Endotracheal Tube Intracuff Pressure Changes in Patients Transported by a Helicopter Emergency Medical Service: A Prospective Observational Study.

ABSTRACT

OBJECTIVE: The pressure within an endotracheal tube cuff is of particular importance in helicopter emergency medical services (HEMS) transport because the unpressurized cabin is subjected to decreases in atmospheric pressure. This can cause the cuff to overinflate and may be associated with clinical complications. We sought to evaluate endotracheal tube cuff pressure changes among intubated patients during HEMS transport. METHODS: A prospective observational study was performed including adult patients who were intubated and transported by helicopter between April 2017 and October 2018. Cuff pressures were measured before, during, and after HEMS transport with a commercial manometer. RESULTS: A total of 208 patients were included. The median maximum flight altitude was 3,000 (interquartile range [IQR], 2,000-5,000) ft. The median initial cuff pressure before takeoff was 35 (IQR, 24-50) cm H2O, which increased to 50 (IQR, 35-70) cm H2O at maximum altitude. A total of 169 (81.3%) patients had a cuff pressure > 30 cm H2O at maximum altitude. There was a moderate correlation between altitude and cuff pressure (r = 0.532, P < .001). CONCLUSIONS: Cuff pressure increased during HEMS transport, demonstrating the need for routine cuff pressure monitoring during flight. Further research is required to determine if exposure to transient increases in cuff pressure for short durations is clinically significant.