Clinical Use of Apheresis (BSH 2015)
Plasma Exchange
SD-FFP for TMA’s, otherwise 4.5% HAS
SD-FFP due to anticipated large total volumes of FFP so want to reduce TTI risk.
SD-FFP also contains some fibrinogen, making hypofibrinogenaemia less likely.
Indications
Disease caused by pathogenic antibodies or other macromolecules found in the plasma
TTP / aHUS
Cryoglobulinaemia
Waldenstroms with symptomatic hyperviscosity
Non-haem - Myasthenia Gravis, Guillain-Barre, Anti-GBM disease, ANCA-vasculitis, ABO-incompatible living donor renal transplant, HLA donor specific antibody rejection in renal transplant, CIDP
Technical Aspects
Aim 1-1.5 plasma volumes exchanged per session
TTP regimen – daily 1.5 plasma vol exchange until platelet count normal for 3 days, then wean down.
Typically centrifugation or filtration system (addenbrookes use centrifugation)
Newer column-based extracorporeal immunoadsorption techniques more rapid effect
SE: Hypofibrinogenaemia
Red Cell Apheresis
Indications
Primarily sickle cell disease – ACS, stroke (acute, 1o or 2o prevention), pre-op
Also used in severe malaria and erroneous Rh D+ blood transfusion to Rh D- woman.
Also considered in polycythaemia – isovolaemic haemoreduction by erythrocytopheresis
Advantages over top-up transfusion
Faster reduction in HbS in acute setting
Reduced frequency of treatments for patient on chronic programs
Reduced iron loading
Top up should not be used where patients Hb is within the normal range
Technical Aspects
Red cell units should be ABO compatible, Rh and Kell compatible, HbS-
Ideally RBC less <8 days old —> longer lasting reduction in HbS, less risk of hyperkalaemia
Typically 8-10 RBC units required to maintain HbS <30% in chronic Ex program
Extracorporeal Photopheresis (ECP)
Collect 5% of patient’s mononuclear cells, expose them to UVA and psoralen and then re-infuse into patient.
Indications
Cutaneous T-cell Lymphoma, Mycosis fungoides / Sezary Syn
Chronic GVHD – 2nd line treatment for skin, mucosal and liver chronic GVHD
Acute GVHD – 2nd line
Technical Aspects
Can use an open or closed system – open gives higher cell dose but risk of infection
Cytoreductive Apheresis (Leukopheresis / Thrombocytapheresis)
Indications
Cytoreduction in leukaemia / MPN with WBC >100 and clinical hyperviscosity
Must be used in combination early initiation of chemotherapy
NOT to be used in APML as worsen coagulopathy
Thrombocytapheresis exists, and has been used occasionally in MPN.
Cellular Therapy Product Collection by Apheresis
Indications
Stem cell collection in Auto and Allograft
T-cell collection for DLI
Technical Aspects
Donors for allograft should be mobilized by GCSF alone
Autograft patients may use GCSF + Chemotherapy. Plerixafor is a 2nd line option
CD34+ count should be assessed by flow cytometry prior to starting apheresis to ensure adequate mobilization. Most centres use cut-off of CD34+ cells >10ul-1.
2-3 blood volumes are processed for stem cell collection
Patient Management
Pre-Apheresis Care
Written informed consent
Rationale, alternative options, explanation of procedure, serious and frequent complications, use of blood products
Clinical assessment of patient
Psychological issues, General health, Haemodynamic stability, Adequate vascular access, Lifestyle of stem cell donors (for TTI risks)
Laboratory investigation
FBC, biochemistry, fibrinogen, microbiology screening if stem cell donor
Prepare an apheresis treatment plan specific for patient
During the procedure
Omit 1 prior dose of ACEI to avoid vasovagal
With exception of IV calcium to correct hypocalcaemia, no meds should be administered during procedure
Continuous monitoring by trained healthcare professional throughout procedure
Post-treatment care
Contact card for patient
Written information about any blood products they received
Complications
More Common
Citrate-related hypocalcaemia
Vasovagal syncope / pre-syncope
Allergic reactions
Albumin-bound drugs are removed by plasma exchange
Less Common
Dilutional coagulopathy
Type II HIT
Line-related thrombosis
Apheresis Service Management
Apheresis service requires
An apheresis lead
Trained staff with regular competency assessment
Adherence to JACIE standards if transplant centre
(Joint Accreditation Committee – ISCT & EMBT)
Standard Operating Procedures
Local Guideline
Good transfusion laboratory support