Therapeutic plasma exchange: Procedure and medical applications

Therapeutic plasma exchange is a specialized medical procedure designed to remove macromolecular compounds from a patient's plasma, such as antibodies, immune complexes, cryoglobulins, lipoproteins, complement fractions, and von Willebrand factor polymers. During the process, blood is passed through a device that separates the plasma while returning cellular components—red cells, white cells, and platelets—to the body. The removed plasma is typically replaced with substitution fluids, such as 5% albumin or saline, and in specific cases, fresh frozen plasma.

The procedure requires vascular access via two peripheral venous catheters or a dual-lumen central venous catheter. Separation is achieved through centrifugation or membrane filtration, using citrate salts as anticoagulants to prevent clotting. A typical session involves exchanging 1 to 1.5 volumes of plasma (approximately 3 to 4 liters in adults) and lasts between 1.5 and 3 hours. Depending on the condition, patients usually undergo 5 to 7 sessions, performed daily or every other day.

Professor Thanos Dimopoulos, Director of the Therapeutic Clinic at Alexandras Hospital, notes that patients are continuously monitored for vital signs, fluid balance, and early signs of adverse reactions. While serious side effects are rare, potential complications include hypotension, circulatory shock due to sudden intravascular volume reduction, anaphylactic reactions to substitution fluids, and hypocalcemia.