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Anesth Analg 1999;88:1302
© 1999 International Anesthesia Research Society

PEDIATRIC ANESTHESIA

The Age-Related Effects of Epidural Lidocaine, With and Without Epinephrine, on Spinal Cord Blood Flow in Anesthetized Rabbits

Hervé Bouaziz, MD*,{dagger}, Naomitsu Okubo, MD{dagger}, Jean-Marc Malinovsky, MD{ddagger}, Dan Benhamou, MD§, Kamran Samii, MD{dagger}, and Jean Xavier Mazoit, MD, PhD{dagger}

*Département d'Anesthésie, Hôpital Central, Nancy; {dagger}Laboratoire d'Anesthésie, Université Paris-Sud, Faculté de Médecine du Kremlin-Bicêtre, Le Kremlin-Bicêtre; {ddagger}Département d'Anesthésie, Hôtel Dieu, Nantes; and §Département d'Anesthésie, Hôpital Antoine Béclère, Clamart, France

Address correspondence and reprint requests to Hervé Bouaziz, MD, Département d'Anesthésie, Hôpital Central, F-54035 Nancy Cedex, France.


   Abstract
Top
 Abstract
Introduction
 Methods
 Results
 Discussion
 References
 
The effect of epidural or spinal epinephrine when added to local anesthetics on spinal cord blood flow (SCBF)are controversial. We evaluated the effects of epidural lidocaine, with or without epinephrine, on spinal cord blood flow in young and adult rabbits receiving 2% plain lidocaine, 2% lidocaine with epinephrine (1:200,000), or saline epidurally. Colored microspheres were injected through the left ventricle 10 min before and 7.5 and 30 min after epidural injection. The organs (brain, heart, kidneys, and the L6-7 segment of the spinal cord) were analyzed for regional blood flow determination. A significant decrease in mean arterial pressure was observed after the administration of lidocaine, with or without epinephrine, in both adult and young animals compared with saline. SCBF did not change over time in adult rabbits. Conversely, a significant decrease in SCBF was observed in the two groups of young rabbits receiving lidocaine. This decrease correlated with the decrease in mean arterial pressure but did not correlate with the use of epinephrine. We conclude that any reduction in blood pressure occurring in pediatric patients receiving a combined epidural-general anesthetic may result in decreased SCBF.

Implications: In young rabbits, any decrease in blood pressure was followed by a decrease in spinal cord blood flow, a decrease that did not correlate to the use of epinephrine and was not observed in adult animals. These data suggest that blood pressure should be monitored closely to promptly treat any decrease in blood pressure when combined epidural-general anesthesia is used in children.


   Introduction
Top
 Abstract
 Introduction
Methods
 Results
 Discussion
 References
 
Serious complications related to regional anesthesia in adults have recently been described in a large prospective study including 103,730 patients (1). The rate of severe neurological complications after spinal or epidural anesthesia was reported to be 6:5000 or 2:5000 cases, respectively. Although a prospective study performed in pediatric patients failed to show any severe complications in >2500 regional anesthetics, another retrospective study reported a rate of approximately 1:5000 cases of severe neurological complications after epidural or caudal anesthesia in infants <3 mo of age (2,3). On magnetic resonance imaging scans performed in these cases, a hypersignal was constantly observed 6–12 days after epidural anesthesia. This hypersignal was interpreted as a potential sign of ischemia. Among the pathophysiological hypotheses reviewed, the addition of epinephrine to local anesthetics has been advanced. Indeed, the prolonged duration of analgesia observed when epinephrine is added to bupivacaine is proportionally longer in young infants than in adults (4). This may reveal an age-dependent sensitivity; therefore, it has been advised to reduce the usual concentration of epinephrine from 1:200,000 to 1:400,000 in infants (3). Nevertheless, there are conflicting data regarding the potential role of epinephrine in ischemic events occurring at the spinal cord level, inasmuch as caudal and epidural anesthesia in infants is usually performed with solutions containing epinephrine diluted 1:200,000. Moreover, the effect of epinephrine on the cord itself has never been compared in adult and young animals.

Because most regional anesthetic procedures in pediatric practice are performed in combination with general anesthesia, the purpose of this study was to determine the effect of epinephrine (5 µg/mL) added to epidural lidocaine on the spinal cord blood flow (SCBF) of anesthetized rabbits of varying ages.


