Plasma filtration

Therapeutic plasma exchange (TPE) or plasmapheresis involves the separation of plasma from whole blood. In so doing, plasma-borne humoral disease mediators are removed from the body. This can attenuate the course and severity of the underlying disease. Diseases that can be treated with TPE are classified into the following categories: (1) endocrinological, (2) neurological, (3) renal/rheumatological, and (4) haematological. TPE is adjuvant in most of these settings. Disease-specific pharmacological treatment remains the cornerstone of treatment in many of these conditions. Plasma separation can be achieved with either (1) centrifugation (CF) or (2) membrane plasma filtration (PF). The latter is the focus of this review. It can be performed using either a continuous renal replacement therapy (CRRT) or haemodialysis (HD) machine. Standard plasma filtration has also been modified to incorporate sorbent technology which obviates the need for plasma volume replacement fluids. Larger clinical issues such as timing of initiation and intensity of therapy are examined.