Running water as first aid for burn and early hypothermia: A numerical investigation on human skin

The cooling rate of the running water on the burn wound depends on both physiological and water parameters. Prolonged use of cold water on the burn wound may cause hypothermia. We aimed to investigate the running water as first aid for burns and find out the cooling effect of bio-heat transfer to avoid hypothermia. Measuring the temperature variation across the tissue layers is the main limitation of working with in vivo experiments and a one-dimensional model. Moreover, multiple boundary conditions cannot be used in one-dimensional models. These limitations motivate us to develop ADVENTURE Thermal to perform a finite element analysis of the bio-heat equation in the 3D skin model for the burn analysis. A circular wound was developed on a 3-layered skin with a hot disk of 92 °C for 15 s. Then the wound area was cooled with the running water, which had different parameters. Running water at 15 °C takes 20–30 % less time than being immersed in water at the same temperature. Results reveal that cooling rates of burns significantly depend on the temperature and heat transfer coefficient of the water. To avoid hypothermia, the use of the running water with a heat transfer coefficient ranging from 800 to 1000 W/m² °C (flow rate around 1.6 L/min) and temperature ranging from 15 to 20 °C for not more than 10 min is recommended. In the end, the running water cools the tissue with a small blood perfusion rate faster. The results agree with the experiment.