Which criterion best describes when to transition from IV insulin to subcutaneous insulin in DKA management?

• A. Transition when the patient tolerates oral intake and blood glucose approaches goal, with overlap of IV and SC insulin.
• B. Transition only after acidosis completely resolves with no overlap.
• C. Transition after exactly 24 hours of IV insulin regardless of labs.
• D. Continue IV insulin until discharge.

Answer: (A)

The timing of switching from IV insulin to subcutaneous insulin in DKA hinges on stability and safety. The best transition point is when the patient can tolerate oral intake and their blood glucose is nearing the target range, with a planned overlap where subcutaneous insulin is started before stopping the IV infusion. This overlap is crucial because SC insulin takes effect more slowly than IV insulin, and the overlap prevents a gap in insulin coverage that could allow glucose and ketones to rise again.

In practice, you begin subcutaneous rapid-acting insulin while continuing IV insulin for about 1–2 hours, then stop the IV once the SC insulin has begun to work and the patient remains in a controlled, stable state. Do not wait for the acidosis to completely resolve without overlap, because ketosis and acidosis can lag behind glucose control and a gap in insulin can cause relapse. Likewise, transitions should be individualized rather than adhering to a fixed time like exactly 24 hours, and continuing IV insulin until discharge isn’t necessary once coverage with subcutaneous insulin is established and the patient is eating and stable.