Plasma exchange, also known as plasmapheresis, is a medical procedure designed to filter blood and remove harmful substances from the plasma. This intervention is employed to treat various conditions where the body’s plasma contains elements contributing to disease, such as abnormal antibodies or excess proteins. Like any significant medical treatment, plasma exchange carries potential risks that healthcare providers carefully consider against its anticipated benefits for each patient.
The Plasma Exchange Procedure
During a plasma exchange session, blood is drawn from a patient, typically through intravenous (IV) lines inserted into arm veins or, for prolonged treatments, a central catheter placed in a larger vein in the neck, chest, or groin. This blood then flows into a specialized machine called a blood cell separator. The machine uses either centrifugation, which separates components based on their different densities, or a membrane filter to separate the plasma from the other blood components, including red blood cells, white blood cells, and platelets.
Once separated, the patient’s plasma is collected and discarded. The remaining blood cells are then combined with a replacement fluid, such as an albumin solution or fresh frozen plasma (FFP), before being returned to the patient’s body through a separate IV line or lumen of the central catheter. An anticoagulant, often citrate, is added to the blood as it circulates through the machine to prevent clotting in the tubing. The entire process takes between one to three hours, depending on the volume of plasma being exchanged and the patient’s individual tolerance.
Potential Side Effects and Complications
While considered a safe procedure, plasma exchange can result in side effects and complications. Common, less severe reactions during the procedure include tingling, particularly around the lips or in the fingers and toes, which can be caused by the citrate anticoagulant binding to calcium in the blood. Patients may also feel dizzy, light-headed, or nauseated, largely due to a temporary drop in blood pressure. These symptoms are transient and can be managed by the nursing staff.
Less common but more serious complications may arise. Allergic reactions to the replacement fluids, such as albumin or fresh frozen plasma, may occur, presenting as hives, chills, fever, or, rarely, anaphylactic responses. There is also a risk of infection at the IV or central catheter insertion site, as this provides a direct pathway into the bloodstream. Bleeding or clotting issues can develop; the procedure can temporarily reduce the levels of clotting factors in the blood, or, in rare instances, a blood clot might form within the apheresis machine itself.
How Medical Teams Mitigate Risks
Medical teams implement safety protocols and measures to minimize the risks associated with plasma exchange. Continuous monitoring of vital signs, including blood pressure, heart rate, and oxygen saturation, is performed throughout the procedure to identify and address any adverse reactions. Nursing staff are present to observe for symptoms such as dizziness, tingling, or nausea, and can adjust the procedure’s rate or temporarily pause it if discomfort arises.
Blood tests are conducted before the procedure to assess a patient’s baseline health and electrolyte levels. The type and volume of replacement fluid are calculated and selected to maintain blood volume stability. To counteract the calcium-binding effect of citrate, calcium supplements may be administered during the exchange to prevent hypocalcemia. All tubing and needles used are sterile and single-use, reducing the risk of infection.
Patient-Specific Risk Considerations
Patient-specific factors influence the risk of plasma exchange and susceptibility to complications. A patient’s underlying medical condition impacts the overall risk profile. Patients with pre-existing cardiovascular issues or kidney impairment may experience different responses to fluid shifts or electrolyte changes during the procedure.
The patient’s overall health status, including age and other medical conditions, also plays a role in determining potential risks. Individuals with active infections or those on certain medications may require adjustments or temporary cessation of their drugs before the exchange. The type of vascular access used, such as peripheral IV lines or central venous catheters, also carries considerations, with central lines having a slightly higher, though small, risk of complications like infection or bleeding. Before recommending plasma exchange, medical teams conduct a risk assessment, weighing these factors against the anticipated therapeutic benefits.