How does insulin therapy affect potassium distribution, and what monitoring should accompany DKA treatment?

• A. Insulin drives potassium into cells; risk of hypokalemia; monitor potassium and ECG.
• B. Insulin raises potassium; monitor calcium.
• C. Insulin has no effect on potassium.
• D. Insulin causes hyperkalemia.

Answer: (A)

Insulin therapy drives potassium into cells by stimulating the Na+/K+-ATPase pump, so starting insulin in DKA can cause the serum potassium to fall even though total body potassium is actually depleted from diuresis and losses. That initial hyperkalemia or normal potassium seen in DKA often masks a depleted total body potassium; as insulin is given and acidosis resolves, potassium shifts back into cells, which can lead to rapid hypokalemia and potentially dangerous arrhythmias. Because of this, monitoring potassium levels frequently during treatment is essential, and ECG monitoring helps detect rhythm disturbances as potassium moves with therapy. Potassium replacement is guided by the current potassium level so you can continue insulin safely while preventing hypokalemia. This combination—watching potassium closely and tracking the ECG—is key during DKA management.