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Updated: Aug 12, 2025

The Rigid Tube as an Alternative in Controlling the Problematic Airway
Published on: June 6, 2020
Partial vs full glottic view with CMACTM D blade intubation of airway with simulated cervical spine injury: a
Chao Chia Cheong1, Soon Yiu Ong1, Siu Min Lim1
1Department of Anaesthesiology, Faculty of Medicine, University Malaya, Kuala Lumpur, Malaysia.
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: NCT04833166).
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