Acid-base disorders in hyperglycemia of insulin-dependent diabetic patients on chronic dialysis

The authors studied hyperglycemia occurring in insulin-dependent diabetic patients on chronic dialysis to determine the types of associated acid-base disorders, their treatment, and any differences from hyperglycemia in diabetic patients with intact renal function. Eighty-eight episodes of serum glucose greater than 25 mmol/L were observed, 23 in hemodialysis patients and 65 in patients on continuous peritoneal dialysis. Treatment consisted of low-dose insulin in 77 episodes and low-dose insulin plus saline in 11; no base was administered. Seventeen episodes (19%) presented with ketoacidosis. Arterial blood gas determinations were carried out at presentation in 37 of the episodes without ketoacidosis. Of these, 12 had respiratory alkalosis, six had respiratory acidosis and severe pulmonary edema, 14 had other single or mixed acid-base disorders, and only five had normal acid-base status. Insulin corrected the ketoacidosis in all instances and both pulmonary edema and respiratory acidosis in five of six instances. In eight cases metabolic alkalosis developed during treatment, without external acid loss. At the completion of treatment respiratory alkalosis was present in half the cases. No difference was noted between patients treated with hemodialysis or peritoneal dialysis. Insulin alone is sufficient for the management of hyperglycemia in dialysis patients. Certain acid-base disorders persist, but do not need further treatment. Hyperglycemia in patients on dialysis is characterized by infrequent development of metabolic acidosis and frequent presentation with respiratory alkalosis, by respiratory acidosis that is corrected by insulin, and by metabolic alkalosis developing during treatment without external cause.