What are the symptoms, signs, clinical picture, diagnosis, management, causes, and predisposing factors of Diabetic Ketoacidosis (DKA)?

Diabetic Ketoacidosis (DKA): Comprehensive Management Guide

DKA is a life-threatening medical emergency characterized by the triad of hyperglycemia, metabolic acidosis, and ketosis that requires immediate recognition and treatment to prevent mortality. 1

Clinical Presentation

Symptoms

• Polyuria, polydipsia, polyphagia
• Weight loss
• Nausea and vomiting (occurs in up to 25% of cases)
• Abdominal pain (specific to DKA, not HHS)
• Weakness and fatigue
• Progressive clouding of consciousness

Signs

• Dehydration (poor skin turgor)
• Kussmaul respirations (deep, rapid breathing)
• Tachycardia
• Hypotension
• Fruity breath odor (acetone)
• Mental status changes (ranging from alert to coma)
• Coffee-ground emesis (may indicate hemorrhagic gastritis)

Diagnostic Criteria for DKA 1

Parameter	Mild	Moderate	Severe
Plasma glucose	>250 mg/dL	>250 mg/dL	>250 mg/dL
Arterial pH	7.25-7.30	7.00-7.24	<7.00
Serum bicarbonate	15-18 mEq/L	10 to <15 mEq/L	<10 mEq/L
Urine/serum ketones	Positive	Positive	Positive
Effective serum osmolality	Variable	Variable	Variable
Anion gap	>10	>12	>12
Mental status	Alert	Alert/drowsy	Stupor/coma

Risk Factors and Precipitating Causes 1, 2

Risk Factors

• Type 1 diabetes/absolute insulin deficiency
• Younger age
• Prior history of DKA
• High A1C level
• Presence of behavioral health conditions (depression, eating disorders)
• Alcohol and substance use
• Social determinants of health

Common Precipitating Factors

• Infection (30-50% of cases, especially UTI and pneumonia)
• Insulin omission or inadequate insulin therapy
• New-onset diabetes (particularly type 1)
• Acute illness (surgery, trauma, myocardial ischemia, pancreatitis)
• Medications (glucocorticoids, thiazide diuretics, sympathomimetic agents)
• Psychological stress
• Pregnancy

Laboratory Evaluation 1

Initial workup should include:

• Plasma glucose
• Blood urea nitrogen/creatinine
• Serum ketones
• Electrolytes with calculated anion gap
• Serum osmolality
• Arterial blood gases
• Complete blood count with differential
• Urinalysis and urine ketones
• Electrocardiogram
• Bacterial cultures (blood, urine, throat) if infection suspected
• HbA1c (to determine if acute episode or chronic poor control)
• Chest X-ray if indicated

Differential Diagnosis 1

• Starvation ketosis
• Alcoholic ketoacidosis
• Lactic acidosis
• Salicylate, methanol, ethylene glycol, or paraldehyde ingestion
• Chronic renal failure
• Other causes of high anion gap metabolic acidosis

Management 1

1. Fluid Therapy

• Initial fluid therapy: 0.9% NaCl at 15-20 mL/kg/hr (1-1.5 L in first hour for adults)
• Subsequent fluid choice based on hydration status and electrolytes:
  • If corrected Na normal/high: 0.45% NaCl at 4-14 mL/kg/hr
  • If corrected Na low: 0.9% NaCl at similar rate
• Goal: Restore circulatory volume and tissue perfusion

2. Insulin Therapy

• Continuous intravenous insulin is the standard of care for critically ill and mentally obtunded patients 1
• Initial IV insulin: Regular insulin 0.1 units/kg/hr
• Continue until resolution of ketoacidosis (pH >7.3, bicarbonate >15 mEq/L)
• For uncomplicated DKA, subcutaneous rapid-acting insulin analogs may be used with aggressive fluid management
• Transition to subcutaneous insulin:
  • Administer basal insulin 2-4 hours before stopping IV insulin
  • Recent evidence suggests low-dose basal insulin analog with IV insulin may prevent rebound hyperglycemia

3. Electrolyte Replacement

• Potassium:
  • Once renal function is assured, add 20-30 mEq/L potassium (2/3 KCl and 1/3 KPO₄)
  • Goal: Maintain serum K between 4-5 mEq/L
• Bicarbonate:
  • Generally not recommended as studies show no difference in resolution of acidosis or time to discharge

4. Monitoring

• Frequent vital signs
• Hourly blood glucose measurements
• Electrolytes every 2-4 hours
• Continuous cardiac monitoring if indicated
• Fluid input/output
• Mental status

5. Treatment of Precipitating Cause

• Identify and treat underlying cause (especially infection)
• Administer appropriate antibiotics if infection suspected

Special Considerations

Transition from IV to Subcutaneous Insulin

• Administer basal insulin 2-4 hours before discontinuing IV insulin
• Continue IV insulin until subcutaneous insulin takes effect
• Ensure adequate oral intake before transition

Prevention of Recurrence 1

• Patients at risk for DKA should measure urine or blood ketones when:
  • Symptoms are present
  • During illness or missed insulin doses
  • Glucose levels exceed 200 mg/dL
• Mild DKA may be treated at home with:
  • Frequent blood glucose and ketone monitoring
  • Noncaloric hydration
  • Subcutaneous insulin administration
• Seek immediate medical attention if:
  • Unable to tolerate oral hydration
  • Blood glucose doesn't improve with insulin
  • Altered mental status develops
  • Signs of worsening illness appear

Complications of DKA

• Cerebral edema (more common in children)
• Acute respiratory distress syndrome
• Thromboembolism
• Acute kidney injury
• Hypokalemia or hyperkalemia
• Hypoglycemia during treatment
• Cardiac arrhythmias

Prognosis

With appropriate treatment, mortality from DKA is now <1% in developed countries. Poor prognostic factors include:

• Advanced age
• Coma at presentation
• Hypothermia
• Persistent hypotension
• Concurrent serious illness

Discharge Planning 1

• Structured discharge plan tailored to individual patient
• Clear communication with outpatient providers
• Education on:
  • Self-monitoring of blood glucose
  • When to check ketones
  • Insulin administration
  • Sick-day management
  • When to seek medical attention
• Follow-up appointment scheduled prior to discharge

DKA is a preventable complication with proper education, access to medical advice, and adequate follow-up care. Early recognition and prompt, aggressive treatment are essential to reduce morbidity and mortality.