Evaluation of cutaneous insensible water loss during hyperbaric exposure in humans.
BACKGROUND
Water evaporation diminishes in high pressure environment, however it is unknown whether insensible water dissipation from the human skin falls as a function of the increased environmental pressure. We designed the present study to measure cutaneous insensible water loss at various pressures during exposure to a simulated saturation dive.


METHODS
Four healthy male volunteers were exposed to eight different pressures between 1 and 18.4 atmospheres absolute (atm abs). Resting insensible water loss from the skin was measured as change in the body weight and corrected for the weight of the respiratory CO2 - O2 gas exchange and the respiratory water dissipation.


RESULTS
We made an equation for the relationship between cutaneous insensible water loss and environmental pressure as: w = 14.5 X p(-0.48), where, w is cutaneous insensible water loss in g x m(-2) x h(-1), and P is the environmental pressure in atm abs. The average cutaneous insensible water loss (15.3 g x m(-2) x h(-1)) at normal atmosphere decreased (p < 0.01) to 4.2 g x m(-2) x h(-1) (reduced by 73%) during a saturation dive to 18.4 atm abs.


CONCLUSIONS
The amount of insensible water loss estimated from the equation was comparable to that of reported observations.
Yamaguchi
H
H
Marine Ecosystems and Environment Research Department, Japan Marine Science and Technology Center, Yokosuka. yamaguchih@jamstec.go.jp
Mohri
M
M
Shiraki
K
K
D000328:Adult; D001274:Atmospheric Pressure; D001833:Body Temperature Regulation / Q000502:physiology; D001835:Body Weight; D001944:Breath Tests; D002245:Carbon Dioxide / Q000032:analysis; D004242:Diving / Q000009:adverse effects / Q000502:physiology*; D006801:Humans; D008297:Male; D010100:Oxygen / Q000032:analysis; D010101:Oxygen Consumption / Q000502:physiology; D011659:Pulmonary Gas Exchange / Q000502:physiology; D012123:Pulmonary Ventilation / Q000502:physiology; D012879:Skin Physiological Phenomena; D014870:Water Loss, Insensible / Q000502:physiology*; D014882:Water-Electrolyte Balance / Q000502:physiology
D002245:Carbon Dioxide; D010100:Oxygen