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Anesth Analg 2004;99:1038-1043
© 2004 International Anesthesia Research Society
doi: 10.1213/01.ANE.0000132547.39180.88


PEDIATRIC ANESTHESIA

William J. Greeley Section Editor

Peripherally Inserted Central Catheters: A Randomized, Controlled, Prospective Trial in Pediatric Surgical Patients

Deborah A. Schwengel, MD*, John McGready, MS{dagger}, Sean M. Berenholtz, MD MHS*, Lori J. Kozlowski, RN MS, CPNP*, David G. Nichols, MD MBA*, and Myron Yaster, MD*

*Departments of Anesthesiology and Critical Care Medicine, Surgery, and Pediatrics, The Johns Hopkins University School of Medicine; and {dagger}Department of Biostatistics, The Johns Hopkins University School of Public Health, Baltimore, Maryland

Address correspondence and reprint requests to Deborah A. Schwengel, MD, Blalock 904, The Johns Hopkins Hospital, 600 N. Wolfe St., Baltimore, MD 21287. Address e-mail to dschweng{at}jhmi.edu


    Abstract
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
Peripherally-inserted central catheters (PICCs) are long-term IV catheters used for drug and fluid administration, blood sampling, or hyperalimentation. The short-term use of PICCs in postoperative patients has not been studied. In this randomized, controlled trial, patients received either a PICC or peripheral IV catheter (PIV). Our outcome measures were patient and parent satisfaction with care, complications of the venous access devices, number of postoperative venipunctures, and cost-effectiveness of use. Satisfaction was significantly more frequent in the PICC group (P < 0.05), and there were significantly fewer postoperative needle punctures in the PICC group compared with the PIV group (P < 0.05). Minor complications were common in the PIV group; major complications were uncommon in both groups. PICCs are more expensive, but better satisfaction can make them a cost-effective option. Additionally, insertion during surgical preparation time in the operating room (OR) means that cost is not increased by adding anesthesiologist and OR time. Anesthesiologists should consider placing PICCs in patients requiring more than 4 days of in-hospital postoperative care, especially if frequent blood sampling or IV access is required.

IMPLICATIONS: In this randomized, controlled trial, we found that peripherally inserted central catheters safely and effectively reduce needle punctures and improve patient satisfaction. The technique is cost-effective if anesthesiologists insert the catheters during surgical preparation time.


    Introduction
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
Long-term indwelling central catheters prevent the pain of repeated venipuncture. Since the 1970s, peripherally inserted central catheters (PICCs) have been used in neonates who require long-term IV access. These central catheters have frequent insertion success and a small risk of catheter-related complications (1–7). They are now often used in pediatric and adult patients who require home IV therapy (8) or long-term IV access for drug and fluid administration, blood sampling, or hyperalimentation (9,10). PICCs are often inserted only after multiple venipunctures have been attempted or when peripheral IV (PIV) insertion sites have been exhausted; PICC insertion may then require deep sedation or general anesthesia.

We hypothesized that preemptive placement of PICCs during elective surgery would decrease or eliminate painful venipunctures and improve patient (parental) satisfaction when used for 4–7 days. Additionally, we hypothesized that patients with PICCs would have fewer catheter-related complications than patients with PIVs and that this technology would be cost-effective even with short-term use.


    Methods
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
Pediatric patients from neonates to 14-yr-olds were prospectively enrolled if they were scheduled for an anticipated postoperative hospital stay of at least 4 days. Patients were excluded if their parents or guardians could not speak English, were otherwise unable to provide consent, or were unable to complete the satisfaction survey. We also excluded patients who required central venous access during their hospital stay and patients who were enrolled in a conflicting investigational trial. Patients or their parents could request withdrawal from the study at any time during their hospital stay.

After approval of the institution’s IRB and receipt of informed parental consent and, when applicable, patient assent, patients were randomized by using a sealed, opaque envelope to receive either PICC or PIV. Randomization was performed before the induction of anesthesia for the proposed surgical procedure. There was no patient stratification within groups. Anesthetic management was not standardized, but after the induction of general anesthesia, all patients had a PIV inserted. Patients randomized to the PICC group had a PICC (Cook Incorporated, Bloomington, IN) inserted by an attending anesthesiologist (Fig. 1). Veins for cannulation were identified by palpation or visualization. An ultrasound technique was not used. In the PICC group, the PIV placed after the induction of anesthesia was either converted to a heparin lock and not used or was removed.


