Comparison of Effectiveness of Meperidine, Doxapram, and Fentanyl on Postanesthetic Shivering

Background : Shivering is a common postanesthetic complication. Because all shivering patients feel uncomfortable and increase oxygen consumption, various attempts have been made to prevent its occurrence or to control it. Among the pharmacological methods of treating shivering, meperidine has been known to be the most effective. This study was designed to evaluate whether there was any difference among meperidine, fentanyl, doxapram and normal saline in the treatment of post-anesthetic shivering. Methods : Forty patients (ASA class I or II) who showed postoperative shivering were randomly assigned into four groups(n=10): Normal saline group: normal saline 5 ml, Doxapram group: doxapram 1.5 mg/kg, Meperidine group: meperidine 25 mg, Fentanyl group: fentanyl 25 g. And all patients received routine care: oxygen by T-piece and heat-reflective blanketrol (cincinati Subzero, U.S.A.). Evaluation of the state of shivering was done every 5 minutes from the beginning of the treatment by the same investigator who had injected the drugs intravenously for treatment of shivering. The age, sex, weight and duration of surgery were recorded. Results: There were no significant statistical differences in age, sex, weight and duration of surgery among the four groups. By 5 minutes, 90% of doxapram group and 30% of meperidine group had stopped shivering. By 10 minutes, 90% of doxapram group and 70% of meperidine group had stopped shivering. But in fentanyl and normal saline group, only 20% had stoppd shivering by 10 minutes. Conclusions: We conclude that both meperidine and doxapram are effective on post-anesthetic shivering. In cases of patient with respiratory depression, doxapram is especially effective because it stimulates the respiratory center. (Korean J Anesthesiol 1998; 34: 389∼393)