What is the treatment for diabetic ketoacidosis (DKA)?

Treatment of Diabetic Ketoacidosis

For critically ill patients with DKA, initiate aggressive fluid resuscitation with isotonic saline at 15-20 mL/kg/hour followed by continuous intravenous regular insulin at 0.1 units/kg/hour (after excluding hypokalemia), and continue insulin therapy until resolution of ketoacidosis regardless of glucose levels. 1

Initial Assessment and Stabilization

Upon presentation, obtain the following laboratory studies immediately 1, 2:

• Plasma glucose, serum ketones (β-hydroxybutyrate preferred), electrolytes, osmolality
• Blood urea nitrogen, creatinine, venous pH, anion gap
• Urinalysis with urine ketones
• Complete blood count with differential
• Electrocardiogram
• Arterial blood gases (initial only; venous pH sufficient for subsequent monitoring)
• Bacterial cultures (blood, urine, throat) if infection suspected 2

The diagnostic criteria are: metabolic acidosis (pH <7.3, bicarbonate <18 mEq/L, anion gap >10 mEq/L) with elevated ketones; hyperglycemia has been de-emphasized due to increasing euglycemic DKA. 3

Fluid Resuscitation Protocol

First Hour

Administer isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour to restore circulatory volume and tissue perfusion 4, 1. In severely dehydrated patients, this aggressive initial rate is critical for hemodynamic stabilization 4.

Subsequent Fluid Management

After initial volume expansion, continue fluid replacement at a rate calculated to replace the estimated deficit evenly over 24-48 hours 4. The induced change in serum osmolality should not exceed 3 mOsm/kg/hour 4.

When serum glucose reaches 250 mg/dL, switch to 5% dextrose with 0.45-0.75% NaCl while continuing insulin therapy to resolve ketosis. 1 This is essential because ketonemia takes longer to clear than hyperglycemia 4, 1.

Pediatric Considerations (≤20 years)

• Initial fluid: 0.9% NaCl at 10-20 mL/kg/hour for the first hour 4
• Do not exceed 50 mL/kg over the first 4 hours to minimize cerebral edema risk 4
• Continue at 1.5 times 24-hour maintenance requirements 4

Insulin Therapy

Adult Protocol

After confirming serum potassium ≥3.3 mEq/L, administer an intravenous bolus of regular insulin at 0.15 units/kg body weight, followed immediately by continuous infusion at 0.1 units/kg/hour (typically 5-7 units/hour). 4, 1

This regimen decreases plasma glucose at 50-75 mg/dL/hour 4. If glucose does not fall by 50 mg/dL in the first hour and hydration is adequate, double the insulin infusion rate hourly until achieving steady decline 4, 1.

Pediatric Protocol

Do NOT give an initial insulin bolus in children. 1 Start directly with continuous infusion at 0.1 units/kg/hour 1.

Mild DKA Alternative

For uncomplicated mild DKA, subcutaneous rapid-acting insulin analogs combined with aggressive fluid management may be used in emergency departments or step-down units 4, 1. This approach is safer and more cost-effective than ICU admission for selected patients 4.

Electrolyte Management

Potassium Replacement

Insulin administration drives potassium intracellularly, causing potentially dangerous hypokalemia. 1, 5

• Do not start insulin if K+ <3.3 mEq/L 4, 1
• Once renal function confirmed and K+ known, add 20-40 mEq/L potassium to IV fluids (2/3 KCl and 1/3 KPO₄) 4, 1
• Target serum potassium 4-5 mmol/L throughout treatment 1
• Monitor potassium every 2-4 hours 1, 2

Sodium Correction

Correct measured sodium for hyperglycemia: for each 100 mg/dL glucose above 100 mg/dL, add 1.6 mEq to the sodium value 4.

Bicarbonate

Bicarbonate administration is generally not recommended, as studies show no difference in acidosis resolution or time to discharge. 4

Monitoring During Treatment

Draw blood every 2-4 hours for 1, 2:

• Serum electrolytes and glucose
• Blood urea nitrogen and creatinine
• Venous pH (adequate for tracking acidosis; typically 0.03 units lower than arterial pH) 6
• Anion gap (confirms ketoacid clearance) 6
• Serum osmolality

Direct measurement of β-hydroxybutyrate in blood is the preferred method for monitoring DKA resolution. 1, 6 The nitroprusside method only measures acetoacetic acid and acetone, not β-hydroxybutyrate, and should not guide treatment 6.

Resolution Criteria

DKA is resolved when ALL of the following are met: 1, 6

• Glucose <200 mg/dL
• Serum bicarbonate ≥18 mEq/L
• Venous pH >7.3
• Anion gap ≤12 mEq/L

Continue insulin therapy until these criteria are met, even if glucose normalizes, because ketonemia clears more slowly than hyperglycemia. 1, 6 Target glucose 150-200 mg/dL during treatment by adding dextrose to IV fluids while maintaining insulin infusion 1.

Transition to Subcutaneous Insulin

Critical Timing

Administer basal insulin (glargine or detemir) 2-4 hours BEFORE stopping the IV insulin infusion. 4, 1, 2 This prevents recurrence of ketoacidosis and rebound hyperglycemia 4, 1.

Premature termination of IV insulin without prior basal insulin administration is the most common error leading to DKA recurrence. 2, 5

Post-Resolution Regimen

Once the patient can eat, initiate a multiple-dose subcutaneous insulin schedule combining short/rapid-acting and intermediate/long-acting insulin 1, 2. Continue IV insulin for 1-2 hours after starting subcutaneous insulin to ensure adequate plasma insulin levels 6.

If the patient remains NPO after DKA resolution, continue IV insulin and supplement with subcutaneous regular insulin every 4 hours as needed (5-unit increments for every 50 mg/dL glucose above 150 mg/dL, up to 20 units for glucose 300 mg/dL) 6.

Common Pitfalls to Avoid

• Stopping IV insulin when glucose falls below 250 mg/dL without adding dextrose to fluids—this causes persistent ketoacidosis 1, 6
• Inadequate potassium monitoring and replacement—insulin therapy rapidly lowers serum potassium 1
• Discontinuing IV insulin without prior basal insulin administration—leads to rebound hyperglycemia and ketoacidosis recurrence 2, 5
• Using nitroprusside method for ketone monitoring—only β-hydroxybutyrate accurately reflects DKA resolution 6
• Overly rapid fluid administration in children—increases cerebral edema risk 4

Identifying and Treating Precipitating Causes

Aggressively search for and treat underlying triggers 4, 1:

• Infection (most common): obtain cultures and initiate appropriate antibiotics 2
• Myocardial infarction: obtain troponin and ECG 3
• Stroke: perform neurological examination
• Medication non-adherence or insulin pump failure
• New-onset diabetes

Special Considerations

Euglycemic DKA

In patients with glucose <250 mg/dL but meeting other DKA criteria (increasingly common with SGLT-2 inhibitor use), start D5 with 0.9% NaCl alongside insulin therapy from the beginning 1, 3.

Cardiac or Renal Compromise

Monitor serum osmolality and perform frequent cardiac, renal, and mental status assessments during fluid resuscitation to avoid iatrogenic fluid overload 4.

Discharge Planning

Begin structured discharge planning at admission 4, 2. Ensure medication reconciliation, patient education on insulin administration and sick day management, and schedule follow-up appointments before discharge to reduce readmission rates 4, 2.