Technical problems and side effects associated with continuous intrathecal or epidural post-operative analgesia in patients undergoing hip arthroplasty

Abstract

Fifty-five patients undergoing hip arthroplasty under spinal anaesthesia (4 ml of 0.5% plain bupivacaine) were randomized to receive post-operative analgesia either using an intrathecal or an epidural catheter. Associated technical problems and side effects were studied. In both groups per-operative analgesia was achieved with intrathecal 0.5% plain bupivacaine, 4 ml. In the intrathecal infusion group a bolus dose of 100 micrograms morphine was injected through a spinal 28 gauge catheter followed by a 24 h infusion of 200 micrograms morphine (8.3 micrograms h-1). In the epidural infusion group a bolus dose of 2 mg of morphine was injected before the epidural 24 h infusion was started (morphine 200 micrograms h-1 + 0.25% bupivacaine 4 ml h-1). There were 10 catheter failures (two could not be inserted) in the intrathecal group and one in the epidural group. Three epidural catheter infusions failed due to other technical problems. The number of side effects was 21 in the remaining spinal group (n = 20) and 18 in the 20 epidural group patients with successful infusions. One patient in the spinal catheter group developed postdural puncture headache. For post-operative pain relief the patients in the epidural group needed less supplementary intramuscular oxycodone (five doses/four patients) than the spinal group (17 doses/nine patients) (P < 0.05).