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

Initial Management of Diabetic Ketoacidosis (DKA)

Begin with aggressive 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 and replacing potassium to maintain levels between 4-5 mEq/L. 1, 2

Immediate Assessment and Diagnosis

Confirm DKA Diagnosis

• Verify all three diagnostic criteria are met: blood glucose >250 mg/dL, arterial pH <7.3, serum bicarbonate <15 mEq/L, and presence of ketonemia or ketonuria 2, 3
• Obtain comprehensive laboratory evaluation including plasma glucose, blood urea nitrogen/creatinine, serum ketones (preferably β-hydroxybutyrate), electrolytes with calculated anion gap, osmolality, urinalysis, arterial blood gases, complete blood count, and electrocardiogram 1, 2
• Direct measurement of β-hydroxybutyrate in blood is preferred over nitroprusside method, which only detects acetoacetic acid and acetone, not the predominant ketone body 1, 2

Identify Precipitating Factors

• Obtain bacterial cultures (urine, blood, throat) if infection is suspected and administer appropriate antibiotics 2, 3
• Consider other triggers: myocardial infarction, stroke, pancreatitis, trauma, insulin omission/inadequacy, or SGLT2 inhibitor use 2, 4

Fluid Resuscitation Protocol

Initial Fluid Therapy

• 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 to restore circulatory volume and tissue perfusion 1, 2, 3
• Total fluid replacement should aim to correct estimated deficits (typically 6L or 100 mL/kg) within 24 hours 2, 3

Subsequent Fluid Management

• When serum glucose reaches 200-250 mg/dL, switch to 5% dextrose with 0.45-0.75% NaCl while continuing insulin therapy 1, 2
• Critical pitfall to avoid: Never interrupt insulin infusion when glucose levels fall; instead, add dextrose to prevent hypoglycemia while continuing insulin to clear ketosis 1, 2

Insulin Therapy

Initiation and Dosing

• Start continuous intravenous regular insulin infusion at 0.1 units/kg/hour without an initial bolus (preferred method for moderate to severe DKA) 1, 2
• For critically ill and mentally obtunded patients, continuous IV insulin at 0.1 units/kg/hour is the standard of care 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 2

Alternative for Mild-Moderate Uncomplicated DKA

• Subcutaneous rapid-acting insulin analogs combined with aggressive fluid management are equally effective, safer, and more cost-effective than IV insulin for uncomplicated mild-moderate DKA 2
• However, continuous IV insulin remains standard for critically ill and mentally obtunded patients 2

Duration of Insulin Therapy

• Continue insulin infusion until complete resolution of ketoacidosis (pH >7.3, serum bicarbonate ≥18 mEq/L, and anion gap ≤12 mEq/L) regardless of glucose levels 1, 2
• Premature termination of insulin therapy before complete resolution of ketosis is a common pitfall that leads to recurrence of DKA 1, 2

Electrolyte Management

Potassium Replacement - Critical Priority

• If K+ <3.3 mEq/L, delay insulin therapy and aggressively replace potassium until levels reach ≥3.3 mEq/L to prevent life-threatening arrhythmias and respiratory muscle weakness 2
• Despite potentially normal or elevated initial serum levels due to acidosis, total body potassium depletion is universal in DKA, and insulin therapy will further lower serum potassium 2, 3
• If K+ 3.3-5.5 mEq/L, add 20-30 mEq potassium per liter of IV fluid (use 2/3 KCl and 1/3 KPO₄) once adequate urine output is confirmed 1, 2, 3
• If K+ >5.5 mEq/L, withhold potassium initially but monitor closely, as levels will drop rapidly with insulin therapy 2
• Maintain serum potassium between 4-5 mEq/L throughout treatment 1, 2

Bicarbonate - Generally NOT Recommended

• Bicarbonate administration is NOT recommended for DKA patients with pH >6.9-7.0, as studies show no difference in resolution of acidosis or time to discharge 2
• Bicarbonate may worsen ketosis, cause hypokalemia, and increase cerebral edema risk 2, 5
• Consider 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 5

Monitoring During Treatment

Laboratory Monitoring Frequency

• Check blood glucose every 1-2 hours 1
• 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 2

Cerebral Edema Surveillance

• Monitor for signs of cerebral edema, particularly in children and adolescents, as this is the most dire complication of DKA 6, 7
• Risk factors include severity of acidosis, greater hypocapnia, higher blood urea nitrogen at presentation, and treatment with bicarbonate 6
• Avoid overly rapid correction of osmolality, which increases cerebral edema risk 2, 5

Resolution Criteria and Transition

DKA Resolution Parameters

• DKA is resolved when all criteria are met: glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH >7.3, and anion gap ≤12 mEq/L 2, 3
• Target glucose between 150-200 mg/dL until DKA resolution parameters are met 2

Transition to Subcutaneous Insulin

• Administer basal insulin (intermediate or long-acting) 2-4 hours BEFORE stopping IV insulin infusion to prevent recurrence of ketoacidosis and rebound hyperglycemia 2
• Administration of low-dose basal insulin analog in addition to IV insulin infusion may prevent rebound hyperglycemia without increasing hypoglycemia risk 1, 2
• Once the patient can eat, start a multiple-dose schedule using a combination of short/rapid-acting and intermediate/long-acting insulin 2

Special Considerations

SGLT2 Inhibitors

• Discontinue SGLT2 inhibitors 3-4 days before any planned surgery to prevent euglycemic DKA 2
• Be aware of euglycemic DKA in patients prescribed SGLT2 inhibitors, where blood glucose may be normal or only mildly elevated despite meeting other DKA criteria 1, 4

Euglycemic DKA Management

• Add dextrose-containing fluids (5% dextrose with 0.45-0.75% NaCl) earlier in treatment to maintain adequate glucose levels while continuing insulin therapy to clear ketosis 1
• Never interrupt insulin infusion when glucose levels fall in euglycemic DKA; inadequate carbohydrate administration alongside insulin can perpetuate ketosis 1