What is the management for diabetic ketoacidosis (DKA)?

Management of Diabetic Ketoacidosis

Begin immediate fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour for the first hour, followed by continuous IV regular insulin at 0.1 units/kg/hour without an initial bolus, while closely monitoring and replacing potassium to prevent life-threatening hypokalemia. 1, 2

Initial Assessment and Diagnosis

Obtain the following laboratory tests immediately upon presentation 1, 2:

• Plasma glucose, arterial blood gases, serum ketones (preferably β-hydroxybutyrate)
• Complete metabolic panel with calculated anion gap and osmolality
• Blood urea nitrogen, creatinine, complete blood count
• Urinalysis with urine ketones
• Electrocardiogram
• Blood and urine cultures if infection suspected 2

Diagnostic criteria for DKA: plasma glucose >250 mg/dL, arterial pH <7.30, serum bicarbonate <18 mEq/L, and positive serum/urine ketones 3, 1. Note that euglycemic DKA (glucose <250 mg/dL) is increasingly recognized, particularly in patients on SGLT2 inhibitors 1, 4.

Fluid Resuscitation

First hour: Administer isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 liters in average adults) to restore intravascular volume and renal perfusion 3, 1, 2.

Subsequent fluid management depends on corrected serum sodium 3:

• If corrected sodium is normal or elevated: switch to 0.45% NaCl at 4-14 mL/kg/hour
• If corrected sodium is low: continue 0.9% NaCl at 4-14 mL/kg/hour
• Total fluid goal: approximately 1.5-2 times the 24-hour maintenance requirements 1, 2

A recent 2024 study suggests balanced crystalloids like Sterofundin may be superior to normal saline, showing faster DKA resolution (13.8 vs 18.1 hours) and reduced hyperchloremic acidosis, though this requires further validation 5.

Insulin Therapy

Start continuous IV regular insulin infusion at 0.1 units/kg/hour WITHOUT an initial bolus 1, 2. The bolus approach has fallen out of favor in recent guidelines.

If glucose does not fall by 50 mg/dL in the first hour: double the insulin infusion rate hourly until steady glucose decline is achieved 1.

Target glucose reduction: 50-75 mg/dL per hour 1.

Critical: When glucose reaches 200-250 mg/dL, add 5% dextrose to IV fluids but DO NOT stop insulin 4. Continue insulin infusion until ketoacidosis resolves, not just until glucose normalizes. This is a common pitfall that leads to persistent ketosis 4.

Electrolyte Management

Potassium Replacement

This is the most dangerous electrolyte abnormality in DKA management 1, 2.

• Before starting insulin: ensure potassium is >3.3 mEq/L; if lower, give potassium first before any insulin 1
• Once renal function confirmed and K+ <5.3 mEq/L: add 20-30 mEq/L potassium to IV fluids (2/3 KCl and 1/3 KPO₄) 3, 1, 4
• Target range: maintain serum potassium between 4-5 mEq/L throughout treatment 4
• Mechanism: insulin drives potassium intracellularly, and correction of acidosis further lowers serum potassium 1, 2

Bicarbonate Administration

Bicarbonate is NOT routinely recommended for pH >6.9 4, 6. The FDA label indicates bicarbonate for severe metabolic acidosis, but current guidelines reserve this only for pH <6.9 due to risks of paradoxical CNS acidosis and hypokalemia 6.

Phosphate

Included as part of potassium replacement (1/3 as KPO₄), but routine aggressive phosphate replacement is not recommended 3.

Monitoring During Treatment

Blood glucose: every 1-2 hours 1, 4

Comprehensive metabolic panel (electrolytes, glucose, BUN, creatinine, osmolality) and venous pH: every 2-4 hours 1, 4, 2

Follow venous pH and anion gap to monitor resolution of acidosis rather than relying solely on glucose 1, 4.

Resolution Criteria and Transition to Subcutaneous Insulin

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

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

Critical transition step: Administer basal insulin (glargine or detemir) 2-4 hours BEFORE stopping IV insulin to prevent rebound hyperglycemia and recurrent ketoacidosis 1, 4, 2. This is the most common error leading to DKA recurrence 2.

Consider adding a low dose of basal insulin analog during IV insulin infusion to further prevent rebound 1, 4.

Identification and Treatment of Precipitating Causes

Common precipitating factors include 7, 8:

• Infections (most common)
• New diagnosis of diabetes
• Insulin non-adherence
• SGLT2 inhibitor use

For patients on SGLT2 inhibitors: discontinue 3-4 days before surgery and monitor for euglycemic DKA 1. These medications modestly increase DKA risk and can present with normal or only mildly elevated glucose 1, 8.

Obtain chest X-ray and cultures as clinically indicated 2. Administer appropriate antibiotics if infection identified 2.

Common Pitfalls to Avoid

• Stopping IV insulin when glucose normalizes before ketoacidosis resolves—continue insulin and add dextrose instead 4
• Failing to administer basal insulin 2-4 hours before stopping IV insulin—this causes DKA recurrence 1, 2
• Starting insulin before ensuring adequate potassium levels (>3.3 mEq/L)—this can cause fatal arrhythmias 1
• Inadequate fluid resuscitation in the first hour—this delays resolution 1, 2
• Using nitroprusside method alone for ketone measurement—this misses β-hydroxybutyrate, the predominant ketone body 4
• Premature transition to subcutaneous insulin before all resolution criteria are met 4