Why are non-diabetic patients placed on sliding scale insulin (SSI) while fasting?

Why Non-Diabetic Patients Receive Sliding Scale Insulin While Fasting

Sliding scale insulin (SSI) should not be used as monotherapy for non-diabetic fasting patients, as it is ineffective and may lead to poor glycemic control. 1, 2

Understanding Hospital Hyperglycemia in Non-Diabetics

Non-diabetic patients may develop stress-induced hyperglycemia during hospitalization due to:

• Acute illness or surgery triggering stress hormone release
• Medications (particularly glucocorticoids)
• Initiation of enteral or parenteral nutrition
• Other medications like octreotide or immunosuppressives 1

Evidence Against Sliding Scale Insulin

The traditional sliding-scale insulin approach has significant drawbacks:

• It's reactive rather than preventive, treating hyperglycemia after it occurs 1
• Studies show it's ineffective as monotherapy 1, 3
• It leads to rapid blood glucose fluctuations, exacerbating both hyper- and hypoglycemia 1
• A meta-analysis found SSI alone or in combination with other medications provided no benefits in blood glucose control and increased hyperglycemic events 3
• When used alone, SSI regimens are associated with a 3-fold higher risk of hyperglycemic episodes compared to no pharmacologic regimen 4

Recommended Approach for Non-Diabetic Patients with Hyperglycemia

For non-diabetic patients who develop hyperglycemia while fasting:

1. Initial monitoring: Initiate glucose monitoring with orders for correction insulin in any patient not known to be diabetic who receives therapy associated with high risk for hyperglycemia 1

2. If hyperglycemia persists: If hyperglycemia is documented and persistent, initiate basal/bolus insulin therapy. Such patients should be treated to the same glycemic targets as patients with known diabetes 1

3. For NPO/fasting patients: A basal plus correction insulin regimen is recommended with a reduced total daily dose of 0.1-0.15 units/kg/day, primarily as basal insulin 2

4. Follow-up: Patients with hyperglycemia in the hospital who do not have a diagnosis of diabetes should have appropriate plans for follow-up testing and care documented at discharge 1

Common Pitfalls to Avoid

• Using SSI as monotherapy: The American Diabetes Association advises against using SSI as the sole therapy, as it leads to poor outcomes 2
• Failing to adjust regimens: Sliding-scale insulin regimens are often prescribed on admission and used throughout the hospital stay without modification, even when control remains poor 1
• Inadequate monitoring: Monitor blood glucose every 4-6 hours when the patient is NPO, and adjust insulin doses based on patterns of glycemic control 2
• Ignoring persistent hyperglycemia: If hyperglycemia is documented and persistent in non-diabetic patients, basal/bolus insulin therapy should be initiated 1

Best Practice Approach

For non-diabetic fasting patients with stress-induced hyperglycemia:

1. Monitor blood glucose levels regularly (every 4-6 hours)
2. If hyperglycemia persists, use a weight-based basal insulin regimen (0.1-0.15 units/kg/day) with correction doses
3. Avoid using sliding scale insulin alone
4. Ensure follow-up testing after discharge to rule out undiagnosed diabetes

This approach aligns with current guidelines and provides better glycemic control while minimizing the risks associated with sliding scale insulin monotherapy.