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DOI: http://dx.doi.org/10.21088/ijaa.2349.8471.7220.12

Abstract

Unanticipated difficult tracheal intubation is a significant source of morbidity and mortality in anesthesia practice. Identifying situations and patients at risk for airway management problems is a key to optimal care. This study compares the parameters described to identify a difficult intubation to look for the best predictors or combinations thereof. Materials and Methods: The preoperative airway assessment used multiple parameters like Mallampati test, Thyromental Distance, Head and neck Movement, Interincisor Gap, Lahey & McCormick Scale. The results were evaluated on the basis of sensitivity, specificity, positive and negative predictive value of these tests. During intubation a cumulative Intubation Difficulty Scale rating greater than 5 was used to
classify a patient as a difficult intubation to validate the scores. Results: Amongst all the parameters studied individually, the Upper lip bite test was found to have the highest sensitivity of 48.48% and specificity of
97.3%. When multiple parameters were taken into consideration, the combination of Mallampati score, Upper lip bite test and Neck circumference to thyromental distance ratio was found to have the highest sensitivity of 75.76% and specificity 91.12%. Conclusion: Application of multiple predictors can reduce the frequency of unanticipated difficulty and also unnecessary interventions related to over prediction of airway difficulty.

Keywords : Intubation; Difficult airway predictors; Mallampati test; Thyromental distance; Upper lip bite test; Height to thyromental distance ratio; Neck circumference to thyromental distance ratio; Multiple test predictors.

Corresponding Author : Reena Nayar