSIONS: In the hands of experienced anesthesiologists, rapid sequence intubation followed by direct laryngoscopy is a remarkably effective approach to emergency airway management. An algorithm designed around this approach can achieve very high levels of success.

METHODS: Open ETS was performed when clinically indicated in 11 children mechanically ventilated for sepsis or head injury. A total of 2800 pulmonary 1-min gas exchange measurements were recorded in 28 ETS instances for 50 consecutive minutes before and 50 min after the standardized procedure.

RESULTS: Pulmonary mechanics and indirect calorimetry did not differ between pre- and postsuction sets of measurements. Pre- and postsuction VO₂, VCO₂, dynamic airway resistance, dynamic compliance, and expiratory minute ventilation remained stable from 5 to 55 min after tracheal suctioning and did not differ among different ventilatory modes. Average paired differences of sequential pre- and postsuction VO₂, VCO₂, respiratory quotient, and resting energy expenditure were –0.6%, –1%, –0.1%, and –0.3%. Ratio differences between the first and the second periods of measurements (1–25 vs 26–50 sets of 1-min measurements) did not differ in the two groups.

CONCLUSIONS: Pulmonary mechanics and indirect calorimetry measurements are not influenced after uneventful open ETS in well-sedated patients. The E-COVX is able to reliably record spirometry and metabolic indices as early as 5 min after suctioning at different ventilator modes.

METHODS: PAP and lung weight were measured in isolated rat lungs during perfusion with Krebs-Henseleit hydroxyethyl starch buffer. Bupivacaine, ropivacaine, or procaine was added to the solution at concentrations of 10^–2–10^–7 mg/kg. ET-1 levels were measured in the perfusate by enzyme-immunoassay, and thromboxane A2 levels were assayed by radioimmunoassay. N-formyl-l-leucine-methionyl-l-phenylalanine was used to activate human polymorphonuclear neutrophils.

RESULTS: Bupivacaine, ropivacaine, and procaine significantly attenuated increases of PAP (P < 0.05) and resulted in a reduction of lung weight in these treatment groups compared with the sham group (P < 0.05). The long-acting anesthetics bupivacaine and ropivacaine (P < 0.05), but not procaine, reduced ET-1 levels, produced low inflammation rates, and did not affect lung structures at doses from 10^–3 to 10^–6 mg/kg.

CONCLUSION: Bupivacaine and ropivacaine attenuated N-formyl-l-leucine-methionyl-l-phenylalanine-induced PAP, reduced lung edema, and diminished ET-1 release. Lidocaine and mepivacaine are more effective in reducing PAP and edema formation, but long-acting local anesthetics also inhibit ET-1 depletion and therefore have increased anti-inflammatory properties.

METHODS: We conducted a 5-yr, longitudinal, cohort study involving 904 physicians consecutively admitted to 1 of 16 state PHPs between 1995 and 2001. This report analyzed a subset of the data involving the 102 anesthesiologists among the subjects and compared them with other physicians. The main outcome measures included relapse (defined as any unauthorized addictive substance use, including alcohol), return to anesthesiology practice, disciplinary actions, physician death, and patient harm.

RESULTS: Anesthesiologists were significantly less likely to enroll in a PHP because of alcohol abuse (odds ratio [OR] 0.4 [confidence interval {CI}: 0.2–0.6], P < 0.001) and much more likely to enroll because of opioid abuse (OR 2.8 [CI: 1.7–4.4], P < 0.001). Anesthesiologists had a higher rate of IV drug use, 41% vs 10% (OR 6.3 [CI: 3.8–10.7], P < 0.001). During similar periods of monitoring, anesthesiologists received more drug tests, 101 vs 82 (mean difference = 19 [CI: 3–35], P = 0.02); however, anesthesiologists were less likely to fail at least one drug test during monitoring, 11% vs 23% (OR 0.4 [CI: 0.2–0.9], P = 0.02). There was no statistical difference among rates of program completion, disciplinary actions, return to practice, or deaths, and there was no report of significant patient harm from relapse in any record.

