Comparison of Modified Mallampati Classification in Supine and Sitting Positions to Predict Difficult Tracheal Intubation in Diabetic Patients

Abstract

Background: Airway management of patients with long-standing diabetes poses a major challenge for anaesthesiologists due to stiff joint syndrome affecting the atlanto-occipital joint. In certain cases requiring immobilization, the Mallampati test must often be performed in the supine position for obvious reasons. Objectives: Hence, we determined the diagnostic precision (sensitivity and specificity) of the modified Mallampati test in sitting and supine positions among the diabetic population in predicting difficult tracheal intubation. Methods: A single-center prospective observational study on adult diabetic patients undergoing general anesthesia and orotracheal intubation was carried out. An observer recorded the modified Mallampati in the sitting posture during the pre-anesthetic examination. The Mallampati in the supine position was determined while in the operating room, and the difficulty of intubation was noted, and diagnostic precision was calculated. The main objective was to predict a difficult airway by calculating the sensitivity, specificity, positive predictive value, and negative predictive value. Results: Out of the 150 participants, Mallampati grading in a sitting position was correctly able to identify 42.5% of difficult intubation cases, whereas it was 97.5% with Mallampati in the supine position. Mallampati grading in the sitting position was able to correctly identify 89.1% of easy intubation cases, which was 63.6% with Mallampati in the supine position. The correlation of Mallampati in the supine position with CL grading was statistically significant (P < 0.001). Conclusions: Among diabetic patients, the modified Mallampati test in the supine position can be considered a more accurate and sensitive predictor of difficult intubation than the sitting posture.