Comparison of Upper Lip Bite Test with Modified Mallampati Score for better bedside difficult laryngoscopy predictability in elective surgeries

Abstract

Introduction: Accurate pre-operative assessment for predicted difficult intubation can ominously reduce the occurrence of unanticipated difficult intubation. The rationale of the study was to compare the Diagnostic Accuracy of Upper Lip Bite test and Modified Mallampati Score in the prediction of difficult laryngoscopy/airway.

Objective: To compare the Diagnostic Accuracy of Upper Lip Bite Test and Modified Mallampati Score in the prediction of difficult laryngoscopy/airway

Methodology: This prospective observational study was carried out Benazir Bhutto Hospital, Rawalpindi at department of Anesthesia, Intensive Care and Pain medicine, Benazir Bhutto Hospital, Rawalpindi from 1^st April, 2023 to 1^st October, 2023. . To eliminate the observer bias pre operative assessment of ULBT and MMS for each patient was assessed by single anaesthetist. Laryngoscopy and intubation were performed by an anaesthetist who had experience of more than three years who was blinded to pre-operative ULBT/MMS grade. Cormack Lehane score was noted and used as a marker of difficult laryngoscopy.

Results: For ULBT, the Sensitivity was 78.43%, Specificity was 47.06%, Positive predictive value was 53.33%, Negative predictive value was 74.55% and the Diagnostic Accuracy was 60.17%. When comparing the Modified Mallampati Score to the Cormack-Lehane Test, the Sensitivity was 91.23%, Specificity was 47.54%, PPV was 61.90%, NPV was 85.94% and the Diagnostic Accuracy was 68.64%.

Conclusion: The Modified Mallampati Score had a higher Diagnostic Accuracy when compared to the Upper Lip Bite Test.