Oral Magnesium Lozenge Reduces Postoperative Sore Throat

Abstract

Background: Postoperative sore throat (POST) is an undesirable complaint after orotracheal intubation. Magnesium is a noncompetitive N-methyl-D-aspartate receptor antagonist thought to be involved in the modulation of pain. The present study aimed to investigate the effect of preoperative administration of oral magnesium lozenge on POST. Methods: Seventy patients undergoing orthopedic surgery were randomly allocated into two groups, to either receive placebo (control) or magnesium lozenges (magnesium) to be dissolved by sucking 30 min preoperatively. 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 secondary outcome was the severity of POST at four evaluation timepoints postoperatively. Results: The incidence of POST at 4 h was higher in control group than in magnesium group (95% CI: 26%, 14 -42%; P ϭ 0.032). The highest incidence of POST occurred at the second hour after surgery, with the rate of 23% in the magnesium group and 57% in the control group (95% CI: 34%, 20 -51%; P ϭ 0.007). The severity of POST was significantly lower in the magnesium group at 0 (P ϭ 0.007) and 2 h (P ϭ 0.002). The incidences of POST at 0 and 24 h and severity scores at 4 and 24 h were not significantly different between the groups. Conclusions: The administration of magnesium lozenge 30 min preoperatively is effective to reduce both incidence and severity of POST in the immediate postoperative period.

Postoperative sore throat prevention in ambulatory surgery: A comparison between preoperative aspirin and magnesium sulfate gargle – a prospective, randomized, double-blind study

“…In another placebo-controlled study, Borazan et al . [19] found that oral magnesium lozenges had significantly reduced the severity and incidence of POST. In our study, we have found that magnesium gargle, whereas compared with aspirin gargle, had more effectively reduced the incidence and severity of POST after GA at 2 nd and 4 th h ( P = 0.042 and P = 0.039 respectively).…”

“…[16] Again preoperative magnesium (N-methyl-D-aspartate receptor antagonist [NMDA]) lozenge effectively reduces both incidence and severity of POST. [19] Topically applied magnesium sulfate is famous for its therapeutic application on tissue suffering from thrombophlebitis as well as it has a preventive role in the similar conditions. [20]…”

The effects of water lubrication of tracheal tubes on post-intubation airway complications: study protocol for a randomized controlled trial

“…We thought that if lubricating tracheal tubes using water was effective in reducing airway injuries caused by intubation, it may primarily affect the incidence of postoperative sore throat, so we consider this as the primary outcome of our trial. We evaluate sore throat at several time points because it is known to occur within 24 h after surgery with varying incidence and severity [17, 20]. Because we hypothesized that lubricating tracheal tubes using water would have no advantage for reducing postoperative sore throat, we will compare its incidence in a noninferiority manner.…”

“…The severity of sore throat is evaluated using a four-point scale as follows: none, no sore throat; mild, complained of sore throat only upon inquiry; moderate, complained of sore throat without inquiry; severe, change of voice or hoarseness associated with throat pain [17]. Hoarseness is defined as a subjective symptom that is different from the previous voice quality of the patient [18].…”

“…Assuming the incidence of 57% in a previous study [17], 135 patients are required in each group to obtain 80% statistical power, 5% risk of type-I error, and 15% noninferiority margin. The margin was determined based on our clinical judgment that the incidence of postoperative sore throat is relatively high (50–60%), so the difference within 15% in the incidence would be considered clinically noninferior.…”