CONCLUSIONS: Anesthesiologists in our sample treated and monitored for substance disorders under supervision of PHPs had excellent outcomes similar to other physicians, with no higher mortality, relapse rate, or disciplinary rate and no evidence in their records of patient harm. It is postulated that differences of study design account for contradictory conclusions from other reports.

METHODS: Data collected for each case at a six OR facility were room, date of surgery, time of patient entry into the OR, and time of patient exit from the OR. The number of simultaneous turnovers was calculated for each 1 min of 122 4-wk periods. Our end point was the reduction in the daily minutes of simultaneous turnovers exceeding the number of teams caused by the addition of a team.

RESULTS: Increasing from two turnover teams to three teams reduced the mean daily minutes of simultaneous turnovers exceeding the numbers of teams by 19 min. The ratio of 19 min to 8 h valued the time of extra personnel as 4.0% of the time of OR staff, surgeons, and anesthesia providers. Validity was suggested by other methods of analyses also suggesting staffing for three simultaneous turnovers. Discrete-event simulation showed that the reduction in daily minutes of turnover times from the addition of a team would likely match or exceed the reduction in the daily minutes of simultaneous turnovers exceeding the numbers of teams. Confidence intervals for daily minutes of turnover times achieved by increasing from two to three teams were calculated using successive 4-wk periods. The distribution was sufficiently close to normal that accurate confidence intervals could be calculated using Student's t distribution (Lilliefors' test P = 0.58). Analysis generally should use 13 4-wk periods as increasing the number of periods from 6 to 13 significantly reduced the coefficient of variation of the averages but not increasing the number of periods from 6 to 9 or from 9 to 13.

CONCLUSION: The number of simultaneous turnovers can be calculated for each 1 min over 1 yr. The reduction in the daily minutes of simultaneous turnovers exceeding the number of teams achieved by the addition of a turnover team can be averaged over the year's 13 4-wk periods to provide insight as to the value (or not) of adding an additional team.

METHODS: Fifteen healthy volunteers were studied during isocapneic hyperoxia and hypoxemia, and normoxic hypercapnea and hypocapnea. Absolute cerebral TOI and changes in oxy- and deoxyhemoglobin concentrations were measured using a NIRO 300 spectrometer. Changes in arterial oxygen saturation (Sao₂), ETco₂, heart rate, mean arterial blood pressure (MBP), and middle cerebral artery blood flow velocity (V_mca) were also measured during these physiological challenges. Changes in cerebral blood volume (CBV) were subsequently calculated from changes in total cerebral hemoglobin concentration.

RESULTS: Baseline TOI was 67.3% with an interquartile range (IQR) of 65.2%–71.9%. Hypoxemia was associated with a median decrease in TOI of 7.1% (IQR –9.1% to –5.4%) from baseline (P < 0.0001) and hyperoxia with a median increase of 2.3% (IQR 2.0%–2.5%) (P < 0.0001). Hypocapnea caused a reduction in TOI of 2.1% (IQR –3.3% to –1.3%) from baseline (P < 0.0001) and hypercapnea an increase of 2.6% (IQR 1.4%–3.7%) (P < 0.0001). Changes in Sao₂ (P < 0.0001), ETco₂ (P < 0.0001), CBV (P = 0.0003), and MBP (P = 0.03) were significant variables affecting TOI. Changes in V_mca (P = 0.7) and heart rate (P = 0.2) were not significant factors.

CONCLUSION: TOI is an easy-to-monitor variable that provides real-time, multisite, and noninvasive assessment of the balance between cerebral oxygen delivery and utilization. However, TOI is a complex variable that is affected by Sao₂ and ETco₂, and, to a lesser extent, by MBP and CBV. Clinicians need to be aware of the systemic and cerebral physiological changes that can affect TOI to interpret changes in this variable during clinical monitoring.

