Effect of Laryngoscope Blade Size on First Pass Success of Tracheal Intubation in Critically Ill Adults

Kevin R Landefeld; Seiji Koike; Ran Ran; Matthew W Semler; Christopher Barnes; Susan B Stempek; David R Janz; Todd W Rice; Derek W Russell; Wesley H Self; Derek Vonderhaar; Jason R West; Jonathan D Casey; Akram Khan

doi:10.1097/CCE.0000000000000855

Effect of Laryngoscope Blade Size on First Pass Success of Tracheal Intubation in Critically Ill Adults

Crit Care Explor. 2023 Mar 6;5(3):e0855. doi: 10.1097/CCE.0000000000000855. eCollection 2023 Mar.

Authors

Affiliations

¹ Department of Medicine, Division of Pulmonary, Allergy, and Critical Care Medicine, Oregon Health and Science University School of Medicine, Portland, OR.
² Biostatistics and Design Program, Oregon Health and Science University, Portland, OR.
³ Division of Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University School of Medicine, Nashville, TN.
⁴ Department of Anesthesiology and Pain Medicine, University of Washington, Seattle, WA.
⁵ Department of Medicine, Division of Pulmonary & Critical Care Medicine, Lahey Hospital & Medical Center, Burlington, MA.
⁶ University Medical Center New Orleans, New Orleans, LA.
⁷ Department of Medicine, Division of Pulmonary, Allergy & Critical Care Medicine, University of Alabama at Birmingham Heersink School of Medicine, Birmingham, AL.
⁸ Department of Veteran's Affairs, Birmingham Veteran's Affairs Medical Center, Birmingham, AL.
⁹ Vanderbilt Institute for Clinical and Translational Research and Department of Emergency Medicine, Vanderbilt University Medical Center, Nashville, TN.
¹⁰ Department of Pulmonary and Critical Care Medicine, Ochsner Health System New Orleans, New Orleans, LA.
¹¹ Department of Emergency Medicine, New York Health + Hospitals | Lincoln, New York, NY.

Abstract

Tracheal intubation (TI) is a common procedure in critical care, often performed with a Macintosh curved blade used for direct laryngoscopy (DL). Minimal evidence informs the choice between Macintosh blade sizes during TI. We hypothesized that Macintosh 4 blade would have higher first-attempt success than Macintosh 3 blade during DL.

Design: Retrospective analysis using a propensity score and inverse probability weighting of data from six prior multicenter randomized trials.

Setting and participants: Adult patients who underwent nonelective TI at participating emergency departments and ICUs. We compared the first-pass success of TI with DL in subjects intubated with a size 4 Macintosh blade on the first TI attempt to subjects with a size 3 Macintosh blade on the first TI attempt.

Main results: Among 979 subjects, 592 (60.5%) had TI using DL with a Macintosh blade, of whom 362 (37%) were intubated with a size 4 blade and 222 (22.7%) with a size 3 blade. We used inverse probability weighting with a propensity score for analyzing data. We found that patients intubated with a size 4 blade had a worse (higher) Cormack-Lehane grade of glottic view than patients intubated with a size 3 blade (adjusted odds ratio [aOR], 1.458; 95% CI, 1.064-2.003; p = 0.02). Patients intubated with a size 4 blade had a lower first pass success than those with a size 3 blade (71.1% vs 81.2%; aOR, 0.566; 95% CI, 0.372-0.850; p = 0.01).

Conclusions and relevance: In critically ill adults undergoing TI using DL with a Macintosh blade, patients intubated using a size 4 blade on first attempt had a worse glottic view and a lower first pass success than patients intubated with a size 3 Macintosh blade. Further prospective studies are needed to examine the optimal approach to selecting laryngoscope blade size during TI of critically ill adults.

Keywords: airway management; critical care; laryngoscopesize; laryngoscopy; mechanical ventilation; tracheal intubation.

Abstract

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