Oral Magnesium Lozenge Reduces Postoperative Sore Throat

Abstract

Background: Postoperative sore throat (POST) is an undesirable complaintafter orotracheal intubation. Magnesium is a noncompetitiveN-methyl-D-aspartate receptor antagonist thought to be involved in themodulation of pain. The present study aimed to investigate the effect ofpreoperative administration of oral magnesium lozenge on POST.Methods: Seventy patients undergoing orthopedic surgery were randomlyallocated into two groups, to either receive placebo (control) ormagnesium lozenges (magnesium) to be dissolved by sucking 30 minpreoperatively. Patients were assessed for incidence and severity(four-point scale, 0-3) of POST at 0, 2, 4, and 24 h postoperatively.The primary outcome was sore throat at 4 h after surgery. The secondaryoutcome was the severity of POST at four evaluation time-pointspostoperatively.Results: The incidence of POST at 4 h was higher in control group thanin magnesium group (95% CI: 26%, 14-42%; P = 0.032). The highestincidence of POST occurred at the second hour after surgery, with therate of 23% in the magnesium group and 57% in the control group (95%CI: 34%, 20-51%; P = 0.007). The severity of POST was significantlylower in the magnesium group at 0 (P = 0.007) and 2 h (P = 0.002). Theincidences of POST at 0 and 24 h and severity scores at 4 and 24 h werenot significantly different between the groups.Conclusions: The administration of magnesium lozenge 30 minpreoperatively is effective to reduce both incidence and severity ofPOST in the immediate postoperative period.