What is the immediate treatment for a patient presenting with Diabetic Ketoacidosis (DKA)?

Immediate Treatment of Diabetic Ketoacidosis

Begin aggressive fluid resuscitation with isotonic saline at 15-20 mL/kg/hour in the first hour, followed by continuous intravenous insulin infusion at 0.1 units/kg/hour once potassium is ≥3.3 mEq/L, while simultaneously replacing electrolytes and treating any underlying precipitating cause. 1, 2, 3

Initial Assessment and Stabilization

Diagnostic Confirmation

• Confirm DKA diagnosis with: blood glucose >250 mg/dL, arterial pH <7.3, serum bicarbonate <15 mEq/L, and presence of ketonemia or ketonuria 3
• Obtain immediate laboratory evaluation including plasma glucose, electrolytes with calculated anion gap, serum ketones, arterial blood gases, complete blood count, and electrocardiogram 2, 3
• Identify precipitating factors: infection (obtain bacterial cultures of urine, blood, throat if suspected), myocardial infarction, stroke, insulin omission, or SGLT2 inhibitor use 2, 3

Fluid Resuscitation Protocol

• 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 1, 2, 3
• Subsequent fluid choice depends on hydration status, serum electrolyte levels, and urine output 3
• When serum glucose reaches 250 mg/dL, switch to 5% dextrose with 0.45-0.75% NaCl to prevent hypoglycemia while continuing insulin therapy 3
• Total fluid replacement should correct estimated deficits within 24 hours 3

Insulin Therapy

Critical Pre-Insulin Check

• DO NOT start insulin if potassium is <3.3 mEq/L—this is an absolute contraindication that can cause life-threatening cardiac arrhythmias and death 2, 3
• If K+ <3.3 mEq/L, delay insulin and aggressively replace potassium until levels reach ≥3.3 mEq/L 2, 3
• Obtain electrocardiogram to assess cardiac effects of hypokalemia 2

Insulin Initiation and Dosing

• Once K+ ≥3.3 mEq/L, start IV bolus of regular insulin at 0.1 units/kg, followed by continuous infusion at 0.1 units/kg/hour 2, 3
• Target glucose decline of 50-75 mg/dL/hour 2, 3
• If glucose does not fall by 50 mg/dL in the first hour, check hydration status; if acceptable, double the insulin infusion rate every hour until steady decline achieved 3
• Continue insulin infusion until complete resolution of ketoacidosis (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L) regardless of glucose levels 4, 1, 3

Alternative Approach for Mild-Moderate DKA

• For uncomplicated mild-to-moderate DKA, subcutaneous rapid-acting insulin analogs combined with aggressive fluid management are equally effective, safer, and more cost-effective than IV insulin 4, 3
• This approach requires adequate fluid replacement, frequent point-of-care glucose monitoring, treatment of concurrent infections, and appropriate follow-up 4, 3
• Continuous IV insulin remains the standard of care for critically ill and mentally obtunded patients 4, 3

Electrolyte Management

Potassium Replacement Protocol

• Once adequate urine output is confirmed, add 20-30 mEq/L potassium to IV fluids (use 2/3 KCl and 1/3 KPO₄) if K+ is 3.3-5.5 mEq/L 4, 2, 3
• If K+ >5.5 mEq/L, withhold potassium initially but monitor closely, as levels will drop rapidly with insulin therapy 3
• Target serum potassium of 4-5 mEq/L throughout treatment 2, 3
• Monitor potassium levels closely—insulin administration drives potassium intracellularly and can cause life-threatening hypokalemia 1, 2, 3

Bicarbonate Administration

• Bicarbonate is NOT recommended for DKA patients with pH >6.9-7.0 4, 3
• Studies show no difference in resolution of acidosis or time to discharge with bicarbonate use 4, 3
• Bicarbonate may worsen ketosis, cause hypokalemia, and increase cerebral edema risk 4, 3

Monitoring During Treatment

• Draw blood every 2-4 hours to measure serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH 2, 3
• Follow venous pH (typically 0.03 units lower than arterial pH) and anion gap to monitor resolution of acidosis 3
• Direct measurement of β-hydroxybutyrate in blood is the preferred method for monitoring DKA 3
• Target glucose between 150-200 mg/dL until DKA resolution parameters are met 1, 3

Resolution Criteria and Transition

DKA Resolution Parameters

• 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 1, 3

Transition to Subcutaneous Insulin

• Administer basal insulin (glargine or detemir) 2-4 hours BEFORE stopping IV insulin infusion to prevent recurrence of ketoacidosis and rebound hyperglycemia 4, 1, 2, 3
• This overlap period is essential—stopping IV insulin without prior basal insulin administration is the most common error leading to DKA recurrence 2
• Once patient can eat, start multiple-dose schedule using combination of short/rapid-acting and intermediate/long-acting insulin 4, 2, 3
• Adding low-dose basal insulin analog during IV insulin infusion can help prevent rebound hyperglycemia without increased hypoglycemia risk 4, 3

Critical Pitfalls to Avoid

• Premature termination of insulin therapy before complete resolution of ketosis leads to DKA recurrence 3
• Interruption of insulin infusion when glucose levels fall causes persistent or worsening ketoacidosis—add dextrose instead 3
• Inadequate potassium monitoring and replacement is a leading cause of mortality in DKA 3
• Overly rapid correction of osmolality increases cerebral edema risk, particularly in children 3
• Failure to identify and treat underlying precipitating causes (infection, myocardial infarction, stroke, insulin omission) compromises treatment success 4, 3

Special Considerations

Thromboprophylaxis

• DKA creates a hypercoagulable state that increases thrombosis risk 1
• Enoxaparin can be started upon admission after initial fluid resuscitation as part of standard hospital thromboprophylaxis protocols 1
• Monitor renal function regularly, as insulin therapy and fluid resuscitation can improve kidney perfusion and change enoxaparin clearance 1

SGLT2 Inhibitors

• SGLT2 inhibitors must be discontinued 3-4 days before any planned surgery to prevent euglycemic DKA 4, 3
• Consider SGLT2 inhibitor use as a precipitating factor in patients presenting with DKA 3