Which electrolyte abnormality is anticipated after starting insulin infusion in this hyperglycemic patient?

Which electrolyte abnormality is anticipated after starting insulin infusion in this hyperglycemic patient?

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

Answer: (B)

Insulin infusion in a hyperglycemic patient pushes potassium from the blood into body cells, increasing the activity of the Na+/K+-ATPase pump. This causes a drop in extracellular (serum) potassium, making hypokalemia the expected electrolyte change after starting insulin. Even though total body potassium is often depleted from diuresis and lack of insulin, the immediate effect of insulin is to shift potassium into cells, which can unmask or worsen low potassium if not monitored and replaced as needed. Hyperkalemia is unlikely once insulin is started because the hormone promotes potassium entry into cells. Hypercalcemia isn’t a direct consequence of insulin therapy in this scenario, and hyponatremia may be present with hyperglycemia itself but isn’t the rapid shift caused by insulin infusion.

Insulin infusion in a hyperglycemic patient pushes potassium from the blood into body cells, increasing the activity of the Na+/K+-ATPase pump. This causes a drop in extracellular (serum) potassium, making hypokalemia the expected electrolyte change after starting insulin. Even though total body potassium is often depleted from diuresis and lack of insulin, the immediate effect of insulin is to shift potassium into cells, which can unmask or worsen low potassium if not monitored and replaced as needed. Hyperkalemia is unlikely once insulin is started because the hormone promotes potassium entry into cells. Hypercalcemia isn’t a direct consequence of insulin therapy in this scenario, and hyponatremia may be present with hyperglycemia itself but isn’t the rapid shift caused by insulin infusion.