What are the initial management steps for Diabetic Ketoacidosis (DKA)?

Initial Management of Diabetic Ketoacidosis (DKA)

Begin with aggressive isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 L in the average adult) during the first hour, followed by continuous intravenous regular insulin at 0.1 units/kg/hour once adequate hydration and potassium levels are confirmed. 1, 2

Immediate Diagnostic Confirmation

• Confirm DKA using laboratory criteria: blood glucose >250 mg/dL, arterial pH <7.3, serum bicarbonate <15 mEq/L, and presence of ketonemia or ketonuria 1, 2
• Obtain comprehensive laboratory evaluation: plasma glucose, blood urea nitrogen/creatinine, serum ketones, electrolytes with calculated anion gap, osmolality, urinalysis with urine ketones, arterial blood gases, complete blood count with differential, and electrocardiogram 1, 2
• Calculate corrected serum sodium by adding 1.6 mEq to the sodium value for each 100 mg/dL glucose above 100 mg/dL 2
• Obtain bacterial cultures (urine, blood, throat) if infection is suspected and administer appropriate antibiotics immediately 1, 2

Fluid Resuscitation Protocol

• Start with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour (approximately 1-1.5 L) during the first hour to restore circulatory volume and tissue perfusion 1, 2
• Total fluid replacement should aim to correct estimated deficits (typically 6L or 100 mL/kg) within 24 hours 1, 2
• When serum glucose reaches 250 mg/dL, switch fluid to 5% dextrose with 0.45-0.75% NaCl to prevent hypoglycemia while continuing insulin therapy 1

Critical pitfall: Premature addition of hypotonic fluids before adequate volume resuscitation can worsen cerebral perfusion. Always begin with isotonic saline regardless of calculated sodium levels. 1, 2

Insulin Therapy Initiation

• DO NOT start insulin if serum potassium is <3.3 mEq/L - aggressively replace potassium first to avoid life-threatening cardiac arrhythmias and respiratory muscle weakness 1
• Once K+ ≥3.3 mEq/L, administer intravenous bolus of regular insulin at 0.15 U/kg body weight, followed by continuous infusion at 0.1 U/kg/hour 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 complete resolution of ketoacidosis (pH >7.3, serum bicarbonate ≥18 mEq/L, and anion gap ≤12 mEq/L) regardless of glucose levels 1, 2

Critical pitfall: Interrupting insulin infusion when glucose falls below 250 mg/dL is a common cause of persistent or worsening ketoacidosis. Instead, add dextrose to IV fluids and continue insulin until acidosis resolves. 1

Potassium Management Algorithm

• If K+ <3.3 mEq/L: Delay insulin therapy and aggressively replace potassium until levels reach ≥3.3 mEq/L 1
• 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
• If K+ >5.5 mEq/L: Withhold potassium initially but monitor closely every 1-2 hours, as levels will drop rapidly with insulin therapy 1
• Target serum potassium of 4-5 mEq/L throughout treatment 1

Critical pitfall: Despite presenting with hyperkalemia, total body potassium depletion is universal in DKA. Insulin therapy will further lower serum potassium, making replacement critical even when initial levels appear normal or elevated. 1

Bicarbonate Administration

• Bicarbonate is NOT recommended for DKA patients with pH >6.9-7.0 1
• Studies show no difference in resolution of acidosis or time to discharge with bicarbonate use 1
• Bicarbonate may worsen ketosis, cause hypokalemia, and increase cerebral edema risk 1

Monitoring Protocol

• Draw blood every 2-4 hours to determine serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH 1
• 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
• Target glucose between 150-200 mg/dL until DKA resolution parameters are met 1

Resolution Criteria and Transition

• DKA is resolved when: glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH >7.3, and anion gap ≤12 mEq/L 1, 2
• Administer basal insulin (intermediate or long-acting) 2-4 hours BEFORE stopping IV insulin infusion to prevent recurrence of ketoacidosis and rebound hyperglycemia 1
• Once the patient can eat, start a multiple-dose schedule using a combination of short/rapid-acting and intermediate/long-acting insulin 1

Identification of Precipitating Factors

• Common triggers include: infection (most common), new-onset diabetes, insulin omission/inadequacy, myocardial infarction, cerebrovascular accident, pancreatitis, trauma, alcohol abuse, and drugs (corticosteroids, thiazides, sympathomimetic agents) 1, 2
• Discontinue SGLT2 inhibitors immediately as they can cause euglycemic DKA; these should be stopped 3-4 days before any planned surgery 1
• Treat underlying precipitating causes concurrently with DKA management 1, 2

Alternative Approach for Mild-Moderate Uncomplicated DKA

• For mild-to-moderate uncomplicated DKA in non-critically ill patients, subcutaneous rapid-acting insulin analogs combined with aggressive fluid management are equally effective, safer, and more cost-effective than IV insulin 1
• Continuous IV insulin remains the standard of care for critically ill and mentally obtunded DKA patients 1