Management of Diabetic Ketoacidosis (DKA)
For critically ill and mentally obtunded patients with DKA, continuous intravenous insulin is the standard of care, combined with aggressive fluid resuscitation, electrolyte replacement, and identification of the precipitating cause. 1, 2
Initial Assessment and Diagnosis
Perform immediate laboratory evaluation including: 2, 3
- Plasma glucose, blood urea nitrogen, creatinine
- Serum ketones with calculated anion gap
- Electrolytes, osmolality
- Arterial blood gases
- Complete blood count
- Urinalysis with urine ketones
DKA is confirmed when all three criteria are present: 4
- Elevated blood glucose (or diabetes history)
- High urinary or blood ketoacids
- High anion gap metabolic acidosis
Identify and treat precipitating factors such as sepsis, myocardial infarction, stroke, or medication non-compliance. 1, 2
Fluid Resuscitation
Begin with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour (approximately 1-1.5 liters in average adults) to restore circulatory volume and tissue perfusion. 2, 3, 5
After initial resuscitation: 3
- Continue with 0.45% NaCl at 4-14 mL/kg/hour if corrected serum sodium is normal or elevated
- Use 0.9% NaCl if corrected serum sodium is low
- Monitor fluid input/output and hemodynamic status continuously
Common pitfall: Avoid excessive fluid administration in patients with cardiac dysfunction or pleural effusions, as this can worsen pulmonary edema. 5
Insulin Therapy
Administer continuous intravenous regular insulin at 0.1 U/kg/hour after confirming potassium >3.3 mEq/L and adequate renal function. 2, 5
Target glucose reduction of 50-75 mg/dL per hour. 5
When glucose reaches 200-250 mg/dL, add dextrose to IV fluids while continuing insulin infusion to prevent hypoglycemia and ensure complete ketone clearance. 3, 5
For mild to moderate uncomplicated DKA, subcutaneous rapid-acting insulin analogs may be used when combined with aggressive fluid management. 1, 2 However, this is not appropriate for severe DKA or critically ill patients.
Electrolyte Management
Potassium
Monitor potassium closely as total body potassium is depleted despite potentially normal or elevated initial levels due to acidosis. 2, 3
Once renal function is confirmed and serum potassium falls below 5.5 mEq/L, add 20-40 mEq/L potassium to the infusion (2/3 KCl and 1/3 KPO₄). 2, 3
Severe hypokalemia (<2.5 mEq/L) is associated with increased inpatient mortality. 2
Bicarbonate
Bicarbonate administration is generally not recommended, as multiple studies show it makes no difference in resolution of acidosis or time to discharge. 1, 2, 3 This applies even to severe acidosis with pH <7.00.
Other Electrolytes
Monitor and replace phosphate, magnesium, and calcium as needed. 2
Monitoring During Treatment
Check blood glucose every 1-2 hours until stable, then every 4 hours. 2, 5
Draw blood every 2-4 hours to assess: 2, 3, 5
- Serum electrolytes
- Glucose
- Blood urea nitrogen, creatinine
- Osmolality
- Venous pH
DKA resolution is confirmed when all of the following are met: 2, 3
- Glucose <200 mg/dL
- Serum bicarbonate ≥18 mEq/L
- Venous pH >7.3
- Anion gap ≤12 mEq/L
Transition from IV to Subcutaneous Insulin
Administer basal insulin 2-4 hours before stopping IV insulin to prevent recurrence of ketoacidosis and rebound hyperglycemia. 1, 2, 3, 5
Recent studies show that adding low-dose basal insulin analog during IV insulin infusion may prevent rebound hyperglycemia without increasing hypoglycemia risk. 2
Critical pitfall: Premature discontinuation of insulin before complete ketosis resolution leads to DKA recurrence. 2
Special Considerations
Euglycemic DKA
Recognize euglycemic DKA in patients on SGLT2 inhibitors, where glucose may be only mildly elevated despite significant ketoacidosis. 6, 7
Cardiac Compromise
In patients with cardiac dysfunction (e.g., Takotsubo cardiomyopathy), avoid insulin bolus and use slower infusion rates (0.1 U/kg/h without bolus). 5
Cerebral Edema
Avoid rapid correction of hyperglycemia and osmolality (not exceeding 3 mOsm/kg/h) to prevent cerebral edema, particularly in younger patients. 5
Pregnancy and Renal Disease
Management in these populations requires modified approaches, though data are limited to case series and expert opinion. 6, 7
Discharge Planning
Begin discharge planning at admission and update as needs change. 1, 2
Ensure patients have: 2
- Appropriate medications, supplies, and prescriptions
- Education on diabetes management, self-monitoring, and recognition of hyperglycemia/hypoglycemia
- Structured discharge communication including medication changes and follow-up needs
Schedule outpatient follow-up within 1-2 weeks if glycemic medications were changed, or within 1 month for all patients with hyperglycemia during hospitalization. 1