Comparison of intrathecal isobaric bupivacaine-morphine and ropivacaine-morphine for Caesarean delivery.

BACKGROUND: This study was designed to evaluate the effects of intrathecal isobaric bupivacaine 0.5% plus morphine and isobaric ropivacaine 0.5% plus morphine combinations in women undergoing Caesarean deliveries.

METHOD: Twenty-five parturients received ropivacaine 15 mg and morphine 150 micro g (RM group) and twenty-five parturients received bupivacaine 15 mg and morphine 150 micro g (BM group) for spinal anaesthesia. Sensory and motor block, haemodynamics, postoperative analgesia, fetal outcomes, and side-effects were evaluated.

RESULTS: Intrathecal bupivacaine-morphine and ropivacaine-morphine provided effective sensory anaesthesia and motor block. Time to reach complete motor block was shorter and time to complete recovery from motor block was longer in the BM group than the RM group (P<0.05). The time to regression of two dermatomes and time for the block to recede to the S2 dermatome were similar in both groups (P>0.05). Time to first complaint of pain and the mean total consumption of tenoxicam were similar in both groups (P>0.05). APGAR scores at 1 and 5 min were similar in the two groups, as were mean umbilical blood pH values (P>0.05). Hypotension and pruritus were the most common side-effects in both groups during the operation.

CONCLUSION: Intrathecal isobaric ropivacaine 0.5% 15 mg plus morphine 150 micro g provides sufficient anaesthesia for Caesarean delivery. The ropivacaine-morphine combination resulted in shorter motor block, similar sensory and postoperative analgesia.