Comparison of the Effect of Dexamethasone, Midazolam, and Ondansetron Injection alone, or in Combination, and Placebo on the Severity of Shivering during and after Spinal Anesthesia in Orthopedic Operations of the Lower Limb

Considering the importance of shivering, as an important complication in patients after spinal anesthesia, in this study, we determined that the effectiveness of injection of three drugs dexamethasone, midazolam, and ondansetron, alone or in combination, on the shivering of patients. In this clinical trial study, 179 patients undergoing lower limb orthopedic surgeries referring to Kashani hospital, Isfahan, Iran, during the years 2006 to 2007 entered the study. Patients were divided into 5 groups receiving midazolam, ondansetron, dexamethasone, the combination of three drugs, and placebo. The severity of shivering and hemodynamic information were evaluated in patients. There was no significant difference between the groups according to the central and peripheral temperature at the time before the anesthesia and at 5, 10, 15, 20, 25, and 30 minutes after it (P > 0.050). There was a significant difference between the groups based on the severity of shivering during the first, second, third, and fourth fifteen minutes (P < 0.001); so that the shivering intensity was higher in the placebo group, and there was a significant difference between the other groups as well. (P < 0.001). Combination of the three drugs midazolam, dexamethasone, and ondansetron in orthopedic surgeries with spinal anesthesia can be associated with controlling of shivering.