DKA Protocol for 80kg Female
For moderate-to-severe DKA in an 80kg adult female, initiate continuous IV regular insulin at 8 units/hour (0.1 units/kg/h) after excluding hypokalemia, preceded by a 12-unit IV bolus (0.15 units/kg), with concurrent fluid resuscitation using isotonic crystalloids. 1
Initial Assessment & Labs
Obtain immediately:
- Blood glucose, venous blood gas (pH, bicarbonate), electrolytes (especially potassium)
- BUN, creatinine, anion gap calculation
- Urine or serum ketones (beta-hydroxybutyrate preferred over nitroprusside method)
- Phosphate, calcium 1
Critical pitfall: Do NOT start insulin if potassium <3.3 mEq/L—this can precipitate life-threatening arrhythmias. Replete potassium first. 1
Insulin Therapy
For Moderate-to-Severe DKA:
- Initial IV bolus: 12 units regular insulin (0.15 units/kg × 80kg) 1
- Continuous infusion: 8 units/hour (0.1 units/kg/h × 80kg) 1
- Target glucose decline: 50-75 mg/dL per hour 1
If glucose doesn't drop by 50 mg/dL in first hour: Check hydration status; if adequate, double insulin infusion hourly until achieving steady 50-75 mg/h decline 1
When Glucose Reaches 250 mg/dL:
- Add 10% dextrose IV
- Consider reducing insulin to 4 units/hour (0.05 units/kg/h) when glucose <250 mg/dL (14 mmol/L) to reduce hypoglycemia risk 2, 3
- Continue insulin infusion until DKA resolves (don't stop just because glucose normalizes—ketoacidosis takes longer to clear) 1
For Mild DKA Alternative:
If pH >7.0 and patient alert, can use subcutaneous route:
- Priming dose: 32-48 units regular insulin (0.4-0.6 units/kg), give half IV and half SC/IM
- Maintenance: 8 units regular insulin SC/IM every hour 1
Fluid Resuscitation
Initial bolus: 1-2 liters isotonic crystalloid (0.9% saline or balanced solution like lactated Ringer's) over first 1-2 hours 4
Maintenance: Continue isotonic fluids at appropriate rate based on hydration status and hemodynamics 1
Important nuance: While traditional guidelines favor normal saline, recent evidence suggests large volumes (≥3L) may prolong ICU stay and cause hyperchloremic non-anion gap acidosis 5. Consider balanced crystalloids (lactated Ringer's) as alternative, though guideline consensus still supports either isotonic option 1.
Potassium Management
Critical monitoring: Hypokalaemia occurs in ~50% during treatment and severe hypokalaemia (<2.5 mEq/L) increases mortality 4
- **If K+ <3.3 mEq/L**: Hold insulin, give potassium 20-30 mEq/hour until >3.3 mEq/L
- If K+ 3.3-5.2 mEq/L: Add 20-30 mEq potassium to each liter of IV fluid
- If K+ >5.2 mEq/L: Hold potassium but check every 2 hours 1
Composition: Use 2/3 KCl and 1/3 KPO4 1
Bicarbonate Therapy
- pH ≥7.0: No bicarbonate needed 1
- pH <6.9: Consider bicarbonate (though evidence weak and not universally recommended) 1
- pH 6.9-7.0: Controversial—no clear benefit demonstrated 1
Phosphate Replacement
Generally not indicated as studies show no clinical outcome benefit 1
Consider replacement only if:
- Cardiac dysfunction present
- Anemia
- Respiratory depression
- Serum phosphate <1.0 mg/dL 1
Monitoring
- Blood glucose: Hourly initially
- Electrolytes, venous pH, anion gap: Every 2-4 hours 1
- Arterial blood gases: Generally unnecessary; venous pH adequate (typically 0.03 lower than arterial) 1
- Avoid nitroprusside ketone testing: Measures acetoacetate/acetone but misses beta-hydroxybutyrate (the predominant ketone). During treatment, beta-hydroxybutyrate converts to acetoacetate, falsely suggesting worsening ketosis 1
Resolution Criteria
DKA resolved when ALL of the following met:
- Glucose <200 mg/dL
- Serum bicarbonate ≥18 mEq/L
- Venous pH ≥7.3
- Anion gap closed 1
Transition to Subcutaneous Insulin
Critical timing: Must overlap IV and SC insulin by 1-2 hours to prevent rebound hyperglycemia/ketosis 1
- Calculate total daily dose from last 12 hours of IV insulin (e.g., if averaging 1.5 units/hour = 36 units/day)
- Start basal-bolus SC regimen
- Continue IV insulin for 1-2 hours after first SC dose
- If NPO: Continue IV insulin with supplemental SC regular insulin every 4 hours (5 units per 50 mg/dL above 150 mg/dL, max 20 units for glucose >300 mg/dL) 1
Special Considerations
SGLT2 inhibitor use: Increases risk of euglycemic DKA (normal glucose with ketoacidosis)—maintain high suspicion 2, 6
Renal failure/dialysis: Requires modified approach with careful fluid and electrolyte management 2
Pregnancy: Requires specialized protocol—lower threshold for DKA diagnosis and more aggressive management
Common pitfall: Stopping insulin when glucose normalizes before ketoacidosis clears—this causes rebound DKA 1