In diabetic ketoacidosis, patients are at risk for which electrolyte disturbance during treatment?

• A. Hyperkalemia
• B. Hypercalcemia
• C. Hypokalemia
• D. Hypermagnesemia

Answer: (C)

In treating diabetic ketoacidosis, the key issue is that insulin therapy and correction of acidosis drive potassium from the extracellular space into cells, uncovering a true potassium deficit. Before treatment, potassium may appear normal or high because of insulin deficiency and acidosis, but total body potassium is actually depleted due to urinary and GI losses. As insulin is given and the patient’s fluids and glucose improve, potassium shifts intracellularly and ongoing renal losses continue, so the serum potassium can fall rapidly, causing hypokalemia. This makes hypokalemia the main electrolyte disturbance to anticipate during treatment. Monitoring potassium closely and replacing it according to protocols is essential, for example, holding insulin if potassium is very low and ensuring adequate supplementation when levels are in the safe range. Hyperkalemia is more of a concern before treatment rather than during, and hypercalcemia or hypermagnesemia are not the hallmark disturbances associated with the treatment phase.