A 22-year-old man with a history of type 1 diabetes mellitus is brought to the emergency department due to confusion, intractable vomiting, and diffuse abdominal pain. He reports missing his insulin doses for the past two days due to a gastrointestinal illness. His blood pressure is 90/60 mmHg, heart rate is 125/min, and respiratory rate is 28/min with deep, rapid breaths. Mucous membranes are extremely dry. Laboratory evaluation reveals a blood glucose of 580 mg/dL, an arterial pH of 7.15, serum bicarbonate of 12 mEq/L, an anion gap of 22 mEq/L, and a serum potassium of 4.8 mEq/L.
Arrange the following management steps in the correct chronological sequence for treating this patient's condition, from immediate resuscitation to resolution.
- 1Administer rapid intravenous fluid resuscitation with 0.9% normal saline
- 2Initiate a continuous intravenous regular insulin infusion
- 3Add 5% dextrose to the intravenous maintenance fluids
- 4Transition to a subcutaneous basal-bolus insulin regimen
Answer
The correct chronological sequence for managing diabetic ketoacidosis is: 1) Administer rapid intravenous fluid resuscitation with 0.9% normal saline, 2) Initiate a continuous intravenous regular insulin infusion, 3) Add 5% dextrose to the intravenous maintenance fluids, and 4) Transition to a subcutaneous basal-bolus insulin regimen.
The established protocol for DKA management follows a strict physiological rationale: 1) restore volume with isotonic fluids to reverse shock; 2) stop ketogenesis with IV insulin (after ensuring K+ is ≥ 3.3 mEq/L); 3) prevent hypoglycemia by adding dextrose once glucose drops below 200 mg/dL to allow continued insulin therapy for ketone clearance; and 4) overlap and transition to subcutaneous insulin only after the anion gap is closed and the patient is eating.
Step-by-Step Solution
Key Concept
Diabetic Ketoacidosis (DKA) Stepwise Management