What is the recommended rate of D5NS (5% Dextrose in Normal Saline) administration for treating hypoglycemia due to insulin overdose?

D5NS Infusion Rate for Insulin Overdose-Induced Hypoglycemia

For insulin overdose causing hypoglycemia, administer an initial dextrose bolus followed by a continuous D10W infusion at 100 mL/kg per 24 hours (approximately 4.2 mL/kg/hour), titrated to maintain blood glucose 100-180 mg/dL, with monitoring every 30-60 minutes initially. Note that D5NS is suboptimal—D10W is the preferred concentration for continuous infusion.

Initial Bolus Treatment

• Administer 0.5-1.0 g/kg of dextrose as an immediate bolus (equivalent to 10-20 mL/kg of D5W, or 2-4 mL/kg of D25W) 1, 2
• Traditional fixed dosing of 25-50 mL of D50W (12.5-25 g) is commonly used but often causes overcorrection 3
• Titrated replacement is superior: Give 5-10 g aliquots of dextrose every 1-2 minutes until symptoms resolve, rather than a single large bolus 4, 2
• This titrated approach prevents overcorrection and achieves lower final blood glucose levels (112 mg/dL vs 169 mg/dL) compared to traditional bolus dosing 4

Continuous Infusion Protocol

D10W is the recommended concentration for continuous infusion, not D5NS:

• Start D10W at 100 mL/kg per 24 hours (equivalent to 7 mg/kg per minute or approximately 4.2 mL/kg/hour) 1
• If using D5NS due to availability constraints, double the rate to approximately 8.4 mL/kg/hour to deliver equivalent dextrose
• Titrate the infusion rate to maintain blood glucose 100-180 mg/dL 1, 2
• Older children and adults typically require substantially lower doses than weight-based calculations suggest 1, 2

Critical Monitoring Requirements

Insulin overdose requires intensive glucose monitoring due to prolonged insulin action:

• Monitor blood glucose every 30-60 minutes initially during the acute phase 5
• Once stable, transition to every 1-2 hours during continuous infusion 4, 2
• Monitor serum potassium and sodium levels carefully as dextrose administration can cause electrolyte shifts 1, 2
• Insulin glargine overdoses may cause hypoglycemia lasting >100 hours due to depot effects at injection sites 5

Target Blood Glucose Range

• Maintain blood glucose 100-180 mg/dL for most patients 1
• Avoid overcorrection: 32% of hypoglycemic episodes corrected with standard D50W protocols resulted in hyperglycemia >150 mg/dL 6
• Avoid both hypoglycemia and hyperglycemia, as both have adverse central nervous system effects 1

Special Considerations for Insulin Overdose

Insulin overdose differs from routine hypoglycemia management:

• Expect prolonged hypoglycemia requiring continuous dextrose infusion for 24-100+ hours depending on insulin type 5
• Long-acting insulin (glargine, detemir) creates a subcutaneous depot requiring extended treatment 5
• Consider octreotide as adjunctive therapy (50-100 mcg subcutaneously every 6-8 hours) for refractory cases to suppress endogenous insulin secretion triggered by dextrose infusion 5
• The blood glucose response to rescue dextrose is approximately 4 mg/dL per gram of dextrose administered in critically ill patients 6

Prevention of Rebound Hypoglycemia

• Reduce infusion rate by 50% over the final 30 minutes before discontinuing dextrose to prevent rebound hypoglycemia 2
• If dextrose infusion must be interrupted, immediately start D10W at 50 mL/hour as a bridge 2
• Never abruptly discontinue dextrose infusion in insulin overdose patients 2

Why D10W is Preferred Over D5NS

• D50W is highly irritating to veins; dilution to D10W or D25W is preferable 1, 2
• D10W provides adequate dextrose delivery at reasonable fluid volumes 1
• D5NS delivers insufficient dextrose concentration for insulin overdose, requiring excessive fluid volumes that risk volume overload
• Normal saline component in D5NS is unnecessary unless concurrent sodium replacement is needed 1