Effects of thermal softening of endotracheal tubes on postoperative sore throat: A randomized double-blinded trial.

Yu, Je Hyuk; Paik, Hye-Sun; Ryu, Ho Geol; Lee, Hannah

BACKGROUND Postoperative throat complications after intubation are undesirable but frequent outcomes. A randomized, double-blinded study was performed to determine whether thermal softening of endotracheal tubes reduced throat complications after intubation. METHODS Patients (n= 196) undergoing nasal surgery were randomly allocated into the control group and thermal softening groups. Sore throat and hoarseness were evaluated 1 hour and 24 hours after extubation. The severity of sore throat was evaluated using the numeric rating scale. The primary outcome was the incidence of sore throat 1 hour after extubation and sore throat was defined as a painful or scratchy feeling in the throat. The secondary outcomes were the incidence of hoarseness 1 hour after extubation, the incidence of sore throat and hoarseness 24 hours after extubation, severity of sore throat, and vocal cord injuries. RESULTS The incidence of sore throat 1 hour after extubation was lower in the thermal softening group than in the control group (35.1% vs. 52.7%, P = 0.02). Moreover, thermal softening decreased the mean numeric rating scale score for sore throat in the thermal softening group by 10% an hour after extubation (thermal softening group, 1.29 (95% CI ,0.88-1.70) vs. control group, 2.33 (95% CI ,1.77-2.89); P < 0.01). At 24 hours after extubation, the incidence of sore throat (38.3% vs. 40.7%, P = 0.77) and hoarseness (34.0% vs. 35.2%, 0.95 (0.52-1.74), P = 0.74) were comparable between the two groups. CONCLUSIONS Intubation using endotracheal tubes with thermal softening significantly decreased the incidence of sore throat 1 hour after extubation when compared with endotracheal tubes without thermal softening.