   Methods
Top
 Abstract
 Introduction
 Methods
Results
 Discussion
 References
 
New Zealand White male rabbits 3 wk and 3 mo of age were studied according to a random block design. Care of the animals conformed to the recommendations of the Helsinski Declaration and to the guidelines of the French law for animal experiments. Anesthesia was induced with sodium pentobarbital 50 mg/kg intraperitoneally. A tracheotomy was performed, and the lungs were mechanically ventilated using a rodent ventilator (Harvard Apparatus, Les Ulis, France). Temperature was maintained within normal range using a homeothermic blanket control unit (Harvard Apparatus). Animals were placed in the prone position, and an epidural catheter (0.9 mm outer diameter, 900 mm long for adult rabbits and 0.63 mm outer diameter, 650 mm long for young rabbits) was inserted at the root of the tail and advanced in a cranial direction until the tip reached the L6-7 level, as described elsewhere (5). Thereafter, a 24-gauge Teflon catheter was inserted into the right femoral artery for measurement of arterial pressure and reference sampling during microsphere injection. Finally, a polyethylene catheter (PE50 in adult and PE10 in young rabbits) was inserted into the right carotid artery under direct vision and advanced until a left ventricular pressure tracing was obtained.

The femoral artery catheter was connected to a transducer to record arterial blood pressure. After a 15-min period to obtain stable baseline conditions, adult rabbits received either 1 mL of saline, 1 mL of 2% plain lidocaine (Astra, Courbevoie, France), or 1 mL of 2% lidocaine with epinephrine 1:200,000 (5 µg/mL) epidurally over 30 s. The 3-wk-old rabbits received 0.3 mL of the same solutions via the same route. Despite the difficulty in evaluating the sensory level under general anesthesia, we estimated the upper sensory level as previously described (5). One milliliter of blood was sampled via the femoral artery 30 min after epidural injection, and lidocaine was assayed in plasma using gas chromatography.

Two additional groups of young (n = 5) and adult (n = 6) rabbits receiving epinephrine 5 µg/mL in saline were also studied to determine the effect of epinephrine alone on SCBF.

To determine regional blood flow, 15.5 µm diameter colored microspheres (Dye-Trak; Triton Technology, Bioseb, France) were injected through the left ventricular catheter 10 min before and 7.5 and 30 min after epidural injection. Adult rabbits received 900,000 colored microspheres (yellow, white, and red injected in a random order) using a Harvard pump (Harvard Apparatus), whereas young rabbits received 225,000 colored microspheres (6,7). Simultaneous to microsphere injection, reference sampling from the femoral artery was begun at a constant rate of 0.84 mL/min for 75 s using a Harvard pump (Harvard Apparatus). Four milliliters of saline was infused thereafter to compensate for the blood volume withdrawn.

After the study, animals were killed using heavy sedation with IV pentobarbital. A dorsal laminectomy was performed, and the correct location of the epidural catheter was confirmed by direct vision. The organs (brain, heart, kidneys, and the L6-7 segment of the spinal cord) were dissected and cut into samples weighing 150–300 mg each. Colored microspheres were assayed by using high-pressure liquid chromatography (6).

Exclusion criteria included incorrect location of the epidural catheter, as determined at autopsy, and inadequate sphere injection or mixing in blood, as assessed by comparing left and right renal blood flow.

Cardiac output (CO) was determined by: CO = Qref x NSinj/NSblood where Qref = rate of reference blood sampling (mL/min) and NSinj and NSblood = number of spheres injected and number of spheres measured in the blood, respectively. CO is expressed in mL · min-1 · kg-1. Regional blood flow values were determined by: Qorg = NSorg x Qref/NSblood where NSorg = number of spheres measured in each organ sample. Qorg is expressed in mL · min-1 · g-1.

We compared the two groups (adult and young rabbits) for basal values using nested two-way analysis of variance (ANOVA); thereafter, the two groups were analyzed separately. Whatever the result of this first comparison, demographic data and basal values were compared within each group using one-way ANOVA. Hemodynamic and flow values were compared among subgroups and time points by using two-way ANOVA for repeated measures, followed by a Neuman-Keuls test when appropriate. We tested the correlation between change in SCBF (flow at time Tn + 1 - flow at time Tn) over changes in mean arterial pressure (MAP) (MAP at time Tn + 1 - MAP at time Tn) using linear regression. ANOVA was used to test the within-group (adult and young rabbits) significance of the linear regression (8). Data are expressed as mean ± SEM unless otherwise specified.


