ABSTRACT
OBJECTIVE: The objective of this study was to determine the effect of transitioning from direct laryngoscopy (DL) to video laryngoscopy (VL) on endotracheal intubation success overall and with enhanced precautions implemented during the COVID-19 pandemic. METHODS: We examined electronic transport records from Mayo Clinic Ambulance Service, a large advanced life support (ALS) provider serving rural, suburban, and urban areas in Minnesota and Wisconsin, USA. We determined the success of intubation attempts when using DL (March 10, 2018 to December 19, 2019), VL (December 20, 2019 to September 29, 2021), and VL with an enhanced COVID-19 guideline that restricted intubation to one attempt, performed by the most experienced clinician, who wore enhanced personal protective equipment (April 1 to December 18, 2020). Success rates at first attempt and after any attempt were assessed for association with type of laryngoscopy (VL vs DL) after adjusting for patient age group, patient weight, use of enhanced COVID-19 guideline, medical vs trauma patient, and ALS vs critical care clinician. A secondary analysis further adjusted for degree of glottic visualization. RESULTS: We identified 895 intubation attempts using DL and 893 intubation attempts using VL, which included 382 VL intubation attempts using the enhanced COVID-19 guideline. Success on first intubation attempt was 69.2% for encounters with DL, 82.9% overall with VL, and 83.2% with VL and enhanced COVID-19 protocols (DL vs overall VL: p < 0.001; COVID-19 vs non-COVID VL: p = 0.86). In multivariable analysis, use of VL was associate with higher odds of successful intubation on first attempt (odds ratio, 2.28; 95%CI, 1.73-3.01; p < 0.001) and on any attempt (odds ratio, 2.16; 95%CI, 1.58-2.96; p < 0.001) compared with DL. Inclusion of glottic visualization in the model resulted in a nonsignificant association between laryngoscopy type and successful first intubation (p = 0.41) and a significant association with the degree of glottic visualization (p < 0.001). CONCLUSIONS: VL is designed to improve glottic visualization. The use of VL by a large, U.S. multistate ALS ambulance service was associated with increased odds of successful first-pass and overall attempted intubation, which was mediated by better visualization of the glottis. COVID-19 protocols were not associated with success rates.