What is the recommended starting dose for insulin (regular insulin) infusion?

Recommended Starting Dose for Regular Insulin Infusion

For adults with diabetic ketoacidosis (DKA) or hyperglycemic hyperosmolar state (HHS), start with a continuous intravenous infusion of regular insulin at 0.1 units/kg/hour without an initial bolus, or alternatively give an initial bolus of 0.15 units/kg followed by 0.1 units/kg/hour infusion. 1

Standard Dosing Protocol for DKA/HHS

Initial Approach

• Exclude hypokalemia first: Do not start insulin if potassium is <3.3 mEq/L 1
• Adult dosing: 0.1 units/kg/hour continuous IV infusion of regular insulin (approximately 5-7 units/hour in a 70 kg patient) 1
• Optional bolus: 0.15 units/kg IV bolus may be given initially, though this is not mandatory if adequate infusion rates are used 1
• Pediatric dosing: 0.1 units/kg/hour continuous infusion WITHOUT an initial bolus 1

Dose Titration Strategy

• Expected glucose decline: 50-75 mg/dL per hour 1
• If inadequate response: If plasma glucose does not fall by 50 mg/dL in the first hour, check hydration status and double the insulin infusion rate hourly until achieving steady glucose decline of 50-75 mg/dL/hour 1
• Maintenance phase: When glucose reaches 200 mg/dL (DKA) or 250 mg/dL (HHS), decrease infusion rate and add dextrose-containing fluids to maintain glucose in target range until resolution 1

Alternative Dosing for Specific Clinical Scenarios

Lower-Dose Regimen (Pediatric Consideration)

• 0.05 units/kg/hour may be considered in children to achieve more gradual osmolality reduction and potentially reduce cerebral edema risk, though 0.1 units/kg/hour remains standard 2
• Both doses achieve satisfactory improvement in acidosis and ketosis 2

Higher-Dose Regimen (Severe Cases)

• 0.14 units/kg/hour (approximately 10 units/hour in a 70 kg patient) without a priming dose is effective and eliminates the need for supplemental boluses 3
• This approach may be preferred when a priming dose is not feasible 3

Perioperative/General Hyperglycemia Management

Non-DKA Insulin Infusion

• Starting rate: 0.05 units/kg/hour for general hyperglycemia management 1
• Target glucose: Maintain between 150-200 mg/dL in most hospitalized patients 1
• Transition timing: Continue IV insulin until patient is stable for at least 24 hours and able to resume oral feeding 1

Transition to Subcutaneous Insulin

• Timing: Stop IV insulin when infusion rate is ≤0.5 units/hour 1
• Dosing calculation: Total daily subcutaneous dose equals approximately 50-80% of the 24-hour IV insulin requirement 1
• Distribution: Split as 50% basal (long-acting) insulin and 50% prandial (rapid-acting) insulin 1
• Critical timing: Administer first subcutaneous basal insulin dose immediately before stopping IV infusion to prevent rebound hyperglycemia 1

Critical Pitfalls to Avoid

Dosing Errors

• Never start insulin before correcting severe hypokalemia (K+ <3.3 mEq/L), as insulin drives potassium intracellularly and can precipitate life-threatening hypokalemia 1
• Avoid inadequate initial dosing: Using less than 0.1 units/kg/hour may require supplemental boluses and delay glucose control 3
• Don't continue high infusion rates unnecessarily: If infusion rate exceeds 5 units/hour in the perioperative setting, this indicates major insulin resistance and warrants investigation 1

Monitoring Failures

• Check electrolytes every 2-4 hours during active DKA/HHS treatment, particularly potassium 1
• Monitor for cerebral edema in pediatric patients, especially with rapid osmolality changes 2
• Don't rely on urine ketones: Use venous pH and anion gap to monitor DKA resolution, as β-hydroxybutyrate converts to acetoacetate during treatment, falsely suggesting worsening ketosis 1

Transition Errors

• Never stop IV insulin abruptly: Overlap with subcutaneous basal insulin is essential 1
• Don't transition too early: Wait until glucose is stable and patient can eat 1

Special Populations

Hypertriglyceridemia-Induced Pancreatitis

• Average dosing: 0.05-0.07 units/kg/hour achieves approximately 40% triglyceride reduction at 48 hours 4
• Monitor closely: 29% incidence of hypokalemia and 9% incidence of hypoglycemia 4

Hospitalized Patients (Non-Critical)

• Insulin-naive patients: Start at 0.3-0.5 units/kg/day total daily dose, with 50% as basal insulin 5
• High-risk patients (elderly, renal failure): Use lower doses of 0.1-0.25 units/kg/day 5
• Patients on high home doses (≥0.6 units/kg/day): Reduce total daily dose by 20% to prevent hypoglycemia 5