For a patient with a basal insulin pump requirement of 14 U per day who will be NPO, what dose of insulin glargine (Lantus) should be administered?

Basal Insulin Dosing for NPO Patients Transitioning from Insulin Pump Therapy

For a patient with a basal insulin pump requirement of 14 units per day who will be NPO, administer approximately 10–11 units of insulin glargine (Lantus) once daily, representing 75–80% of the total pump basal dose. 1

Rationale for Dose Reduction

• When transitioning from continuous subcutaneous insulin infusion (pump therapy) to subcutaneous basal insulin in the perioperative or NPO setting, the recommended starting dose is 75–80% of the total 24-hour pump basal rate to reduce hypoglycemia risk while maintaining essential basal coverage. 1

• The 24-hour basal dose from the pump menu (14 units in this case) should be replaced with an equivalent subcutaneous injection of insulin glargine, but reduced by approximately 20–25% to account for differences in absorption kinetics and the absence of meal-related insulin needs. 1

• For NPO patients, basal insulin must never be completely withheld because it suppresses hepatic glucose production independent of food intake and prevents hyperglycemia and ketosis. 2, 3

Specific Dosing Recommendation

• Initial Lantus dose: 10–11 units once daily (75–80% of 14 units = 10.5–11.2 units, rounded to 10–11 units). 1

• Administer the first dose of Lantus at least 2 hours before discontinuing the insulin pump to ensure adequate subcutaneous absorption and prevent rebound hyperglycemia. 1, 2

• The pump should be discontinued 2 hours after the first injection of basal insulin to allow overlap and prevent insulin deficiency. 1

Monitoring and Titration Protocol

• Check capillary glucose every 4–6 hours while the patient remains NPO to guide correction insulin dosing and assess basal adequacy. 2, 3

• Target glucose range: 140–180 mg/dL for most non-critically ill hospitalized patients who are NPO. 2, 3

• If fasting or pre-meal glucose consistently exceeds 180 mg/dL, increase Lantus by 2 units every 3 days; if glucose is ≥180 mg/dL, increase by 4 units every 3 days. 2, 3

• If glucose falls below 70 mg/dL, treat immediately with 15 grams of fast-acting carbohydrate (if able to take oral intake) or intravenous dextrose, and reduce the Lantus dose by 10–20% before the next administration. 2, 3

Correction Insulin Protocol (Adjunct to Basal)

• Use rapid-acting insulin (lispro, aspart, or glulisine) as correction doses only when point-of-care glucose exceeds predefined thresholds—this is not a replacement for scheduled basal insulin. 2, 3

• Add 2 units of rapid-acting insulin for glucose >250 mg/dL and 4 units for glucose >350 mg/dL. 2, 3

• Never administer rapid-acting insulin at bedtime as a sole correction dose in NPO patients, as this markedly raises the risk of nocturnal hypoglycemia. 2, 3

Transition Back to Pump Therapy

• When resuming oral intake and transitioning back to the insulin pump, reconnect the pump and infuse the basal rate for at least 2 hours before stopping the subcutaneous Lantus to prevent insulin deficiency. 1

• Disconnection from the pump renders the patient relatively insulin deficient within 1 hour, so immediate resumption of pump basal delivery is imperative when transitioning off Lantus. 1, 4

Critical Safety Considerations

• Basal insulin is absolutely required even when NPO to prevent ketosis and maintain glucose homeostasis; complete discontinuation can precipitate diabetic ketoacidosis in insulin-dependent patients. 1, 4

• The perioperative guideline recommends administering 75–80% of the usual long-acting analog dose (or 50% of NPH dose) on the morning of surgery to reduce hypoglycemia risk while maintaining target glucose of 80–180 mg/dL. 1, 2

• For patients with type 1 diabetes or insulin-dependent type 2 diabetes, never fully discontinue basal insulin during NPO periods, as this can lead to rapid metabolic decompensation. 1, 2

Common Pitfalls to Avoid

• Do not use sliding-scale insulin as monotherapy in NPO patients; correction doses must supplement a scheduled basal insulin regimen, not replace it. 2, 3

• Do not administer the full 14-unit pump basal dose as a single subcutaneous injection without reduction, as this increases hypoglycemia risk due to differences in pharmacokinetics between pump and injection delivery. 1

• Do not delay the first Lantus injection until after pump discontinuation; the 2-hour overlap is essential to prevent insulin deficiency and rebound hyperglycemia. 1, 2

• Do not continue the same Lantus dose if the patient develops hypoglycemia; immediate dose reduction by 10–20% is required to prevent recurrent episodes. 2, 3