The efficacy of ketamine for the treatment of postoperative shivering

BACKGROUND: There are few reports on the utility of ketamine for the prevention of postoperative shivering. We thus established the efficacy of two doses of ketamine compared with meperidine for the treatment of postoperative shivering. METHODS: This is a prospective, randomized double-blind study involving 90 ASA I-II patients after general anesthesia. Patients with shivering grade 3-4 were allocated to receive either meperidine 25 mg, ketamine 0.5 mg/kg, or ketamine 0.75 mg/kg IV. Shivering and side effects were monitored at set time intervals. RESULTS: Shivering grades for the first 4 min after treatment were lower in the ketamine groups; however, nystagmus and feeling like "walking in space" was experienced with both doses of ketamine. CONCLUSION: Ketamine 0.5-0.75 mg/kg is more rapid than meperidine (25 mg) for the reduction of postoperative shivering, but the side effect profile may limit its usefulness.