Figure 1
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Figure 1. Peripherally-inserted central catheter (PICC) placement procedure. Step 1: after cleansing and draping the skin, cannulate the vein with a 22-gauge IV catheter. Remove the catheter needle, insert a straight (Seldinger) wire into the vein, and remove the tourniquet and IV catheter. Step 2: incise the skin and subcutaneous tissue with a scalpel. Dilate the path from skin to vein with a 5.5F dilator, and then remove the dilator, leaving the wire in the vein. Step 3: place the peel-away introducer and 4.5F dilator unit over the wire, and thread it into the vein. Step 4: remove the wire and 4.5F dilator, leaving the peel-away introducer in the vein. Advance the measured and cut PICC through the peel-away introducer. Peel away the introducer, and affix the silicone catheter to the skin.

 
We collected patient demographic data, including age, weight, surgical procedure, and number of previous hospitalizations. We documented the time required to insert the study catheter, the site of insertion, and PICC length. Placement was considered a failure if providers were unable to place the catheter after attempts at three insertion sites.

Postoperative fluid management and laboratory studies were dictated by the patient care team. Bedside nurses kept a running log of problems with catheter care and the number of needle punctures a patient received. A study nurse collected data on complications associated with IV therapy, including catheter occlusion and malfunction, broken catheters, catheter dislocation, IV infiltration, bacteremia, fever, fluid leakage or blood at the insertion site, phlebitis, and missed or delayed fluid or drug administration. Parents and the patient (if old enough) were given a satisfaction survey to complete at the time of PICC removal, at discharge, or at 7 days.

For statistical analysis, Stata Version 7.0 (Stata Corp., College Station, TX) and Prism Version 3.0 (GraphPad Software, San Diego, CA) were used. Exploratory data analysis was conducted on all data collected and presented in appropriate graphical displays and tables. Statistical significance was defined as P < 0.05.

The sample size estimate was based on our satisfaction hypothesis. At the inception of the study, we had estimated a sample size of 97 patients in each group, assuming a 40% excellent satisfaction score in the PIV group versus a 60% excellent satisfaction score in the PICC group ({alpha} error = 0.05; and ß error = 0.8). We planned an interim analysis based on O’Brien and Fleming’s stopping boundary (11).

Our primary hypothesis was that patient/parent satisfaction levels would differ between the PIV and the PICC groups. We compared the proportion of patients in each group who reported the highest level of satisfaction on each of the eight questions of the patient satisfaction survey. We calculated the difference in proportions between groups and the 95% confidence intervals (95% CI). Statistical significance was assessed with Fisher’s exact tests.

Patients randomized to PICC who had failed PICC placement were analyzed in the PIV group rather than in an intention-to-treat group. A sensitivity analysis was performed to determine whether our results would change when the failed PICC patients were removed from analysis. Ninety-five percent CIs for group differences in responses to each of the eight satisfaction items were recomputed without including data on the failed PICC patients in the PIV groups; P values were also recomputed. The results of both analyses (with and without failed PICC patients) were compared to see whether the substantive interpretation and statistical results differed.

We also compared the complications in the two groups. Objective measures of patient complications, such as the mean number of insertion attempts on the first study device, and other continuous measures were compared via a two-sample Student’s t-test, and 95% CIs were computed for mean differences between the PIV and PICC groups.

We evaluated the potential effect of PICC placement on economic outcomes. We calculated the provider costs for each patient by collecting the labor (anesthesiologist and phlebotomist time), equipment (PICC trays and IV catheters), and operating room (OR) time costs. Anesthesiologist cost was calculated per unit of time on the basis of average salary and benefits at our institution. Phlebotomist cost was estimated on the basis of average salary plus benefits at our institution divided by the average time required for each venipuncture. We measured the number of minutes required to place the initial study catheter in the OR. To establish an average cost for either IV starts or phlebotomy, we had previously recorded time spent by pediatric phlebotomists for 358 patient encounters. On the basis of these data, the average amount of time per encounter was calculated for IV starts and phlebotomy. Therefore, PICC and PIV costs were calculated according to the following formula:


Formula 1

To evaluate, we calculated the satisfaction score based on the results of the satisfaction survey. An aggregate satisfaction score was obtained based on the scaled Likert score. Each question was given a possible maximum value of 1 and a minimum value of 0. The maximum possible score for each patient was 8, and the lowest possible score was 0. Each of the five possible responses on the Likert scale was weighted as follows: highest satisfaction = 1, some satisfaction = 0.75, neither satisfied nor dissatisfied = 0.5, some dissatisfaction = 0.25, very dissatisfied = 0. The scores were totaled for each patient. The cost-effectiveness was calculated as total costs/satisfaction score.


