Abstract ID: A24

Abstract Title: Do continuous peripheral nerve catheters provide superior pain control to opioids? A meta-analysis

Poster Type: Poster

ABSTRACT BODY

Introduction: Numerous clinical trials have been published examining the efficacy of peripheral nerve catheters for the treatment of postoperative pain in both upper and lower extremity surgery in relation to opioids. Although the majority of randomized clinical trials conclude that continuous peripheral nerve catheters (PNC) decrease postoperative pain and opioid related side effects when compared to opioids, studies have been on relatively small numbers of patients and many failed to show statistical significance for reduced pain or side effects.
Methods: Studies were identified primarily by searching Ovid Medline (1966 to May 21, 2004) for terms related to postoperative analgesia with PNC and opioids. Inclusion criteria were a comparison of PNC versus opioids for postoperative analgesia, measurement of pain using a visual analog scale (VAS), randomization of patients and adult subjects. Each article from the final search was reviewed and data extracted from tables, text, or extrapolated from figures as needed. Weighted mean pain scores, weighted mean differences in pain score and weighted incidences of complications were determined using a fixed-effect model.
Results: A total of 19 articles met all inclusion criteria. Perineural analgesia provided better postoperative analgesia compared with opioids(P<0.001. This effect was seen for all time periods measured for both mean VAS and maximum VAS at 24 (P<0.001), 48 (P<0.001) and 72(Mean VAS only) (P<0.003) hours postoperatively. Perineural catheters provided superior analgesia to opioids (P≤0.007) for all catheter locations and time periods. Nausea/vomiting, sedation and pruritus all occurred more commonly with opioid analgesia (P<0.001).
Conclusions: We performed a meta-analysis of RCT's and found that when compared with opioid (parenteral or intravenous), perineural catheters with local anesthetic provided significantly enhanced analgesia for postoperative pain. Improvements in analgesia were noted through postoperative day 3. When analyzed according to catheter location, (e.g. interscalene, femoral, popliteal) and type of pain assessment (rest versus maximal pain), PNC's provided better postoperative analgesia than opioids. The use of PNC's also resulted in a lower incidence of certain minor complications including nausea/vomiting, pruritus and sedation and improved patient satisfaction. There are several limitations to this study including those that relate to the general use of a meta-analysis and others which pertain specifically to the issue examined (opioid vs. perineural catheter analgesia). The clinical significance of our findings with regards to a decrease in mean and maximal VAS may not correlate with the finding of a statistically significant decrease in pain with the use of perineural catheters. This technique for analgesia has been demonstrated to be safe and effective both for inpatients and in the ambulatory surgery setting. These analgesic benefits,along with other potential benefits such as improved rehabilitation,(1,9) faster discharge(1,8) and improved patient satisfaction(8) should be weighed against the risks of peripheral nerve blocks(10-12) along with the costs to determine the ideal route of delivery of postoperative analgesia for each surgical patient.

ATTACHED FILES

A24_ASRA fig. 1.doc

A24_ASRA Fig 2.doc

A24_ASRA table 1.doc

Reg Anesth Pain Med 2004; 29(2):A24