The Science Journal of the American Association for Respiratory Care

2010 OPEN FORUM Abstracts


Thomas Blakeman1, Dario Rodriquez2, Michael Petro2, Warren Dorlac2, Richard Branson1; 1Department of Surgery, University of Cincinnati, Cincinnati, OH; 2Center for Sustainment of Trauma and Readiness Skills (CSTARS), Cincinnati, OH

Introduction: Mechanical ventilation in far forward military operations requires a device that is consistent, light weight and easy to use. We evaluated the SAVe (simplified automated ventilator) in a laboratory setting to determine performance characteristics. Methods: Three SAVe resuscitators were tested. Each was attached to a test lung with volume, pressure, and flow measured with a pneumotachometer. The SAVe model we tested provides only one respiratory rate (10) and one tidal volume (600 ml). Compliance and resistance of the test lung were varied to simulate varying patient conditions. Oxygen was entrained at the inlet and FIO2 was measured with a fast response oxygen analyzer at the airway. All measurements were made at sea level, 4000, 8000, 12,000, and 18,000 feet. Battery life was measured twice with each device by operating it to exhaustion. Results: Delivered tidal volume and inspiratory time varied when changing lung model conditions as well as between devices within the same lung model condition at sea level and at altitude. The largest reduction in tidal volume was at the lowest compliance. Inspiratory time also decreased with lower compliance. Data below shows tidal volume (SD) and inspiratory time with the three devices. Increases in altitude resulted in a 29% increase in delivered tidal volume between sea level and 18,000 ft. at the lowest compliance settings. Oxygen entrained at greater than 20 lpm resulted in the SAVe failing to cycle. Measured FIO2 was comparable to reported FIO2 although it decreased with simulated spontaneous breathing through the device. Conclusions: The SAVe resuscitator is a limited function device. Tidal volume delivery is inconsistent with decreased lung compliance and/or increased resistance. The set respiratory rate and tidal volume are not guaranteed under these conditions. During spontaneous breathing, room air is supplied to the patient. Entrainment of oxygen at greater than the recommended flow rate may result in ventilator malfunction. The SAVe could potentially be used for ventilatory support of carefully selected military casualties to replace manual ventilation, but caregivers must be aware of the limitations. Sponsored Research - None