METHODS: Using isoflurane anesthesia, rats were subjected to a lethal hemorrhagic shock. After 5 min of no flow, hypothermia was induced with an aortic flush. Three groups were studied: ice-cold (IC) flush, room-temperature (RT) flush, and RT flush followed by minocycline treatment (RT-M). After 20 min of CA, resuscitation was achieved via cardiopulmonary bypass. Survival, Overall Performance Category (1 = normal, 5 = death), Neurologic Deficit Score (0%–10% = normal, 100% = max deficit), neuronal death (Fluoro-Jade C), and microglial proliferation (Iba1 immunostaining) in hippocampus were assessed at 72 h.

RESULTS: Rats in the IC group had lower tympanic temperature during CA versus other groups (IC, 20.9°C ± 1.3°C; RT, 28.4°C ± 0.6°C; RT-M, 28.3°C ± 0.7°C; P < 0.001). Although survival was similar in all groups (RT, 6/9; IC, 6/7; RT-M, 6/11), neurological outcome was better in the IC group versus other groups (Overall Performance Category: IC, 1 ± 1; RT, 3 ± 1; RT-M, 2 ± 1; P < 0.05; Neurologic Deficit Score: IC, 8% ± 9%; RT, 55% ± 19%; RT-M, 27% ± 16%; P < 0.05). Histological damage assessed in survivors showed selective neuronal death in CA1 and dentate gyrus, similar in all groups (P = 0.15). In contrast, microglial proliferation was attenuated in the IC group versus all other groups (P < 0.01).

CONCLUSIONS: Deeper levels of hypothermia induced by the IC versus RT flush resulted in better neurological outcome in survivors. Surprisingly, deep hypothermia attenuated microglial activation but not hippocampal neuronal death. Minocycline had modest benefit on neurologic outcome in survivors but did not attenuate microglial activation in brain. Our findings suggest a novel effect of deep hypothermia on microglial proliferation during exsanguination CA.

METHODS: Forty patients undergoing living donor liver transplantation were prospectively randomized into two groups. Patients in the ALB group (n = 20) received 5% human albumin. Patients in the HES group (n = 20) received third generation HES (6% HES 130/0.4). Total colloid administration was limited to 50 mL · kg^–1 · d^–1. The volume was given to maintain pulmonary artery occlusion pressure or central venous pressure between 5 and 7 mm Hg. If additional fluids were required, balanced crystalloid solution was used. Anesthetic and surgical techniques were standardized. Serum creatinine and cystatin C plasma levels were measured from arterial blood samples after induction of anesthesia, at the end of surgery, and on the first 4 postoperative days.

RESULTS: All 40 enrolled patients completed the study. Demographic and intraoperative variables were comparable in both groups. Postoperatively, the mean ± sd volume was 6229 ± 1140 mL and 4636 ± 1153 mL in HES and ALB groups, respectively (P = 0.003). There was significantly larger net cumulative fluid balance in the ALB group 1100 ± 900 mL compared with the HES group 3047 ± 2000 mL, P = 0.029. Serum creatinine, creatinine clearance, and cystatin C plasma levels showed no significant differences between the two groups. One patient in each group developed acute renal failure requiring renal replacement therapy.

CONCLUSION: The use of HES 130/0.4 as an alternative to human albumin resulted in equivalent renal outcome after liver transplantation.

METHODS: Groups of rats received daily morphine (10 mg/kg, IP) in combination with saline (10 µL/rat, intracerebroventricular [ICV]) or 1% Tween 80 (10 µL/rat, ICV) or minocycline (60, 120, and 240 µg/10 µL per rat, ICV) or riluzole (20, 40, 80 µg/10 µL per rat, ICV). Nociception was assessed using hotplate apparatus (55°C ± 0.5°C). Hotplate latency was recorded when the rat licked its hindpaw. Baseline latencies were determined once per day for each rat, then morphine (10 mg/kg) was injected. After 20 min, the above-mentioned drugs were administered and postdrug latency was measured 10 min after the injection of drugs or vehicles.

