|
Affiliation
|
Extremes Research Group, School of Sport, Health and Exercise Sciences, Bangor University, Bangor, United Kingdom. |
|
Abstract
|
OBJECTIVE: To compare the effectiveness of a single-layered polyethylene survival bag (P), a single-layered polyethylene survival bag with a hot drink (P+HD), a multi-layered metalized plastic sheeting survival bag (MPS: Blizzard Survival), and a multi-layered MPS survival bag with 4 large chemical heat pads (MPS+HP: Blizzard Heat) to treat cold casualties.
METHODS: Portable cold casualty treatment methods were compared by examining core and skin temperature, metabolic heat production, and thermal comfort during a 3-hour, 0°C cold air exposure in 7 shivering, near-hypothermic men (35.4°C). The hot drink (70°C, ~400ml, ~28kJ) was consumed at 0, 1, and 2 hours during the cold air exposure.
RESULTS: During the cold air exposure, core rewarming and thermal comfort were similar on all trials (P =.45 and P =.36, respectively). However, skin temperature was higher (10%-13%; P <.001; large effect sizes d > 2.7) and metabolic heat production lower (15%-39%; P <.05; large effect sizes d >.9) on MPS and MPS+HP than P and P+HD. The addition of heat pads further lowered metabolic heat production by 15% (MPS+HP vs MPS; P =.05; large effect size d =.9). The addition of the hot drink to polyethylene survival bag did not increase skin temperature or lower metabolic heat production.
CONCLUSIONS: Near-hypothermic cold casualties are rewarmed with less peripheral cold stress and shivering thermogenesis using a multi-layered MPS survival bag compared with a polyethylene survival bag. Prehospital rewarming is further aided by large chemical heat pads but not by hot drinks.
Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.
Language: en |