If a randomized patient experiences an unexpected situation that requires a cabin pressurization of 1000 feet above sea level or less at any point in the flight (either prior to or after measurement of tracheal tube cuff pressure at cruising altitude), the paramedic may request the pilot to pressurize the cabin according to patient requirements. If any medical condition or aviation situation requires deviation from the study protocol, management of the medical condition or aviation situation shall take precedence, and the patient may be withdrawn from the study. If a patient is randomized but does not complete the study, the patient will be withdrawn from the study, and the reasons will be reported in the "paramedic #1 data collection sheet". The patient will not included in the analysis of changes in tracheal tube cuff pressure if all pressure measurements were not completed, but the reason(s) for study termination will be reported.