Gray, Kristin

ABSTRACT Collection of hematopoietic progenitor cells and mononuclear cells by leukocytapheresis is a critical step of procuring cellular starting materials for future therapeutic use. Leukocytapheresis requires use of anticoagulant to prevent blood clotting in the extracorporeal circuit during collection. A commonly used anticoagulant is Acid Citrate Dextrose Solution A (ACD‐A). ACD‐A primarily prevents blood clotting by reversibly chelating free ionized calcium, which is essential for the clotting cascade. Electrolytes frequently affected by ACD‐A include calcium, magnesium, potassium, phosphate, and bicarbonate. Risks for development of electrolyte derangements include procedure‐related parameters as well as patient comorbidities. Symptoms range from mild paresthesias to life‐threatening cardiac arrhythmias. Recognition of related signs and symptoms is important for prompt intervention with procedure modification and electrolyte replacement to optimize patient safety. This paper will provide an enhanced understanding of the underlying pathophysiology and assist in timely identification and management of electrolyte abnormalities associated with cellular therapy collections.

Abstract This manuscript describes a novel approach for treating patients with long‐term sequelae from hemoglobin Evans (Hb Evans). After instituting conservative therapies for approximately 2 years, our patient's symptoms continually worsened. Therefore, we performed red blood cell exchange (RBCx) to reduce his Hb Evans percentage and his co‐existing elevation of methemoglobin. Our assumptions of clinical benefit were based on our collective experience performing RBCx for patients with sickle cell disease. After the first exchange, pre‐ and post‐laboratory results supported our approach and the patient experienced marked improvement in his clinical signs and symptoms. This report provides preliminary proof of principle for the use of RBCx to treat Hb Evans and other non‐Hb S hemoglobinopathies.