背景:在冷应激或低体温患者的院前护理中使用蒸汽屏障旨在减少蒸发热损失并加速复温。在各种指南中建议使用蒸汽屏障,以及绝缘和防风/防水层以及主动的外部加温装置;但是,其效果的证据是有限的。这项研究旨在研究在推荐的“卷饼”模型中使用蒸汽屏障作为内层的效果,以在现场包裹低温患者。
方法:在此,随机化,交叉现场研究,16名穿着湿衣服的健康志愿者在雪室中接受30分钟的冷却期,然后将其包裹在模型中,该模型包括具有(干预)或不具有(控制)蒸汽屏障的主动加热源。平均皮肤温度,核心温度,测量了模型中的湿度,使用主观问卷评估寒战强度和热舒适性。平均皮肤温度是主要结果,而湿度和热舒适是次要结局.主要结果数据采用协方差分析(ANCOVA)进行分析。
结果:我们发现约25分钟后,干预组的平均皮肤温度高于对照组(p<0.05),而这一差异在60分钟的研究中持续存在.60分钟后,平均皮肤温度的最大差异为0.93°C。5分钟后,对照组的蒸汽屏障外湿度水平显着高于干预组。主观舒适度无显著差异。然而,与对照组相比,干预组的舒适度增加趋势一致.
结论:使用蒸汽屏障作为最内层,与主动外部热源结合使用,会导致穿着湿衣服且有意外低体温风险的患者的平均皮肤复温率更高。
背景:ClinicalTrials.gov标识符:NCT05779722。
BACKGROUND: Use of a vapor barrier in the prehospital care of cold-stressed or hypothermic patients aims to reduce evaporative heat loss and accelerate rewarming. The application of a vapor barrier is recommended in various guidelines, along with both insulating and wind/waterproof layers and an active external rewarming device; however, evidence of its effect is limited. This study aimed to investigate the effect of using a vapor barrier as the inner layer in the recommended \"burrito\" model for wrapping hypothermic patients in the field.
METHODS: In this, randomized, crossover field study, 16 healthy volunteers wearing wet clothing were subjected to a 30-minute cooling period in a snow chamber before being wrapped in a model including an active heating source either with (intervention) or without (control) a vapor barrier. The mean skin temperature, core temperature, and humidity in the model were measured, and the shivering intensity and thermal comfort were assessed using a subjective questionnaire. The mean skin temperature was the primary outcome, whereas humidity and thermal comfort were the secondary outcomes. Primary outcome data were analyzed using analysis of covariance (ANCOVA).
RESULTS: We found a higher mean skin temperature in the intervention group than in the control group after approximately 25 min (p < 0.05), and this difference persisted for the rest of the 60-minute study period. The largest difference in mean skin temperature was 0.93 °C after 60 min. Humidity levels outside the vapor barrier were significantly higher in the control group than in the intervention group after 5 min. There were no significant differences in subjective comfort. However, there was a consistent trend toward increased comfort in the intervention group compared with the control group.
CONCLUSIONS: The use of a vapor barrier as the innermost layer in combination with an active external heat source leads to higher mean skin rewarming rates in patients wearing wet clothing who are at risk of accidental hypothermia.
BACKGROUND: ClinicalTrials.gov identifier: NCT05779722.