What is the management of diabetic ketoacidosis (DKA)?

Management of Diabetic Ketoacidosis (DKA)

Begin immediate aggressive fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour, followed by continuous intravenous insulin at 0.1 units/kg/hour, and continue insulin infusion until complete resolution of ketoacidosis regardless of glucose levels. 1, 2, 3

Diagnostic Criteria

• DKA is diagnosed by blood glucose >250 mg/dL, arterial pH <7.3, serum bicarbonate <15 mEq/L, and presence of ketonemia or ketonuria. 1, 2
• Obtain immediate laboratory evaluation including plasma glucose, blood urea nitrogen/creatinine, serum ketones, electrolytes with calculated anion gap, osmolality, urinalysis, arterial blood gases, complete blood count with differential, and electrocardiogram. 1, 2
• Direct measurement of β-hydroxybutyrate in blood is strongly preferred over the nitroprusside method, which only detects acetoacetic acid and acetone, missing the predominant ketone body in DKA. 4, 2, 3
• Obtain bacterial cultures (urine, blood, throat) and initiate appropriate antibiotics if infection is suspected as a precipitating factor. 1, 2

Initial Fluid Resuscitation

• Start with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 L in average adult) during the first hour to expand intravascular volume and restore renal perfusion. 1, 2, 3
• After the first hour, if corrected serum sodium is normal or elevated, switch to 0.45% NaCl at 4-14 mL/kg/hour; if corrected serum sodium is low, continue 0.9% NaCl at similar rate. 1, 3
• Correct serum sodium for hyperglycemia by adding 1.6 mEq to sodium value for each 100 mg/dL glucose above 100 mg/dL. 1
• When serum glucose reaches 200-250 mg/dL, add 5% dextrose with 0.45-0.75% NaCl to prevent hypoglycemia while continuing insulin therapy to clear ketosis. 4, 2, 3

Insulin Therapy

• Initiate continuous intravenous regular insulin infusion at 0.1 units/kg/hour without an initial bolus (preferred method for moderate to severe DKA). 4, 2, 3
• If plasma glucose does not fall by 50 mg/dL from initial value in the first hour, verify adequate hydration status, then double the insulin infusion rate hourly until achieving steady glucose decline of 50-75 mg/hour. 2, 3
• Never interrupt insulin infusion when glucose levels fall—this is a critical error that perpetuates ketoacidosis; instead, add dextrose-containing fluids to maintain glucose between 150-200 mg/dL. 4, 2, 3
• Continue insulin infusion until complete resolution of ketoacidosis (pH >7.3, serum bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L) regardless of glucose levels. 4, 2, 3

Electrolyte Management

• Once renal function is assured and serum potassium is <5.3 mEq/L, include 20-30 mEq/L potassium (2/3 KCl and 1/3 KPO₄) in the infusion. 1, 2, 3
• Monitor potassium levels closely every 2-4 hours, as insulin therapy and correction of acidosis cause significant hypokalemia; maintain serum potassium between 4-5 mmol/L. 4, 2, 3
• Bicarbonate administration is generally not recommended for DKA patients with pH >6.9-7.0, as it provides no benefit in resolution of acidosis or time to discharge and may worsen hypokalemia and increase risk of cerebral edema. 1, 2, 3, 5
• Consider bicarbonate only if pH falls below 6.9, or when pH <7.2 with serum bicarbonate <10 mEq/L in the peri-intubation period to prevent hemodynamic collapse. 6

Monitoring During Treatment

• Draw blood every 2-4 hours to measure serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH. 2, 3
• Check blood glucose every 1-2 hours throughout treatment. 4
• Follow venous pH (typically 0.03 units lower than arterial pH) and anion gap to monitor resolution of acidosis, as these are more reliable than glucose levels alone. 4, 2
• Remember that ketonemia typically takes longer to clear than hyperglycemia, so do not prematurely discontinue insulin based solely on glucose normalization. 3

Resolution Criteria and Transition

• DKA is resolved when all of the following are met: glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH >7.3, and anion gap ≤12 mEq/L. 2, 3
• When transitioning to subcutaneous insulin, administer basal insulin 2-4 hours before stopping intravenous insulin to prevent recurrence of ketoacidosis and rebound hyperglycemia. 1, 4, 2
• Once patient can eat, initiate multiple-dose insulin schedule using combination of short/rapid-acting and intermediate/long-acting insulin. 2, 3

Special Considerations

• For uncomplicated mild to moderate DKA, subcutaneous rapid-acting insulin analogs combined with aggressive fluid management may be used in emergency department or step-down units, which can be safer and more cost-effective than intravenous insulin. 1
• In euglycemic DKA (increasingly common with SGLT2 inhibitor use), add dextrose-containing fluids earlier in treatment while continuing insulin therapy, as insulin is still required to clear ketosis despite normal glucose levels. 4
• Consider thromboprophylaxis with enoxaparin due to the hypercoagulable state associated with DKA. 3
• Identify and treat precipitating factors including infection, myocardial infarction, stroke, medication non-adherence, or new-onset diabetes. 2, 3

Critical Pitfalls to Avoid

• Premature termination of insulin therapy before complete resolution of ketosis (all resolution criteria must be met, not just glucose normalization). 4, 2, 3
• Interrupting insulin infusion when glucose falls below 250 mg/dL without adding dextrose—this is the most common cause of persistent or worsening ketoacidosis. 4, 2, 3
• Relying solely on urine ketones or nitroprusside method for monitoring, which misses β-hydroxybutyrate. 4, 2, 3
• Inadequate potassium monitoring and replacement, leading to life-threatening hypokalemia during treatment. 4, 2, 3
• Overly aggressive fluid resuscitation in patients with cardiac or renal compromise without appropriate monitoring. 1
• Stopping intravenous insulin and immediately switching to subcutaneous insulin without the 2-4 hour overlap period. 1, 4, 2