    Results
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
Ninety-six infants and children who underwent genitourinary (n = 37), general pediatric surgical (n = 25), neurosurgical (n = 23), and other (n = 7) procedures were enrolled in the study. A statistically significant difference was detected, and the study was therefore halted. Forty-nine patients were randomized to the PIV group and 47 to the PICC group. Ninety-two patients were included in the analysis; the four excluded patients were discharged early. Eight patients in the PICC group had failed PICC placements and were analyzed in their treatment group. Six patients did not return satisfaction surveys and were not included in the satisfaction analysis but were included in the complication analysis.

There were no significant differences between groups in terms of patient age, sex, weight, or number of previous hospitalizations. All patients received routine maintenance and third-space IV fluid replacement, as well as surgical and patient-specific IV antibiotic prophylaxis.

We scored all of the patient surveys that responded with highest satisfaction to each of the eight questions of the survey. The results were all statistically significant except for Question 5 (Table 1). The aggregate score for all questions was also significantly higher among patients in the PICC group (mean, 6.76; SD, 1.57) compared with the PIV group (mean, 4.95; SD, 1.84) (P < 0.0001).


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Table 1. Patient Satisfaction Data—Patients (%) Reporting the Highest Satisfaction with IV Care
 
The failed PICC patients’ scores were analyzed in the PIV group rather than an intention-to-treat group. We learned from the sensitivity analysis that all P values remained <0.05, and Question 5 was again not significantly different between groups.

We observed a significantly different number of needle punctures between groups. The number of postoperative IV restarts (SD) was 0.27 (1.07) in the PICC group and 1.5 (2.68) in the PIV group. The number of venipunctures was 0.3 (1.0) in the PICC group and 1.4 (1.9) in the PIV group.

Major complications were not different between groups. There were two study patients with positive blood cultures, one in each group, and neither was clearly due to the IV catheter. There were no complications such as broken or occluded PICCs, and there were no differences in maximum daily temperatures between groups. The two most common complications of the PICC were old blood at the site (56%) and failed placement (17%). One (2%) catheter fell out prematurely, and 36 (92%) functioned well during the study period. Other relatively minor complications were more common in the PIV group (Table 2).


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Table 2. Complications
 
More expensive equipment and time costs resulted in a higher overall cost of the PICC. The median insertion time (interquartile range) for PICC and PIV was, respectively, 19 min (15–25 min) and 5 min (3–12 min). The satisfaction in the PICC group was significantly higher, however; therefore, PICCs could be kept cost-effective if the insertion time in the OR was combined with surgical time. If PICCs were placed before the start of surgery, thus increasing use of the OR and anesthesiologist time, costs were higher, and cost-effectiveness was negated (Table 3).


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Table 3. Cost-Effectiveness (Total Cost/Satisfaction)
 

    Discussion
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 
This study demonstrates the safety and effectiveness of preemptive placement of PICCs in infants and children with anticipated postoperative hospital stays of four to seven days. Children with PICCs experienced fewer venipunctures for blood sampling and for replacement of failed IV catheters than children who had only PIV catheters placed at the time of surgery. Furthermore, fewer venipunctures resulted in less pain and increased patient and parental satisfaction with care. Finally, four to seven days’ use of PICCs resulted in fewer complications than PIV catheters and was cost-effective if the catheters were placed when surgery or surgical preparation was under way.

Hospitalization and the anticipation of painful medical procedures and needles ("shots") are terrifying experiences for many children (12,13). PIV catheters inserted at the time of surgery cannot be expected to last the duration of a patient’s postoperative hospital course, nor can they reliably be used to sample blood. Consequently, venipuncture becomes a necessary, albeit unfortunate, consequence of hospitalization and illness. However, it does not have to be painful. Topical local anesthetics such as EMLA® cream can minimize venipuncture pain, but these topical drugs do not eliminate pain or prevent dread of the procedure (14).

PICCs eliminate the need for multiple venipunctures. These catheters have become commonplace and have revolutionized the care of chronically ill children and children in whom IV access is difficult or impossible. Janes et al. (15) concluded that PICCs used in very-low-birth-weight infants significantly reduced IV insertions and needle punctures without adding morbidity in that patient population. Our study extends this technology to postoperative patients in whom the duration of use would be expected to last four to seven days.

