Experimental studies on the effect of potassium citrate for elective cardiac arrest and a trial of the concomitant use of glucose and insulin.

Abstract

The isolated Langendorf dog's heart preparation with cross circulation was arranged for studying the effect of anoxia by coronary occlusion and cardiac arrest by drugs, potassium citrate, potassium bicarbonate, and potassium chloride with or without 500mg. of glucose and 10 units of insulin. The heart rate, coronary blood flow, myocardial oxygen consumption and histological changes were studied.(1) The more severe and profuse histological changes, mainly irreversible myocardial degeneration, were produced when potassium citrate was used than those produced by 30 minutes coronary occlusion.(2) The effect of anoxia, i.e., the prominent reactive hyperemia, the sustained increase of the coronary flow and the oxygen consumption and the increase of heart rate observed by the 30 minutes coronary occlusion were definitely restricted by the use of potassium citrate. The concomitant use of the glucose with insulin alleviated the toxic effect of citrate to some extent.(3) The alkalization in order to avoid the metabolic acidosis of the heart muscle occurring during cardiac arrest left a long lasting tachycardia and thus produced an increase of myocardial oxygen consumption for a period of observation.