Electrocardiogram as a Guide to Potassium Replacement in Diabetic Ketoacidosis

Twenty-three patients in severe diabetic ketoacidosis were followed by continuous electrocardiographic monitoring using Lead II of the electrocardiogram throughout their course of treatment. Frequent serum potassium determinations were carried out and correlated with the ECG changes. On admission to hospital the electrocardiogram of ketoacidotic patients showed varied T wave patterns often with little correlation to the serum potassium, but the two patients who were initially hypokalemic were identified from the ECG appearances. Following the infusion of fluids alone the serum potassium fell with accompanying T wave and ST segment changes while the administration of potassium reversed these abnormalities. Although the electrocardiogram is not a substitute for serum potassium determinations, it is a useful guide to potassium replacement in diabetic ketoacidosis. In the successful management of this diabetic emergency the achievement and maintenance of a normal ECG, by means of early and continuous administration of potassium in the infused fluids, should be an important objective of treatment.