What are the complications of diabetic ketoacidosis (DKA) and how are they managed?

Complications of Diabetic Ketoacidosis

Most Critical Complication: Cerebral Edema

Cerebral edema is the most feared complication of DKA, particularly in children, and requires immediate recognition and treatment to prevent mortality. 1 Prevention measures include gradual replacement of sodium and water deficits in hyperosmolar patients (maximal reduction in osmolality 3 mOsm/kg H2O/hour) and adding dextrose to hydrating solutions once blood glucose reaches 250 mg/dL. 1

Treatment-Related Complications

Hypoglycemia

• The most common complication results from overzealous insulin treatment. 1
• Occurs when insulin administration continues without adequate glucose monitoring or dextrose supplementation. 1
• Prevention requires adding dextrose to IV fluids once glucose reaches 250 mg/dL and maintaining glucose at 250-300 mg/dL in HHS until hyperosmolarity and mental status improve. 1

Hypokalemia

• Results from insulin administration and bicarbonate treatment of acidosis, representing a critical electrolyte emergency. 1
• Total body potassium is depleted in DKA despite potentially normal or elevated initial serum levels. 2, 3
• Requires proactive potassium supplementation targeting serum levels of 4-5 mEq/L throughout treatment. 2
• Can precipitate life-threatening cardiac arrhythmias including atrial flutter. 3
• Monitoring every 2-4 hours during treatment is essential to prevent arrhythmias. 3

Hyperglycemia Rebound

• Occurs when IV insulin is discontinued without prior subcutaneous basal insulin administration. 1
• Basal insulin must be given 2-4 hours BEFORE stopping IV insulin to prevent recurrence of ketoacidosis. 1, 2

Hyperchloremic Non-Anion Gap Metabolic Acidosis

• Develops from excessive saline use for fluid replacement. 1
• Chloride from IV fluids replaces ketoanions lost during osmotic diuresis. 1
• This is transient and not clinically significant except in acute renal failure or extreme oliguria. 1

Pulmonary Complications

Hypoxemia and Noncardiogenic Pulmonary Edema

• Hypoxemia results from reduced colloid osmotic pressure causing increased lung water content and decreased lung compliance. 1
• Patients with widened alveolo-arterial oxygen gradient on initial blood gas or pulmonary rales on examination are at higher risk. 1, 2
• Aggressive fluid resuscitation can lead to significant fluid retention and edema, as patients typically receive 1.5 times their 24-hour maintenance fluid requirements. 2

Cardiovascular Complications

Cardiac Arrhythmias

• Electrolyte imbalances, particularly potassium abnormalities, trigger cardiac arrhythmias including atrial flutter. 3
• Volume depletion causes hemodynamic stress increasing arrhythmia risk. 3
• Continuous cardiac monitoring is crucial in severe DKA (pH < 7.0, bicarbonate < 10 mEq/L). 3
• Severity of electrolyte disturbances and degree of dehydration directly correlate with arrhythmia risk. 3

High-Risk Populations

Pregnancy

• Up to 2% of pregnancies with pregestational diabetes are complicated by DKA, with significant risk of feto-maternal harm. 1
• Pregnant individuals may present with euglycemic DKA (glucose <200 mg/dL). 1
• Diagnosis may be hindered by mixed acid-base disturbances, particularly with hyperemesis. 1
• Immediate medical attention is required if DKA is suspected. 1

SGLT2 Inhibitor Users

• SGLT2 inhibitors must be discontinued 3-4 days before surgery to prevent perioperative DKA. 1
• Risk factors include very-low-carbohydrate diets, prolonged fasting, dehydration, excessive alcohol intake, and presence of autoimmunity. 1
• DKA occurs at 0.6-4.9 events per 1,000 patient-years in type 2 diabetes patients on SGLT2 inhibitors. 1

Mortality and Morbidity

• DKA mortality is 5% in experienced centers, while HHS mortality remains 15%. 1
• Prognosis worsens at extremes of age and with coma and hypotension. 1
• Each DKA episode requires substantial healthcare resources, averaging $13,000 per hospitalization. 4
• Recurrent DKA is associated with significantly greater diabetes morbidity and mortality. 4

Prevention of Complications

Critical Monitoring Parameters

• Blood glucose every 2-4 hours while NPO. 1
• Electrolytes, especially potassium, every 2-4 hours during treatment. 3
• Daily weights to track fluid status objectively. 2
• Renal function to ensure adequate kidney function and avoid prerenal azotemia. 2

Fluid Management Pitfalls

• Confirm DKA resolution (pH >7.3, bicarbonate ≥18 mEq/L, anion gap ≤12 mEq/L) before transitioning to subcutaneous insulin. 2
• Rule out cardiac dysfunction as noncardiogenic pulmonary edema can complicate treatment. 2
• Check for renal impairment as acute kidney injury can impair fluid excretion. 2