Electrolytes and pH Changes in Relation to Hypothermic Ventricular Fibrillation

Coronary arteriovenous electrolyte differences were studied in normo- and hypercapneic dogs at normal temperature and at 24 C. The ions measured were sodium, potassium, calcium, magnesium, chloride and hydrogen. Coronary arteriovenous electrolyte differences did not change during cooling in 16 dogs which did not suffer ventricular fibrillation. Ten hypercapneic hypothermia dogs exhibited characteristic Ca, K, and H ion changes at 24 C. before succumbing to ventricular fibrillation. The data suggest that ventricular fibrillation at low body temperatures is related to a gain of Ca and a loss of K and H ions by the hypothermia hypercapneic myocardium.