Patient supplemented epidural analgesia after major abdominal surgery with bupivacaine/fentanyl or ropivacaine/fentanyl

Purpose: To compare analgesic efficacy and occurrence of motor block and other side effects during patient supplemented epidural analgesia (PSEA) with either ropivacaine/fentanyl or bupivacaine/fentanyl mixtures. Methods: In a prospective, randomized, double-blind study, 32 ASA 1-111 patients undergoing major abdominal surgery received an epidural catheter at the T₈- T₁₀, followed by integrated general epidural anesthesia. Postoperative epidural analgesia was provided using a patient controlled pump with either ropivacaine 0.2%/2 μg·ml^-1 fentanyl (group Ropivacaine, n = 16) or bupivacaine 0.125%/2 μg·ml^-1 fentanyl (group Bupivacaine, n = 16) [background infusion 4 - 6 ml·hr^-1, 1.5 ml Incremental Doses and 20 min lock out]. Verbal pain rating score, number of incremental doses, consumption of epidural analgesic solution and rescue analgesics, sedation (four-point scale), and pulse oximetry were recorded by a blind observer for 48 hr after surgery. Results: No differences in pain relief, motor block, degree of sedation, pulse oximetry and other side effects were observed between the two groups. The number of incremental doses and the volume of analgesic solution infused epidurally were higher in patients receiving the bupivacaine/fentanyl mixture (10 [0 - 52] I.D. and 236 [204 - 340] ml) than in patients receiving the ropivacaine/fentanyl solution (5 [0 - 50] I.D. and 208 [148 - 260] ml) (P=0.03 and P=0.05, respectively). Conclusion: Using a ropivacaine 0.2%/2 μg-ml^-1 fentanyl mixture for patient supplemented epidural analgesia after major abdominal surgery provided similar successful pain relief as bupivacaine 0.125%/2 μg·ml^-1 fentanyl, but patients receiving bupivacaine/fentanyl requested more supplemental.