A comparison of preoperative airway assessment techniques: the modified Mallampati and the upper lip bite test.

Abstract

The purpose of this study was to compare the preoperative anesthetic airway evaluation methods of the modified Mallamapti test (MMT) and upper lip bite test (ULBT) with the direct laryngoscopic views obtained during tracheal intubation. Positive relationships were predicted for the MMT and ULBT with direct laryngoscopic view and between the MMT and ULBT. We assessed 50 patients' airways preoperatively by MMT and ULBT. Intraoperatively, laryngoscopic views were graded on the Cormack and Lehane scale. Descriptive statistics and correlations were computed. There was no relationship between the MMT and the ULBT and the Cormack and Lehane scale. There was a significant relationship between the ULBT and the Cormack and Lehane scale (r = 0.512; P <.001 ). The ULBT was superior to the MMT in every measure in this study: sensitivity (55% vs 11%), specificity (97% vs 75%), positive predictive value (83% vs 9%), and accuracy (90% vs 64%). The findings of this study support those of a previous study of the ULBT. Because of the ease of the ULBT and the promising results of this small study, we recommend further research with a larger, more diverse sample.