Tan Pearl M S, Teo Eunice Y N, Ali Noreffendy B, Ang Bryan C H, Iskandar Iswady, Law Lydia Y L, Lee Jason K W
Combat Protection and Performance, Defence Medical and Environmental Research Institute, Singapore.
Soldier Performance Centre, Singapore Armed Forces.
J Athl Train. 2017 Feb;52(2):108-116. doi: 10.4085/1062-6050-52.1.11. Epub 2017 Feb 3.
Rapid diagnosis and expeditious cooling of individuals with exertional heat stroke is paramount for survival.
To evaluate the efficacy of various cooling systems after exercise-induced hyperthermia.
Crossover study.
Laboratory.
Twenty-two men (age = 24 ± 2 years, height = 1.76 ± 0.07 m, mass = 70.7 ± 9.5 kg) participated.
INTERVENTION(S): Each participant completed a treadmill walk until body core temperature reached 39.50°C. The treadmill walk was performed at 5.3 km/h on an 8.5% incline for 50 minutes and then at 5.0 km/h until the end of exercise. Each participant experienced 4 cooling phases in a randomized, repeated-crossover design: (1) no cooling (CON), (2) body-cooling unit (BCU), (3) EMCOOLS Flex.Pad (EC), and (4) ThermoSuit (TS). Cooling continued for 30 minutes or until body core temperature reached 38.00°C, whichever occurred earlier.
MAIN OUTCOME MEASURE(S): Body core temperature (obtained via an ingestible telemetric temperature sensor) and heart rate were measured continuously during the exercise and cooling phases. Rating of perceived exertion was monitored every 5 minutes during the exercise phase and thermal sensation every minute during the cooling phase.
The absolute cooling rate was greatest with TS (0.16°C/min ± 0.06°C/min) followed by EC (0.12°C/min ± 0.04°C/min), BCU (0.09°C/min ± 0.06°C/min), and CON (0.06°C/min ± 0.02°C/min; P < .001). The TS offered a greater cooling rate than all other cooling modalities in this study, whereas EC offered a greater cooling rate than both CON and BCU (P < .0083 for all). Effect-size calculations, however, showed that EC and BCU were not clinically different.
These findings provide objective evidence for selecting the most effective cooling system of those we evaluated for cooling individuals with exercise-induced hyperthermia. Nevertheless, factors other than cooling efficacy need to be considered when selecting an appropriate cooling system.
对劳力性热射病患者进行快速诊断和及时降温对其生存至关重要。
评估运动诱发体温过高后各种降温系统的效果。
交叉研究。
实验室。
22名男性（年龄=24±2岁，身高=1.76±0.07米，体重=70.7±9.5千克）参与。
每位参与者在跑步机上行走，直至体核温度达到39.50°C。跑步机行走以5.3千米/小时的速度在8.5%的坡度上进行50分钟，然后以5.0千米/小时的速度持续至运动结束。每位参与者在随机、重复交叉设计中经历4个降温阶段：（1）不降温（CON），（2）身体降温单元（BCU），（3）EMCOOLS Flex.Pad（EC），以及（4）ThermoSuit（TS）。降温持续30分钟或直至体核温度达到38.00°C，以先达到者为准。
在运动和降温阶段持续测量体核温度（通过可摄入式遥测温度传感器获取）和心率。在运动阶段每5分钟监测一次主观用力程度，在降温阶段每分钟监测一次热感觉。
TS的绝对降温速率最大（0.16°C/分钟±0.06°C/分钟），其次是EC（0.12°C/分钟±0.04°C/分钟）、BCU（0.09°C/分钟±0.06°C/分钟）和CON（0.06°C/分钟±0.02°C/分钟；P<.001）。在本研究中，TS的降温速率高于所有其他降温方式，而EC的降温速率高于CON和BCU两者（所有比较P<.0083）。然而，效应量计算表明，EC和BCU在临床上并无差异。
这些发现为从我们评估的用于运动诱发体温过高患者降温的系统中选择最有效的降温系统提供了客观证据。尽管如此，在选择合适的降温系统时，还需要考虑降温效果以外的因素。
