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 hyper angulated blade. We evaluate the efficacy of reducing POGO view to <50% when intubating patients with rigid cervical immobilization using CMACTM D blade.

METHODS: Adult patients were randomized to full (POGO 100%) or partial (POGO <50%) glottic view. A laryngoscopy was performed by advancing the tip of the D blade at vallecula. POGO 100% was achieved by exerting an upward force to displace epiglottis until a complete glottic opening extending from 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: Data from 104 patients were analyzed. 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 than with a full POGO.

TRIAL REGISTRATION: : The trial is registered at ClinicalTrial.gov (CT.gov identifier: NCT04833166).