Practical management of diabetic ketoacidosis and hyperosmolar coma

Abstract

In diabetic ketoacidosis (DKA) and particularly in hyperosmolar coma, rapid normalisation of the measured extracellular fluid abnormalities cannot be equated with optimal management. In both disorders there are complex imbalances between extra- and intracellular compartments that are best corrected in a series of rational steps, based on an understanding of pathophysiology. Fluid administration in DKA can generally be divided into three successive phases: (i) a short period of rapid isotonic saline infusion, (ii) slower infusion of isotonic saline with potassium chloride, and (iii) glucose-potassium infusion until oral food intake is well established. In severe cases, there is a definite place for judicious use of isotonic sodium bicarbonate in small amounts. While insulin infusion is desirable, intramuscular insulin remains a satisfactory alternative. Biochemical monitoring is mandatory and management must be reviewed and modified every three to four hours on the basis of the clinical and biochemical response. In the management of hyperosmolar coma, insulin and fluid therapy are more conservative, with the aim of achieving complete rehydration and normoglycaemia only after 36 to 72 hours. Pulmonary complications and the effects of tissue ischaemia, as well as thromboembolic events, remain important causes of death in both disorders. The frequent recurrences of DKA that occur in a group of psychiatrically-unstable young patients remain an unsolved problem.