Regardless of where and how they are placed, serious complications such as pneumothorax, thrombosis, infection, and catheter fracture have been associated with the use of central catheters. PICCs are less likely to incur major complications compared with central catheters placed in the subclavian or internal jugular veins. However, minor complications are common (16,17). Long-duration (up to 77 days) series reports from neonatal intensive care units describe complications as infectious (bacteremia/sepsis) or mechanical (2–7). Mechanical complications, such as catheter occlusion, fluid extravasation, dislodgment, or thrombosis, were the reason for removal of the lines in 10%–43% of the cases (2,4–6). Complications in older patients are infrequent (8–10), but there are isolated case reports of difficulty removing catheters and broken catheters (18,19). There are no reports of short-term PICC use, but complication rates reported in one case series increased once catheters were in place for ≥20 days (20). Others have reported that central placement results in less phlebitis, occlusion, and leaking than noncentral tip locations (21).

We did not see more frequent complications in the PICC group in this study. In fact, there was more local injury in the PIV group (phlebitis and infiltrates). One concern about the use of PICCs is the possibility of thrombotic complications. We did not have any clotted catheters or symptomatic thrombotic events; we did not evaluate the presence of asymptomatic thromboses, nor do we know the significance of asymptomatic thromboses. Screening for asymptomatic thromboses should be the topic of future studies.

The cost of PICC is higher than PIV, both in terms of labor and equipment. Our lowest total cost of $173.58 was 1.59 times the cost of PIV care ($108.49). The highest cost increased to $440.70 (4 times the cost of the PIV). However, the total cost in relation to a hospital stay is a small fraction of the total. Patients may ultimately have no awareness of the individual monetary cost of the PICC, but they will be very aware of their level of satisfaction and memory of the number of needle punctures, number of times awakened from sleep, and other unpleasant hospital events. Parents also commented on the survey that the PICC was more comfortable, with no arm board and better limb mobility. Patients might score the value of the PICC differently than the provider. The increased costs of PICCs might be viewed negatively by administrators. Satisfaction scores can be used as a way to evaluate the value of treatment to the patient. Longer hospitalizations make the PICC more cost-effective, and if PIV placement becomes impossible, PICC or central line placement becomes necessary and might require an additional anesthetic.

Each physician and each institution will have to decide whether their costs of PICC placement will be more or less than those we have reported. To achieve the cost of $173.58, we placed PICCs at the same time that the patient was being prepared for the procedure or when the procedure was under way. If OR time is used exclusively for PICC placement, then costs for OR time and the anesthesiologist’s time should be included in the analysis. We also placed our catheters in the midclavicular position unless the catheter would be used for parenteral nutrition or medications requiring central location; consequently, chest radiographs were not routinely performed. In absolute dollars, the cost might still be very positive for the patient and the provider because of the improvements in patient satisfaction that result from the reduction of painful events. Each institution must determine whether their costs warrant placement.

Finally, insertion failure was more frequent than previously reported. We do not believe that this was due to inexperience, the size of the catheters (3F or 4F), or operator inexperience. Rather, in many of the children studied, the basilic, cephalic, and greater saphenous veins could not be readily seen or palpated. Perhaps, in retrospect, this technique should not have been attempted in these patients. Alternatively, we could use techniques and technologies that could increase our ability to access peripheral veins, such as ultrasound imaging or transillumination. Ultrasound imaging uses relatively inexpensive technology to image veins and arteries in real time. It is commonly used with great success in the catheterization laboratories and in some ORs and deserves future study.

The satisfaction survey that we used is not a validated tool, but the results were highly clinically and statistically significant when analyzed in two different ways. Objective results, including the number of IV restarts and the number of venipunctures for blood sampling, were significantly more frequent in the control group. Because the control group also had lower satisfaction scores, we conclude that the objective and subjective data corroborate each other. Because this was a nonblinded study, we cannot eliminate the possibility of attitude bias introduced by staff members caring for the patients. To minimize bias in completing the survey, parents were given the survey to complete in private for return to a nurse in a sealed envelope.

Anesthesiologists, surgeons, or other physicians should consider placing PICCs in patients who require more than four days of in-hospital postoperative care, especially if frequent blood sampling or IV access is anticipated or required.


    Acknowledgments
 
PICC catheters were provided free of charge by Cook Critical Care, a division of Cook Incorporated, Bloomington, IN. SMB was supported in part by Grant K23HL70058-01 from the National Heart, Lung and Blood Institute.