   Results
Top
 Abstract
 Introduction
 Methods
 Results
Discussion
 References
 
We studied 22 adult rabbits weighing 2240 ± 356 g (mean ± SD) and 27 young rabbits weighing 396 ± 61 g. Adult and young rabbits were assigned to the following subgroups: saline (n = 7 and 9), plain lidocaine (n = 8 and 8), and lidocaine with epinephrine (n = 7 and 10), respectively. The upper level of segmental anesthesia was around T8 (lack of tachycardia after pinprick test) and was not different among lidocaine subgroups.

Adult Rabbits
Baseline values of MAP were not different among subgroups (saline 79 ± 6, plain lidocaine 78 ± 3, lidocaine with epinephrine 71 ± 2 mm Hg). MAP significantly decreased after the epidural administration of lidocaine with and without epinephrine (Fig. 1).



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  		Figure 1. Mean arterial pressure (MAP) in adult rabbits (a) and in young rabbits (b) before epidural injection (T0) and 7.5 (T1), 30 (T2) and 40 min (T3) after epidural injection. • = saline, {square} = plain lidocaine, {diamondsuit} = lidocaine with epinephrine 1:200,000. *P < 0.05 versus all other time points within the subgroup. §P < 0.05 versus T0 and T3.

 
Baseline CO and organ blood flows were not different among subgroups. CO significantly decreased with time, but no difference was found among subgroups (Table 1). No variation in cerebral, coronary, and kidney blood flows was noted. SCBF in the lumbar segments did not change after the administration of epidural lidocaine with or without epinephrine. No correlation was found between changes in MAP and changes in SCBF in these adult rabbits.


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  		Table 1. Cardiac Output (CO) and Organ Blood Flow in Adult Rabbits
 
Young Rabbits
Baseline values of MAP were significantly lower than those of adult rabbits, but no difference was found among subgroups (saline 57 ± 3, plain lidocaine 60 ± 3, lidocaine with epinephrine 55 ± 3 mm Hg). MAP significantly decreased in both lidocaine subgroups (Fig. 1). This decrease in MAP was less pronounced in young rabbits compared with adult rabbits; however, as with older rabbits, the addition of epinephrine had no effect on the observed reduction in MAP.

No difference in CO and regional flows were detected among subgroups at baseline, before any epidural injection (Table 2). However, baseline CO, SCBF, and coronary blood flows were significantly higher in young versus older rabbits, whereas baseline renal and cerebral blood flows were similar to those measured in adult rabbits. CO significantly decreased with time in young rabbits. No variation in coronary and kidney blood flows was noticed. Contrary to what was observed in adult rabbits, SCBF significantly decreased with time. A slight but significant increase in cerebral blood flow with time was also found in young rabbits. No difference among subgroups was found in either SCBF or cerebral blood flow in young rabbits. In contrast to adult rabbits, a significant positive correlation was found between changes in MAP and changes in SCBF after the administration of plain lidocaine ({Delta}flow = 0.016 x {Delta}MAP - 0.11; r2 = 0.37) and after the administration of lidocaine with epinephrine ({Delta}flow = 0.009 x {Delta}MAP + 0.02; r2 = 0.45). No departure from parallelism was detected between these two subgroups.


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  		Table 2. Cardiac Output (CO) and Organ Blood Flow in Young Rabbits
 
Six additional adult rabbits weighing 2210 ± 125 g and five young rabbits weighing 420 ± 50 g receiving epinephrine (5 µg/mL) alone via the epidural route were studied. No differences in SCBF were detected with time in either adult or young rabbits. CO significantly increased with time in adult rabbits, whereas it remained unchanged in young rabbits (Tables 1 and 2). MAP remained stable throughout the study in adult rabbits (73 ± 9, 75 ± 9, and 73 ± 7 mm Hg at T0, T1, and T2, respectively), whereas MAP significantly increased with time in young rabbits (53 ± 4, 54 ± 10, and 59 ± 9 mm Hg at T0, T1, and T2 respectively).

With or without epinephrine, lidocaine plasma concentrations were significantly lower in young rabbits (1.28 ± 0.54 or 1.60 ± 0.44 µg/mL, respectively) than those in adult rabbits (3.00 ± 1.67 or 4.07 ± 1.73 µg/mL, respectively) (mean ± SD).


