Compatibility of the Drawover Vaporizer With Military Field Ventilators

Abstract

For far-forward resuscitative care for combat trauma casualties, the field anesthesia machine best suited is the Universal Portable Anesthesia Complete (UPAC, Datex Ohmeda, GE Healthcare). However, no provision was made for mechanical ventilation. Historically the Impact Uni-Vent 754 ventilator (Impact Instrumentation, Zoll Medical Corp) was used to provide hands-free ventilation but has limitations. There are 3 other field-capable ventilators that could fill the gap, but no known published research studies exist that examine the compatibility of these ventilators with the UPAC. The research question of this experimental, crossover design study was: Are there operational differences in the Impact 754, Impact Uni-Vent 731, Hamilton-T1 (Hamilton Medical Inc), and second-generation Simplified Automated Ventilator (SAVe II, AutoMedx) ventilators' performance relative to tidal volumes, rates, and inhaled anesthetic concentrations when used with the UPAC? The Impact 754 was most accurate (P<.05), followed by the Impact 731, and Hamilton-T1, and the SAVe II was the least accurate related to minute ventilation comparisons. Each ventilator demonstrated effective inhaled anesthetic delivery (r=0.97-0.99). Data analysis results demonstrated statistical and clinical significance in the reliability of the tested ventilators to deliver set volumes and rates while delivering predictable and accurate amounts of volatile anesthetic.

Keywords: Combat anesthesia; Forward Resuscitative Surgical Team; Universal Portable Anesthesia Complete; drawover; field ventilator.