Motor block during patient-controlled epidural analgesia with ropivacaine or ropivacaine/fentanyl after intrathecal bupivacaine for Caesarean section

Abstract

We compared patient-controlled epidural analgesia (PCEA) with ropivacaine alone or combined with fentanyl in terms of analgesic efficacy, motor weakness and side-effects in patients who had received spinal anaesthesia for elective Caesarean section. ASA I patients received combined spinal-epidural anaesthesia and were randomly assigned, in a double-blind study, into two groups after operation: group R (n=23) received PCEA ropivacaine 0.1%, bolus 5 mg, lockout 15 min, 3 mg h-1 background infusion, and group RF (n=24) received PCEA 0.1% ropivacaine/fentanyl 2 μg ml-1 at identical settings. Pain and satisfaction on a 100 mm visual analogue scale (VAS) and side-effects were noted. Incidence of motor weakness (Bromage grade I or higher) was 48% (11/23) at 8 h in group R compared with 13% (3/24) in group RF (P=0.025). Pain scores on movement were lower in group RF at 8 and 12 h and at rest at 6 and 8 h (P<0.05 for each comparison). Analgesic consumption was less in RF (P=0.041), but there was no difference in time to first request for supplementary analgesia. Patient satisfaction with postoperative analgesia (mean (SD)) was higher in RF (79 (23) vs 57 (29) mm, P=0.045). Caution should be exercised using ropivacaine PCEA after spinal bupivacaine for Caesarean section, because its reputed motor-sparing property may be unreliable.