RESULTS: Results showed that ICV administration of minocycline and riluzole delayed morphine-induced tolerance. Morphine tolerance was complete after 8 days in the control groups but was complete in the groups treated with minocycline (120 µg/10 µL per rat) and riluzole (80 µg/10 µL per rat) on the 13th day. In addition, our results showed that minocycline and riluzole increased the total analgesic effect of morphine (area under the curve of the percentage of maximal possible effect values).

CONCLUSION: The effects of minocycline on nitric oxide and the glutamatergic system and the effect of riluzole on the glutamate system are potentially important mechanisms in delaying morphine-induced tolerance.

METHODS: All rats randomly received three injections: 1) a left subcutaneous hindpaw injection (0.2 mL with either carrageenan 2% w/v or saline), 2) a left sciatic block (0.2 mL with either bupivacaine 0.5% or saline), and 3) a systemic injection (subcutaneous interscapular with 0.2 mL with either bupivacaine 0.5% or saline). Local edema, thermal, and mechanical hyperalgesia as well as cerebrospinal fluid PGE2 concentration and COX-1 and COX-2 expression in the spinal cord in dorsal root ganglions were measured.

RESULTS: We confirmed that a bupivacaine block attenuates hyperalgesia and local inflammation in a model of inflammatory pain. This effect was associated with an inhibition of the increase in COX-2 expression induced by peripheral inflammation in dorsal root ganglions and cord. The subsequent production of PGE2 in cerebrospinal fluid was also impaired. Systemic bupivacaine did not modify either the hyperalgesia and local inflammation or COX expression.

CONCLUSION: These results constitute a key element strongly suggesting that local anesthetics act at a different level when administered systematically or via a nerve block.

METHODS: BZP was evaluated in rat preclinical models of inflammatory and neuropathic pain and compared with standard analgesics. Two models were used: the complete Freund’s adjuvant model of inflammatory pain and the spinal nerve ligation model of neuropathic pain. BZP was also evaluated in a motor coordination assay to assess its propensity for CNS side effects.

RESULTS: In preclinical models of chronic pain, BZP displayed efficacy comparable with that of leading analgesics. In the complete Freund’s adjuvant model, BZP produced reversal of hyperalgesia comparable with nonsteroidal antiinflammatory drugs, and in the spinal nerve ligation model, BZP produced reversal of allodynia comparable with gabapentin and mexiletine. Unlike the CNS penetrant compounds gabapentin and mexiletine, BZP did not induce any impairment of motor coordination.

CONCLUSIONS: These data suggest that a peripherally acting sodium channel blocker, preferentially acting through Na_v1.7, could provide clinical relief of chronic pain without the CNS side effects typical of many existing pain treatments.

METHODS: Hip drain fluid was collected at 24 h postsurgery from six patients undergoing standardized THA. In addition, venous blood was collected presurgery and 24 h postsurgery. Neutrophils were isolated, total RNA extracted, and a biotinylated cRNA probe generated. The probes were hybridized with a cDNA microarray containing approximately 100 oligonucleotide sequences representing various human cytokines/chemokines or receptor genes. Changes in gene expression seen in the microarray were verified by reverse transcription polymerase chain reaction.

RESULTS: In the microarray analysis of hip drain neutrophils, interleukin-1 receptor antagonist (IL1RN), interleukin-18 receptor 1 (IL18R1), macrophage migration inhibitory factor (MIF), and macrophage inflammatory protein 3 (CCL20) were upregulated, whereas interleukin-8 receptor β (IL8RB/CXCR2) was consistently downregulated, compared with presurgery blood neutrophils. All of these changes were confirmed by reverse transcription polymerase chain reaction.

CONCLUSION: There is a distinct cytokine gene expression profile in neutrophils at the THA surgical wound site at 24 h postsurgery when compared with that found in presurgery circulating neutrophils. Understanding these changes may allow us to knowledgeably manipulate neutrophil activity to reduce postoperative pain and inflammation without impairing wound healing.