   Discussion
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
References
 
We compared the effect of plain lidocaine and lidocaine with epinephrine on regional blood flows in young and adult rabbits. We focused on SCBF because epinephrine might have deleterious effects on SCBF in infants (3). The animals studied (3 wk old, weaned for 0–3 days) were not exactly "infant" but rather between "infant" and "child" rabbits. However, a major difference in the sensitivity of the vagus nerve to local anesthetics has been demonstrated in 1-mo-old rabbits compared with 9-mo-old rabbits (9), which indicates that neurologic maturation is still incomplete in rabbits 4 wk old. The time period studied was derived from a previous experiment performed on awake adult rabbits, which showed that the maximal decrease in MAP was observed 7–10 min after an epidural injection of 1 mL of plain 2% lidocaine, and MAP had returned to baseline values within 30 min (5).

In adult rabbits, the epidural administration of lidocaine, with or without epinephrine, induced a significant reduction in MAP (Fig. 1) with a magnitude and time course in accordance with a previous study using the same animal model (5). Despite this finding, regional blood flows did not significantly change in adult rabbits over time. No correlation was found between changes in MAP and changes in SCBF.

There are conflicting data concerning the SCBF responses to subarachnoid or extradural injection of local anesthetics with or without epinephrine. Indeed, no change in SCBF was detected after the subarachnoid administration of lidocaine, with or without epinephrine, in anesthetized cats (10) or dogs1; after the subarachnoid administration of tetracaine, with or without epinephrine, in dogs2; or after the subarachnoid administration of lidocaine, mepivacaine, and tetracaine, with or without epinephrine, in cats.3 Surprisingly, an increase in SCBF has been shown after the subarachnoid administration of plain lidocaine (but not lidocaine with epinephrine) in the dog (11). Conversely, a significant decrease in SCBF after the subarachnoid administration of bupivacaine has been reported in rats (12) and in dogs (13). Similarly, Dohi et al. (14) showed that subarachnoid lidocaine with phenylephrine, but not plain lidocaine, diminished SCBF in dogs. When injected epidurally, lidocaine has been shown to decrease SCBF in the dog (15). Malinovsky et al. (16) showed that both epidural plain 0.5% bupivacaine and epidural bupivacaine-loaded microspheres decreased SCBF in awake rabbits. Several factors may explain these discrepancies: 1) the placement of the epidural catheter using a surgical or a percutaneous technique leading to varying degrees of noxious stimulation; 2) the association of general anesthesia in some studies; 3) the method used to measure regional blood flows; 4) different drugs, such as bupivacaine, lidocaine, mepivacaine, or tetracaine; and 5) the site of injection (subarachnoid versus epidural). Moreover, the addition of vasoactive drugs (epinephrine, phenylephrine, etc.) may have additional local and/or systemic effects. In fact, it is well known that the spinal cord has a limited blood supply and is vulnerable to ischemia (17). In our study, adult rabbit MAP was maintained between 50 and 150 mm Hg, which is the range of pressure in which, via autoregulation, the blood flow of preserved organs (brain, kidney, heart, spinal cord) remains unchanged (17,18). This may explain the absence of variation in the SCBF in our adult rabbit group despite a significant reduction in MAP (18,19).

In young rabbits, the decrease in MAP observed after epidural lidocaine administration was much less than that in adult rabbits. In pediatric patients, epidural anesthesia produces little to no change in blood pressure (20,21). We used lidocaine 2% (which is rarely used in pediatric practice) to increase the incidence of adverse effects. The resulting block induced a significant decrease in MAP in the two subgroups receiving lidocaine, but this decrease was only significant 7.5 min after lidocaine injection in the plain lidocaine group, compared with 7.5 and 30 min after injection in the lidocaine with epinephrine group (Fig. 1). At these specific times, the average MAP was <50 mm Hg in these two subgroups. Contrary to what was observed in adult rabbits, a significant reduction in SCBF was then noticed. However, in the two subgroups of young rabbits receiving lidocaine, changes in SCBF were correlated to changes in MAP with 37% and 45% of the variation in flow explained by the variation in MAP in the plain lidocaine subgroup and in the lidocaine with epinephrine subgroup, respectively. This is likely related to the fact that, because of the lower values of MAP at baseline, a decrease in MAP <50 mm Hg is more frequent in young rabbits than in adults and is rapidly followed by a loss of autoregulation (17–19). However, young rabbits had a significantly higher basal SCBF than adults, and the mean SCBF after lidocaine injection was greater than the corresponding flow in adults. SCBF then decreased in young rabbits, and this decrease was parallel to the decrease in MAP.

