Management of Diabetic Ketoacidosis (DKA)
The management of diabetic ketoacidosis requires immediate fluid resuscitation with isotonic saline (15-20 ml/kg/hour initially), followed by insulin therapy (0.1 units/kg/hour continuous IV infusion without bolus), electrolyte replacement, and identification and treatment of underlying causes. 1
Diagnosis and Classification
DKA is diagnosed based on the following criteria:
- Blood glucose >250 mg/dL
- Arterial pH <7.3
- Bicarbonate <15 mEq/L
- Moderate ketonemia or ketonuria 1
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 |
Step-by-Step Management 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
- Calculate corrected sodium: Measured sodium + 1.6 × [(glucose mg/dl - 100)/100] 1
- Balanced crystalloid solutions are preferred over normal saline for maintenance fluid therapy 1
2. Insulin Therapy
- Start continuous IV regular insulin at 0.1 units/kg/hour without an initial bolus to avoid rapid glucose reduction and cerebral edema 1
- For patients with complicated DKA (chronic kidney disease, heart failure), consider reduced rate of 0.05 units/kg/hour 1
- Target glucose reduction rate: 50-70 mg/dL/hour 1
- When glucose falls below 200-250 mg/dL, add dextrose to IV fluids while continuing insulin to clear ketones 1
- For uncomplicated DKA in appropriate settings, subcutaneous rapid-acting insulin analogs may be used 1
3. Electrolyte Management
- Potassium: Begin replacement when serum K+ <5.5 mEq/L
- Add 20-30 mEq/L potassium to IV fluids (2/3 KCl and 1/3 KPO₄) 1
- Hold potassium if serum K+ >5.5 mEq/L or if anuria is present
- Phosphate: Generally included in replacement as KPO₄, especially with severe hypophosphatemia 1
- Bicarbonate: Not routinely recommended unless pH <7.0 2
4. Monitoring
- Hourly monitoring:
- Vital signs
- Neurological status
- Blood glucose
- Fluid input/output 1
- Every 2-4 hours monitoring:
- Electrolytes
- BUN, creatinine
- Venous pH 1
5. Resolution Criteria
DKA is considered resolved when:
- Glucose <200 mg/dL
- Serum bicarbonate ≥18 mEq/L
- Venous pH >7.3 1
Complications to Watch For
1. Cerebral Edema
- Rare but potentially fatal (0.7-1.0% in children)
- 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
- Signs: Headache, altered mental status, seizures, bradycardia, hypertension
2. Other Complications
- Hypoglycemia: Monitor glucose closely when adding dextrose
- Hypokalemia: Can develop rapidly during insulin therapy
- Fluid overload: Monitor for signs of heart failure, especially in elderly patients 1, 3
Identifying and Treating Underlying Causes
Common precipitating factors:
- Infection
- Missed insulin doses
- New-onset diabetes
- Medication non-compliance
- Myocardial infarction
- Stroke
- Trauma 1, 4
Patient Education Before Discharge
- Diabetes self-management
- Blood glucose monitoring
- When to seek medical attention
- Sick-day management
- Proper medication administration 1
- Schedule follow-up appointment prior to discharge 1
Pitfalls and Caveats
- Euglycemic DKA: Can occur especially with SGLT2 inhibitor use - don't rule out DKA based solely on glucose levels 4
- Overly aggressive fluid resuscitation: May lead to cerebral edema, especially in children
- Insulin bolus: Avoid initial bolus to prevent rapid glucose reduction and cerebral edema 1
- Bicarbonate therapy: Generally not recommended unless severe acidosis (pH <7.0) 2
- Inadequate potassium replacement: Can lead to life-threatening hypokalemia during insulin therapy 1, 3
- Premature discontinuation of insulin: Continue insulin until acidosis resolves, even after glucose normalizes 1