METHODS: Twenty-one dogs were randomized to receive a 1-mL single intraspinal dose of one of the three solutions: saline (0.9%), amitriptyline (0.15%), or amitriptyline (0.3%). The dogs were evaluated clinically 1 h after awakening from anesthesia and 21 days later. At 21 days, all animals were killed, and histological sections of the spinal cord and surrounding meninges were retrieved for analysis.

RESULTS: All dogs recovered motor function, anal sphincter tone and sensibility. With the exception of one dog in the 0.15% amitriptyline group, all animals in both amitriptyline groups had marked adhesive arachnoiditis, which was absent in the control group. No evidence of direct neural damage was found on histological sections stained by glial fibrillary acidic protein technique in any of the study animals.

CONCLUSION: The intraspinal administration of amitriptyline to dogs even in low concentrations is strongly associated with the development of intense meningeal adhesive arachnoiditis and is not safe even at low concentrations for which there was no previous evidence of toxicity.

METHODS: After informed consent, 20 patients were recruited to receive sciatic catheter placement using the Raj approach. An insulated Tuohy needle was inserted perpendicular to skin at the midpoint of a line between the ischial tuberosity and greater trochanter. After sciatic nerve stimulation, a catheter was inserted 2–4 cm past the end of the needle and secured. The catheters were then incrementally injected with 30 mL of 1.5% mepivacaine. Twenty minutes after local anesthetic injection, sensory block was assessed using cold and pinprick tests, whereas motor block was assessed using a modified Bromage score. Complications and side effects were recorded.

RESULTS: In all instances, blocks were easy to perform and were successful. No major side effects or complications were noted.

CONCLUSION: Use of a simple landmark between easily identifiable bony structures enhances the simplicity and placement of a sciatic nerve catheter and is recommended for use in clinical practice.

METHODS: We performed a literature search using key words in the PubMed/ MEDLINE database. Seven articles that related to the effects of anesthesia on AVF construction, including sympathetic block, vein dilation, blood flow, adverse outcomes, or patency rates, comprised the sources for this review.

RESULTS: Significant vasodilation after regional block administration is seen in both the cephalic and basilic veins. These vasodilatory properties may assist with AVF site selection. In the intraoperative and postoperative periods, use of a regional block, compared with other anesthetic techniques, resulted in significantly increased fistula blood flow. The greater sympathetic block contributed to vessel dilation and reduced vasospasm. Use of regional techniques in AVF construction yielded shorter maturation times, lower failure rates, and higher patency rates.

CONCLUSION: Use of regional blocks may improve the success of vascular access procedures by producing significant vasodilatation, greater fistula blood flow, sympathectomy-like effects, and decreased maturation time. However, a large-scale, prospective, clinical trial comparing the different anesthetic techniques is still needed to verify these findings.

METHODS: The position of the lumbar triangle of Petit was assessed unilaterally in 26 cadaveric specimens relative to reliably palpable surface landmarks. In addition, a series of dissections were performed to explore the course of the nerves blocked by the TAP.

RESULTS: The mean distance from the midaxillary line along the iliac crest to the center of the base of the lumbar triangle of Petit at the level of the subcutaneous tissue and over the skin surface was 6.9 cm (range, 4.5–9.2 cm) and 9.3 cm (range, 4–15.1 cm), respectively. The center of the lumbar triangle of Petit was 1.4 cm above the iliac crest. The depth of the TAP at the lumbar triangle of Petit position was 0.5–4 cm and at the midaxillary line it was 0.5–2 cm. The average size of the lumbar triangle of Petit was 2.3 cm x 3.3 cm x 2.2 cm, with an average area of 3.63 ± 1.93 cm². The three cadaveric specimens we explored showed the nerves blocked by TAP passed lateral to the triangle. An incidental finding was that in 66% of specimens the lumbar triangle of Petit contained small branches of the subcostal artery.