In additional groups of rabbits receiving epinephrine alone, SCBF did not change throughout the study in adult or young animals. The increase in CO with time observed in adult rabbits and the increase in MAP observed in young rabbits may be related to a lightning of anesthesia. However, SCBF remains stable even when expressed as a fraction of CO. Thus, the hypotension observed in the group receiving 2% lidocaine epidurally in combination with general anesthesia seems to be the main factor that led to decreased SCBF in young rabbits.

Changes in SCBF usually parallel changes in cerebral blood flow (22). It is therefore not surprising that cerebral blood flow remains stable in adult rabbits, as was observed for SCBF. Surprisingly, cerebral blood flow increased in young rabbits. It is known that cerebral blood flow is preserved in infants during caudal anesthesia (23). Using a Doppler technique in 6-mo-old infants, Payen et al. (23) showed that caudal anesthesia with bupivacaine 3.25 mg/kg performed during light general anesthesia did not decrease cerebral blood flow, although a marked reduction in brachial blood flow was observed (23). We observed a paradoxical increase in cerebral blood flow in young rabbits, which might be attributed to lightning of general anesthesia during the course of the experiment.

Although this study can be criticized because it is not general practice to maintain general anesthesia with pentobarbital in pediatric anesthesia, the same technique of anesthesia has been used for all of our groups of rabbits.

In conclusion, lidocaine 2% with or without 1:200,000 epinephrine induced a decrease in SCBF in young, but not in adult, rabbits. This reduction of SCBF correlated to a decrease in MAP likely due to the association of epidural and general anesthesia. SCBF did not decrease with blood pressure in the corresponding adult rabbit groups. However, because of a higher basal blood pressure, adult rabbits maintained their MAP >50 mm Hg, which is considered the critical value of autoregulation (17–19). The decrease in SCBF observed in young rabbits did not correlate to the use of epinephrine. This negative result may be due to a lack of power of the experiment; in any case, epinephrine did not seem to be the primary cause of decreased SCBF in young rabbits. Finally, although our results cannot be directly applied to humans, and although hypotension is rare in infants and children receiving epidural anesthesia (20,21,23), this study suggests that, when combined with general anesthesia, a reduction in blood pressure might reduce SCBF. Not only should blood pressure be carefully monitored, but events that might cause a reduction in blood pressure should be avoided, and any reduction in blood pressure should be immediately and effectively treated.


   Acknowledgments
 
Supported in part by a grant from Association MAPAR.

We thank Mrs. Régine Le Guen for her expert technical assistance on the high-performance liquid chromatography measurement of colored microspheres.


   Footnotes
 
1 De Rosayro AM, Tait AR, LaBond V, et al. The effect of subarachnoid lidocaine and epinephrine on spinal cord bloodflow [abstract]. Anesthesiology 1983;59:208. Back

2 Kozody R, Cumming M, Palahniuk RJ. Spinal cord bloodflow following subarachnoid block with and without epinephrine [abstract]. Anesth Analg 1984;63:238. Back

3 Smith SL, Albin MS, Watson WA, et al. Spinal cord and cerebral bloodflow responses to intrathecal local anesthetics with and without epinephrine [abstract]. Anesthesiology 1993;59:312. Back


