Effective Continuous Infusion and Bolus Doses for Patient-controlled Epidural Analgesia Using Ropivacaine

Background: Epidural analgesia is often considered the most effective technique for providing pain relief after cesarean section. Epidural infusion of local anesthetics combined with opioids provides better analgesia and reduces unwanted side effects. This study examined the efficacy of patient-controlled epidural analgesia (PCEA) using 0.2% ropivacaine with butorphanol and compared the suitability of four different volumes of bolus dose (BD) and continuous background infusion (CBI). Methods: Sixty patients received 0.2% ropivacaine with 50 butorphanol by PCEA after cesarean section. These subjects were divided four groups according to volumes of BD and CBI (2 ml and 2 ml/hr: group 1; 3 ml and 3 ml/hr: group 2; 4 ml and 4 ml/hr: group 3 during 24 hours postoperatively. The visual analogue scale (VAS) was used to measure pain and the incidences of side effects were assessed. Results: The incidences of numbness of the lower extremities were significantly lower in group 1 (5%) than either group 2 (15%) or group 3 (15%) (both, P can provide a sufficient analgesic effect with fewer side effects after cesarean section.