How to manage Diabetic Ketoacidosis (DKA)?

Management of Diabetic Ketoacidosis (DKA)

The management of DKA requires immediate fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour, followed by continuous intravenous regular insulin infusion at 0.1 units/kg/hour without an initial bolus, while closely monitoring electrolytes, particularly potassium. 1, 2

Initial Assessment and Diagnosis

• Diagnostic criteria for DKA include: blood glucose >250 mg/dL, arterial pH <7.3, serum bicarbonate <15 mEq/L, and presence of ketonemia or ketonuria 1
• Laboratory evaluation should include plasma glucose, blood urea nitrogen/creatinine, serum ketones, electrolytes (with calculated anion gap), osmolality, urinalysis, urine ketones, arterial blood gases, complete blood count with differential, and electrocardiogram 1, 2
• Obtain bacterial cultures (urine, blood, throat) if infection is suspected and administer appropriate antibiotics 2
• Identify potential precipitating factors: infection, cerebrovascular accident, alcohol abuse, pancreatitis, myocardial infarction, trauma, drugs, or insulin discontinuation/inadequacy 1

Treatment Protocol

Fluid Therapy

• Begin with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 L in the average adult) during the first hour 1, 2
• Subsequent fluid choice depends on hydration status, serum electrolyte levels, and urine output 1
• When serum glucose reaches 250 mg/dL, change fluid to 5% dextrose with 0.45-0.75% NaCl to prevent hypoglycemia while continuing insulin therapy 1
• Total fluid replacement should aim to correct estimated deficits within 24 hours 2

Insulin Therapy

• Start with continuous intravenous regular insulin infusion at 0.1 units/kg/hour (preferred method for moderate to severe DKA) without an initial bolus 1, 2
• If plasma glucose does not fall by 50 mg/dL from initial value in the first hour, check hydration status; if acceptable, double the insulin infusion rate every hour until a steady glucose decline of 50-75 mg/h is achieved 1
• Continue insulin infusion until resolution of ketoacidosis (pH >7.3, serum bicarbonate ≥18 mEq/L, and anion gap ≤12 mEq/L) regardless of glucose levels 1, 2
• When serum glucose reaches 250 mg/dL, decrease insulin infusion to 0.05-0.1 units/kg/hour and add dextrose to IV fluids 2

Electrolyte Management

• Include 20-30 mEq/L potassium (2/3 KCl and 1/3 KPO₄) in the infusion once renal function is assured and serum potassium is <5.3 mEq/L 1, 2
• Monitor potassium levels closely, as insulin administration can cause hypokalemia; maintain serum K⁺ between 4-5 mmol/L 1, 2
• In patients with relatively low plasma potassium levels, temporarily delay insulin administration and first administer potassium chloride intravenously to bring plasma potassium close to 4 mmol/L 3
• Bicarbonate administration is generally not recommended for DKA patients with pH >6.9 2

Monitoring During Treatment

• Check blood glucose every 1-2 hours 2
• Draw blood every 2-4 hours to determine serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH 1, 2
• Follow venous pH (typically 0.03 units lower than arterial pH) and anion gap to monitor resolution of acidosis 1
• Direct measurement of β-hydroxybutyrate in blood is the preferred method for monitoring DKA, as the nitroprusside method only measures acetoacetic acid and acetone 1

Resolution Parameters and Transition to Subcutaneous Insulin

• DKA resolution requires: glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH >7.3, and anion gap ≤12 mEq/L 1, 2
• When DKA resolves and the patient can eat, start a multiple-dose insulin schedule using a combination of short/rapid-acting and intermediate/long-acting insulin 1, 2
• Administer basal insulin 2-4 hours before stopping the IV insulin infusion to prevent recurrence of ketoacidosis 2

Common Pitfalls to Avoid

• Premature termination of insulin therapy before complete resolution of ketosis can lead to recurrence of DKA 1, 2
• Interruption of insulin infusion when glucose levels fall without adding dextrose is a common cause of persistent or worsening ketoacidosis 1, 2
• Failure to add dextrose when glucose falls below 250 mg/dL while continuing insulin therapy 1
• Inadequate monitoring and replacement of electrolytes, particularly potassium 1, 2
• Overzealous fluid resuscitation and rapid correction of hyperglycemia may contribute to cerebral edema, particularly in children 4
• Relying on nitroprusside method to measure ketones is misleading as it only measures acetoacetic acid and acetone, not β-hydroxybutyrate 2