The effect of Tizanidine on postoperative shoulder pain in laparoscopic cholecystectomy with general anesthesia

Cholecystectomy is considered as the most important and relatively common postoperative pain control often begins in recovery room by using systemic narcotics that may have some side effects. The aim of this study is to evaluate the effect of premedication with oral tizanidine on pain relief after elective laparoscopic cholecystectomy. In this double-blinded clinical trial, 60 adults of American Society of Anesthesiologist physiologic state 1 and 2 scheduled for elective laparoscopic cholecystectomy under general anesthesia were studied and randomly divided in two study and control groups. Ninety minutes before the induction of anesthesia, patients received either 6 mg tizanidine (study group) or placebo (control group) orally. Then, the vital signs, pain intensity, duration of stay in recovery, and the analgesic consumption were measured and then compared in both groups during 24 h postoperatively. There was no significant difference in patient characteristics, with respect to age, weight, gender (P > 0.05). The pain score were significantly lower in study group at recovery, 6, 12 and 24 hours after surgery (P=0.01, P=0.009, P=0,005, P=0.03). The need for analgesic drugs was significantly lower I tizanidine group. (485.83 ± 52.33 mg vs.350.87± 20.86 mg),.There were no significant difference in hemodynamic parameters between two groups. Oral administration of 6 mg tizanidine before laparoscopic cholecystectomy reduces postoperative pain, opioid consumption.