Management of Diabetic Ketoacidosis (DKA)
Begin immediate aggressive fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour in the first hour, followed by continuous intravenous insulin therapy once potassium is >3.3 mEq/L, while closely monitoring electrolytes and avoiding premature discontinuation of insulin before complete resolution of ketoacidosis. 1
Initial Diagnostic Confirmation
Before initiating treatment, confirm DKA diagnosis using the "DKA triad":
- 'D': Elevated blood glucose (typically ≥250 mg/dL) or family history of diabetes 2
- 'K': Presence of high urinary or blood ketoacids (β-hydroxybutyrate is preferred method) 1, 2
- 'A': High anion gap metabolic acidosis (pH <7.3, bicarbonate <18 mEq/L) 1, 2
Obtain comprehensive laboratory assessment including serum glucose, electrolytes with calculated anion gap, blood urea nitrogen, creatinine, pH, serum ketones (preferably β-hydroxybutyrate), osmolality, urinalysis, and complete blood count 1, 3. Direct measurement of β-hydroxybutyrate in blood is the preferred monitoring method over urine ketones 1.
Fluid Resuscitation (First Priority)
Start with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour to restore circulatory volume and tissue perfusion 1, 3. This aggressive initial fluid management is critical for reversing dehydration and improving insulin sensitivity 1.
After the initial hour, continue fluid replacement to correct dehydration, which is a key component of DKA management 1. Balanced electrolyte solutions have shown faster DKA resolution in some studies, though isotonic saline remains the standard 4.
Critical pitfall to avoid: Inadequate fluid resuscitation can worsen DKA, while excessive fluid administration (especially in patients with cardiac dysfunction or pleural effusions) can cause pulmonary edema 1, 3.
Insulin Therapy (Second Priority)
When to Start Insulin
Do not start insulin until:
Insulin Dosing
For severe DKA requiring ICU care: Administer continuous intravenous regular insulin at 0.1 U/kg/hour without initial bolus (especially if cardiac compromise is present) 3. Target gradual reduction in blood glucose by 50-75 mg/dL/hour 3.
For mild DKA in stable patients: Subcutaneous rapid-acting insulin analogs combined with aggressive fluid management can be as effective as intravenous insulin 1. British guidelines suggest using subcutaneous insulin glargine along with continuous regular IV insulin, which has shown faster DKA resolution and shorter hospital stays 4.
Critical Insulin Management Points
When blood glucose reaches 200-250 mg/dL, add dextrose to IV fluids while continuing insulin infusion 1, 3. This is essential because ketosis takes longer to clear than hyperglycemia 1.
The most common cause of persistent or worsening ketoacidosis is interruption of insulin infusion when glucose levels fall 1. Continue insulin therapy until complete resolution of ketoacidosis: pH >7.3, serum bicarbonate ≥18 mEq/L, and anion gap ≤12 mEq/L 1.
Electrolyte Management
Potassium Replacement
Monitor potassium levels closely, as insulin administration drives potassium intracellularly and can cause life-threatening hypokalemia 1.
- Ensure adequate potassium replacement to maintain serum K+ between 4-5 mmol/L 1
- Begin potassium replacement when levels fall below 5.5 mEq/L 3
- If initial potassium is <3.3 mEq/L, delay insulin and aggressively replace potassium first 1
Other Electrolytes
DKA frequently involves hypophosphatemia and hypomagnesemia requiring regular monitoring 4. However, routine phosphate replacement remains controversial 5.
Bicarbonate Administration
Bicarbonate administration is generally NOT recommended for DKA patients 1. It can worsen ketosis, cause hypokalemia, and increase risk of cerebral edema 4.
Exception: Consider IV sodium bicarbonate only if serum pH falls below 6.9, or when pH <7.2 and/or bicarbonate <10 mEq/L pre- and post-intubation to prevent hemodynamic collapse 4.
Monitoring During Treatment
Draw blood every 2-4 hours to determine serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH (typically 0.03 units lower than arterial pH) 1.
Check blood glucose every 1-2 hours until stable, then every 4 hours 3. Follow venous pH and anion gap to monitor resolution of acidosis 1.
Monitor fluid input/output, hemodynamic parameters, and clinical examination continuously 3.
Identifying and Treating Precipitating Factors
Immediately identify and treat precipitating factors such as infection, myocardial infarction, stroke, medication non-adherence, or new diagnosis of diabetes 1, 6.
Special consideration: Maintain high suspicion for DKA in patients on SGLT2 inhibitors (occurs at 0.6-4.9 events per 1,000 patient-years) and pregnant patients (even with normal or mildly elevated glucose) 7, 6.
Preventing Cerebral Edema
Avoid rapid correction of hyperglycemia and osmolality (not exceeding 3 mOsm/kg/h) to prevent cerebral edema, a rare but potentially fatal complication 3, 4. This is especially critical in younger patients 3.
Watch for signs of cerebral edema including mental status changes, severe headache, or seizures 3.
Transition to Subcutaneous Insulin
Once DKA resolves (glucose <200 mg/dL, bicarbonate ≥18 mEq/L, pH >7.3, anion gap ≤12 mEq/L), transition to subcutaneous insulin 1, 3.
Critical timing: Administer basal insulin 2-4 hours BEFORE stopping IV insulin to prevent recurrence of ketoacidosis 1, 3. Start a multiple-dose schedule using combination of short/rapid-acting and intermediate/long-acting insulin when the patient is able to eat 1.
Airway Management in Critically Ill Patients
For impending respiratory failure, do NOT use BiPAP due to aspiration risks 4. Instead, proceed with intubation and mechanical ventilation, with careful monitoring and management of acid-base and fluid status 4.
Provide supplemental oxygen to maintain oxygen saturation >92% 3. Position the patient upright if hemodynamically stable to improve lung expansion 3.
Nutrition
Initiate early oral nutrition once the patient is able to eat, as this has been shown to reduce ICU and overall hospital length of stay 4.
Disposition and Prevention
Develop a structured discharge plan including appropriate insulin regimen choice and dosing, patient education on adherence, self-care during illness, and improved access to medical providers 1, 6. Future episodes can be reduced through education programs and extended availability of phone services or telemedicine 6.