RESUMEN
Actual changes in tissue partial pressures of each gas and tissue perfusion with serial artificial CO<sub>2</sub> bathing were evaluated by means of medical mass spectrometry using 5 rabbits.<br>An artificial CO<sub>2</sub> bath was prepared by adding “BUB”-KAO, a 50g sodium hydrogencarbonate and succinic acid tablet producing fine CO<sub>2</sub> bubbles in water of constant temperature 20-litre tub at 36-37°C.<br>Regional tissue perfusion volume was determined on the basis of a clearance curve for Argon tissue partial pressure which was monitored by an on-line computer system with mass spectrometry.<br>Increase in subcutaneous tissue PCO<sub>2</sub> changed from 27% to 10%, and in PO<sub>2</sub> from 12% to 5% on average by serial bathing every day for 4 weeks, on the other hand tissue perfusion volume was increased in 3 out of 5 cases; from 20.85±3.56 (X±SE) m<i>l</i>/100g/min, SD=6.71, p<0.05 to 25.23±8.00 (X±SE) m<i>l</i>/100g/min, SD=6.96, p<0.05.<br>CO<sub>2</sub> has been shown to be locally absorbed through the skin resulting in the elevation of subcutaneous tissue CO<sub>2</sub> partial pessure which decreases depending on the tissue perfusion irrespective of metabolic processes. It is, therefore, assumed that the elimination of absorbed constituents by serial bathings is not caused by a decrease in the percutaneous absorption rate but an increase in washing out rate by the improved tissue perfusion.