Management of DKA in Adults

DKA Diagnostic Criteria (Confirm Before Starting)

• Hyperglycemia: glucose ≥200 mg/dL (11.1 mmol/L) for new-onset diabetes
• Venous pH < 7.3
• Serum bicarbonate (HCO3-) < 18 mEq/L
• At least moderate ketonuria (≥2+) OR ketonemia (BOHB ≥3 mmol/L)

Step 1 - Initial Assessment (STAT)

• Take full history and perform physical examination
• Obtain capillary glucose and serum or urine ketones
• Send STAT labs: ABG (or mixed venous blood gas), CBC with differential, urinalysis, serum glucose, BUN, electrolytes, chemistry profile, creatinine
• Obtain ECG; if needed: chest X-ray and blood/bacterial cultures

Step 2 - Fluid Resuscitation

• Start 1 L of 0.9% NaCl (or buffered crystalloid e.g. Lactated Ringer's) over 1 hour immediately
• Continue IV fluids based on hydration status and corrected serum Na+:
  • Corrected Na+ low or normal → 0.9% NaCl at 250-500 mL/hr
  • Corrected Na+ high → 0.45% NaCl at 250-500 mL/hr
• When glucose reaches 200 mg/dL → switch to 5% Dextrose + 0.45% NaCl (to allow continued insulin therapy without hypoglycemia)

Corrected Na+: Add 2 mEq to the measured sodium for every 100 mg/dL rise in glucose above 100 mg/dL

Step 3 - Potassium Replacement (Before Insulin!)

• Check serum K+ before starting insulin
• K+ < 3.5 mEq/L → Hold insulin; replace K+ at 20-40 mEq/hr IV until K+ ≥ 3.5 mEq/L, then start insulin
• K+ 3.5-5.0 mEq/L → Give KCl 20-30 mEq in each liter of IV fluid; start insulin
• K+ > 5.0 mEq/L → Start insulin; hold K+ replacement; recheck K+ every 2 hours

Step 4 - Insulin Therapy

• Do NOT start insulin if K+ < 3.5 mEq/L (risk of fatal hypokalemia)
• Fixed-rate IV insulin infusion: 0.1 units/kg/hr regular insulin (standard approach)
  • Alternative: Bolus 0.1 units/kg IV, then infusion at 0.1 units/kg/hr
• Variable-rate infusion is an acceptable alternative via nurse-driven protocol
• Target glucose fall: 50-75 mg/dL per hour
  • If glucose does not fall by 50-75 mg/dL in first hour → double insulin infusion rate
• When glucose reaches 200 mg/dL → reduce insulin to 0.02-0.05 units/kg/hr AND switch IV fluids to dextrose-containing solution

Step 5 - Bicarbonate Therapy (Selective Use)

• Generally not recommended in routine DKA
• Consider NaHCO3 only if:
  • pH < 6.9
  • Give 100 mEq NaHCO3 in 400 mL sterile water + 20 mEq KCl over 2 hours
  • Recheck pH every 2 hours; repeat until pH ≥ 7.0

Step 6 - Monitoring (Every 1-2 Hours)

• Capillary glucose every hour
• Serum electrolytes, BUN, creatinine, venous pH, phosphate every 2-4 hours
• Monitor urine output (target > 0.5 mL/kg/hr)
• Continuous cardiac monitoring (for K+ changes)
• Reassess fluid balance and clinical status frequently

Step 7 - Resolution Criteria (All Must Be Met)

• Blood glucose < 200 mg/dL
• Serum HCO3- ≥ 15 mEq/L
• Venous pH > 7.3
• BOHB < 0.6 mmol/L (or anion gap normal)

Step 8 - Transition to Subcutaneous Insulin

• When resolution criteria are met and patient can eat:
  • Give subcutaneous (SUBQ) long-acting insulin at least 1-2 hours BEFORE stopping IV insulin infusion (overlap period prevents rebound ketosis)
  • Resume prior insulin regimen if known; otherwise initiate new regimen
• If patient cannot eat → continue IV insulin infusion at low rate

