Mallampati and Thyromental Tests to Predict Difficult Intubation

Two preoperative tests for prediction of difficult intubation are assessed. In this study a Mallampati test and a measurement of thyromental distance were performed at the preoperative visit of 379 patients whose tracheas were subsequently intubated under general anesthesia. These tests for prediction of difficult intubation had poor sensitivity and positive predictive value, but high specifity and negative predictive value. We concluded that these tests are of little value in predicting difficult intubation in adults, although the likelihood of an easy endotracheal intubation increases when they yield negative results.