Difficult Laryngeal Exposure in Microlaryngoscopy: Can it be Predicted Preoperatively?

The aim of the present study was to identify preoperative clinical predictors for difficult laryngeal exposure (DLE) and to define a simple grading system for laryngeal exposure. This is a prospective descriptive study carried out in a tertiary teaching hospital in South India. Patients above 18 years undergoing microlaryngoscopy had presurgical evaluation of 11 physical parameters. Grading of Modified Cormack–Lehane Score (MCLS) and rigid laryngoscopy were done during procedure. On logistic regression analysis, with a 95 % confidence interval (CI) MCLS was found to be a statistically significant predictor (odds ratio 12). With 90 % CI, neck circumference, atlanto-occipital extension and MCLS were significant (odds ratio of 4, 4, 12 respectively). Neck circumference of more than 34.25 cm and limited atlanto-occipital extension of less than 19.50, predicts difficult laryngeal exposure. A simple grading system for laryngeal exposure during microlaryngoscopy is being proposed. MCLS grade more than 2a done intra operatively correlates well with difficult intubation.