Background: Good airway management defines an anesthesiologist .Link between unanticipated difficulty during endotracheal intubation with anaesthetic morbidity and mortality has been proved. Therefore it becomes necessary to predict difficult intubation as accurately as possible. Upper lip bite test is one proposed tests to predict difficult intubation.

Objectives: To compare sensitivity, specificity, positive predictive value and negative predictive value of ULBT and MMT to predict difficulty in endotracheal intubation.

Methods: A prospective study was carried on 124 patients, both sexes aged between 18 yrs to 60 yrs scheduled for elective surgeries under general anaesthesia fulfilling inclusion and exclusion criteria.

Patient airway was evaluated by MMT and ULBT preoperatively. Predictors of difficult endotracheal intubation were assigned to MMT class III and IV, ULBT class III. After premedication and induction laryngoscopy was performed in sniffing position. The glottic view was graded according to the Cormack and Lehane classification. Difficult intubation was assigned to Patients of Cormack Lehane class III / IV.

Results: Incidence of difficult intubation in our study was found to be 17.7% i.e. 22 out of 124) .ULBT was found to be more sensitive and had higher positive predictive value. But, specificity and negative predictive value of both the tests were comparable.

Conclusions: ULBT is a better predictor of difficult endotracheal intubation when compared to MMT and both the tests are better predictors of easy intubations than of difficult intubation.

Keywords: Difficult intubation, Modified Mallampati Test, Upper Lip Bite Test, Cormack Lehan.

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Dr P.S. Indurkar

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