Postoperative analgesia in hip surgery. A controlled comparison of epidural buprenorphine with intramuscular morphine

In a randomised controlled trial, epidural buprenorphine was compared with intramuscular morphine for postoperative analgesia in patients after hip surgery. Analgesia was given on demand and consisted of epidural boluses of 60 micrograms of buprenorphine in 10 ml of normal saline or intramuscular morphine 0.15 mg/kg. Both forms of analgesia produced excellent pain relief as assessed by the linear analogue scoring system. In both quality and duration of pain relief, no significant difference was found between the two forms of analgesia, but the total dose of epidural buprenorphine required was five times less than the equivalent dose of intramuscular morphine. No side effects attributable to epidural buprenorphine administration were found. The authors conclude that low dose epidural buprenorphine provides an excellent alternative to intramuscular opiates for pain relief after hip surgery.