Journal of Applied Physiology, Vol 63, Issue 2 869-871, Copyright © 1987 by American Physiological Society
Detailed characterization of a tank used for head-out water immersion in humans
M. Epstein, P. Norsk, R. Loutzenhiser and P. Sonke
Nephrology Section, Veterans Administration Medical Center, Miami, Florida.
Water immersion has long been known to produce marked diuresis,
natriuresis, and kaliuresis and suppression of the renin-aldosterone
system. These effects are mediated primarily by an increase in central
blood volume. Immersion has therefore gained increased acceptance in human
physiology for the investigation of the effects of central volume expansion
on renal function and hormonal responsiveness without altering the
composition of the extracellular fluid. An immersion tank used for studies
in humans is described. Requisite features to ensure study reproducibility
include a constant temperature, capability to alter the depth of immersion
by adjusting water height, and the ability to maintain hygienic quality by
means of constant circulation of the water through a sand filter. A
constant temperature of 34.5 +/- 0.2 degrees C is maintained by
thermostatically controlling the heat exchange to a unidirectional
closed-circuit water system in the bottom of the immersion tank coursing
through a stream source. The level of the water may be adjusted to any
desired level by means of a waste line or an inlet of tap water.
