EPIDURAL ANALGESIA WITH 4 MG OF MORPHINE FOLLOWING CESAREAN-SECTION -EFFECT OF INJECTED VOLUME

The efficacy and side effects of epidural bolus injection of 4 mg of m orphine in a volume of 2 ml, 10 ml, or 20 ml (groups I, II and III) fo r postoperative analgesia after caesarean section (60 patients) were e valuated. All patients had epidural anaesthesia established up to T4 l evel with 0.5% bupivacaine 18-20 ml, supplemented with 2% lidocaine wi th adrenalin, when necessary. Morphine 4 mg in either of the three vol umes was injected through the epidural catheter in random order after delivery of the baby. Six patients in each group reported no pain duri ng the 24-h follow-up period. No additional pain medication during the 24 h after surgery was required in 11, 14 and 10 patients in groups I , II and III, respectively. Most of the others managed with the additi on of a single dose of rectal ketoprofen. There were no differences in analgesic therapy between the groups. Pruritus was the most common ad verse effect (18/20, 19/20 and 18/20 in groups I, II and III, respecti vely). 10/20, 12/20 and 14/20 (N.S.) patients had nausea and vomiting in groups 1, II and III, respectively. Metoclopramide, prescribed for persistent nausea, was given to 4/20 patients in group I, 6/20 patient s in group II and 9/20 patients in group III (N.S.). After removal of the urinary catheter 7/20.patient in group III required carbachol for urinary retention compared to 3/20 and 4/20 patients in groups I and I l (N.S.). In this study a tenfold dilution of 4 mg of morphine did not influence the quality of analgesia after caesarean section or cause s tatistically significant differences in the appearance of side-effects .