A 22-year-old man with type 1 diabetes mellitus is brought to the emergency department with abdominal pain, vomiting, and deep, rapid breathing. Laboratory studies confirm severe diabetic ketoacidosis (DKA) with a blood glucose of 540 mg/dL and a serum potassium of 4.8 mEq/L. Arrange the following management steps in the most appropriate chronological sequence.
- 1Administer an initial rapid intravenous bolus of 0.9% normal saline
- 2Initiate a continuous intravenous regular insulin infusion
- 3Add 5% dextrose to the intravenous fluids
- 4Transition to a subcutaneous basal-bolus insulin regimen
Answer
The correct sequence of DKA management is: 1) IV normal saline bolus, 2) IV regular insulin infusion, 3) Addition of 5% dextrose to IV fluids, and 4) Transition to subcutaneous insulin.
The standard sequence for DKA management begins with aggressive volume expansion using 0.9% normal saline to correct severe dehydration caused by osmotic diuresis. After confirming that serum potassium is >3.3 mEq/L, a continuous IV regular insulin infusion is started to halt lipolysis and ketogenesis. As the blood glucose level falls to around 200-250 mg/dL, 5% dextrose is added to the maintenance IV fluids; this prevents hypoglycemia while allowing the insulin infusion to continue until the anion gap closes. Finally, once the anion gap has normalized, acidosis has resolved, and the patient can tolerate oral intake, the patient is transitioned to subcutaneous insulin, and the IV insulin is discontinued shortly thereafter.
Step-by-Step Solution
Key Concept
The chronological management of diabetic ketoacidosis prioritizes fluid resuscitation, followed by insulin therapy, dextrose supplementation when glucose falls, and transition to subcutaneous insulin upon resolution.