Combined spinal-epidural improved intra-operative analgesia and reduced pain with cough in the immediate postoperative period. The addition of fentanyl to subarachnoid morphine and bupivacaine decreased the need for additional i.v. fentanyl and epidural bupivacaine analgesia.

Compared to IT morphine alone, triple IT combination administered as part of CSE provided better intraoperative analgesia, but conferred no benefit with regards to postoperative analgesia.

Although pain is a predictable consequence of surgery, effective intraoperative nociceptive blockade through multimodal analgesia, including spinal analgesics, may attenuate central pain pathway sensitisation and lower pain intensity after major abdominal surgery 1 .Combined spinal-epidural-general anaesthesia can confer certain advantages compared to conventional general anaesthesia: spinal anaesthesia provides relaxation and analgesia, the epidural catheter prolongs anaesthesia and improves postoperative analgesia while general anaesthesia provides unconsciousness and controlled ventilation, thus providing excellent operating conditions for the surgeon 2 . The choice of neuraxial (subarachnoid or epidural) and systemic agents may affect intraoperative and postoperative pain and perhaps alter postoperative outcome. Subarachnoid fentanyl (lipidsoluble, quick onset) and preservative-free morphine (water-soluble, slower onset, long duration) combined with a small dose of subarachnoid bupivacaine has SUMMARy This study was designed to compare the efficacy of subarachnoid morphine alone or in combination with bupivacaine and fentanyl for combined spinal-epidural analgesia in colorectal surgery. This is a prospective, randomised, doubleblind clinical trial. Sixty patients undergoing low anterior resection were assigned to one of three groups: subarachnoid morphine, bupivacaine and fentanyl, subarachnoid morphine and bupivacaine or subarachnoid morphine only. Epidural catheter placement and subarachnoid injection were done via a combined spinal-epidural Epistar ® needle at L2-3. The epidural catheter was used for scheduled intraoperative bupivacaine and intermittent postoperative bupivacaine and morphine administration. Intraoperative epidural bupivacaine, intraoperative intravenous fentanyl use, time to first analgesia request, postoperative visual analogue scale pain scores, tramadol requirements and side-effects were recorded for 72 hours. Postoperative analgesia was comparable in all groups. Intraoperative fentanyl and bupivacaine consumption was lowest in the morphine, bupivacaine and fentanyl group. Time to first analgesia request was longer in the morphine, bupivacaine and fentanyl compared to the morphine group (P=0.009). Tramadol use was lower in the morphine and bupivacaine group compared to morphine, bupivacaine and fentanyl (P=0.017) on postoperative day two. There were no significant adverse effects. All patients ambulated the morning after surgery. The addition of bupivacaine and fentanyl to subarachnoid morphine did not confer any advantage on postoperative visual analogue scale scores and tramadol use, but lowered the need for additional intraoperative intravenous fentanyl and epidural bupivacaine and prolonged the time to first analgesia request.

The two CSE techniques did not differ with regards to the procedure time and patient's preference. Procedure time correlated with body habitus, spinal landmarks and the anatomy in the SST group.