Online ISSN: 2515-8260

Comparison of Validity of Mallampati Test and Lower Jaw Protrusion Maneuver in Predicting Difficult Laryngoscopy and Intubation

Main Article Content

Priya.R1 , Sheela Verghese2 , Divya Madhu3*

Abstract

Background: Unanticipated difficult laryngoscopy and tracheal intubation is a main concern for the anesthesiologist. Failure to maintain a patent airway after the induction of general anesthesia is the most common cause of anesthesia-related morbidity and mortality. The morbidity associated with difficult intubation can be reduced if a difficult airway is anticipated preoperatively. There are many bedside tests to predict difficult airway. Aim and Objective: The main aim and objective of this study was to compare the sensitivity and specificity of the Mallampati technique with the lower jaw protrusion maneuver in predicting difficult laryngoscopy and tracheal intubation using the CormackLehane grading of intubation as the gold standard. Methods: A total of 275 patients undergoing thyroidectomy at MCH, Thiruvananthapuram, were selected as the study population. The airway was assessed by the Modified Mallampati Classification (MMC); classes III and IV were considered as predictors of difficult intubation. Lower Jaw Protrusion Maneuver Grades B and C were considered predictors of difficult intubation. A senior anesthesiologist with 5 years of experience assessed the laryngeal view by direct laryngoscopy using Cormack and Lehane grading. Grades 3 and 4 were considered difficult for laryngoscopy and intubation. The validity parameters, such as sensitivity, specificity, false positive and negative values, positive predictive value (PPV), and negative predictive value (NPV), were calculated. Results and Discussion: MMC: Sensitivity 63.6%, Specificity 98.4%, PPV 77.8%, NPV 96.9%, Accuracy 95.6% LJP: Sensitivity 72.7%, Specificity 98.4%, PPV 80%, NPV 97.6%, Accuracy 96.4% Conclusion: The lower jaw protrusion test has a higher level of accuracy, sensitivity, positive predictive value, and negative predictive value compared to the Mallampati test. Lower jaw protrusion appears to be a better choice for preoperative airway evaluation. So the LJP test can be added to routine preoperative evaluation of the airway, but it has the limitation that it cannot be performed in some patients, like the edentulous patients and patients with a low intellectual coefficient.

Article Details