Center for Exercise and Health?Fitness Research, Department of Health and Physical Activity, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA.
Prehosp Emerg Care. 2011 Apr-Jun;15(2):226-32. doi: 10.3109/10903127.2010.545482. Epub 2011 Feb 4.
We compared the use of two active cooling devices with passive cooling in a moderate-temperature (≈ 22 °C) environment on heart rate (HR) and core temperature (T(c)) recovery when applied to firefighters following 20 minutes of fire suppression.
Firefighters (23 men, two women) performed 20 minutes of fire suppression at a live-fire evolution. Immediately following the evolution, the subjects removed their thermal protective clothing and were randomized to receive forearm immersion (FI), ice water perfused cooling vest (CV), or passive (P) cooling in an air-conditioned medical trailer for 30 minutes. Heart rate and deep gastric temperature were monitored every 5 minutes during recovery.
A single 20-minute bout of fire suppression resulted in near-maximal mean ± standard deviation HR (175 ± 13 b min(-1), P; 172 ± 20 b·min(-1), FI; 177 ± 12 b·min(-1), CV) when compared with baseline (p < 0.001), a rapid and substantial rise in T(c) (38.2° ± 0.7°, P; 38.3° ± 0.4°, FI; 38.3° ± 0.3°, CV) compared with baseline (p < 0.001), and body mass lost from sweating of nearly 1 kilogram. Cooling rates (°C·min) differed (p = 0.036) by device, with FI (0.05 ± 0.04) providing higher rates than P (0.03 ± 0.02) or CV (0.03 ± 0.04), although differences over 30 minutes were small and recovery of body temperature was incomplete in all groups.
During 30 minutes of recovery following a 20-minute bout of fire suppression in a training academy setting, there is a slightly higher cooling rate for FI and no apparent benefit to CV when compared with P cooling in a moderate temperature environment.
我们比较了两种主动冷却装置与被动冷却在中等温度（约 22°C）环境下对消防员 20 分钟灭火后心率（HR）和核心温度（T(c)）恢复的影响。
消防员（23 男，2 女）在一次现场演练中进行了 20 分钟的灭火。演练结束后，受试者立即脱下热防护服，并随机接受前臂浸泡（FI）、冰水灌注冷却背心（CV）或在空调医疗拖车内进行被动（P）冷却 30 分钟。在恢复过程中，每 5 分钟监测一次心率和胃深部温度。
单次 20 分钟的灭火导致平均心率（HR）接近最大值（175±13 b·min(-1)，P；172±20 b·min(-1)，FI；177±12 b·min(-1)，CV）与基线相比（p<0.001），核心温度（T(c)）迅速显著升高（P：38.2°±0.7°；FI：38.3°±0.4°；CV：38.3°±0.3°）与基线相比（p<0.001），出汗导致体重减轻近 1 公斤。冷却速率（°C·min）因装置而异（p=0.036），FI（0.05±0.04）提供的速率高于 P（0.03±0.02）或 CV（0.03±0.04），尽管在 30 分钟内差异较小，且所有组的体温恢复均不完全。
在训练学院环境中灭火 20 分钟后 30 分钟的恢复期内，FI 的冷却速率略高，与 P 冷却相比，CV 无明显优势。
