This sweat fails to evaporate and thus does not contribute to body cooling. The secretory pressure of sweat glands allows sweat to flow outward to dissolve in the water. Sweating, however, also occurs under water.
Stem cell treatment for near drowning skin#
In HWI, the high humidity of the ambient air around a hot tub, with only the head and neck skin above the water, allows limited evaporation of sweat above the water. The phase-change from a liquid to a gaseous state removes heat from the skin and cools the body. In ambient air, elimination of body heat occurs mainly by sweat evaporation. Thermoregulation during HWI differs from thermoregulation in hot ambient air. The high incidence of Japanese hot-water tub fatalities suggests that HWI may lead to drowning ( 2, 109, 175, 191, 211, 291). People may sit and soak up to the shoulders or neck in deep hot (38-43☌) tubs for 5–15 min ( 96, 118). It is believed that healthy persons may benefit from the physiological effects of hot-water immersion (HWI) on the body's homeostatic systems ( 16, 25, 48, 53, 81, 118). Ofuro bathing is a component of Japan's national culture and identity. Some drownings, however, occur in hot-water tubs, while pouring hot water over the head, or during diving or competitive swimming in warm water. Most drowning events occur at water temperatures below the point of thermoneutrality, which is 35☌ ± 0.5. “Thermoneutral” is the term for the water temperature at which heat loss equals heat production ( 53, 238).
The objective of the review is to summarize the physiological mechanisms associated with drowning and to explore whether future physiological studies may contribute to the prevention, treatment, and forensic investigations of drowning. Since human drowning mechanisms per se are difficult to study, observations from animal experiments, case series, and forensics have been included where helpful.
The present work provides an overview of the current understanding of the physiological mechanisms that may occur during a submersion or immersion incident. Although there are clinical differences between submersion and immersion ( 30, 275), the details of the physiological processes have not been reviewed. The exact physiological mechanisms of this process are complex and largely unknown, and have only been speculatively described in drowning reviews and studies over recent decades ( 29, 108, 132, 195, 257). Furthermore, drowning as a result of flooding, ferryboat accidents, and accidents with boat-carrying refugees and migrants are not reported in the standard drowning statistics ( 140, 164).ĭrowning is formally defined as the process of experiencing respiratory impairment from submersion/immersion in liquid ( 273).
Low- and middle-income countries, where most drownings occur, have incomplete recording of drowning events. Although standard WHO statistics report almost 375,000 persons drowning each year, the actual figure for world-wide drowning is probably four or five times as high. A recent report of the World Health Organization (WHO) labels drowning as one of the world's leading causes of death ( 164).
0 kommentar(er)
