What is the initial management of Diabetic Ketoacidosis (DKA)?

Initial Management of Diabetic Ketoacidosis (DKA)

The initial management of Diabetic Ketoacidosis (DKA) should begin with aggressive fluid resuscitation using isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour, followed by continuous intravenous insulin therapy and electrolyte replacement, particularly potassium. 1

Diagnosis and Initial Assessment

• DKA is diagnosed by the triad of hyperglycemia (blood glucose >250 mg/dL), metabolic acidosis (pH <7.3, bicarbonate <15 mEq/L), and moderate ketonuria or ketonemia 1
• Initial laboratory evaluation should include plasma glucose, blood urea nitrogen/creatinine, serum ketones, electrolytes with calculated anion gap, osmolality, urinalysis, arterial blood gases, and complete blood count 1
• Identify potential precipitating factors such as infection, cerebrovascular accident, alcohol abuse, pancreatitis, myocardial infarction, trauma, or medication non-adherence 1

Fluid Resuscitation

• Begin with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour to restore circulatory volume and renal perfusion 1
• Subsequent fluid choice depends on hydration status, serum electrolyte levels, and urine output 1
• Total body water deficit in DKA is typically significant and should be corrected within the first 24 hours 1
• Monitor fluid input/output, hemodynamic parameters, and clinical examination to assess progress with fluid replacement 1

Insulin Therapy

• After excluding hypokalemia (K+ <3.3 mEq/L), administer regular insulin as an intravenous bolus of 0.1 units/kg followed by continuous infusion at 0.1 units/kg/hour 1, 2
• If plasma glucose does not fall by 50-75 mg/dL in the first hour, double the insulin infusion rate hourly until a steady glucose decline is achieved 1
• For mild DKA only, subcutaneous or intramuscular insulin can be considered: give a "priming" dose of 0.4-0.6 units/kg (half IV bolus, half SC/IM), followed by 0.1 unit/hour SC/IM 1
• When blood glucose reaches 200-250 mg/dL, add dextrose to IV fluids while continuing insulin infusion at a reduced rate 1, 2

Electrolyte Management

• Potassium replacement is crucial as total body potassium is depleted despite potentially normal or elevated initial serum levels due to acidosis 1
• Once renal function is assured and serum potassium is known, add 20-40 mEq/L potassium to IV fluids when serum levels fall below 5.5 mEq/L 1
• The potassium in solution should be 1/3 KPO₄ and 2/3 KCl or K-acetate 1
• Bicarbonate therapy is generally not recommended unless pH is <6.9, as studies show no improvement in outcomes with its use 1
• Phosphate replacement may be considered in patients with cardiac dysfunction, anemia, respiratory depression, or serum phosphate <1.0 mg/dL 1

Monitoring

• Blood should be drawn every 2-4 hours for determination of serum electrolytes, glucose, BUN, creatinine, osmolality, and venous pH 1
• Venous pH (usually >7.3) and anion gap can be followed to monitor resolution of acidosis rather than repeated arterial blood gases 1
• Direct measurement of β-hydroxybutyrate in blood is preferred for monitoring ketoacidosis resolution, as the nitroprusside method only measures acetoacetic acid and acetone 1

Resolution Criteria and Transition of Care

• DKA resolution is defined as glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, and venous pH ≥7.3 1
• When transitioning from IV to subcutaneous insulin, continue IV insulin for 1-2 hours after starting subcutaneous insulin to prevent rebound hyperglycemia 1
• For patients who are NPO (nothing by mouth), continue IV insulin and supplement with subcutaneous regular insulin as needed 1
• When the patient can eat, start a multiple-dose schedule using a combination of short/rapid-acting and intermediate/long-acting insulin 1

Complications to Monitor

• Cerebral edema is a serious complication, especially in children and adolescents, and can be minimized by avoiding rapid correction of glucose and osmolality 3
• Hypokalemia can develop rapidly with insulin therapy and fluid resuscitation, potentially causing cardiac arrhythmias 2, 3
• Hypoglycemia may occur with overzealous insulin treatment 2

By following this structured approach to DKA management, focusing on fluid resuscitation, insulin therapy, and electrolyte replacement while monitoring for complications, mortality and morbidity can be significantly reduced.