What is the initial management of Diabetic Ketoacidosis (DKA) in the Intensive Care Unit (ICU)?

Initial ICU Management of Diabetic Ketoacidosis

Begin immediate aggressive fluid resuscitation with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour (approximately 1-1.5 liters in average adults), followed by continuous intravenous regular insulin infusion at 0.1 units/kg/hour once adequate hydration is established and potassium is >3.3 mEq/L. 1, 2, 3

Diagnostic Confirmation and Initial Assessment

Before initiating treatment, confirm DKA diagnosis requires all three criteria:

• Blood glucose >250 mg/dL 1, 3
• Arterial pH <7.3 1, 3
• Serum bicarbonate <15 mEq/L with positive ketones 1, 3

Obtain immediately:

• Plasma glucose, electrolytes with calculated anion gap, arterial blood gases, serum ketones (preferably β-hydroxybutyrate), BUN/creatinine, osmolality 2, 3
• Complete blood count, urinalysis, electrocardiogram 1, 3
• Bacterial cultures (blood, urine) if infection suspected 3, 4
• Direct β-hydroxybutyrate measurement is superior to nitroprusside method, which only detects acetoacetate and acetone 2, 4

Fluid Resuscitation Protocol

Hour 1: Aggressive Volume Expansion

• Isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour to restore intravascular volume and renal perfusion 1, 2, 3
• This translates to 1-1.5 liters in the first hour for average adults 1, 3
• Balanced electrolyte solutions may achieve faster DKA resolution than normal saline, though isotonic saline remains standard 4, 5

Subsequent Fluid Management

After initial resuscitation, adjust based on corrected sodium (add 1.6 mEq/L for every 100 mg/dL glucose >100 mg/dL):

• If corrected sodium is normal or elevated: 0.45% NaCl at 4-14 mL/kg/hour 1
• If corrected sodium is low: continue 0.9% NaCl at 4-14 mL/kg/hour 1
• When glucose reaches 250 mg/dL: switch to 5% dextrose with 0.45-0.75% NaCl to prevent hypoglycemia while continuing insulin 2, 3

Critical pitfall: Avoid osmolality changes exceeding 3 mOsm/kg/hour to prevent cerebral edema 4

Insulin Therapy

Timing and Dosing

• Do NOT start insulin if potassium <3.3 mEq/L - correct potassium first to prevent life-threatening arrhythmias 3, 4
• Start continuous IV regular insulin at 0.1 units/kg/hour without initial bolus (preferred for moderate-severe DKA) 2, 3, 4
• Some guidelines suggest 0.15 U/kg bolus followed by 0.1 U/kg/hour infusion 4

Insulin Adjustment

• If glucose does not fall by 50 mg/dL in first hour: verify adequate hydration, then double insulin infusion hourly until steady decline of 50-75 mg/h achieved 3, 4
• Target glucose decline: 50-75 mg/dL per hour 3
• Never stop insulin infusion when glucose falls - instead add dextrose to maintain glucose 150-200 mg/dL until ketoacidosis resolves 2, 3

Alternative for Mild Uncomplicated DKA

• Subcutaneous rapid-acting insulin analogs with aggressive fluid management may be equally effective, safer, and more cost-effective than IV insulin for mild-moderate uncomplicated DKA in non-critically ill patients 3, 4
• Continuous IV insulin remains mandatory for critically ill and mentally obtunded patients 3, 4

Potassium Management

Total body potassium is universally depleted in DKA despite potentially normal or elevated initial levels 3

Potassium Replacement Protocol

• If K+ <3.3 mEq/L: Hold insulin, aggressively replace potassium until ≥3.3 mEq/L to prevent cardiac arrhythmias and respiratory muscle weakness 3, 4
• If K+ 3.3-5.5 mEq/L: Add 20-30 mEq/L potassium to IV fluids (use 2/3 KCl and 1/3 KPO₄) once adequate urine output confirmed 1, 2, 3
• If K+ >5.5 mEq/L: Withhold potassium initially but monitor closely as levels will drop rapidly with insulin therapy 4
• Target serum potassium: 4-5 mEq/L throughout treatment 2, 3

