Therapeutic Membrane Plasmapheresis
An Interview with Dr. Andre Kaplan, MD
We were lucky enough to be able to ask Dr. Andre Kaplan a few questions about plasmapheresis. Dr. Kaplan is currently Professor of Medicine at the University of Connecticut Health Center, Chief of Blood Purification at the John Dempsey Hospital, and Medical Director of the UConn Dialysis Unit. He has authored dozens of scientific papers on apheresis, and is one of the field's leading experts. We are incredibly grateful for his assistance, and we hope that this interview will help answer any questions that potential plasmapheresis patients might have.
How do you determine who is a candidate for plasmapheresis?
Plasmapheresis is a blood purification treatment designed for the removal of large molecular weight substances. In clinical practice, the common targets for removal are antibodies and other large proteins such as LDL cholesterol.
A LDL complex
In terms of an artificial organ system, when plasmapheresis is used to remove an antibody which is mediating an autoimmune disease, the treatment is acting like an artificial spleen. When the treatment is used for removal of LDL cholesterol, it is acting as an artificial liver. There are approximately 100 disease processes which have been considered as potential indications for plasmapheresis but because of their rarity only a few have undergone rigorous controlled trials to demonstrate the efficacy of the treatment. Commonly accepted indications for plasmapheresis are autoimmune diseases mediated by auto-antibodies such as myasthenia gravis, Goodpasture’s syndrome, thrombotic thrombocytopenic purpura and Guillain-Barré syndrome. Patients with very high cholesterol levels who have a genetic defect in the ability of their livers to clear LDL cholesterol can also be treated with plasmapheresis.
Can you define what a “successful” plasmapheresis treatment is?
If the target molecule (antibody, LDL cholesterol, etc) can be adequately removed and the clinical problem mediated by that molecule improves, then the treatment can be considered as successful.
No. However, the treatment often requires a large bore vascular access and placement of the access can be painful if insufficient anesthesia is used during its placement.
What are some common complications and how do you resolve them?
Citrate is commonly used as an anticoagulant and it works by complexing calcium. If calcium levels fall too low the patient will exhibit signs of hypocalcemia, including perioral and distal extremity parasthesias . . . this is the most common complication, but it is easily fixed with administration of calcium. Allergic type reactions to the protein containing replacement fluids are the most serious complications.
Citrate anticoagulant
Repetitive removal of the plasma’s clotting factors can cause a depletion coagulopathy . . . but this is also easily reversed with replacement of plasma containing the clotting factors. There are many other complications described, but they are not common (for more, see the Risks and Complications section).
What would be the worst-case scenario for the procedure?
Life-threatening anaphylaxis to the protein containing replacement fluid . . . with laryngeal edema. Requires emergency administration of epinephrine.
Epinephrine
How long does an average treatment last?
1 to 3 hours . . . depending on the blood flow capable through the patient’s vascular access . . . and the size of the patient.
How involved is the doctor in the actual treatment?
The doctor makes the indication, prescribes the amount of plasma to be exchanged, how often and when to repeat the treatment . . . chooses the replacement solution . . . and deals with the complications.
What are the major types of vascular access, and how do determine which is the most appropriate for a particular patient?
If the treatment is performed with a centrifuge, needles placed in the antecubital veins may be sufficient but in many cases a double lumen catheter is placed in a central vein.
What is the most difficult aspect of treating a patient with plasmapheresis?
Depends on the indication . . . often the most difficult decisions involve how many treatments to do and when to stop the treatments.
Are there specific dietary restrictions/requirements prior to coming in for plasmapheresis therapy?
None.
How will the patient feel after the treatment?
Fine . . . If the treatment is done for a particular indication, sometimes the patient feels improvement immediately. Such is the case for myasthenia gravis, where the paralysis associated with the disease may reverse rapidly during or immediately after the treatment.
How do you think plasmapheresis has evolved since you first went into practice?
More of the potential indications have undergone prospective, randomized, controlled trials which have either supported or negated the potential efficacy of plasmapheresis.
As a doctor, if you had one piece of information for patients undergoing plasmapheresis, what would it be?
Be certain that the treatment is being prescribed and performed by personnel who are familiar with its capabilities and its complications.
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Bio 1080 (Organ Replacement) - Spring 2008
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