What is the effect of D5 (Dextrose 5%) at 100 ml/hr on serum glucose levels?

Effect of D5 Infusion on Serum Glucose Levels

D5 (5% dextrose solution) administered at 100 ml/hr raises serum glucose by approximately 9 mg/dl above fasting levels, which is a clinically significant but modest increase that should be considered when managing glucose levels in hospitalized patients. 1

Understanding D5 Infusion Effects

The effect of D5 infusion on serum glucose levels has been well-documented in research:

• A 5% dextrose solution (D5W) infused at 100 ml/hr increases serum glucose by a mean of 9 mg/dl above fasting levels 1
• When the infusion rate is doubled to 200 ml/hr, the mean serum glucose elevation increases to 24 mg/dl above fasting levels 1
• This relationship appears to be dose-dependent, with higher infusion rates causing proportionally greater increases in serum glucose

Clinical Implications

This knowledge has several important clinical applications:

1. Interpreting Glucose Readings: When assessing glucose levels in patients receiving D5 infusions, clinicians should account for this expected elevation when determining if values are truly abnormal.

2. Detecting Glucose Intolerance: Serum glucose levels that exceed 20 mg/dl above fasting levels (which is 3 standard deviations above the mean) in patients receiving D5 at 100 ml/hr may indicate subclinical glucose intolerance 1

3. Hospital Glucose Management: For hospitalized patients, the American Diabetes Association recommends:

   • Target glucose range of 140-180 mg/dl for most critically and non-critically ill patients 2
   • More stringent goals (110-140 mg/dl or 100-180 mg/dl) may be appropriate for selected patients if achievable without significant hypoglycemia 2

Practical Considerations

• Monitoring Requirements: Point-of-care glucose monitoring should be performed before meals in patients who are eating; in those not eating, monitoring every 4-6 hours is advised 2

• Fluid Management: When using dextrose-containing solutions, maintain appropriate fluid requirements of approximately 25-30 ml/kg/24h 3

• Concentration Considerations: Lower concentration dextrose solutions (like D10) offer several advantages over higher concentration solutions, including fewer side effects and more physiologic glucose correction 3

Common Pitfalls to Avoid

• Overestimating Normal Variation: Remember that serum glucose elevations greater than 20 mg/dl above fasting levels with D5 at 100 ml/hr may indicate glucose intolerance rather than normal response to the infusion 1

• Ignoring Measurement Limitations: Point-of-care blood glucose meters are not as accurate as laboratory analyzers and can be affected by perfusion, edema, anemia, and several medications commonly used in hospitals 2

• Failing to Consider Alternatives: For hypoglycemia management, D10 may be preferable to higher concentration solutions like D50, as it provides similar efficacy with fewer side effects and lower risk of complications 3, 4, 5

By understanding the expected effect of D5 infusion on serum glucose levels, clinicians can more accurately interpret glucose readings, detect abnormal glucose metabolism, and make appropriate adjustments to glucose management protocols.