Management of Diabetic Ketoacidosis (DKA)
Immediate Priorities
Begin aggressive fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour, followed by continuous intravenous insulin therapy once potassium is >3.3 mEq/L, while simultaneously identifying and treating the precipitating cause. 1
Initial Assessment and Laboratory Evaluation
Obtain the following labs immediately to confirm diagnosis and guide management: 1
- Plasma glucose (though hyperglycemia may be absent in euglycemic DKA)
- Arterial blood gases to assess pH and degree of acidosis
- Serum ketones (preferred over urine ketones)
- Electrolytes with calculated anion gap (DKA confirmed when anion gap >10 mEq/L)
- Serum bicarbonate (DKA when <18 mEq/L)
- Blood urea nitrogen, creatinine, and osmolality
- Complete blood count to evaluate for infection
- Urinalysis
- Electrocardiography to assess for cardiac complications and potassium abnormalities 2
DKA is diagnosed by the triad: metabolic acidosis (pH <7.3, bicarbonate <18 mEq/L, anion gap >10 mEq/L), elevated ketones, and typically (but not always) hyperglycemia >250 mg/dL. 2, 3
Fluid Resuscitation Protocol
Hour 1: Administer isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour to restore circulatory volume and tissue perfusion. 1
Subsequent hours: Continue fluid replacement based on hemodynamic status, serum electrolyte levels, and urine output, correcting estimated deficits within 24 hours. 1
Critical caveat: Monitor fluid input/output and clinical examination continuously. In patients with cardiac dysfunction or pleural effusions, avoid excessive fluid administration which may worsen pulmonary edema. 4
Insulin Therapy
For critically ill or mentally obtunded patients: Continuous intravenous regular insulin is the standard of care. 1
- Do NOT start insulin until potassium is >3.3 mEq/L to avoid life-threatening hypokalemia 1
- Standard dosing: 0.1 units/kg/hour continuous IV infusion (bolus may be omitted in patients with cardiac compromise) 4, 5
- Target glucose reduction: 50-75 mg/dL per hour 4
For mild-to-moderate uncomplicated DKA: Subcutaneous rapid-acting insulin analogs may be used when combined with aggressive fluid management. 1
When glucose reaches 250 mg/dL: Add dextrose to IV fluids while continuing insulin infusion until ketoacidosis resolves (do NOT stop insulin when glucose normalizes). 4
Electrolyte Management
Potassium Replacement
Monitor potassium every 2-4 hours. Total body potassium is depleted despite potentially normal or elevated initial levels due to acidosis-induced extracellular shift. 1
- When potassium <5.5 mEq/L: Add 20-40 mEq/L potassium to IV fluids (assuming adequate urine output) 1
- Severe hypokalemia (<2.5 mEq/L) is associated with increased inpatient mortality and cardiac arrhythmias 1
Other Electrolytes
Monitor and replace phosphate, magnesium, and calcium as needed. 1
Bicarbonate
Bicarbonate administration is NOT recommended. Studies demonstrate it makes no difference in resolution of acidosis or time to discharge. 1
Monitoring During Treatment
Draw blood every 2-4 hours to assess: 1
- Serum electrolytes
- Glucose
- Blood urea nitrogen and creatinine
- Osmolality
- Venous pH
Monitor blood glucose every 1-2 hours until stable, then every 4 hours. 4
Watch for cerebral edema, particularly in younger patients—avoid rapid correction of hyperglycemia and osmolality (not exceeding 3 mOsm/kg/h). 4
Criteria for Resolution
Treatment success is indicated by ALL of the following: 1
- pH >7.3
- Serum bicarbonate ≥18 mEq/L
- Anion gap ≤12 mEq/L
- Improvement in clinical symptoms
Transition from IV to Subcutaneous Insulin
Administer basal insulin (long-acting) 2-4 hours BEFORE stopping IV insulin to prevent rebound hyperglycemia and recurrence of ketoacidosis. 1, 6
Ensure the following before transitioning: 1
- Stable glucose measurements for at least 4-6 hours consecutively
- Normal anion gap and resolution of acidosis
- Patient able to eat
Identifying and Treating Precipitating Causes
The most common triggers include: 7, 8
- Infection (most common)
- Myocardial infarction or stroke
- New diagnosis of diabetes
- Nonadherence to insulin therapy
- Sodium-glucose cotransporter-2 (SGLT-2) inhibitors (modestly increase DKA risk, including euglycemic DKA) 2
Failure to identify and treat the underlying cause leads to treatment failure. 1
Common Pitfalls to Avoid
- Premature discontinuation of IV insulin before complete resolution of ketosis leads to DKA recurrence 1, 6
- Starting insulin before potassium >3.3 mEq/L risks fatal cardiac arrhythmias 1
- Inadequate fluid resuscitation delays recovery and worsens outcomes 1
- Stopping insulin when glucose normalizes rather than waiting for ketoacidosis resolution 4
- Insufficient timing or dosing of subcutaneous insulin before stopping IV insulin 6
- Excessive fluid administration in patients with cardiac dysfunction 4
Discharge Planning
Begin discharge planning at admission and update as patient needs change: 1
- Provide structured discharge communication including medication changes, pending tests, and follow-up needs 1
- Educate patients on diabetes management, self-monitoring of blood glucose, home glucose goals, recognition and treatment of hyperglycemia/hypoglycemia, and when to call their provider 1
- Ensure patients have appropriate medications, supplies, and prescriptions at discharge to avoid dangerous gaps in care 1
- Schedule follow-up appointments prior to discharge to increase attendance likelihood 1