Dialysis and Renal Replacement Therapy
Core concepts
Renal replacement therapy includes hemodialysis, peritoneal dialysis, and continuous renal replacement therapy. Urgent indications are summarized by AEIOU: acidosis, electrolyte disturbance (especially hyperkalemia), intoxication, fluid overload, and uremic complications such as encephalopathy or pericarditis. Hemodialysis provides rapid clearance but requires vascular access and can cause hypotension or disequilibrium syndrome. Peritoneal dialysis is often preferred in infants and hemodynamically unstable children because it is gentle and does not require vascular access. Continuous renal replacement therapy is useful in critically ill patients with hemodynamic instability. Monitor adequacy, residual renal function, access complications, and medication dosing.
Traps
Dialysis is not indicated for every case of AKI; treat the patient, not the creatinine. Do not perform rapid dialysis in a child with severe uremia without considering disequilibrium syndrome. Peritonitis is a major PD complication and presents with abdominal pain, cloudy effluent, and fever; send effluent for cell count and culture. In hemodialysis, be alert for air embolism, hemolysis, and access infection. Drug dosing changes with dialysis.
Worked example / rule of thumb
A child with AKI, anuria, pulmonary edema, and refractory hyperkalemia needs urgent dialysis; if hemodynamically unstable, choose CRRT. Rule: AEIOU reminds you of urgent indications; PD is gentle for infants, while HD is fast for poisoning or severe hyperkalemia.