Comparison of Acromio-Axillo-Suprasternal Notch Index with Combination of Modified Mallampati Score and Thyromental Distance in Predicting Difficult Visualization of Larynx

Sajina Silwal; Madindra Basnet; Arjun Gurung; Anil Shrestha; Binita Acharya

doi:10.59779/jiomnepal.1463

Comparison of Acromio-Axillo-Suprasternal Notch Index with Combination of Modified Mallampati Score and Thyromental Distance in Predicting Difficult Visualization of Larynx

Authors

Sajina Silwal Department of Anesthesiology, Maharajgunj Medical Campus, Tribhuvan University Teaching Hospital, Institute of Medicine, Kathmandu, Nepal
Madindra Basnet Nepal Cancer Hospital and Research Center, Lalitpur, Nepal
Arjun Gurung Department of Cardiothoracic and Vascular Anesthesiology, Maharajgunj Medical Campus, Manmohan Cardiothoracic Vascular and Transplant Center, Institute of Medicine, Kathmandu, Nepal
Anil Shrestha Department of Anesthesiology, Maharajgunj Medical Campus, Tribhuvan University Teaching Hospital, Institute of Medicine, Kathmandu, Nepal
Binita Acharya Department of Anesthesiology, Maharajgunj Medical Campus, Tribhuvan University Teaching Hospital, Institute of Medicine, Kathmandu, Nepal

DOI:

https://doi.org/10.59779/jiomnepal.1463

Keywords:

Acromio-axillo-suprasternal notch index, Cormack-lehane grading, difficult laryngoscopy, modified mallampati score, thyromental distance

Abstract

Introduction
Various bedside clinical tests, singly or in combinations are used to predict difficult airway. This study aimed to compare Acromio-axillo-suprasternal notch index with combination of Modified Mallampati score and thyromental distance to predict difficult visualization of larynx by direct laryngoscopy.
Methods
This prospective, analytical study included 142 patients scheduled for elective surgery requiring general anesthesia with endotracheal intubation. Modified mallampati score, thyromental distance and Acromio-axillo suprasternal notch index were assessed preoperatively. In operation theatres, laryngoscopy was done and Cormack- Lehane grading was taken as standard for prediction of difficult visualization of larynx. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy and area under curve of Acromio-axillo-suprasternal notch index was compared with combination of Modified Mallampati score and thyromental distance.
Results
The overall incidence of difficult laryngoscopy, defined by Cormack- Lehane III and IV was 17.6%. The combined use of Modified Mallampati score and thyromental distance demonstrated a sensitivity of 80%, specificity of 85.5%, PPV of 54.1%, NPV of 95.2% and an overall accuracy of 84.5% (p=0.001). The sensitivity, specificity, PPV, NPV and accuracy of Acromio-axillo-suprasternal notch index was 84%, 88.9%, 61.8%, 96.3% and 88% respectively(p=0.001). Likewise, the AUC of Acromio-axillo-suprasternal notch index was (AUC=0.88; 95% CI, 0.82-0.93, p<0.001) whereas AUC of combination of Modified Mallampati score and thyromental distance was (AUC= 0.82; 95%CI, 0.75- 0.89, p< 0.001) which was comparable.
Conclusion
Acromio-axillo-suprasternal notch index is equivalent to combination of Modified Mallampati score and thyromental distance in predicting difficult visualization of larynx.