Abstract
Objective: To evaluate the diagnostic significance of Mallampatti grading of difficult airway for endotracheal intubation.
Methods: This was a prospective blinded study conducted in 249 patients. The demographic data was collected from patient’s attendant. Patients were evaluated for Modified Mallampatti grading (MMG) before surgery. An experienced anesthesiologist, not aware of the recorded pre-operative airway evaluation, performed the laryngoscopy and grading as per Cormack and Lehane’s classification.
Results: Among study population, most of the patients were with Mallampatti grading 1 (47.4%). The prevalence of difficult airway for endotracheal intubation was 17.7%. For difficult intubation, the diagnostic value of Mallampatti grading was significant (AUC=0.63, p=0.006) but with low sensitivity 34.09% (95% CI=20.5-49.9) and high specificity 88.78% (95% CI=83.6-92.8). The positive likelihood ratio (+LR), negative likelihood ratio (-LR), positive predictive value (+PV) and negative predictive value (-PV) were found to be 3.04%, 0.74%, 39.5% and 86.3%, respectively.
Conclusion: The predictor test MMG for DI has only poor to moderate discriminative power when used alone. No test has 100% sensitivity, and inevitably some difficult tracheal intubations are missed and some false positives may occur, but they should be as few as possible. Even with the varying results of the commonly used airway assessment tests we still use them, and every anesthesiologist should be familiar with the difficult airway algorithm.
Keywords: Difficult airway, Endotracheal intubation, Diagnostic significance, Mallampatti grading.
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Corresponding Author
Dr Lokendra Gupta
Senior Resident, Emergency Medicine, KGMU, Lucknow, UP, India
DOI: https://dx.doi.org/10.18535/jmscr/v7i7.87
