The Optimal Concentration of Ropivacaine in Combination with Butorphanol 50micro gram/ml for Patient-Controlled Epidural Analgesia

Background: Opioids may be used in a dose-sparing capacity with local anesthetics to reduce the dose needed.This study examined the efficacy of different concentrations of ropivacaine combined with butorphanol 50μg/ml to provide postoperative analgesia.Methods: Sixty parturients were received epidural infusion with 0.075% ropivacaine (Group 1: n = 20), 0.1% ropivacaine (Group 2: n = 20) and 0.15% ropivacaine (Group 3: n = 20) in combination with butorphanol 50μg/ml using patient-controlled epidural analgesia (PCEA) after cesarean section.PCEA was started with basal infusion of 4 ml of PCEA solution and 4 ml of bolus infusion at 10 min of lockout interval.Using a visual analogue scale (VAS) assessed the degree of pain and incidences of side effects were checked.Results: Total infusion doses of ropivacaine were significantly higher in group 3, and butorphanol consumption were significantly lower in group 3 (P ＜ 0.05).The incidences of nausea, vomiting and sedation were significantly higher in group 1 (P ＜ 0.05).There were no significantly differences in VAS pain score and other side effects among the groups.Conclusions: This study suggests that 0.1% or 0.15% ropivacaine with butorphanol 50μg/ml for PCEA can provide the most effective analgesia with less side effects after cesarean section.(Korean J Anesthesiol 2002; 43: 749∼754)