Treatment of Diabetic Ketoacidosis (DKA)
The standard treatment for diabetic ketoacidosis requires fluid resuscitation with isotonic saline followed by continuous intravenous insulin infusion at 0.1 units/kg/hour without an initial bolus, along with appropriate electrolyte replacement and monitoring. 1
Diagnostic Criteria
- Blood glucose >250 mg/dL
- Arterial pH <7.3
- Bicarbonate <15 mEq/L
- Moderate ketonemia or ketonuria
DKA severity classification:
| Parameter | Mild | Moderate | Severe |
|---|---|---|---|
| Arterial pH | 7.25-7.30 | 7.00-7.24 | <7.00 |
| Bicarbonate (mEq/L) | 15-18 | 10-14 | <10 |
| Mental Status | Alert | Alert/drowsy | Stupor/coma |
Treatment Algorithm
1. Fluid Therapy
- Initial resuscitation: Isotonic saline at 15-20 ml/kg/hour for the first hour 1
- Subsequent fluid therapy: 0.45% saline at 4-14 ml/kg/hour based on corrected sodium levels 1
- Newer evidence: Balanced crystalloid solutions may lead to faster resolution of acidosis than normal saline 2, 3
- Calculate corrected sodium using: Measured sodium + 1.6 × [(glucose mg/dl - 100)/100] 1
2. Insulin Administration
- Standard approach: Continuous IV regular insulin at 0.1 units/kg/hour without an initial bolus 1, 4
- Avoids rapid glucose reduction and risk of cerebral edema
- Continue until DKA resolution (glucose <200 mg/dL, bicarbonate ≥18 mEq/L, pH >7.3) 1
- Alternative for uncomplicated DKA: Subcutaneous rapid-acting insulin analogs in emergency departments or step-down units 1
3. Electrolyte Replacement
- Potassium: Begin when serum K+ <5.5 mEq/L and adequate urine output is confirmed 1
- Add 20-30 mEq/L potassium to IV fluids (2/3 KCl and 1/3 KPO₄)
- Hypokalemia occurs in approximately 50% of patients during treatment
- Phosphate: Generally included as KPO₄, especially with severe hypophosphatemia 1
- Bicarbonate: Generally not recommended routinely
- Consider only if pH <7.0, and then add to IV fluids rather than giving as bolus 2
4. Monitoring Protocol
- Hourly monitoring:
- Vital signs
- Neurological status
- Blood glucose
- Fluid input/output
- Every 2-4 hours:
- Electrolytes
- BUN and creatinine
- Venous pH 1
Complications to Watch For
Cerebral Edema
- Rare but potentially fatal (0.7-1.0% in children) 1
- Prevention:
- Avoid too rapid correction of serum osmolality (not exceeding 3 mOsm/kg/h)
- Limit initial vascular expansion to 50 ml/kg in first 4 hours in pediatric patients 1
- Monitor for headache, altered mental status, seizures, or bradycardia
Other Complications
- Hypoglycemia: Monitor glucose closely during insulin infusion 4
- Hypokalemia: Can develop rapidly during treatment 1, 4
- Fluid overload: Particularly in patients with cardiac or renal disease 1
Resolution Criteria
DKA is considered resolved when:
- Glucose <200 mg/dL
- Serum bicarbonate ≥18 mEq/L
- Venous pH >7.3 1
Post-Resolution Management
- Identify and treat underlying causes (infection, missed insulin, new diagnosis) 1
- Transition to subcutaneous insulin after DKA resolution
- Provide education on:
- Diabetes self-management
- Blood glucose monitoring
- Sick-day management
- When to seek medical attention 1
Common Pitfalls
- Insulin bolus administration: Avoid initial bolus to prevent rapid glucose reduction and cerebral edema 1
- Inadequate fluid resuscitation: Underestimating volume depletion can delay recovery
- Neglecting potassium replacement: Can lead to dangerous hypokalemia during treatment 1, 4
- Overuse of bicarbonate: May worsen ketosis, hypokalemia, and increase risk of cerebral edema 2
- Premature discontinuation of IV insulin: Continue until DKA resolution criteria are met 1