What are the symptoms and management of diabetic ketoacidosis (DKA)?

Diabetic Ketoacidosis: Symptoms and Management

Clinical Presentation and Symptoms

The most common symptoms of DKA include polyuria, polydipsia, nausea, vomiting, abdominal pain, weight loss, severe fatigue, dyspnea, and preceding febrile illness. 1

• Patients may present with altered mental status ranging from alert (mild DKA) to drowsy (moderate DKA) to stupor/coma (severe DKA) 2
• Kussmaul respirations (deep, rapid breathing) occur as a compensatory mechanism for metabolic acidosis 1
• Dehydration signs including dry mucous membranes, poor skin turgor, and tachycardia are typically present 1

Diagnostic Criteria

DKA is diagnosed by blood glucose >250 mg/dL, venous pH <7.3, serum bicarbonate <15 mEq/L, and moderate ketonuria or ketonemia. 2

Severity Classification:

• Mild DKA: pH 7.25-7.30, bicarbonate 15-18 mEq/L 2
• Moderate DKA: pH 7.00-7.24, bicarbonate 10-15 mEq/L 2
• Severe DKA: pH <7.00, bicarbonate <10 mEq/L 2

Essential Laboratory Evaluation:

• Plasma glucose, electrolytes with calculated anion gap, serum ketones (β-hydroxybutyrate preferred), blood urea nitrogen/creatinine, osmolality, arterial or venous blood gases, complete blood count, urinalysis, and electrocardiogram 3, 4, 2
• Obtain bacterial cultures (urine, blood, throat) if infection suspected 4, 2
• Direct measurement of β-hydroxybutyrate is superior to nitroprusside method, which only detects acetoacetate and acetone 3, 2

Management Protocol

1. Fluid Resuscitation

Begin with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour during the first hour. 3, 4, 2

• Continue aggressive fluid management to restore circulatory volume and improve tissue perfusion 3
• Total fluid replacement should approximate 1.5 times the 24-hour maintenance requirements 4
• Add dextrose-containing fluids (5% dextrose with 0.45-0.75% NaCl) when blood glucose falls below 200-250 mg/dL to prevent hypoglycemia while continuing insulin therapy to clear ketosis 3, 2

2. Insulin Therapy

Start continuous intravenous regular insulin infusion at 0.1 units/kg/hour without an initial bolus (or with 0.1 units/kg bolus followed by 0.1 units/kg/hour infusion). 3, 4

• Never interrupt insulin infusion when glucose levels fall; instead, add dextrose to prevent hypoglycemia while continuing insulin to clear ketosis 3
• Continue insulin infusion until complete resolution of ketoacidosis: pH >7.3, serum bicarbonate ≥18 mEq/L, and anion gap ≤12 mEq/L 3, 2
• Ketonemia takes longer to clear than hyperglycemia, requiring continued insulin therapy regardless of glucose levels 3, 2

3. Electrolyte Management

Include 20-30 mEq/L potassium (2/3 KCl and 1/3 KPO₄) in the infusion once renal function is assured and serum potassium is <5.3 mEq/L. 3, 4

• Monitor potassium closely as insulin therapy and correction of acidosis drive potassium intracellularly, causing hypokalemia 3, 4
• Maintain serum potassium between 4-5 mmol/L throughout treatment 3
• Bicarbonate administration is generally not recommended for pH >6.9 due to risks of worsening ketosis, hypokalemia, and cerebral edema 2, 5
• Consider bicarbonate only if pH <6.9 or when pH <7.2 pre-intubation to prevent hemodynamic collapse 5

4. Monitoring During Treatment

Check blood glucose every 1-2 hours and draw blood every 2-4 hours to measure serum electrolytes, glucose, blood urea nitrogen, creatinine, osmolality, and venous pH. 3, 2

• Venous pH and anion gap adequately monitor acidosis resolution after initial diagnosis; repeated arterial blood gases are unnecessary 2
• Venous pH is typically 0.03 units lower than arterial pH 2

5. Transition to Subcutaneous Insulin

When DKA resolves (glucose stabilization, bicarbonate ≥18 mEq/L, pH >7.3, anion gap ≤12 mEq/L), administer basal insulin (glargine or detemir) 2-4 hours BEFORE stopping the intravenous insulin infusion. 3, 4, 2

• This overlap prevents recurrence of ketoacidosis and rebound hyperglycemia 3, 4
• Stopping IV insulin without prior basal insulin administration is the most common error leading to DKA recurrence 4
• Start a multiple-dose insulin schedule using combination of short/rapid-acting and intermediate/long-acting insulin once patient can eat 4

Critical Pitfalls to Avoid

• Premature termination of insulin therapy before complete resolution of ketosis (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L) 3, 2
• Interruption of insulin infusion when glucose levels fall without adding dextrose 3
• Inadequate monitoring and replacement of potassium, which can lead to life-threatening hypokalemia 3, 2
• Relying solely on nitroprusside method or urine ketones for monitoring, as these don't measure β-hydroxybutyrate, the predominant ketone body 3, 2
• Stopping IV insulin without administering basal insulin 2-4 hours prior 4
• Rapid overcorrection of hyperglycemia, which can precipitate cerebral edema, particularly in children 5

Special Considerations

Euglycemic DKA:

• Increasingly recognized in patients on SGLT2 inhibitors 3, 6, 1
• Requires earlier addition of dextrose-containing fluids to maintain adequate glucose while clearing ketosis 3
• Same insulin therapy principles apply despite normal or mildly elevated glucose 3

Severe DKA (pH <7.00):

• May require more intensive monitoring including central venous and intra-arterial pressure monitoring 2
• Higher risk of complications and mortality 2

Precipitating Causes:

• Identify and treat underlying precipitating factors (infection, medication non-compliance, new-onset diabetes, myocardial infarction) to prevent recurrence 4, 2, 1