exchange transfusion

Exchange transfusion involves the simultaneous removal of the patient's blood and replacement with donor blood or blood products, typically performed in aliquots to maintain hemodynamic stability. In neonates, it is indicated for severe unconjugated hyperbilirubinemia unresponsive to phototherapy (e.g., due to Rh or ABO hemolytic disease of the newborn) to prevent bilirubin-induced neurologic dysfunction (kernicterus), which can cause irreversible basal ganglia damage presenting with choreoathetosis, hearing loss, and upward gaze palsy. The procedure removes bilirubin, antibody-coated RBCs, and free antibodies, replacing them with antibody-negative donor blood. In sickle cell disease, exchange transfusion is used in acute chest syndrome, stroke, and priapism to rapidly decrease the percentage of HbS-containing RBCs (goal typically <30%) and reduce vaso-occlusive risk, while also preventing iron overload compared to simple transfusion since it removes excess iron-laden RBCs. Other indications include severe malaria (to reduce parasitemia), neonatal polycythemia, and certain cases of disseminated intravascular coagulation or toxin-mediated hemolysis. Complications include electrolyte imbalances (hypocalcemia, hyperkalemia), thrombocytopenia, infection, catheter-related complications, and transfusion reactions. Monitoring of bilirubin levels, electrolytes, and hematocrit is essential during and after the procedure.