Table of Contents
Definition / general | Indications | ASFA guidelines | Examples of TPE category I indications per 2019 ASFA guidelines (not comprehensive) | Vascular access | Anticoagulation | Replacement fluid | TPE removes plasma | Potential adverse events | Clinical documentation in the patient’s medical record | Additional references | Board review style question #1 | Board review style answer #1 | Board review style question #2 | Board review style answer #2Cite this page: Godbey EA. Therapeutic plasma exchange (TPE). PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/transfusionmedtherapeuticplasmaexchange.html. Accessed December 2nd, 2024.
Definition / general
- Automated instrument removes whole blood from patient, separates and removes plasma, returns remainder of blood along with replacement fluid
- Instrument separation method: centrifugation (most common method in U.S.) or membrane filtration
- Volume treated: most commonly 1 - 1.5 plasma volumes
Indications
- In general, goal is to remove pathogenic substances present in plasma to mitigate disease processes
- American Society for Apheresis (ASFA) guidelines were most recently updated in 2019 (J Clin Apher 2019;34:171)
ASFA guidelines
- Published every 3 years
- For each indication, ASFA provides
- Category: I - IV (description of the role of apheresis in treatment of the indication)
- I: “Disorders for which apheresis is accepted as first-line therapy, either as a primary standalone treatment or in conjunction with other modes of treatment.”
- II: “Disorders for which apheresis is accepted as second-line therapy, either as a standalone treatment or in conjunction with other modes of treatment”
- III: “Optimum role of apheresis therapy is not established. Decision making should be individualized.”
- IV: “Disorders in which published evidence demonstrates or suggests apheresis to be ineffective or harmful. IRB approval is desirable if apheresis treatment is undertaken in these circumstances.”
- Grade: 1A - 2C (a reflection of the evidence used to assign the category)
- Background information about disease
- Practical guidance: replacement fluid, number of procedures, frequency of procedures, volume to treat
- Category: I - IV (description of the role of apheresis in treatment of the indication)
- Reference: J Clin Apher 2019;34:171
Examples of TPE category I indications per 2019 ASFA guidelines (not comprehensive)
- Catastrophic antiphospholipid syndrome
- Chronic inflammatory demyelinating polyradiculoneuropathy
- Focal segmental glomerulosclerosis recurrent in kidney transplant
- Myasthenia gravis acute, short term treatment (long term treatment is category II)
- Antibody mediated rejection following ABO compatible renal transplant (antibody mediated rejection following ABO incompatible renal transplant is category II)
- Thrombotic thrombocytopenic purpura
- Wilson disease, fulminant
- Reference (includes all indications): J Clin Apher 2019;34:171
Vascular access
- Access must accommodate high flow rates
- Peripheral veins, central venous catheter, ports, fistula, AV graft are options; choice will depend on urgency and frequency of plasma exchange needed
Anticoagulation
- Citrate or heparin
- Use of supplemental calcium with citrate anticoagulation varies by institution (some administer calcium to every patient, some according to patient ionized calcium values or patient symptoms of hypocalcemia)
Replacement fluid
- Typically, albumin or donor plasma (or a combination of these, for example, half albumin followed by half plasma)
- See ASFA guidelines for indication specific recommendations (J Clin Apher 2019;34:171)
- Plasma with coagulopathy, bleeding, peri-invasive procedure; always use plasma for TTP
- Typically, 1 - 1.5 plasma volumes are exchanged per TPE procedure; the Optia instrument can calculate this volume based on patient specific data
- One plasma volume = total blood volume x (1 - hematocrit)
TPE removes plasma
- Includes not only potential pathogenic substances but also normal plasma contents such as coagulation factors
- For a 1 plasma volume exchange using albumin as replacement fluid, coagulation factors may decrease by 25 - 50% and are expected to recover 80 - 100% by 48 hours; fibrinogen is expected to decrease by 63% and recover 65% by 48 hours; fibrinogen may need to be supplemented in some patients
- Can remove medications (especially those that are highly protein bound, small volume of distribution); for example, IVIG and monoclonal antibody medications will be extensively removed by plasma exchange; administration should be postponed until after the procedure
- For an extensive discussion of plasma content changes resulting from TPE, please see Winters: Apheresis: Principles and Practice, Volume 1: Therapeutic Apheresis, 4th Edition, 2020
Potential adverse events
- Associated with anticoagulant: e.g. symptoms of hypocalcemia secondary to citrate
- Associated with concurrent ACE inhibitor use: hypotension
- Associated with extracorporeal volume: e.g. hypotension
- Associated with replacement fluid: e.g. allergic reaction to albumin or plasma
- Associated with vascular access: e.g. infection
- Very rare, death
Clinical documentation in the patient’s medical record
- Note styles and content vary among institutions and among providers, but an example of a brief daily progress note follows:
- Ms. X underwent plasma exchange today for myasthenia gravis (MG) exacerbation. She tolerated the procedure without procedure related side effects. Ms. X reports that her MG symptoms continue to improve.
- Vital signs: temperature 37 C, pulse 74 bpm, BP 137/64 mmHg, RR 20 br/min
- General: appeared comfortable, no acute distress
- Laboratory values: hemoglobin: 11.5 g/dL, PLT: 268x10e9/L, fibrinogen: 194 mg/dL
- Ms. X is a 50 year old female who presented for plasma exchange for myasthenia gravis exacerbation. This was plasma exchange number X out of Y requested. The next procedure is planned for [date]. Further management per neurology.
- Ms. X underwent plasma exchange today for myasthenia gravis (MG) exacerbation. She tolerated the procedure without procedure related side effects. Ms. X reports that her MG symptoms continue to improve.
- Basic information to consider including in notes:
- Initial consult note: indication, ASFA category (if in ASFA guidelines), procedure type, number of planned procedures, anticipated schedule, replacement fluid to be used, volume to be exchanged, referring physician, access, vitals / brief physical, pertinent laboratory values, allergies, medications, past medical history
- Daily procedure notes: indication, procedure type, vitals / brief physical, pertinent laboratory values, interventions and outcome if procedure related side effects occurred, replacement fluid
Additional references
- Balogun: Principles of Apheresis Technology, 7th Edition, 2020
- Shaz: Transfusion Medicine and Hemostasis - Clinical and Laboratory Aspects, 3rd Edition, 2019
- Schwartz: Therapeutic Apheresis - A Handbook, 6th Edition, 2019
- Cohn: Technical Manual, 20th Edition, 2020
- Wu: Apheresis Standard Operating Procedures Manual, 1st Edition, 2019
Board review style question #1
Which of the following entities is considered a category I indication for therapeutic plasma exchange?
- Amyloidosis, systemic
- Autoimmune hemolytic anemia, severe
- Catastrophic antiphospholipid syndrome (CAPS)
- Thyroid storm
Board review style answer #1
C. Catastrophic antiphospholipid syndrome (CAPS)
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Reference: Therapeutic plasma exchange
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Reference: Therapeutic plasma exchange
Board review style question #2
Which of the following entities is considered a category I indication for therapeutic plasma exchange?
- IgA nephropathy (Berger disease)
- Myasthenia gravis (acute, short term treatment)
- Myasthenia gravis (long term treatment)
- PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections) exacerbation
Board review style answer #2
B. Myasthenia gravis (acute, short term treatment)
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Reference: Therapeutic plasma exchange
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Reference: Therapeutic plasma exchange