Lan Chen,1,* Dingping Jin,1,* Zhumei Gong,2 Liyun Lu,3 Junlu Zhao,4 Shuying Xu,5 Xiaoling Yang,6 Yuping Zhang,1 Xiuqin Feng1 

1Nursing Department, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People’s Republic of China; 2Emergency Department, Yiwu Central Hospital, Yiwu, Zhejiang Province, People’s Republic of China; 3Emergency Department, Jinhua People’s Hospital, Jinhua, Zhejiang Province, People’s Republic of China; 4Emergency Department, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua Municipal Central Hospital, Jinhua, Zhejiang Province, People’s Republic of China; 5Emergency Department, Dongyang People’s Hospital, Dongyang, Zhejiang Province, People’s Republic of China; 6Emergency Department, Lanxi People’s Hospital, Lanxi, Zhejiang Province, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Xiuqin Feng, Nursing Department, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People’s Republic of China, Email fengxiuqin@zju.edu.cn

Objective: Water circulation cooling blankets are commonly used in heat stroke management, but their efficacy and safety remain insufficiently studied. This study aimed to assess the cooling effect of the cooling blanket within the first 24 hours after emergency department admission in patients with heat stroke.
Methods: Retrospective data were collected from six hospitals. The primary outcomes included body temperature at 0.5 and 2 hours post-treatment and changes in temperature during these intervals. The cooling effect was assessed using logistic regression, generalized additive mixed models, and genetic and propensity score matching. Test effectiveness was evaluated based on the non-inferiority test formula.
Results: A total of 191 patients were included, with 84 (44.0%) receiving cooling with the blanket. The mean cooling duration was 2 hours. Body temperatures at 0.5 hours were 39.80 ± 0.96 °C in the cooling blanket group versus 39.26 ± 0.94 °C in the non-cooling blanket group. At 2 hours, temperatures were 38.08 ± 1.00 °C and 37.84 ± 0.96 °C, respectively. No significant differences were found in body temperature at 0.5 hours (β, − 0.19 [95% CI, − 0.50, 0.12]; P = 0.242) or 2 hours (β, − 0.24 [95% CI, − 0.57, 0.09]; P = 0.161) between the cooling blanket and non-cooling blanket groups. Similarly, no significant differences in temperature changes at 0.5 or 2 hours were observed. After adjusting for propensity scores, no differences in temperature were found in the matching cohort. The non-inferiority criterion was met, with effectiveness scores of 1.000 at 0.5 hours and 0.998 at 2 hours.
Conclusion: The cooling blanket demonstrated no significant temperature reduction advantage compared to the non-cooling blanket group. High-quality randomized controlled trials remain necessary to further evaluate its therapeutic role in heat stroke management.

Keywords: cooling blanket, cooling effect, heat stroke, generalised additive mixed model, genetic matching