A randomised, controlled trial of rectus sheath bupivacaine and intrathecal bupivacaine, without or with intrathecal morphine, vs. intrathecal bupivacaine and morphine after caesarean section

Summary We recruited 144 women of whom 131 underwent scheduled caesarean section and were allocated to intrathecal bupivacaine without (46) or with (47) morphine and postoperative rectus sheath bupivacaine; or intrathecal bupivacaine with morphine and postoperative rectus sheath saline (38). We measured postoperative pain with a 10‐point numeric rating scale. The mean (SD) areas under the curve for pain on movement during 48 postoperative hours were 273.5 (63.6), 223.8 (80.7) and 223.8 (80.7), respectively, p = 0.008. There was no difference between women who had intrathecal morphine with or without rectus sheath bupivacaine, p = 1. The equivalent values for pain at rest were 160.8 (64.7), 85.8 (79.4) and 82.8 (74.3), respectively, p < 0.001. There was no difference between women who had intrathecal morphine with or without rectus sheath bupivacaine, p = 0.98.