Diabetic Ketoacidosis (DKA) Management Protocol

Diagnostic Criteria

DKA is diagnosed when all three criteria are met: blood glucose >250 mg/dL, venous pH <7.3, serum bicarbonate <15 mEq/L, and moderate ketonuria or ketonemia. 1, 2

Severity Classification

Mild DKA: pH 7.25-7.30, bicarbonate 15-18 mEq/L, alert mental status 3, 2
Moderate DKA: pH 7.00-7.24, bicarbonate 10-15 mEq/L, drowsy mental status 3, 2
Severe DKA: pH <7.00, bicarbonate <10 mEq/L, stupor/coma 3, 2

Initial Laboratory Assessment

Obtain immediately upon presentation 1, 2:

Arterial or venous blood gas (venous pH is 0.03 units lower than arterial and adequate for monitoring) 2
Complete metabolic panel with calculated anion gap: [Na⁺] - ([Cl⁻] + [HCO₃⁻]) should be >10-12 mEq/L 3, 2
Direct blood β-hydroxybutyrate measurement (NOT nitroprusside-based urine ketones) 1, 2
Complete blood count with differential 1
Serum osmolality: 2[measured Na (mEq/L)] + glucose (mg/dL)/18 3
Urinalysis 1
Electrocardiogram 3, 1
Bacterial cultures (blood, urine, throat) if infection suspected 2

Critical pitfall: Never rely on urine ketones or nitroprusside methods—they only measure acetoacetate and acetone, completely missing β-hydroxybutyrate (the predominant ketoacid), and can falsely suggest worsening ketosis during treatment as β-hydroxybutyrate converts to acetoacetate. 1, 2

Fluid Resuscitation

Begin immediately with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour to restore intravascular volume and renal perfusion. 3, 1, 4

Subsequent Fluid Management

After initial bolus 3, 1:

If corrected serum sodium is normal or elevated: Use 0.45% NaCl at 4-14 mL/kg/hour
If corrected serum sodium is low: Continue 0.9% NaCl at 4-14 mL/kg/hour
Correct sodium for hyperglycemia: Add 1.6 mEq/L for every 100 mg/dL glucose above 100 mg/dL 3, 2
Target total fluid replacement to correct estimated deficits (typically 6-9 liters) within 24 hours 1, 2

Monitor closely for fluid overload, particularly in patients with renal or cardiac compromise. 1, 2

Insulin Therapy

Start continuous IV regular insulin at 0.1 units/kg/hour WITHOUT an initial bolus after confirming potassium >3.3 mEq/L. 1, 2, 4

Insulin Adjustment Algorithm

If glucose does not fall by 50 mg/dL in the first hour, double the insulin infusion rate hourly until achieving a steady decline of 50-75 mg/dL per hour 2
When glucose reaches 250 mg/dL, add dextrose 5-10% to IV fluids while continuing insulin infusion 1, 4
Never stop insulin based on glucose levels alone—continue until ketoacidosis resolves 1, 4

Critical principle: The therapeutic target is ketone clearance, not glucose normalization. Insulin must continue until metabolic acidosis resolves, regardless of glucose levels. 4

Special Consideration: Euglycemic DKA

If glucose is <250 mg/dL or normal at presentation but DKA criteria are met (pH <7.3, bicarbonate <15 mEq/L, elevated ketones) 4:

Immediately add dextrose 5-10% to IV fluids at presentation
Start insulin at 0.1 units/kg/hour as usual
Continue insulin until acidosis resolves, not until glucose normalizes

Potassium Management

Total body potassium is severely depleted (3-5 mEq/kg deficit) despite potentially normal or elevated initial serum levels due to acidosis. 3, 1, 2

Potassium Replacement Protocol

If initial K⁺ <3.3 mEq/L: Delay insulin therapy and aggressively replace potassium first to prevent fatal cardiac arrhythmias 2
If K⁺ >5.5 mEq/L: Do not add potassium to IV fluids initially; recheck in 2 hours 1, 2
If K⁺ 3.3-5.5 mEq/L: Add 20-30 mEq/L potassium to IV fluids (2/3 KCl and 1/3 KPO₄) once adequate urine output confirmed 3, 1, 2
Target serum potassium 4-5 mEq/L throughout treatment 2

Critical pitfall: Inadequate potassium replacement is a leading cause of arrhythmias and death in DKA. 1

Monitoring During Treatment

Frequency of Laboratory Checks

Blood glucose: Every 1 hour 1
Electrolytes, BUN, creatinine, osmolality: Every 2-4 hours until stable 3, 1, 2
Venous pH and anion gap: Every 2-4 hours to monitor acidosis resolution 1, 2
β-hydroxybutyrate: Every 2-4 hours (ketonemia takes longer to clear than hyperglycemia) 1, 2

After initial diagnosis, venous pH and anion gap adequately monitor acidosis resolution without requiring repeated arterial blood gases. 2

Resolution Criteria

DKA is resolved when ALL of the following are met 1, 2, 4:

Blood glucose <200 mg/dL
Serum bicarbonate ≥15-18 mEq/L
Venous pH >7.3
Anion gap ≤12 mEq/L (normalized)

Transition to Subcutaneous Insulin

Administer basal subcutaneous insulin (e.g., glargine) 2-4 hours BEFORE stopping IV insulin to prevent rebound hyperglycemia and ketoacidosis. 1, 4

Critical pitfall: Discontinuing IV insulin without overlapping subcutaneous basal insulin leads to recurrent DKA. 1

Additional Electrolyte Considerations

Typical total body deficits in DKA 3, 1:

Phosphate: 5-7 mmol/kg (included as 1/3 of potassium replacement as KPO₄)
Magnesium: 1-2 mEq/kg (replace if symptomatic or <1.8 mg/dL)
Calcium: 1-2 mEq/kg (monitor and replace as needed)

Bicarbonate Therapy

Bicarbonate therapy is NOT recommended for DKA management except when pH <6.9, due to risks of worsening ketosis, hypokalemia, and cerebral edema. 2, 5

Consider bicarbonate only if 5:

pH <6.9, OR
pH <7.2 with serum bicarbonate <10 mEq/L pre/post-intubation to prevent hemodynamic collapse

Cerebral Edema Prevention

Cerebral edema is the most dire complication of DKA, occurring more commonly in children but also in adults with severe DKA. 6, 7, 5

Risk Factors and Prevention

Avoid overly rapid correction of hyperglycemia and hyperosmolality 1, 5
Avoid bicarbonate therapy (increases cerebral edema risk) 6, 5
Monitor for signs: headache, altered mental status, bradycardia, hypertension 6
Severity of acidosis, greater hypocapnia, higher BUN at presentation increase risk 6

Precipitating Factors to Address

Identify and treat underlying causes to prevent recurrence 1, 8:

Infections (most common precipitant)
Insulin omission or nonadherence
New diagnosis of diabetes
SGLT2 inhibitor use (can cause euglycemic DKA)
Myocardial infarction, stroke, pancreatitis
Medications (corticosteroids, antipsychotics)

Common Pitfalls Summary

Stopping insulin when glucose normalizes before acidosis resolves 1, 4
Inadequate potassium replacement leading to arrhythmias 1, 2
Using urine ketones instead of blood β-hydroxybutyrate for monitoring 1, 2
Not overlapping IV insulin with subcutaneous basal insulin during transition 1, 4
Overly aggressive fluid resuscitation causing cerebral edema 1, 5
Starting insulin before confirming potassium >3.3 mEq/L 2
Failing to identify and treat precipitating cause 2, 8

What is the protocol for managing Diabetic Ketoacidosis (DKA)?

Help us tailor your experience