Preoperative amylmetacresol and dichlorobenzyl alcohol with lignocaine lozenge reduces postoperative sore throat following general anaesthesia using supraglottic airway devices: A double-blinded, randomised, placebo-controlled trial

BACKGROUND AND AIMS: Postoperative sore throat (POST) is an undesirable event reported in up to 62% of patients receiving general anaesthesia (GA). The incidence of POST following GA using a supraglottic airway device (SAD) is approximately 50%, with symptoms persisting up to 48 h. We examined the role of preoperative lozenges containing amylmetacresol and dichlorobenzyl alcohol (AMC/DCBA) with lignocaine (Strepsils(®) Max Plus) in reducing the incidence and intensity of POST following GA using SAD. METHODS: We conducted a prospective, double-blinded, randomised, placebo-controlled trial involving 88 adults receiving GA for elective surgery using SAD not exceeding 2 h. Patients received either Strepsils Max Plus (Strepsils-LA group) or a placebo before induction of GA. The incidence and intensity of sore throat, dysphagia and dysphonia was measured using the Verbal Rating Scale at 30 min (early) and at 24 h (late) after removal of SAD. RESULTS: Overall POST incidence was lower in the Strepsils-LA group (27.7% versus 56.8%, P = 0.007). Patients in the Strepsils-LA group reported a significantly lower incidence of early POST (14.9% versus 37.8%, P = 0.016) with a lower mean ± standard deviation intensity score (0.17 ± 0.43 versus 0.49 ± 0.69, P = 0.016). Although the overall incidence of dysphagia was lower (23.4% versus 48.6%, P = 0.016), more patients experienced dysphonia in the Strepsils-LA group. AMC/DCBA with lignocaine lozenges showed a relative risk reduction of 50% and a number needed to treat of 4 in reducing POST. CONCLUSION: AMC/DCBA with lignocaine lozenges administered before GA using SAD is a simple and safe method to reduce the incidence and severity of POST.