Insulin Drip Dosing Protocol
The recommended starting dose for an insulin drip is 0.05-0.1 units/kg/hour, with subsequent adjustments based on blood glucose monitoring every 1-2 hours to maintain target glucose levels between 140-180 mg/dL in most hospitalized patients. 1
Initial Dosing
Standard Starting Protocol:
- Weight-based approach: 0.05-0.1 units/kg/hour 2
- Fixed dose approach: Start with 1-2 units/hour for most patients 3
Special Considerations for Initial Dosing:
- For severe hyperglycemia (>300 mg/dL): Consider starting at the higher end of the range
- For elderly patients or those with renal impairment: Start at lower dose (0.05 units/kg/hour) 2
- For patients at high risk of hypoglycemia: Start at 0.05 units/kg/hour
Titration Algorithm
Blood glucose should be monitored hourly until stable, then every 2 hours. Adjust the insulin infusion rate according to the following protocol:
| Blood Glucose (mg/dL) | Action |
|---|---|
| <70 | Stop insulin infusion, administer 25g glucose IV, recheck in 15 min |
| 70-100 | Decrease rate by 50% |
| 101-140 | Decrease rate by 25% |
| 141-180 | No change (target range) |
| 181-220 | Increase rate by 25% |
| 221-300 | Increase rate by 50% |
| >300 | Increase rate by 75%, notify provider |
Target Glucose Range
The American Diabetes Association recommends:
- For most critically ill patients: 140-180 mg/dL 1
- For selected non-critically ill patients: 100-140 mg/dL (if achievable without hypoglycemia)
Monitoring Requirements
- Check blood glucose hourly until stable in target range for 4 hours
- Once stable, check every 2 hours
- Monitor more frequently with:
- Significant changes in clinical status
- Changes in nutrition (NPO status, enteral/parenteral feeding changes)
- Addition of medications that affect glucose (steroids, vasopressors)
Special Clinical Scenarios
Perioperative Management:
- Continue insulin drip until patient is stable and able to resume oral intake 1
- When transitioning to subcutaneous insulin, give first dose 1-2 hours before discontinuing the drip 1
Diabetic Ketoacidosis (DKA):
- Initial dose: 0.1 units/kg/hour IV infusion 1
- Target glucose: 150-200 mg/dL until resolution of DKA 1
- Do not discontinue insulin even if glucose normalizes before ketoacidosis resolves
Enteral/Parenteral Nutrition:
- For patients receiving continuous tube feedings, calculate insulin requirements as approximately 1 unit for every 10-15g carbohydrate per day 1
- Never discontinue insulin drip abruptly when feedings are stopped, especially in type 1 diabetes
Transition to Subcutaneous Insulin
When transitioning from IV to subcutaneous insulin:
- Calculate total daily insulin requirement based on average hourly rate over previous 6-8 hours
- Multiply hourly rate by 24 to estimate 24-hour insulin requirement
- Give 50-80% as basal insulin and remainder as prandial insulin 1
- Administer first subcutaneous dose 1-2 hours before discontinuing the insulin drip 1
Hypoglycemia Management
If hypoglycemia occurs (blood glucose <70 mg/dL):
- Stop insulin infusion immediately
- Administer 25g of D50W IV push
- Recheck blood glucose in 15 minutes
- Resume insulin at 50% of previous rate once blood glucose >100 mg/dL
Common Pitfalls and Caveats
- Failure to adjust for changes in clinical status: Insulin requirements may change dramatically with stress, infection, or steroid administration
- Inadequate glucose monitoring: Insufficient monitoring can lead to dangerous glucose fluctuations
- Abrupt discontinuation: Never abruptly stop an insulin drip, especially in type 1 diabetes patients
- Delayed transition to subcutaneous insulin: Ensure overlap between IV and subcutaneous insulin to prevent rebound hyperglycemia
- Inadequate glucose supplementation: Ensure adequate glucose administration during insulin infusion to prevent hypoglycemia
By following this structured approach to insulin drip management, clinicians can effectively control blood glucose while minimizing the risks of both hyperglycemia and hypoglycemia in hospitalized patients.