At what serum glucose level should D5 (Dextrose 5%) be administered when managing Diabetic Ketoacidosis (DKA) with insulin?

Serum Glucose Threshold for D5 Administration in DKA Management

When managing diabetic ketoacidosis (DKA) with insulin, dextrose 5% (D5) should be administered when serum glucose reaches 250 mg/dL to prevent hypoglycemia while continuing insulin therapy to resolve ketosis. 1, 2

Rationale for D5 Administration in DKA

• Insulin therapy must be continued until complete resolution of ketoacidosis (pH >7.3, bicarbonate ≥18 mEq/L, and anion gap ≤12 mEq/L), even when glucose levels fall below 250 mg/dL 2, 3
• Ketonemia typically takes longer to clear than hyperglycemia, necessitating continued insulin therapy even after glucose normalizes 1, 3
• Adding dextrose when glucose falls below 250 mg/dL allows continued insulin administration to resolve ketosis while preventing hypoglycemia 1, 3

Fluid Management Protocol

• Initial fluid resuscitation should use 0.9% NaCl or other crystalloid at a clinically appropriate rate 1
• When serum glucose reaches 250 mg/dL, change fluid to 5% dextrose with 0.45-0.75% NaCl 1
• Continue potassium supplementation in the D5 solution as needed to maintain serum K+ between 4-5 mmol/L 1

Insulin Management During DKA Resolution

• Continue insulin infusion at 0.1 unit/kg/hour even after glucose falls below 250 mg/dL 2, 3
• Target glucose between 150-200 mg/dL until DKA resolution parameters are met 1, 3
• Do not interrupt insulin infusion when glucose levels fall, as this is a common cause of persistent or worsening ketoacidosis 2, 3

Monitoring During Treatment

• Check electrolytes, renal function, venous pH, osmolality, and glucose every 2-4 hours until stable 1
• Direct measurement of β-hydroxybutyrate in blood is the preferred method for monitoring ketosis resolution 2, 3
• Monitor for signs of hypoglycemia, hypokalemia, and other electrolyte abnormalities 2, 3

Common Pitfalls to Avoid

• Premature discontinuation of insulin therapy before complete resolution of ketosis can lead to recurrence of DKA 2, 3
• Failure to add dextrose when glucose falls below 250 mg/dL while continuing insulin therapy 1
• Interrupting insulin infusion when glucose levels fall, which can worsen ketoacidosis 2, 3
• Inadequate monitoring of electrolytes, particularly potassium, during treatment 1, 2

Resolution Parameters

• DKA resolution requires: glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH >7.3, and anion gap ≤12 mEq/L 2, 3
• Once DKA is resolved and patient can eat, transition to subcutaneous insulin with appropriate overlap 1, 3

Special Considerations

• In euglycemic DKA (glucose <250 mg/dL with ketoacidosis), D5 should be started alongside 0.9% NaCl at the beginning of insulin treatment 1, 4
• For pediatric patients, the threshold for adding dextrose may be similar, but fluid rates should be adjusted appropriately for weight 1