Difficult Laryngoscopy Prediction Score for Intubation in Emergency Departments: A Retrospective Cohort Study

Difficult laryngoscopy is associated with difficult intubation, an increasing number of endotracheal intubation attempts, and adverse events. Clinical prediction of difficult airways in an emergency setting was limited in sensitivity and specificity. This study developed a new model for predicting difficult laryngoscopy in the emergency department.

This retrospective cohort study was conducted using an exploratory model at the Emergency Medicine of Ramathibodi Hospital. The study was conducted from June 2018 to July 2020. The eligibility criteria were an age of ≥15 years who undergo intubation in the emergency department. Difficult laryngoscopy was defined as a Cormack-Lehane grade 3 and above. The predictive model and score were developed by multivariable logistic regression analysis.

A total of 617 patients met the eligibility criteria; 83 (13.45%) had difficult laryngoscopy. Five independent factors were predictive of difficult laryngoscopy. Significant factors were M: limited mouth opening, O: presence of obstructed airway, N: poor neck mobility, T: large tongue, and H: short hypo-mental distance. The difficult laryngoscopy score had an accuracy of 89%. A score of >4 increased the likelihood ratio of difficult laryngoscopy by 7.62 times.

The MONTH Difficult Laryngoscopy Score of >4 was associated with difficult laryngoscopy.