The Effect of Intravenous Magnesium Sulfate Versus Intravenous Sufentanil on the Duration of Analgesia and Postoperative Pain in Patients with Tibia Fracture

BACKGROUND In the recent decades controlling postoperative pain has become a popular topic as it leads to the patients' wellbeing and improved life quality, while it reduces the costs for both patients and medical facilities. OBJECTIVES This study aimed at comparing intravenous magnesium sulfate versus intravenous sufentanil on the duration of analgesia and postoperative pain in patients undergoing tibia fracture surgery. METHODS This double blind clinical trial study was performed on 70 candidates of tibia fractures between the ages of 18 and 55 years with American society of anesthesiologists (ASA) class I and II. The patients were randomly divided to 2 groups, 1 receiving magnesium sulfate (M) and another receiving sufentanil (S). Both of the groups underwent spinal anesthesia with 10 mg bupivacaine 0.5%. One hour after ensuring the sensorimotor blockade, in the S group 0.1 µg/kg/hour and in the M group 8 mg/kg/hour was diluted in 1 liter of Ringer's solution and infused. In this study, full weakness of the lower limb was considered as the sign of sensorimotor blockade initiation. The postoperative pain intensity was measured using the Visual Analog Scale (VAS), 0, 1, 4, 8, 16, and 24 hours after the end of anesthesia duration. In case of VAS ≥ 3, the patients received 0.3 mg/kg pethidine, intravenously. At last, the time of requesting the first narcotic drug and the total usage of pethidine were recorded. RESULTS AND CONCLUSIONS Sufentanil was found to be more effective than magnesium sulfate in reducing postoperative pain and the time of first narcotics request was later in patients receiving sufentanil (P < 0.05).