Comparison of upper-lip bite test with other four predictors for predicting difficulty in intubation

Background: Unanticipated difficult tracheal intubation remains a primary concern of anaesthesiologists. The aim of the present study was to compare upper-lip bite test (ULBT) with other four predictors namely modified Mallampati test (MMT), thyromental distance (TMD), sternomental distance (SMD) and interincisor distance (IID) for predicting difficulty in intubation. Methods: Airway assessment indices were evaluated and compared in 60 American Society of Anesthesiologists physical status Grade I and II patients undergoing general anaesthesia at a tertiary care teaching hospital in South India. The cut-off points for defining the difficult intubation (DI) were as follows: for ULBT, Class III; MMT, Classes 3 and 4; TMD