Additional Points

• Identify and treat the precipitating cause (infection, missed insulin, new-onset T1DM, MI, etc.)
• Phosphate replacement only if severely low (< 1 mg/dL) with cardiac/respiratory compromise
• Cerebral edema (rare but serious): Watch for headache, altered mental status during treatment - manage with mannitol/hypertonic saline

Treatment of Diabetic Ketoacidosis in Adults

Complete Initial Evaluation*

• Check capillary glucose and serum/urine ketones to confirm hyperglycemia and ketonemia/ketonuria
• Start isotonic IV fluids (0.9% saline or buffered crystalloid): 1 L per hour
• Evaluate for precipitating cause(s)

IV Fluids

• Administer 0.9% saline or buffered crystalloid (approximately 1 L/hour; rate based on clinical assessment)

• Administer 0.9% saline or buffered crystalloid, rate based on clinical assessment
• If initial serum glucose is <250 mg/dL (13.9 mmol/L), add 5 to 10% dextrose to IV fluids upon treatment initiation

• Hemodynamic monitoring/pressors

• Correct volume deficit within 24 hours
• When volume deficit is corrected, adjust IV fluids based on serum Na+¶

• 0.45% saline (approximately 250 to 500 mL/hour)

• 0.9% saline (approximately 250 to 500 mL/hour)
• When serum glucose is <250 mg/dL (13.9 mmol/L), change to 5 to 10% dextrose with 0.45% saline at 150 to 250 mL/hour

• Check electrolytes, BUN, venous pH, phosphorus, creatinine, and glucose every 2 to 4 hours until stable
• Measure blood or serum BOHB every 2 hours
• After resolution of DKA and when patient is able to eat, initiate SUBQ multidose (basal-bolus) insulin regimen
• Continue IV insulin infusion for 1 to 2 hours after rapid-acting SUBQ insulin is begun to ensure adequate plasma insulin levels
• If short- or long-acting SUBQ insulin is initiated, continue IV insulin infusion for 2 to 4 hours
• In insulin-naive patients, start 0.5 to 0.6 units/kg per day (total daily dose), and adjust as needed

Potassium

• Delay insulin initiation and give 10 to 20 mEq KCl per hour until K+ >3.5 mEq/L

• Give 10 to 20 mEq of KCl in each liter of IV fluid to keep serum K+ between 4 to 5 mEq/L

• Do not give KCl but check serum K+ every 2 hours

Insulin

Moderate to Severe DKA (IV insulin)

• 0.1 units/kg/hour IV continuous insulin infusion^Δ
• If serum glucose does not fall by at least 50 to 70 mg/dL in the first hour, double the IV or SUBQ insulin rate/dose
• Decline in serum glucose should not exceed 90 to 120 mg/dL per hour

• Reduce regular insulin infusion to 0.05 units/kg/hour IV, or give rapid-acting insulin at 0.1 units/kg SUBQ every 2 hours
• Keep serum glucose between 150 to 200 mg/dL (8.3 to 11.1 mmol/L) until resolution of DKA
• Refer to UpToDate topic on the treatment of DKA in adults for resolution criteria

• Check electrolytes, BUN, venous pH, phosphorus, creatinine, and glucose every 2 to 4 hours until stable
• Measure blood or serum BOHB every 2 hours
• After resolution of DKA and when patient is able to eat, initiate SUBQ multidose (basal-bolus) insulin regimen
• Continue IV insulin infusion for 1 to 2 hours after rapid-acting SUBQ insulin is begun to ensure adequate plasma insulin levels
• If short- or long-acting SUBQ insulin is initiated, continue IV insulin infusion for 2 to 4 hours
• In insulin-naive patients, start 0.5 to 0.6 units/kg per day (total daily dose), and adjust as needed

Uncomplicated DKA (SUBQ Insulin)

• Rapid-acting insulin: 0.1 units/kg initial bolus, then 0.1 units/kg every hour or 0.2 units/kg every 2 hours

Assess Need for Bicarbonate

• Dilute NaHCO3 (100 mEq) in 400 mL sterile water
• If serum K+ is <5.0 mEq/L, add 20 mEq KCl
• Infuse over 2 hours
• Repeat NaHCO3 administration every 2 hours until pH >7.0

• No NaHCO3