Plasmapheresis is a therapeutic intervention that involves extracorporeal removal, return, or exchange of blood plasma or components.[1][2] The underlying mechanism of this procedure is accomplished by either centrifugation or filtration using semipermeable membranes. While centrifugation is based on the principle of separation using different specific gravities of various blood components, membrane plasma separation filters blood components based on their particle size.[3][4]
The preferred method of plasmapheresis in most centers worldwide is by automated centrifuge-based technology.[5] However, in certain hospitals and patients on hemodialysis, plasmapheresis is done using membrane plasma separation.[3] In plasmapheresis using centrifugation, filtered plasma is discarded, and RBCs and replacement fluid (donor plasma or colloids) are returned. Membrane plasma separation allows selective removal of undesired macromolecules; hence, filtered, processed plasma is returned to the patient, eliminating the need for replacement fluids.
In this review, we will discuss the indications, contraindications, equipment, preparation, procedure, and complications of plasmapheresis.
Therapeutic plasmapheresis is used for numerous diseases. The conditions involve the presence of a toxic substance in plasma (e.g., immunoglobulin), which can be filtered. The disorders where therapeutic plasmapheresis can be done are grouped into four categories by the Apheresis Applications Committee of the American Society for Apheresis (ASFA). Category 1 includes disorders where plasmapheresis can be done as a first-line treatment, category 2 includes disorders where plasmapheresis can be done as a second-line treatment in addition to the existing standard of care, category 3 includes disorders in which the evidence of the benefit of plasmapheresis is minimal, and therapy must be individualized, and category 4 includes disorders in which the evidence suggests that plasmapheresis is either ineffective or harmful, however, may be considered after approval from the institute ethics committee.[2]
The alphabetical list of various indications for plasmapheresis, along with their ASFA category, is as follows.
Category 1
Category 2
Category 3
Category 4
The contraindications for therapeutic plasmapheresis are as follows:[1]
Venous access for this procedure is either by a central venous catheter or large bore peripheral lines. There are multiple manufacturers of the centrifuge-based plasmapheresis machines.
Another technique of performing plasmapheresis is by using semipermeable membrane filters with a standard hemodialysis machine. However, for this technique, central venous access is mandatory due to the need for higher blood flow rates of 100 mL/min to 150 mL/min. There are two membrane-based technologies that are currently available; hollow fiber and parallel plate. Hollow fiber dialyzers are cylindrical shell-like structures, consisting of multiple polysulfone capillary fibers.
Parallel plate dialyzers consist of layered membranes, with ridges and grooves which facilitate filtration. Both these dialyzers allow plasma filtration based on particle size and pressure gradients. Hollow fiber dialyzers are more gentle as opposed to parallel plate dialyzers and are preferred for pediatric patients, whereas hollow fiber dialyzers use less blood volume, and hence require a reduced dose of citrate or heparin for anticoagulation.
The major advantage of membrane-based plasmapheresis over centrifuge-based technology is that the removed processed-plasma by ultrafiltration can be returned to the patient eliminating the need for replacement fluids or colloids.[1]
Plasmapheresis was traditionally performed in blood banks by centrifuge-based techniques. However, therapeutic plasmapheresis procedures are routinely performed by critical care specialists in the intensive care unit, nephrologists, and dialysis-technicians after specialized skill-based training.
No specific patient preparation is needed for this procedure. However, while inserting a central line, a local anesthetic may be needed. For this purpose, 2% lidocaine injection is used routinely. In pediatric patients, sedation with opioids and benzodiazepines may be considered for pain and anxiety control.
The patient is positioned supine for plasmapheresis; however, the position, especially of the neck, may be altered according to the location of central venous access to maintain adequate blood flow throughout the procedure.
A close watch on patient vitals is recommended throughout the procedure to assess for volume depletion, hypocalcemia, and complications of fresh frozen plasma transfusion.
The steps for performing plasmapheresis using centrifuge-based equipment are as follows:[6]
The common complications that can occur during or post-plasma exchange procedure are as follows:
Plasmapheresis offers an effective therapy for many acute and chronic diseases. It can also be used as an adjunct to prepare for procedures, surgery, and even improve postoperative recovery or shorten ventilation periods. Generally, risks and side effects are mild, most common being transient hypotension and related symptoms.[9][10]
The American Society for Apheresis has done extensive research on plasmapheresis as a therapeutic strategy, and continue to update a comprehensive apheresis guideline using an evidence-based approach to aid physicians caring for these patients.[10] Using this evidence-based resource is the best way to standardize care and provide innovation.[9][10]
Plasmapheresis is an intensive care procedure that needs appropriate decisions, specialized skill-based training, close monitoring, and follow-up for best clinical outcomes. It is recommended that a customized dedicated chart must be designed at all centers performing plasmapheresis procedures. This should include a brief history, with established/presumptive diagnosis.
The basis for the procedure, along with patient-specific concerns, must be listed. This chart should also indicate the total number of plasmapheresis sessions planned. The healthcare professionals must clearly discuss the clinical and/or laboratory parameters to monitor the effectiveness of the procedure and enlist criteria for completion/discontinuation. The urgency of the procedure (emergency, urgent, or routine) must be delineated while planning for plasmapheresis. These holistic goals can ensure the effectiveness and reduce complications of plasmapheresis in clinical settings.
[1] | Kaplan AA, Therapeutic plasma exchange: core curriculum 2008. American journal of kidney diseases : the official journal of the National Kidney Foundation. 2008 Dec; [PubMed PMID: 18562061] |
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[3] | Gerhardt RE,Ntoso KA,Koethe JD,Lodge S,Wolf CJ, Acute plasma separation with hemodialysis equipment. Journal of the American Society of Nephrology : JASN. 1992 Mar; [PubMed PMID: 1627768] |
[4] | Siami GA,Siami FS, Membrane plasmapheresis in the United States: a review over the last 20 years. Therapeutic apheresis : official journal of the International Society for Apheresis and the Japanese Society for Apheresis. 2001 Aug; [PubMed PMID: 11724518] |
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[6] | Pham HP,Staley EM,Schwartz J, Therapeutic plasma exchange - A brief review of indications, urgency, schedule, and technical aspects. Transfusion and apheresis science : official journal of the World Apheresis Association : official journal of the European Society for Haemapheresis. 2019 Apr 18; [PubMed PMID: 31085053] |
[7] | Mokrzycki MH,Kaplan AA, Therapeutic plasma exchange: complications and management. American journal of kidney diseases : the official journal of the National Kidney Foundation. 1994 Jun; [PubMed PMID: 8203364] |
[8] | Owen HG,Brecher ME, Atypical reactions associated with use of angiotensin-converting enzyme inhibitors and apheresis. Transfusion. 1994 Oct; [PubMed PMID: 7940662] |
[9] | Nguyen TC,Kiss JE,Goldman JR,Carcillo JA, The role of plasmapheresis in critical illness. Critical care clinics. 2012 Jul [PubMed PMID: 22713617] |
[10] | Szczepiorkowski ZM,Winters JL,Bandarenko N,Kim HC,Linenberger ML,Marques MB,Sarode R,Schwartz J,Weinstein R,Shaz BH, 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. 2010 [PubMed PMID: 20568098] |