No, Do Not Administer Dextrose at CBG 91 mg/dL
With a capillary blood glucose (CBG) of 91 mg/dL, you should NOT administer dextrose (D50 or any concentration), as this level is well above the hypoglycemia threshold and treatment would cause unnecessary hyperglycemia. 1, 2
Definition of Hypoglycemia Requiring Treatment
- Hypoglycemia is defined as blood glucose ≤70 mg/dL, and treatment should only be initiated when glucose falls below this threshold 1, 2
- Your current CBG of 91 mg/dL is 21 mg/dL above the treatment threshold, placing the patient in a safe, normal glycemic range 1, 2
- The American Diabetes Association specifically recommends treatment be repeated at 15-minute intervals only until blood glucose returns to ≥70 mg/dL, which your patient has already exceeded 1, 2
Why Administering Dextrose Now Would Be Harmful
- Administering 25 g of D50 (half vial) at a CBG of 91 mg/dL would cause iatrogenic hyperglycemia, which increases morbidity and mortality in critically ill patients 1
- A single dose of 25 g D50 can increase blood glucose by approximately 100 mg/dL (4 mg/dL per gram × 25 g), potentially raising your patient's glucose to ~190 mg/dL 3
- Recent evidence shows that D50 administration commonly causes rebound hyperglycemia, with mean peak glucose of 12.2 mmol/L (220 mg/dL) and maximum readings up to 22.6 mmol/L (407 mg/dL) within 5 minutes 4
- Glycemic variability from unnecessary dextrose administration is independently associated with increased mortality in critically ill patients 1
Appropriate Monitoring Strategy
- Continue monitoring CBG at the scheduled 2-hour interval without intervention 1
- If the patient is on insulin or sulfonylureas and you're concerned about recurrent hypoglycemia, consider whether the next scheduled meal or snack timing is appropriate 1
- Only treat if CBG falls below 70 mg/dL (<100 mg/dL in neurologic injury patients) 1
If Future Hypoglycemia Occurs (CBG <70 mg/dL)
- For conscious patients able to swallow: Administer 15-20 g oral glucose (glucose tablets preferred) 2
- For unconscious or unable-to-swallow patients: Administer 10-20 g IV dextrose, titrated to avoid overcorrection 1
- Recheck glucose in 15 minutes and repeat treatment only if still <70 mg/dL 1, 2
- Lower concentration dextrose solutions (10% or 25%) in 5 g aliquots are preferable to D50 as they result in lower post-treatment glucose levels and less overcorrection 5, 6
Common Pitfall to Avoid
The critical error here would be treating a "normal" glucose level prophylactically, which transforms appropriate glycemic control into dangerous hyperglycemia with associated increased morbidity 1, 4. The 2-hour interval until next measurement is appropriate for a stable glucose of 91 mg/dL 1.