Difficult Airway Characteristics Associated with First Attempt Failure at Intubation Using Video Laryngoscopy in the Intensive Care Unit.

<p><b>RATIONALE: </b>Video laryngoscopy has overcome the need to align the anatomic axes to obtain a view of the glottic opening in order to place a tracheal tube. However, despite this advantage, a large number of attempts are unsuccessful. There are no existing data on anatomic characteristics in critically ill patients associated with a failed first attempt at laryngoscopy when using video laryngoscopy.</p><p><b>OBJECTIVES: </b>To identify characteristics associated with first attempt failure at intubation when using video laryngoscopy in the intensive care unit.</p><p><b>METHODS: </b>This is an observational study of 906 consecutive patients intubated in the intensive care unit with a video laryngoscope between January 2012 and January 2016 in a single center academic medical intensive care unit. After each intubation the operator completed a data collection form, which included information on difficult airway characteristics, device used, and outcome of each attempt. Multivariable regression models were constructed to determine the difficult airway characteristics associated with a failed first attempt at intubation.</p><p><b>MEASUREMENTS AND MAIN RESULTS: </b>There were no significant differences in gender, age, reason for intubation, or device used between first attempt failures and first attempt successes. First attempt successes more commonly reported no difficult airway characteristics were present (23.9% 95% CI: 20.7-27.0% vs 13.3% 95% CI: 8.0-18.8%). In logistic regression analysis of the entire 906 patient database, blood in the airway (OR 2.63 95% CI: 1.64-4.20), airway edema (OR 2.85 95% CI: 1.48-5.45), and obesity (OR 1.59 95% CI: 1.08-2.32) were significantly associated with first attempt failure. Data collection on limited mouth opening and secretions began after the first 133 intubations and we fit a second logistic model to examine cases in which these additional difficult airway characteristics were collected. In this subset (n=773) the presence of blood (OR 2.73 95% CI: 1.60-4.64), cervical immobility (OR 3.34 95% CI 1.28-8.72), and airway edema (OR 3.10 95% CI 1.42-6.70) were associated with first attempt failure.</p><p><b>CONCLUSIONS: </b>In this single center study, presence of blood in the airway, airway edema, cervical immobility, and obesity are associated with higher odds of first attempt failure, when intubation was performed with video laryngoscopy in an intensive care unit.</p>