Double-blind randomized clinical trial study was used.
Ninety-nine patients of either sex undergoing elective surgery, under general anesthesia with endotracheal intubation, were recruited. Patients were randomized into three group, betamethasone gel, lidocaine jelly, or distilled water applied on the external surface of the tracheal tube. Patients were assessed for postoperative sore throat, cough, and hoarseness at 1, 6, and 24 hours after surgery.
In the first hour after surgery, the patients who received lidocaine or betamethasone had a significantly greater incidence of sore throat than the patients who received distilled water (RR = 2.9). In the sixth hour after surgery, there was a better effect of distilled water on reducing the incidence of sore throat, but no significant differences between the three groups were seen 24 hours after surgery. The incidence of cough was significantly lower in the distilled water group (P < .02) except at the first and 24 hours postoperative when the incidence of cough was similar. The incidence of hoarseness was similar between the three groups at 1, 6, and 24 hours after surgery.
In this study, the use of lidocaine gel and betamethasone does not reduce the incidence of sore throat or cough after intubation as much as distilled water.