Hemolytic reaction in the washed salvaged blood of a patient with paroxysmal nocturnal hemoglobinuria

BACKGROUND: In patients with paroxysmal nocturnal hemoglobinuria (PNH), the membrane-attack complex (MAC) formed on red blood cells (RBCs) causes hemolysis due to the patient’s own activated complement system by an infection, inflammation, or surgical stress. The efficacy of transfusion therapy for patients with PNH has been documented, but no studies have focused on the perioperative use of salvaged autologous blood in patients with PNH. CASE PRESENTATION: A 71-year-old man underwent total hip replacement surgery. An autologous blood salvage device was put in place due to the large bleeding volume and the existence of an irregular antibody. The potassium concentration in the transfer bag of salvaged RBCs after the wash process was high at 6.2 mmol/L, although the washing generally removes > 90% of the potassium from the blood. This may have been caused by continued hemolysis even after the wash process. Once activated, the complement in patients with PNH forms the MAC on the RBCs, and the hemolytic reaction may not be stopped even with RBC washing. CONCLUSIONS: Packed RBCs, instead of salvaged autologous RBCs, should be used for transfusions in patients with PNH. The use of salvaged autologous RBCs in patients with PNH should be limited to critical situations, such as massive bleeding. Physicians should note that the hemolytic reaction may be present inside the transfer bag even after the wash process.