Author(s)
Elliot Morse
Keisha (Arielle) Best
Rose O'Loughlin
Paul Kwak
Mackenzie O'Connor
Joesph Connors
Shirley Gherson
Michele Santacatterina
Wenqing Yang
Anda Nyati
Milan Amin
Affiliation(s)
Abstract:
Background: The ability to obtain adequate exposure for direct laryngoscopy is important for patient care. Past literature has been inconsistent about identifying parameters most associated with difficult laryngeal exposure (DLE).
Methods: This prospective observational study enrolled patients scheduled for direct laryngoscopy at a single center institution. Prior to surgery, patients’ neck flexion/extension, thyromental distance, neck circumference, and interincisal difference were collected by an individual not involved in the surgery. Following direct laryngoscopy, surgeons recorded difficulty of exposure based on additional maneuvers necessary and adequacy of final laryngeal exposure, and any complications of intubation or laryngoscopy.
Results: A preliminary analysis modeling exposure complexity (ordered easy, medium, difficult) using a proportional-odds cumulative logit model in 36 participants was conducted. Interincisal distance was inversely associated with higher complexity (OR 0.879 per 1 mm; 95% CI 0.789–0.962; p = 0.010). There was no association for DLE for age (OR=0.984 per year; 0.928-1.041; p=0.581), BMI (OR=1.115 per unit; 0.942-1.342; p=0.218), maximal flexion (OR=1.265 per cm; 0.820-1.991; p=0.290), maximal extension (OR=0.793 per cm; 0.563-1.077; p=0.153), Mallampati score (OR=0.483 per 1 level; 0.126–1.565; p = 0.246), and female vs male (OR=0.711; 0.126-4.304; p=0.700).
Conclusion: Preliminary analysis shows that interincisal distance was predictive of DLE. Other patient demographic factors and anatomical measurements, including Mallampati score, were not shown to be predictive at this time. Identifying factors putting patients at risk for DLE can help prepare surgical teams more effectively, improve clinical management, optimize patient consent processes, and enable delivery of an increased quality of care.