Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
Ann Med. 2022 Dec;54(1):1118-1125. doi: 10.1080/07853890.2022.2067355.
Insulin is temperature sensitive as high temperatures reduce its potency. Refrigeration for insulin storage is still needed but households in remote areas do not have refrigerators. Also, the electricity supply is usually affected by natural disasters. We aim to examine the temperature-reducing efficacy of cooling devices in hot-humid conditions.
Five cooling devices, (1) earthen jar filled with water, (2) earthen jar filled with soil, (3) two clay pots, gap filled with wet soil, (4) two clay pots, gap filled with wet sand, and (5) commercial cooling wallet were used in this study. External and internal temperatures were monitored by the temperature logger between October 2019 and September 2020 in Narathiwat, Thailand. Cooling efficacy was assessed by average absolute temperature reduction and relative cooling effect.
Mean external temperature and humidity were 27.3 ± 1.5 °C and 78.2 ± 7.1%RH. The mean differences between the external and internal temperatures were; device (1) -0.1 ± 0.6 °C ( = NS), (2) 0.0 ± 0.8 °C ( = NS), (3) -1.7 ± 0.9 °C ( < .0001), (4) -2.0 ± 0.9 °C ( < .0001), and (5) -1.8 ± 0.9 °C ( < .0001). Device no. 3, 4, and 5 achieved a constant temperature reduction. The most efficacious device was device no. 4 with a relative cooling effect of 63.6% better than the cooling wallet (57.7%, = .003). All devices were more efficacious at lower humidity levels.
Traditional low-cost devices, such as clay pots, reduce storage temperatures to or close to room temperature in hot-humid climates. This study provides some guidance for insulin storage in hot-humid environments.
胰岛素对温度敏感，高温会降低其效力。尽管胰岛素仍需冷藏保存，但偏远地区的家庭没有冰箱。此外，供电通常会受到自然灾害的影响。我们旨在研究在湿热条件下冷却设备的降温效果。
本研究使用了 5 种冷却设备，（1）装满水的土罐，（2）装满土的土罐，（3）两个填有湿土的黏土锅，（4）两个填有湿沙的黏土锅，和（5）商用冷却钱包。2019 年 10 月至 2020 年 9 月期间，在泰国那拉提瓦使用温度记录仪监测外部和内部温度。通过平均绝对温度降低和相对冷却效果评估冷却效果。
外部平均温度和湿度分别为 27.3 ± 1.5°C 和 78.2 ± 7.1%RH。外部和内部温度之间的平均差异为；设备（1）-0.1 ± 0.6°C（无统计学差异，NS），（2）0.0 ± 0.8°C（无统计学差异，NS），（3）-1.7 ± 0.9°C（<.0001），（4）-2.0 ± 0.9°C（<.0001），和（5）-1.8 ± 0.9°C（<.0001）。设备 3、4 和 5 达到了恒定的温度降低。最有效的设备是设备 4，其相对冷却效果为 63.6%，优于冷却钱包（57.7%，<.003）。所有设备在较低湿度水平下的效果更好。
在湿热气候下，传统的低成本设备，如黏土锅，可以将储存温度降低至接近室温。本研究为胰岛素在湿热环境下的储存提供了一些指导。