Critical warning: Inadequate potassium monitoring and replacement is a leading cause of mortality in DKA 3

Bicarbonate Therapy

Bicarbonate is NOT recommended for pH >6.9-7.0 2, 3, 4

Evidence shows:

• No difference in resolution time or clinical outcomes 3, 4
• May worsen ketosis, cause hypokalemia, and increase cerebral edema risk 3, 4

Exception: Consider bicarbonate only if:

• pH <6.9: Give 100 mmol sodium bicarbonate in 400 mL sterile water at 200 mL/hour 4
• pH 6.9-7.0: Give 50 mmol sodium bicarbonate in 200 mL sterile water at 200 mL/hour 4
• Pre/post-intubation with pH <7.2 to prevent hemodynamic collapse from apnea 5

Monitoring Protocol

Frequency

• Blood glucose: every 1-2 hours 2
• Electrolytes, glucose, BUN, creatinine, osmolality, venous pH: every 2-4 hours 2, 3, 4
• Continuous cardiac monitoring to detect arrhythmias from electrolyte shifts 4

What to Monitor

• Venous pH (typically 0.03 units lower than arterial) and anion gap to track acidosis resolution 3, 4
• Fluid input/output and hemodynamic parameters 4
• β-hydroxybutyrate levels if available 2, 4

Resolution Criteria

DKA is resolved when ALL of the following are met:

• Glucose <200 mg/dL 3, 4
• Serum bicarbonate ≥18 mEq/L 2, 3, 4
• Venous pH >7.3 2, 3, 4
• Anion gap ≤12 mEq/L 2, 3, 4

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, 3, 4

British guidelines suggest adding subcutaneous insulin glargine alongside continuous IV insulin during treatment, which shows faster DKA resolution and shorter hospital stays 5

Once patient can eat:

• Start multiple-dose regimen combining short/rapid-acting with intermediate/long-acting insulin 3, 4
• For newly diagnosed patients: approximately 0.5-1.0 units/kg/day 4

Identification and Treatment of Precipitating Causes

Search for and treat concurrently:

• Infections (most common precipitant) - obtain cultures and start appropriate antibiotics 3, 4
• Myocardial infarction, stroke, pancreatitis, trauma 3, 4
• Insulin omission or inadequacy 1, 3
• SGLT2 inhibitors - discontinue immediately; should have been stopped 3-4 days before any planned surgery 3, 4

Critical Complications to Prevent

Cerebral Edema

• Rare but frequently fatal (0.7-1.0% in children) 4, 6
• Risk factors: severe acidosis, greater hypocapnia, higher BUN at presentation, bicarbonate treatment, rapid osmolality correction 6, 5
• Prevention: Avoid osmolality changes >3 mOsm/kg/hour, gradual glucose correction, judicious fluid management 4, 5

Hypokalemia

• Universal total body depletion despite initial levels 3
• Can cause cardiac arrhythmias, cardiac arrest, respiratory muscle weakness 3, 4

Hypoglycemia

• From continuing insulin without dextrose supplementation 2, 3
• Prevention: Add dextrose when glucose reaches 250 mg/dL, never stop insulin until ketoacidosis resolves 2, 3

Phosphate Replacement

Routine phosphate replacement is NOT recommended - studies show no beneficial effects on clinical outcomes 4

Consider only if: cardiac dysfunction, anemia, respiratory depression, or serum phosphate <1.0 mg/dL 4

Special Considerations for ICU Patients

• Continuous IV insulin at 0.1 units/kg/hour is standard of care for critically ill and mentally obtunded patients 3, 4
• Ensure adequate renal function before potassium replacement 1, 2
• Monitor for complications of severe DKA: altered mental status, stupor, coma 1
• Higher BUN at presentation increases cerebral edema risk 4

1, 2, 3, 4, 6, 5