Comparison of intramuscular ketorolac and morphine in pain control after laparotomy.

Ketorolac, a prostaglandin synthetase-inhibiting analgesic, was compared with morphine for relief of pain after laparotomy for gynaecological surgery. Eighty patients were studied; they were given either ketorolac 30 mg intramuscularly followed by 10 mg 4-hourly as required, or morphine 10 mg intramuscularly 4-hourly as required, administered in a double-blind, randomised fashion. Pain scores (verbal and visual analogue) were recorded at baseline and assessed at 30 and 60 minutes and then hourly for 6 hours. Pain relief was measured at the same times. Pain and pain-relief scores were further assessed on the evening of day 1 and at 24 hours. Pain scores were similar in the two groups but pain-relief scores were better in the morphine group. A considerable number of patients suffered postoperative nausea and vomiting but there was no difference between the groups. One patient in the ketorolac group had unexplained hypotension. It is concluded that ketorolac can provide effective postoperative analgesia.