The authors wish to acknowledge the faculty, fellows, and pediatric pain nurse practitioners of the Department of Anesthesiology and Critical Care Medicine of the Johns Hopkins University School of Medicine. Additionally, the authors wish to acknowledge the support of the faculty of the Divisions of Pediatric General Surgery, Pediatric Neurosurgery, Pediatric Orthopedics, and Pediatric Urology of the Johns Hopkins University School of Medicine and the nurses of the Children’s Center of the Johns Hopkins Hospital.


    Footnotes
 
Cook Critical Care had no role in the design or analysis of this study, interpretation of data, or preparation or review of the manuscript.


    References
 Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 References
 

  1. Dolcourt J, Bose C. Percutaneous insertion of silastic central venous catheters in newborn infants. Pediatrics 1982; 70: 484–6.[Abstract/Free Full Text]
  2. Durand M, Ramanathan R, Martinelli B, Tolentino M. Prospective evaluation of percutaneous central venous silastic catheters in newborn infants with birth weights of 510 to 3920 grams. Pediatrics 1986; 78: 245–50.[Abstract/Free Full Text]
  3. Rudin C, Nars PW. A comparative study of two different percutaneous venous catheters in newborn infants. Eur J Pediatr 1990; 150: 119–24.[ISI][Medline]
  4. Chathas MK, Paton JB, Fisher DE. Percutaneous central venous catheterization. Am J Dis Child 1990; 144: 1246–50.[Abstract]
  5. Soong WJ, Hwang B. Percutaneous central venous catheterization: five year experiment in a neonatal intensive care unit. Acta Paediatr Sin 1993; 34: 356–66.
  6. Klein J, Shahrivar F. Use of percutaneous silastic central venous catheters in neonates and the management of infectious complications. Am J Perinatol 1992; 9: 261–4.[ISI][Medline]
  7. Cairns PA, Wilson DC, McClure BG, et al. Percutaneous central venous catheter use in the very low birth weight neonate. Eur J Pediatr 1995; 154: 145–7.[ISI][Medline]
  8. Weeks-Lozano H. Clinical evaluation of Per Q Cath for both pediatric and adult home infusion therapy. J Intraven Nurs 1991; 14: 249–56.[Medline]
  9. Pauley SY, Vallande NC, Riley EN, et al. Catheter-related colonization associated with percutaneous inserted central catheters. J Intrav Nurs 1993; 16: 50–4.[Medline]
  10. Shepherd R, Ong TH. Evaluation of percutaneously inserted peripheral silicone catheters for parenteral nutrition in infants and children. Aust Paediatr J 1980; 16: 181–4.[ISI][Medline]
  11. O’Brien PC, Fleming TR. A multiple testing procedure for clinical trials. Biometrics 1979; 35: 549–56.[ISI][Medline]
  12. Humphrey GB, Boon CJ, van den Heuvell GC. The occurrence of high levels of acute behavioral distress in children and adolescents undergoing routine venipunctures. Pediatrics 1992; 90: 87–91.[Abstract/Free Full Text]
  13. Rice LJ. Needle phobia: an anesthesiologist’s perspective. J Pediatr 1993; 122: S9–S13.[ISI][Medline]
  14. Soliman IE, Broadman LM, Hannallah RS, McGill WA. Comparison of the analgesic effects of EMLA (eutectic mixture of local anesthetics) to intradermal lidocaine infiltration prior to venous cannulation in unpremedicated children. Anesthesiology 1988; 68: 804–6.[ISI][Medline]
  15. Janes M, Kalyn A, Paes B. A randomized trial comparing peripherally inserted central venous catheters and peripheral intravenous catheters in infants with very low birth weight. J Pediatr Surg 2000; 35: 1040–4.[ISI][Medline]
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  19. Uemura S, Fukuchi S, Tsuruta Y, et al. A case of percutaneous removal of a catheter fragment from the pulmonary artery using a long sheath. Kokyu To Junkan 1993; 41: 497–9.[Medline]
  20. Smith JR, Friedell ML, Cheatham ML, et al. Peripherally inserted central catheters revisited. Am J Surg 1998; 176: 208–11.[ISI][Medline]
  21. Racadio JM, Doellman DA, Johnson ND, et al. Pediatric peripherally inserted central catheters: complication rates related to catheter tip location. Pediatrics 2001; 107: E28.
Accepted for publication April 27, 2004.





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Lippincott, Williams & Wilkins Anesthesia & Analgesia® is published for the International Anesthesia Research Society® by Lippincott Williams & Wilkins with the assistance of Stanford University Libraries' HighWire Press®. Copyright 2006 by the International Anesthesia Research Society. Online ISSN: 1526-7598   Print ISSN: 0003-2999 HighWire Press