Initial Treatment of Diabetic Ketoacidosis (DKA)
The initial treatment for diabetic ketoacidosis (DKA) should begin with aggressive fluid resuscitation using balanced crystalloids or normal saline at 10-20 mL/kg/hour for the first hour (not exceeding 50 mL/kg in the first 4 hours), followed by intravenous regular insulin at 0.1 units/kg/hour without bolus. 1
Diagnosis and Classification
Before initiating treatment, confirm DKA diagnosis based on:
- Hyperglycemia (glucose >250 mg/dL), though euglycemic DKA can occur
- Metabolic acidosis (pH <7.3, bicarbonate <18 mEq/L)
- Presence of ketones in blood or urine
- Elevated anion gap (>10-12 mEq/L) 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 |
Initial Treatment Algorithm
1. Fluid Resuscitation
- First line: Balanced crystalloids rather than 0.9% saline (reduces hyperchloremic metabolic acidosis) 1, 2
- Initial rate: 10-20 mL/kg/hour for first hour, not exceeding 50 mL/kg in first 4 hours 1
- If hyperglycemic: Begin with 0.9% NaCl, then transition to 0.45% NaCl 1
- When glucose reaches 250-300 mg/dL: Switch to 5% dextrose with 0.45% NaCl 1
Recent research shows balanced fluids are associated with faster DKA resolution compared to normal saline (13 hours vs. 17 hours) 2
2. Insulin Therapy
- Initial dosing: Continuous IV infusion of regular insulin at 0.1 units/kg/hour (typically 5-7 units/hour for adults) 1
- No bolus recommended: Start directly with continuous infusion 1
- Target: Reduce glucose by 50-75 mg/dL per hour 1
3. Electrolyte Management
- Potassium: Replace based on serum levels
- If K+ <3.3 mEq/L: Hold insulin, give potassium until >3.3 mEq/L
- If K+ 3.3-5.3 mEq/L: Add 20-30 mEq potassium per liter of IV fluid
- If K+ >5.3 mEq/L: No immediate replacement, monitor closely 1
- Monitor electrolytes: Every 2-4 hours initially 1
- Calculate corrected sodium: For each 100 mg/dL glucose >100 mg/dL, add 1.6 mEq to sodium value 1
4. Monitoring
- Vital signs: Every hour (heart rate, blood pressure, respiratory rate, mental status) 1
- Laboratory tests: Every 2-4 hours (electrolytes, BUN, creatinine, venous pH) 1
- Target decrease in serum osmolality should not exceed 3 mOsm/kg/hour 1
Important Caveats and Pitfalls
Bicarbonate Administration
- Not recommended for routine use in DKA management 1
- Reserve only for severe acidosis (pH <6.9) or life-threatening hyperkalemia
Cerebral Edema Risk
- Occurs in 0.5-0.9% of DKA episodes, particularly in children 1
- Warning signs: Headache, decreased mental status, irritability, abnormal pupillary responses, rising BP with decreasing heart rate 1
- Prevention: Avoid excessive fluid administration and rapid glucose correction
ICU Admission Criteria
Admit to ICU if any of the following:
- pH <7.00
- Altered mental status
- Hemodynamic instability
- Severe complications
- Severe hyperosmolarity (>320 mOsm/kg) 1
Resolution Criteria
DKA is considered resolved when:
- Glucose <200 mg/dL
- Bicarbonate ≥18 mEq/L
- Venous pH >7.3 1
Transition to Subcutaneous Insulin
- Administer basal insulin 2-4 hours before stopping IV insulin
- Ensure overlap between IV and subcutaneous insulin to prevent rebound hyperglycemia 1
Special Considerations
- Euglycemic DKA: Can occur especially with SGLT2 inhibitor use; diagnosis requires ketosis and acidosis even with normal glucose levels 3
- Pregnancy, renal disease, heart failure: May require modified fluid and electrolyte management 4
- Cost-effective approach: Some institutions have developed protocols using less frequent laboratory monitoring (every 2-3 hours for glucose and potassium) with good outcomes 5