EXPERIMENTAL AND CLINICAL STUDIES ON ADRENOCORTICAL FUNCTION IN EXTRACORPOREAL CIRCULATION

Abstract

1. Experimental StudiesNineteen mongrel dogs were used to study the arterial pressure, adrenal venous blood flow, concentration of free 17-OHCS in adrenal venous plasma, secretion of free 17-OHCS in adrenal venous plasma and concentration of free 17-OHCS in peripheral venous plasma in the purpose of exploring the variation of adrenocortical function experimentally.1) Average of adrenal venous blood flow is 6.56 cc/min, and that of 17-OHCS concentration in adrenal-venous-plasma is 197.1 μg/dl before extracorporeal circulation. Secretion of 17-OHCS is 6.25μg/min and the concenraition in peripheral venous plasma is 12.2μg/dl.2) Relationship between arterial blood pressure and adrenal venous blood flow in different kinds of extracorporeal circulation is parallel, when they are observed in normo-and hypothermal perfusion groups.3) Adrenal venous blood flow in normothermal group is inversely proportional to 17-OHCS concentration in adrenal venous plasma, but not in hypothermal group.4) As to secretion of 17-OHCS in adrenal venous plasma, the normothermal group shows the increase of secretion, while hypothermal group shows the decrease which seems to be resulted from the functional inhibition of adrenal cortex.5) Secretion of adrenal gland is directly proportional to 17-OHCS concentration in the peripheral venous plsma.6) Adrenal tissue does not show any remarkable histological changes after perfusion.2.Clinical StudiesAdrenocortical functions of 13 clinical cases in normo-and hypothermal extracorporeal circulation were investigated by estimating of free-17-OHCS concentration in peripheral venous plasma and excretion of 17-OHCS and 17-KS in urine.1) Arterial blood pressure in cold perfusion under 35°C sustains almost constancy, 60mm Hg., while that in warm perfusion shows higher values.2) Though 17-OHCS concentration in plasma during the perfusion decreases markedly in hypothermal group and increase again by warming, hypothermal group shows nothing changeable. Both normo-and hypothermal group show the same postoperative variation curve. Concentration becomes highest 3-6 hours after the operation, then it gradually decrease, and comes back to normal value after 5 days.3) No remarkable difference can be found in 17-OHCS concentration in plasma between Z-uhdi and Kay-cross typed artificial oxygenator.4) Excretion of urinary 17-OHCS has an almost parallel relationship to the postoperative variation of 17 OHCS concentration in plasma. The excretion becomes maxmal in the following day of operation and recovers to normal on the fifth day.5) When excretion of urinary 17-OHCS is observed from viewpoint of perfused volume, low perfused group shows higher excretory value than that in high perfused group. We could not obtain any experimental and clinical evaluation to suggest the adrenal insufficiency.