What is the initial management protocol for Diabetic Ketoacidosis (DKA)?

Initial Management Protocol for Diabetic Ketoacidosis (DKA)

Begin immediate fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour, followed by continuous IV regular insulin at 0.1 units/kg/hour once potassium is confirmed >3.3 mEq/L. 1, 2

Diagnostic Confirmation

Before initiating treatment, confirm DKA diagnosis with:

• Blood glucose >250 mg/dL (though euglycemic variants exist) 1, 3
• Arterial pH <7.3 1, 3
• Serum bicarbonate <15 mEq/L 1, 3
• Moderate ketonuria or ketonemia - measure β-hydroxybutyrate specifically, as nitroprusside-based tests are unreliable 3
• Anion gap >10-12 mEq/L 3

Obtain initial labs: arterial blood gases, complete blood count, comprehensive metabolic panel with calculated anion gap, serum ketones (β-hydroxybutyrate), BUN/creatinine, urinalysis, and ECG. 1, 3

Fluid Resuscitation Algorithm

Hour 1:

• Administer 1-1.5 liters of 0.9% NaCl (15-20 mL/kg/hour) to restore intravascular volume and renal perfusion 1, 2
• In pediatric patients (<20 years), use 10-20 mL/kg/hour, not exceeding 50 mL/kg over first 4 hours to minimize cerebral edema risk 2

Subsequent hours:

• Target correction of estimated fluid deficits (typically 6-9 liters in adults) within 24 hours 3
• Ensure serum osmolality change does not exceed 3 mOsm/kg H₂O per hour to prevent cerebral edema 3
• Monitor fluid input/output, blood pressure, and mental status hourly 1, 2

Insulin Therapy Protocol

Critical safety check: Never start insulin if serum potassium <3.3 mEq/L - this can cause fatal cardiac arrhythmias. 2

Once potassium ≥3.3 mEq/L:

• Start continuous IV regular insulin infusion at 0.1 units/kg/hour (typically 5-10 units/hour) without initial bolus 1, 2
• Continue insulin therapy until ketoacidosis resolves, regardless of glucose levels 1
• When serum glucose reaches 250 mg/dL, add dextrose 5% to IV fluids while continuing insulin infusion 1

Potassium Replacement Strategy

This is a critical pitfall area - total body potassium is severely depleted (3-5 mEq/kg deficit) despite potentially normal or elevated initial levels due to acidosis. 1, 3

Once renal function is confirmed and urine output is adequate:

• Add 20-30 mEq/L potassium to IV fluids (2/3 KCl and 1/3 KPO₄) when serum potassium falls below 5.5 mEq/L 1, 2
• Continue potassium replacement regardless of initial levels, as insulin therapy drives potassium intracellularly 2
• Monitor for inadequate replacement leading to arrhythmias 1

Monitoring Requirements

Hourly:

• Blood glucose 1
• Vital signs, mental status, fluid input/output 2

Every 2-4 hours until stable:

• Electrolytes, BUN, creatinine, osmolality 1, 3
• Venous pH and anion gap 1

Resolution Criteria (All Must Be Met)

• Blood glucose <200 mg/dL 1, 2
• Serum bicarbonate ≥15 mEq/L 1, 2
• Venous pH >7.3 1, 2
• Anion gap normalized (≤12 mEq/L) 2

Transition to Subcutaneous Insulin

Administer basal subcutaneous insulin 2-4 hours before discontinuing IV insulin to prevent rebound hyperglycemia. 2 This overlap period is essential - discontinuing IV insulin without prior subcutaneous administration is a common pitfall. 1

Special Considerations and Pitfalls

Bicarbonate therapy: Do not use routinely - it has not improved outcomes and may worsen hypokalemia and increase cerebral edema risk. 2, 4 Consider only if pH <6.9 or in peri-intubation period when pH <7.2 to prevent hemodynamic collapse. 4

Elderly or cardiac/renal compromise: Use more cautious fluid rates with closer hemodynamic monitoring to avoid volume overload. 1, 2

Cerebral edema risk factors: Avoid overly rapid correction of hyperglycemia and hyperosmolality, particularly in pediatric patients. 1, 5 Risk increases with severe acidosis, greater hypocapnia, higher BUN at presentation, and bicarbonate treatment. 5

Correct sodium for hyperglycemia: Add 1.6 mEq/L to measured sodium for each 100 mg/dL glucose above 100 mg/dL to assess true sodium status. 3