Basic Conditions for CO₂ Vapour Bath / 日本温泉気候物理医学会雑誌

ABSTRACT

Tissue partial pressure of O₂ (PO₂) and CO₂ (PCO₂) in CO₂ vapour bath were measured on rabbit by means of Medical Mass Spectrometry, MEDSPECT II, Chemetron, U. S. A.<br>Topical absorption of CO₂ through the skin exposed to CO₂ gas was confirmed by comparing the subcutaneous tissue PO₂ and PCO₂ in CO₂ vapour bath with those of CO₂ free head area; subcutaneous tissue PO₂ and PCO₂ were elevated by 92% and 48% respectively in the former, whereas subcutaneous tissue PO₂ and PCO₂ in the latter were found no change. Lowering of subcutaneous pH was found simultaneously with the elevation of PCO₂ in CO₂ vapour bath, contributing largely to the elevation of PO₂ in response to CO₂ accumulation.<br>Subcutaneous tissue PCO₂ reaches a saturated level in about 30 minutes regardless of each CO₂ flow rate varying from 1 to 5 liters per minute. Too much application of CO₂ gas is not always so effective as expected. Changes of PCO₂ and PO₂ were not in proportion to a rise in temperature from 33.4°C to 41.5°C on the same rabbit. It is, therefore, suggested that the optimal application of CO₂ gas on rabbits is at their indifferent temperature of around 37°C.<br>The optimal conditions for rabbits would be suggested as 1 liter of CO₂ gas per minute at 37°C for 30 minutes in consideration of the side effects on both circulatory and respiratory systems.<br>Based on the experimental data, conditions of 30 liters per minute at 40°C for 30 minutes would be recommended in clinical application of CO₂ gas cabin.