Phillip J Wallace, Matthew L Hodgkinson, Lucas Ramagnano, Ramneek Singh Janjuha, Mariska J Andrade, Stephen S Cheung
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引用次数: 0
Abstract
Introduction: We studied field rewarming using a typical winter sleeping bag versus two heated hypothermia wrap systems in a semi-realistic lab simulation.
Methods: 10 participants (8 M, 2 F) were cooled to 36.1°C core temperature through 10.5-11.5°C water immersion, then performed 60 min of passive rewarming in 0°C air. The rewarming methods tested were: 1) a -9°C rated mummy-style Sleeping Bag; 2) Doctor Down Rescue Wrap; and 3) Thermal Yielding Vascular Airway Capsule (TYVAC) system; the latter two methods included vapor barriers and two heating pads. Rectal and skin temperatures, along with metabolic heat production calculated via indirect calorimetry, were measured throughout rewarming.
Results: One male participant was removed from analysis due to lack of sufficient cooling. Rectal temperature decreased in the remaining participants by ∼1.1-1.2°C to 36.1°C during the initial immersion phase. Over the 60 min of rewarming, rectal temperature changes were Δ0.0 ± 0.6°C in a sleeping bag, Δ+0.2 ± 0.3°C in Doctor Down, and Δ+0.2 ± 0.3°C in TYVAC, with no significant differences across methods. Mean skin temperatures, metabolic heat production, and perceptual measures were also similar across methods with no method×time interactions.
Conclusions: After 60 min of passive rewarming in cold conditions, all three rewarming methods were able to stall continued core cooling to levels at or slightly above post-immersion temperatures. With no differences in any physiological measures, it appears that all three rewarming methods are equally viable options for wilderness responders, and the choice should come down to environmetal conditions, availability, convenience, and ergonomics rather than rewarming efficacy.
期刊介绍:
Wilderness & Environmental Medicine, the official journal of the Wilderness Medical Society, is the leading journal for physicians practicing medicine in austere environments. This quarterly journal features articles on all aspects of wilderness medicine, including high altitude and climbing, cold- and heat-related phenomena, natural environmental disasters, immersion and near-drowning, diving, and barotrauma, hazardous plants/animals/insects/marine animals, animal attacks, search and rescue, ethical and legal issues, aeromedial transport, survival physiology, medicine in remote environments, travel medicine, operational medicine, and wilderness trauma management. It presents original research and clinical reports from scientists and practitioners around the globe. WEM invites submissions from authors who want to take advantage of our established publication''s unique scope, wide readership, and international recognition in the field of wilderness medicine. Its readership is a diverse group of medical and outdoor professionals who choose WEM as their primary wilderness medical resource.