A comparison of nefopam and clonidine for the prevention of postanaesthetic shivering: a comparative, double-blind and placebo-controlled dose-ranging study.

Postanaesthetic shivering is a frequent complication following general anaesthesia. The aim of this study was to compare the effectiveness of three doses of nefopam with clonidine and placebo in the prevention of postanaesthetic shivering. We studied 371 patients undergoing abdominal or orthopaedic surgery. Patients were allocated to one of five groups: Group A (n = 73) received 0.2 mg x kg(-1) nefopam, Group B (n = 75) 0.1 mg x kg(-1) nefopam, Group C (n = 76) 0.05 mg x kg(-1) nefopam, Group D (n = 73) 1.5 microg x kg(-1) clonidine, and Group E (n = 74) saline 0.9% as placebo. We found a significant reduction in the incidence of shivering in Group A compared to Group C and clonidine as well as to the placebo group. All active treatments reduced the incidence and the severity of shivering compared to placebo. At 5 min postoperatively clonidine-treated patients showed a significant decrease in MAP and a significantly lower Aldrete score compared to all other groups. No haemodynamic or sedative adverse events were observed in the nefopam-treated patients. The results of our study indicate that nefopam (0.2 mg x kg(-1)) is superior to clonidine (1.5 microg x kg(-1)) in the prophylaxis of postanaesthetic shivering and not accompanied by sedative or haemodynamic side-effects.