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Effects of simulated altitude on ventilator performance
Dario Rodriquez1, Richard D Branson, Warren Dorlac
1Center for Sustainment of Trauma and Readiness Skills, United States Air Force, Cincinnati, Ohio, USA.
The Journal of Trauma
|April 11, 2009
Summary
The Impact 754 ventilator accurately maintains tidal volume at simulated altitudes, while the LTV-1000 does not. This difference is critical for safe aeromedical transport of critically ill patients.
Area of Science:
- Aerospace Medicine
- Critical Care Medicine
- Biomedical Engineering
Background:
- Aeromedical transport of critically ill patients necessitates reliable medical equipment performance at varying altitudes.
- Evaluating the functional capacity of ventilators under simulated altitude conditions is crucial for patient safety.
Purpose of the Study:
- To assess the performance of two United States Air Force (USAF) ventilators during simulated aeromedical transport.
- To determine the impact of altitude on ventilator-delivered tidal volumes and other respiratory parameters.
Main Methods:
- Two USAF ventilators were tested in an altitude chamber across simulated altitudes from sea level to 15,000 feet.
- Ventilator performance was evaluated at various set tidal volumes, measuring airway pressure, flow, and volume delivery at each simulated altitude.
Main Results:
- The Impact 754 ventilator maintained set tidal volumes within 10% across all tested altitudes.
- The LTV-1000 ventilator demonstrated a significant increase in delivered tidal volume with rising altitude, up to 30% at 15,000 feet.
- Respiratory rate remained unaffected by altitude for both devices.
Conclusions:
- The Impact 754 effectively compensates for altitude-related barometric pressure changes, ensuring consistent tidal volume delivery.
- The LTV-1000's inability to compensate for altitude poses a risk of inaccurate ventilation, requiring clinical awareness.
- Understanding ventilator limitations is essential for safe and effective patient management during aeromedical evacuation.
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