Running cold tap water over accidental burns and scalds is generally accepted as the best way to cool the skin and prevent blistering.
But a study in the Journal of Plastic, Reconstructive & Aesthetic Surgery suggests the reverse—that using warm instead of cold water, while counterintuitive, may be a more effective method of limiting tissue damage and restoring blood flow to burned areas.
Swiss researchers used a heated metal template to induce same-size burns on anesthetized rats in four places on each of their backs. (Pain medication was administered before and after the procedure).
One group of rats was treated for 20 minutes with gauze soaked in water cooled to 62.6 degrees Fahrenheit. A second group received gauze containing water at 98.6 degrees.
A third group of control rats wasn't treated. The burns and unburned spaces between the burns were tested after one hour, 24 hours, four days and seven days.
Within 24 hours, burn damage in the control rats had extended to underlying tissues, whereas the burned area didn't immediately change in the rats treated with cold or warm water, researchers said. After four days, all the animals developed tissue damage, or necrosis, in the spaces between the burns, but the damage was significantly less in the rats treated with warm water.
Although the experiments were performed on rats, the researchers said the basic principles and mechanisms of burn progression are similar to those in humans.
While applying cold tap water to burns helps to cool the skin, it can be painful after 20 minutes and leads to abnormally low temperature in the skin, according to lead researcher Reto Wettstein, a plastic and reconstructive hand surgeon in Basel, Switzerland.
Wettstein personally practices rapid cooling with cold water for about a minute and then switches to warm water to help restore circulation.