   References
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 

  1. Auroy Y, Narchi P, Messiah A, et al. Serious complications related to regional anesthesia: results of a prospective study in France. Anesthesiology 1997;87:479–86.[Web of Science][Medline]
  2. Giaufré E, Dalens B, Gombert A. Epidemiology and morbidity of regional anesthesia in children: a one-year prospective survey of the French-Language Society of Pediatric Anesthesiologists. Anesth Analg 1996;83:904–12.[Abstract]
  3. Flandin-Blétry C, Barrier G. Accidents following extradural analgesia in children: the results of a retrospective study. Paediatr Anaesth 1995;5:41–6.[Web of Science][Medline]
  4. Warner MA, Kunkel SE, Offord KO, et al. The effects of age, epinephrine and operative site on duration of caudal anesthesia in pediatric patients. Anesth Analg 1987;66:995–8.[Abstract/Free Full Text]
  5. Malinovsky JM, Bernard JM, Baudrimont M, et al. A chronic model for experimental investigation of epidural anesthesia in the rabbit. Reg Anesth 1997;22:80–5.[Web of Science][Medline]
  6. Mazoit JX, Le Guen R, Decaux A, et al. Application of HPLC to counting of colored microspheres in determination of regional blood flow. Am J Physiol 1998;274:H1041–7.[Abstract/Free Full Text]
  7. Bassingthwaighte JB, Malon MA, Moffett TC, et al. Validity of microsphere depositions for regional myocardial flows. Am J Physiol 1987;253:H184–93.[Abstract/Free Full Text]
  8. Armitage P, Berry G. Statistical methods in medical research. Oxford:Blackwell, 1994:292–311.
  9. Benzon HT, Strichartz GR, Gissen AJ, et al. Developmental neurophysiology of mammalian peripheral nerves and age-related differential sensitivity to local anaesthetic. Br J Anaesth 1988;61:754–60.[Abstract/Free Full Text]
  10. Porter SS, Albin MS, Watson WA, et al. Spinal cord and cerebral blood flow responses to subarachnoid injection of local anesthetics with and without epinephrine. Acta Anaesthesiol Scand 1985;29:330–8.[Web of Science][Medline]
  11. Kozody R, Swartz J, Palahniuk RJ, et al. Spinal cord blood flow following sub-arachnoid lidocaine. Can Anaesth Soc J 1985;32:472–8.[Web of Science][Medline]
  12. Crosby G. Local spinal cord blood flow and glucose utilization during spinal anesthesia with bupivacaine in conscious rats. Anesthesiology 1985;63:55–60.[Web of Science][Medline]
  13. Kozody R, Ong B, Palahniuk RJ, et al. Subarachnoid bupivacaine decreases spinal cord blood flow in dogs. Can Anaesth Soc J 1985;32:216–22.[Web of Science][Medline]
  14. Dohi S, Matsumiya N, Takeshima R, Naito H. The effects of subarachnoid lidocaine and phenylephrine on spinal cord and cerebral blood flow in dogs. Anesthesiology 1984;61:238–44.[Web of Science][Medline]
  15. Mitchell P, Goad R, Erwin CW, et al. Effect of epidural lidocaine on spinal cord blood flow. Anesth Analg 1989;68:312–7.[Abstract/Free Full Text]
  16. Malinovsky JM, Bernard JM, Le Corre P, et al. Extradural bupivacaine-loaded microspheres and spinal cord blood flow in the chronically instrumented rabbit. Clin Physiol 1997;17:361–70.[Medline]
  17. Marcus ML, Heistad DD, Ehrhardt JC, Abboud FM. Regulation of total and regional spinal cord blood flow. Circ Res 1977;41:128–34.[Free Full Text]
  18. Kobrine AI, Doyle TF, Rizoli HV. Spinal cord blood flow as affected by changes in systemic arterial blood pressure. J Neurosurg 1976;44:12–5.[Web of Science][Medline]
  19. Kobrine AI, Doyle TF, Martin AN. Autoregulation of spinal cord blood flow. Clin Neurosurg 1975;22:573–81.[Medline]
  20. Ecoffey C, Dubousset AM, Samii K. Lumbar and thoracic epidural anesthesia for urologic and upper abdominal surgery in infants and children. Anesthesiology 1986;65:87–90.[Web of Science][Medline]
  21. Dalens BJ, Mazoit JX. Adverse effects of regional anaesthesia in children: incidence, management and prevention. Drug Safety 1998;19:251–68.[Web of Science][Medline]
  22. Hickey R, Albin MS, Bunegin L, Gelineau J. Autoregulation of spinal cord blood flow: is the cord a microcosm of the brain? Stroke 1986;17:1183–9.[Abstract/Free Full Text]
  23. Payen D, Ecoffey C, Carli P, Dubousset AM. Pulsed Doppler ascending aortic, carotid, brachial, and femoral artery blood flows during caudal anesthesia in infants. Anesthesiology 1987;67:681–5.[Web of Science][Medline]
Accepted for publication March 9, 1999.





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Lippincott, Williams & Wilkins Anesthesia & Analgesia® is published for the International Anesthesia Research Society® by Lippincott Williams & Wilkins and Stanford University Libraries' HighWire Press®. Copyright 1999 by the International Anesthesia Research Society. Online ISSN: 1526-7598   Print ISSN: 0003-2999 HighWire Press