A nurse is caring for a client who is experiencing diabetic ketoacidosis (DKA). Which of the following is the priority intervention by the nurse?

Diabetic ketoacidosis (DKA) is an acute, life-threatening complication of diabetes mellitus characterized by hyperglycemia, ketosis, and metabolic acidosis due to insulin deficiency. It leads to severe dehydration from osmotic diuresis and electrolyte imbalances. Management follows a priority sequence focusing first on fluid resuscitation, then insulin therapy, and correction of electrolyte disturbances. Restoring circulating volume is essential to stabilize perfusion and support organ function. A. Initiating a continuous IV insulin infusion is essential in DKA management because insulin stops ketone production and lowers blood glucose. However, it is not the first priority because fluids must be replaced first to restore circulation and renal perfusion before insulin administration is fully effective. B. Bicarbonate infusion is rarely used in DKA and is reserved only for severe acidosis (typically pH < 6.9). Routine administration is not recommended because it can worsen hypokalemia and delay recovery. Therefore, it is not a priority intervention. C. Administration of 0.9% sodium chloride is the priority intervention because it rapidly restores intravascular volume depleted by osmotic diuresis. Fluid resuscitation improves tissue perfusion, supports blood pressure, and enhances renal clearance of glucose and ketones. This is the first step in stabilizing a client with DKA. D. Checking potassium levels is important in DKA because insulin therapy and acidosis correction can significantly shift potassium levels. However, this is an assessment action rather than an immediate treatment priority. Fluid replacement must occur first before electrolyte management and insulin therapy are initiated.