Therapeutic Apheresis for Hematologic Emergencies

Abstract

Therapeutic apheresis (TA) refers to a range of procedures in which blood is removed from a patient; passed through a device to separate its components, most often discarding one (red cells, plasma, white cells, or platelets); and returned to the patient with or without extracorporeal modification or a replacement fluid. Multiple TA modalities can be used in the intensive care setting including therapeutic plasma exchange, red blood cell exchange, cellular depletions (leukocytapheresis, erythrocytapheresis), and extracorporeal photopheresis. This chapter will begin by discussing technical and patient-specific considerations to safely perform TA in critically ill patients, followed by a discussion of specific hematologic disorders in which TA may be indicated. Although many conditions treated with TA are done so without conclusive studies demonstrating its efficacy, evidence-based guidelines published by the American Society for Apheresis (ASFA) exist and are reviewed herein. When implemented in conjunction with an apheresis-trained physician, TA procedures can be lifesaving for patients with a variety of hematologic emergencies such as thrombotic thrombocytopenic purpura, hyperleukocytosis, and complications of sickle cell disease such as acute stroke, acute chest syndrome, and others.