CONCLUSIONS: The lumbar triangles of Petit found in the specimens in this study were more posterior than the literature suggests. The position of the lumbar triangle of Petit varies largely and the size is relatively small. The relevant nerves to be blocked had not entered the TAP in the specimens in this study at the point of the lumbar triangle of Petit. At the midaxillary line, however, all the nerves were in the TAP.

METHODS: Ninety patients undergoing cardiac surgery with cardiopulmonary bypass were randomized to receive either morphine (40 mg) or fentanyl (600 µg) as part of a standardized opioid-isoflurane anesthetic. Quality of recovery was assessed using the QoR-40 questionnaire administered preoperatively and daily on postoperative days 1-3. During the first three postoperative days, pain was measured using a 100-mm visual analog scale, and the use of IV and oral pain medications (morphine or acetaminophen/hydrocodone) was quantified. Hemodynamic variables, duration of tracheal intubation, postoperative febrile reactions, organ morbidities, and intensive care unit (ICU) and hospital length of stay were evaluated.

RESULTS: Compared with patients given fentanyl, those receiving morphine had higher global QoR-40 scores on postoperative days 1 (173 vs 160, P < 0.0001), 2 (174 vs 164, P < 0.0001), and 3 (177 vs 167, P < 0.001). Differences between the groups were observed in the QoR-40 dimensions of emotional state, physical comfort, and pain (all P < 0.01-0.0001). Postoperative visual analog scale pain scores, use of pain medication in the ICU and surgical ward, and postoperative febrile reactions were reduced significantly in the morphine group (all P < 0.01). No differences between the groups were noted in duration of tracheal intubation, ICU and hospital length of stay, or postoperative complications.

CONCLUSIONS: In patients undergoing elective cardiac surgery with cardiopulmonary bypass, postoperative quality-of-life measures and pain control during recovery were enhanced when morphine (40 mg) was administered intraoperatively as part of a balanced anesthetic technique compared with fentanyl.

METHODS: A comprehensive search was undertaken to identify all randomized trials of cell saver use during cardiac surgery. MEDLINE, Cochrane Library, EMBASE, and abstract databases were searched up to November 2008. All randomized trials comparing cell saver use and no cell saver use in cardiac surgery and reporting at least one predefined clinical outcome were included. The random effects model was used to calculate the odds ratios (OR, 95% confidence intervals [CI]) and the weighted mean differences (WMD, 95% CI) for dichotomous and continuous variables, respectively.

RESULTS: Thirty-one randomized trials involving 2282 patients were included in the meta-analysis. During cardiac surgery, the use of an intraoperative cell saver reduced the rate of exposure to any allogeneic blood product (OR 0.63, 95% CI: 0.43-0.94, P = 0.02) and red blood cells (OR 0.60, 95% CI: 0.39-0.92, P = 0.02) and decreased the mean volume of total allogeneic blood products transfused per patient (WMD –256 mL, 95% CI: –416 to –95 mL, P = 0.002). There was no difference in hospital mortality (OR 0.65, 95% CI: 0.25-1.68, P = 0.37), postoperative stroke or transient ischemia attack (OR 0.59, 95% CI: 0.20-1.76, P = 0.34), atrial fibrillation (OR 0.92, 95% CI: 0.69-1.23, P = 0.56), renal dysfunction (OR 0.86, 95% CI: 0.41-1.80, P = 0.70), infection (OR 1.25, 95% CI: 0.75-2.10, P = 0.39), patients requiring fresh frozen plasma (OR 1.16, 95% CI: 0.82-1.66, P = 0.40), and patients requiring platelet transfusions (OR 0.90, 95% CI: 0.63-1.28, P = 0.55) between cell saver and noncell saver groups.

CONCLUSIONS: Current evidence suggests that the use of a cell saver reduces exposure to allogeneic blood products or red blood cell transfusion for patients undergoing cardiac surgery. Subanalyses suggest that a cell saver may be beneficial only when it is used for shed blood and/or residual blood or during the entire operative period. Processing cardiotomy suction blood with a cell saver only during cardiopulmonary bypass has no significant effect on blood conservation and increases fresh frozen plasma transfusion.