Partial vs full glottic view with CMAC^TM D blade intubation of airway with simulated cervical spine injury: a randomized controlled trial

Purpose A previous study reported a shorter time to tracheal intubation by reducing percentage of glottic opening (POGO) view to <50% when intubating a normal adult airway using the GlidescopeTM blade. We evaluate the efficacy of reducing POGO to <50% when intubating patients with rigid cervical immobilization using CMACTM D blade.Methods One hundred and four adult patients were randomized to group POGO 100% or POGO <50% . Laryngoscopy was performed by advancing tip of the D blade at vallecula. POGO 100% was achieved by exerting upward force to displace epiglottis until glottic opening from the anterior commissure to inter arytenoid notch. POGO < 50% was acquired by withdrawing the D blade tip dorsally from vallecula. The primary outcome was time to intubation.Results The median time (IQR) to successful intubation was 29 (25–35) seconds for group POGO < 50% and 34 (28–40) seconds for group with POGO 100% (difference in medians, 5 seconds; 95% confidence interval, 2 to 8, p = 0.003). Complications were minor.Conclusion Using the CMACTM D blade with a reduced POGO in patients with cervical spine immobilization resulted in faster tracheal intubation.Trial registration The trial is registered at ClinicalTrial.gov (CT.gov identifier: NCT 04833166)