Sliding Scale Insulin Dosing for CBG of 330 mg/dL
For a capillary blood glucose (CBG) of 330 mg/dL, 8 units of Human Actrapid insulin should be administered as per standard sliding scale protocols. 1
Rationale for Dosing Decision
The recommended correction insulin protocol for elevated blood glucose levels follows a tiered approach:
- For CBG 251-300 mg/dL: 6 units
- For CBG >300 mg/dL: 8 units 1
Since the patient's CBG is 330 mg/dL, which is >300 mg/dL, the appropriate dose is 8 units of Human Actrapid insulin.
Important Considerations When Using Sliding Scale Insulin
Limitations of Sliding Scale Approach
While sliding scale insulin is commonly used in hospitals, it has significant limitations:
- Treats hyperglycemia reactively rather than preventively 2
- Often used without modification throughout hospital stays despite poor control 2
- Associated with higher rates of hyperglycemic episodes when used alone 3
- May lead to rapid fluctuations in blood glucose levels 2
Monitoring Requirements
After administering the correction dose:
- Monitor blood glucose every 1-2 hours until glucose values stabilize 2
- Once stable, monitor every 4 hours 2
- Be cautious with point-of-care testing of capillary blood as it may not accurately reflect arterial blood glucose values 2
Risk of Hypoglycemia
When using sliding scale insulin, be vigilant for hypoglycemia:
- If blood glucose drops below 70 mg/dL, stop insulin and administer 25g of glucose 1
- Recheck blood glucose in 15 minutes 1
- African American race and low serum albumin are independent risk factors for hypoglycemic episodes 3
More Effective Approaches to Consider
For ongoing management, consider transitioning from sliding scale alone to a more effective regimen:
- Basal-bolus insulin therapy has shown better glycemic control than sliding scale alone 2, 4
- For patients with established insulin requirements, sliding scale monotherapy is ineffective 2
- A basal-plus approach (basal insulin with correction doses) may be preferred for patients with mild hyperglycemia or decreased oral intake 2
Implementation Tips
- Verify the elevated glucose reading with a second measurement before administering insulin 1
- Document administration time and dose carefully to avoid errors 5
- If hyperglycemia persists despite sliding scale insulin, consider adjusting the regimen or adding basal insulin 2
- For persistent hyperglycemia (>180 mg/dL), a protocolized approach to blood glucose management is recommended 2
Remember that while the immediate action is to administer 8 units of Human Actrapid for the CBG of 330 mg/dL, ongoing assessment of the patient's glycemic control and insulin regimen is essential for optimal outcomes.