Emergency physicians cannot inflate or estimate endotracheal tube cuff pressure using standard techniques

Abstract

Study objectives: Tracheal necrosis and stenosis may result from an overinflated endotracheal tube cuff. Safe, appropriate pressure in endotracheal tube cuffs is considered to be between 15 and 25 cm H2O, pressures below normal capillary perfusion pressure. We seek to determine the ability of emergency medicine residents and attending physicians in accredited emergency medicine residency training programs to inflate an endotracheal tube cuff to appropriate pressure using standard syringe technique and assess appropriateness of pressure of previously inflated endotracheal tube cuffs by palpating the pilot balloon.Methods: This institutional review board–approved descriptive survey of resident and attending physicians in accredited emergency medicine residency training programs in New York City used a previously tested, tracheal simulation model with a 7.5-mm endotracheal tube with a high-volume low-pressure cuff (Mallinkrodt, St. Louis, MO). Using their choice of a 5-mL or 10-mL plastic syringe with standard Luer Lock (Beckton-Dickson, Franklin Lakes, NJ), participants inflated the endotracheal tube cuff by standard method of injecting air as they deemed appropriate in conjunction with palpating the pilot balloon to estimate cuff pressure. Subsequently, the endotracheal tube cuff pressure was measured using a highly sensitive and accurate analog manometer (Boehringer Laboratories, Norristown, PA). Later, participants palpated the pilot balloon of 9 endotracheal tubes with cuffs previously inflated to known pressures ranging from 0 to 120 cm H2O and reported whether the pressure was low, appropriate, or high.Results: Twenty-five resident physicians and 42 attending physicians from 5 emergency medicine residency training programs were surveyed. Only 0.4% (n=3) of participants inflated the cuff to a safe pressure; all were attending physicians. The average cuff pressure generated by emergency medicine attending physicians was greater than 98 cm H2O (attending physicians >93 cm H2O, residents >106 cm H2O). The true mean could not be determined because 57% (n=38) inflated to pressures greater than the upper limit of manometer sensitivity (>120 cm H2O). Using palpation, participants were only 33% sensitive detecting inappropriately inflated endotracheal tube cuffs (attending physicians 22% sensitive, residents 53% sensitive), and they were only 26% sensitive in detecting overinflated endotracheal tube cuffs (attending physicians 22%, residents 33%). Average experience as an attending emergency physician was 9 years; average experience as a resident was 2.1 years.Conclusion: This group of emergency physicians had little ability to inflate an endotracheal tube cuff to safe pressure, little ability to accurately estimate pressure of a previously inflated cuff using standard technique, and minimal ability to detect overinflated endotracheal tube cuffs. Nearly all inflated the cuff to dangerously high pressures. Clinicians should consider using devices that permit safe and accurate inflation and measurement of endotracheal tube cuff pressure rather than relying on standard palpation technique, which is potentially unsafe and highly inaccurate.