With respect to plasma exchange therapy:
(a) What are the physical principles of plasma exchange therapy?
(b) What substances can plasma exchange effectively remove?
(c) List 5 acute conditions where therapeutic plasma exchange is indicated.
(d) List 4 common complications of this therapy, excluding catheter-related complications
With respect to plasma exchange therapy:
(a) What are the physical principles of plasma exchange therapy?
• Separation of plasma from blood cells by centrifugation or membrane filtration
• Reinfusion of cells plus autologous plasma or another replacement solution eg albumin
• Removes large molecular weight substances
(b) What substances can plasma exchange effectively remove?
• Pathogenic auto-antibodies
• Immune complexes
• Cryoglobulins
• Myeloma light chains
• Endotoxin
• Cholesterol-containing lipoproteins /triglycerides
(c) List 5 acute conditions where therapeutic plasma exchange is indicated.
Myasthenic Crisis
• Goodpasture’s Syndrome with pulmonary haemorrhage
• Hyperviscosity syndromes o Cryoglobulinaemia o Paraproteinaemia
o Waldenstrom’s Macroglobulinaemia
• Wegener’s Granulomatosis with pulmonary haemorrhage
• Guillain-Barre Syndrome/Acute Inflammatory Demyelinating Polyradiculopathy
• Antiphospholipid Antibody Syndrome
• HELLP syndrome
• Multiple sclerosis
• HIV-related neuropathy
• SLE
• Pemphigus
• Paraneoplastic syndromes
• Rapidly progressive glomerulonephritis
• Renal transplant rejection
• Coagulation inhibitors
• Auto-immune haemolytic anaemia
• DIC
• Overwhelming sepsis syndromes eg meningococcaemia
• Reye’s syndrome
• Paraquat poisoning
(d) List 4 common complications of this therapy, excluding catheter-related complications
• Hypotension due to excess fluid removal +/ inadequate volume replacement
• Citrate-induced hypocalcaemia
• Anaphylactic/transfusion reactions to fresh frozen plasma replacement solution
• Coagulation abnormalities due to removal of clotting factors not replaced when albumin replacement used.
• Removal of useful immunoglobulins and complement which can in theory lead to an immunodeficient state.
• Drug removal – especially drugs with high protein-binding and low volume of distribution. Potentials in the diseases in which therapeutic plasma exchange is used are cyclophosphamide and azathioprine.
• Hypothermia
• Pyrogenic reactions
• Anaemia
• Thrombocytopenia
• Hepatitis
• Vasovagal reactions
This college answer is an excellent concise overview of what is expected from the college fellows. Note the extensive lists. The candidates were not expected to generate this many indications or complications; the right number of anything from the college list would have earned marks. One can do little in the discussion of such a well-answered question, except provide references for more detailed reading.
Thus; most of the question can be answered after reading Jeffrey L. Winters' 2012 article fromHematology. Additionally, our very own college examiners have put a whole chapter on this technique into Oh's Manual (Chapter 97, pp. 993).
a) Principles of plasmapheresis
Characteristics of a disease process which make plasmapheresis an effective option:
b) Blood components removed by plasmapheresis
Undesirable blood components:
Desirable blood components which you'd rather keep:
c) Indications for urgent plasmapheresis
Urgent plasma exchange:
Less urgent plasma exchange:
One should note that in their list of indications, the college noted some Grade II, III and IV recommendations, such as:
d) Complications of plasmapheresis
McLeod, Bruce C. "Therapeutic apheresis: use of human serum albumin, fresh frozen plasma and cryosupernatant plasma in therapeutic plasma exchange."Best Practice & Research Clinical Haematology 19.1 (2006): 157-167.
Reimann, P. M., and P. D. Mason. "Plasmapheresis: technique and complications." Intensive care medicine 16.1 (1990): 3-10.
Winters, Jeffrey L. "Plasma exchange: concepts, mechanisms, and an overview of the American Society for Apheresis guidelines." ASH Education Program Book 2012.1 (2012): 7-12.
Oh's Manual: Chapter 97 (pp. 993) Therapeutic plasma exchange and intravenous immunoglobulin therapy by Ian Kerridge, David Collins and James P Isbister.
Szczepiorkowski, Zbigniew M., et al. "Guidelines on the use of therapeutic apheresis in clinical practice—Evidence‐based approach from the apheresis applications committee of the American Society for Apheresis." Journal of clinical apheresis 25.3 (2010): 83-177.
Russi, Gianpaolo, and Piero Marson. "Urgent plasma exchange: how, where and when." Blood Transfusion 9.4 (2011): 356.