Effect of magnesium sulfate nebulization on the incidence of postoperative sore throat

Postoperative sore throat (POST) is a well-recognized complication after general anesthesia (GA). Numerous nonpharmacological and pharmacological measures have been used for attenuating POST with variable success. The present study was conducted to compare the efficiency of preoperative nebulization of normal saline and magnesium sulfate in reducing the incidence of POST following GA.

Following institutional ethical committee approval and written informed consent, a prospective randomized double-blinded study was conducted in 100 cases divided into two equal groups. Patients included in the study were of either gender belonging to American Society of Anesthesiologist (ASA) status 1 or 2 undergoing elective surgery of approximately 2 h or more duration requiring tracheal intubation. Patients in Group A are nebulized with 3 ml of normal saline and the patients in Group B are nebulized with 3 ml of 225 mg isotonic nebulized magnesium sulfate for 15 min, 5 min before induction of anesthesia. The incidence of POST at rest and on swallowing and any undue complaints at 0, 2, 4, and 24 h in the postoperative period are evaluated.

There is no significant difference in POST at rest during 0(th), 2(nd) and 4(th) h between normal saline and MgSO4. Significant difference is seen at 24(th) h, where MgSO4 lessens POST. There is no significant difference in POST on swallowing during 0(th) and 2(nd) h between normal saline and MgSO4. Significant difference is seen at 4(th) h, where MgSO4 has been shown to lessen POST.

MgSO4 significantly reduces the incidence of POST compared to normal saline.