To secure an intact airway is an important goal for the safety of patient. Sometime unrecognized or unanticipated difficult airway may lead to unexpected bad outcome like hypoxic brain damage or death. The aim and objective of this study is to predict difficult laryngoscopy using Modified Mallampati classification and Upper lip bite test as methods of airway assessment and to confirm the above findings with Cormack and Lehane grading. These tests will be used in combination to assess their sensitivity and specificity in order to determine their positive predictive value and negative predictive value.
Material and methodology: The preoperative airway assessment was conducted using both the screening tests, Modified Mallampatti test and the Upper lip bite test. Modified Mallampatti test grade III or IV and Upper lip bite test grade III were considered as predictors of difficult intubation. Intubation was considered difficult if the view on laryngoscopy was Cormack and Lehane grade III or IV. The results were evaluated on the basis of sensitivity, specificity, positive and negative predictive value of these tests.
Results: The Modified Malampati test has higher sensitivity of 71.43% and negative predictive value 97.65% resulting as better individual test for predicting difficulty for intubation than by Upper lip bite test with sensitivity of 28.57% and negative predictive value of 94.79%. This means that several patients with difficult intubation will not be identified by Upper lip bite test.