Early Identification of Circulatory Shock in Critical Care Transport

摘要

Recognizing and treating shock is essential to saving the lives of injured or ill war fighters. Current methods for diagnosing shock are unreliable and may lead to delayed treatment, further injury, or even death. This study will examine the feasibility of new methods of detecting shock using non-invasive devices during critical care transport. We tested point of care lactate and tissue oximetry devices under variations of environmental temperature, regional ischemia, and the austerities of the air medical environment. We simulated commonly encountered field conditions in the laboratory to determine the impact on tissue oximetry (StO2) and lactate. We simulated extremes of environmental temperature by performing a heat exposure test and a five-minute, cold-pressor test (ice-water forearm immersion). We simulated impaired circulatory states with a five-minute total occlusion of the forearm and a five-minute partial occlusion of the forearm. We evaluated differences in StO2 and lactate from baseline by repeated measures ANOVA. Following the laboratory testing we trained flight crews in the use of the devices and they performed testing on healthy volunteers during flight. We surveyed flight crewmembers regarding their perceptions of the testing devices using a five point Likert scale.