Change of digital blood flow during sodium sulfate bathing was studied using laser Doppler flowmeter. The 10 subjects were divided into two groups; group A and group B. In group A, digital bloood flow was measured in the following order; in the air→plain water→air→sodium sulfate bathing→air, while in group B, in the air→sodium sulfate bathing→air→plain water→air. The temperature of the water was kept at 40°C using thermostat. The 10g of sodium sulfate was dissolved in the 10L of water. In group A, the digital blood flow was 60.2±16.7 in the plain water and 70.6±35.0 in the sodium sulfate water, while in group B, 30.4±12.7 in the sodium sulfate water and 7.36±10.06 in the plain water (P<0.05).
Above results suggest an increase in digital blood flow in the sodium sulfate bathing, although there were great differences by individual and by the order of immersion.

The purpose of this study was to clarify the effect of warm water bathing (40°C) of the hand on the psychologic sweating measured in the opposite palm. The subjects were 2 males and 4 females, aged 38±10 years (26-58 years). The psychologic sweating was estimated by the apparatus developed by Sakaguchi et al (Sakaguchi, M. et al BME 26: 213, 1988). The room temperature was 27 to 28°C and the relative humidity was 60 to 70%. The sensor was attached using adhesive tape on the right palm. Then the psychologic sweating was measured after deep respiration, mental arithmetic, hand grip, bathing in warm water of 40°C at the level of left wrist. The results showed that the mean values of palmar sweating were 15.6 for deep respiration, 16.8 for mental arithmetic, 15.5 for hand grip and 0 for warm water bathing.
Above results suggest that local water bathing of moderate temperature induces a decrease of psychologic sweating, probably due to relaxing effect of the cerebrum.