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

Initial Management of Diabetic Ketoacidosis (DKA)

The initial treatment for a patient presenting with Diabetic Ketoacidosis (DKA) should begin with aggressive fluid resuscitation using isotonic saline (0.9% NaCl) at a rate of 15-20 mL/kg/hour during the first hour, followed by intravenous insulin therapy. 1, 2

Initial Assessment and Diagnosis

• Initial laboratory evaluation should include plasma glucose, blood urea nitrogen, creatinine, serum ketones, electrolytes with calculated anion gap, osmolality, urinalysis, arterial blood gases, complete blood count with differential, and electrocardiogram 2
• Direct measurement of β-hydroxybutyrate in blood is the preferred method for monitoring DKA 1, 2
• Bacterial cultures of urine, blood, and other sites should be obtained if infection is suspected 3

Fluid Therapy

• Begin with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 liters in the average adult) during the first hour to restore circulatory volume and tissue perfusion 3, 1
• Recent evidence suggests balanced electrolyte solutions may be superior to normal saline, with shorter time to DKA resolution 4
• Continue fluid replacement to correct estimated deficits within the first 24 hours, typically 1.5 times the 24-hour maintenance requirements (5 mL/kg/hour) 3
• Monitor fluid input/output, hemodynamic parameters, and clinical examination to assess progress with fluid replacement 2

Insulin Therapy

• After initial fluid resuscitation, administer an intravenous bolus of regular insulin at 0.15 U/kg body weight, followed by a continuous infusion at 0.1 U/kg/hour 2
• If plasma glucose does not fall by 50 mg/dL from the initial value in the first hour, double the insulin infusion rate until a steady glucose decline between 50-75 mg/hour is achieved 2
• Continue insulin therapy until resolution of ketoacidosis (pH >7.3, serum bicarbonate ≥18 mEq/L, and anion gap ≤12 mEq/L) 1, 2
• When blood glucose falls below 200-250 mg/dL, add dextrose to the hydrating solution while continuing insulin infusion to prevent hypoglycemia 1

Electrolyte Management

• Monitor potassium levels closely, as total body potassium deficits are common despite potentially normal or elevated initial serum levels due to acidosis 2
• Begin potassium replacement after serum levels fall below 5.5 mEq/L, assuming adequate urine output 3
• Generally, 20-30 mEq potassium (2/3 KCl and 1/3 KPO4) in each liter of infusion fluid is sufficient to maintain serum potassium between 4-5 mEq/L 3, 1
• If hypokalemia (K+ <3.3 mEq/L) is present at admission, begin potassium replacement before starting insulin therapy to avoid cardiac arrhythmias 3

Bicarbonate Therapy

• Bicarbonate therapy is generally not recommended for DKA patients with pH >7.0, as studies have failed to show beneficial effects on clinical outcomes 3, 2, 5
• For adult patients with pH <6.9, consider 100 mmol sodium bicarbonate added to 400 mL sterile water given at 200 mL/hour 3
• For patients with pH 6.9-7.0, consider 50 mmol sodium bicarbonate diluted in 200 mL sterile water infused at 200 mL/hour 3

Monitoring During Treatment

• Draw blood every 2-4 hours to determine serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH 1, 2
• Monitor for signs of cerebral edema, particularly in pediatric patients 3
• Target blood glucose levels of 100-180 mg/dL 2

Resolution Parameters

• DKA resolution requires glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH >7.3, and anion gap ≤12 mEq/L 1, 2
• Ketonemia typically takes longer to clear than hyperglycemia 1

Transition to Subcutaneous Insulin

• When transitioning to subcutaneous insulin, administer basal insulin 2-4 hours before stopping the intravenous insulin to prevent recurrence of ketoacidosis 1, 2
• Start a multiple-dose schedule using a combination of short/rapid-acting and intermediate/long-acting insulin when the patient is able to eat 1

Common Pitfalls to Avoid

• Premature termination of insulin therapy before complete resolution of ketosis can lead to recurrence of DKA 1, 2
• Inadequate fluid resuscitation can worsen DKA 1
• Interruption of insulin infusion when glucose levels fall without adding dextrose is a common cause of persistent or worsening ketoacidosis 1
• Clinical assessment often overestimates the degree of dehydration in DKA patients 6
• Failure to identify and treat precipitating factors such as infection, myocardial infarction, or stroke 1