Methods	Regional anaesthesia added to general anaesthesia versus general anaesthesia
Participants	60 patients undergoing elective colonic surgery
Interventions	General anaesthesia for all participants with thiopental, fentanyl, nitrous oxide, enflurane and vecuronium The catheter was inserted with its tip at a level responding to the middle of the planned incision (n = 45). 4 mL of 0.5% bupivacaine, followed by 0.25% bupivacaine at 4 to 6 mL/h for 48 hours (n = 15) or epidural morphine 2 mg for 50 kg of body weight + 1 mg for each additional 10 kg of body weight daily for 48 hours (n = 15) or epidural morphine 2 to 6 mg/d as a continuous infusion for 48 hours (n = 15) IM oxycodone 0.15 mg/kg (n = 15)
Outcomes	Mortality in hospital, taken as zero to 30 days
Notes