2. DEFINITION
Apheresis is derived from a greek word
meaning “to take away”
Technique in which whole blood is
withdrawn – separated into its components –
desired component is retained and remaining
constituents are returned to donor
3. MECHANISM OF ACTION
Large-bore intravenous catheter is connected to
spinning centrifuge bowl
Whole blood collected from donor/ patient into
the centrifuge bowl
More dense elements like RBCs settle to the
bottom – then WBC – Platelets – and plasma on
the top
4.
5.
6. METHODOLOGY
1. Centrifugation method – separation is by density
2. Membrane filtration technique
Centrifugation method is most commonly used
7. TYPES OF CENTRIFUGATION
METHOD
1. Intermittent flow centrifugation (IFC) –
Performed in cycles ( known as passes)
Blood is collected from an individual
to prevent clotting , anticoagulant added to tubing
8. blood pumped into centrifuge bowl through inlet
port
bowl rotates and components separated according
to specific gravity
RBCs packed against outer rim of bowl(greatest
density)
followed by WBCs, platelets and plasma
9. separated components flow from bowl through outlet
port into separate collection bags
undesired components are diverted into reinfusion
bag and returned to the individual
reinfusion completes one cycle
Cycles are repeated until the desired quantity of
product is obtained (eg – plateletpheresis usually
takes 6-8 cycles to collect a therapeutic dose)
10. IFC can be done –
a. With 1 venepuncture (one arm procedure) –
blood is withdrawn and reinfused through the
same needle
b. With 2 venepuncture (2 arm procedure) – one
for phlebotomy and 1 for reinfusion
11. 2. Continuous flow centrifugation(CFC) –
It withdraws , process and return the blood to
individual simultaneously
This is in contrast to IFC procedure , which
completes a cycle before beginning a new one
Always done with 2 venepuncture sites
ADV- low extracorporeal blood volume is used
– so useful in elderly and children
12. MEMBRANE FILTRATION
TECHNIQUE
Blood that passes over membranes with specific
pore sizes allows passage of plasma through
membrane while cellular portion passes over it
Limited to only plasma collection
13. GUIDELINES FOR THERAPEUTIC
HEMAPHERESIS BY AMERICAN
SOCIETY OF APHERESIS
1. CATEGORY 1 – Efficacy demonstrated
apheresis as primary therapy
a. Hyperviscosity
b. TTP
c. GBS
d. Cryoglobulinemia
e. Myasthenia gravis
f. CTCL
14. 2. CATEGORY 2 – sufficient evidence to support
efficacy but only on adjunctive basis
a. SLE
b. HUS
c. RPGN
d. Coagulation factor inhibitors
e. Cold agglutinin hemolytic anemia
3. CATEGORY 3 - inconclusive evidence for
efficacy
4. CATEGORY 4 – lack of efficacy in controlled
trials
15. APHERESIS PROCEDURAL
ELEMEMTS
1. Venous access
2. Replacement fluid
3. Normal constituents removed
4. Anticoagulation
5. Patient history and medication
6. Frequency and number of procedures
7. Complications
16. VENOUS ACCESS
Requires large bore venous catheters to sustain
a flow rate of 50-100ml/min
Location – Peripheral – anticubital
Central – femoral/subclavian/jugular
17. REPLACEMEMENT FLUID
Required in therapeutic plasmapheresis
Must be FDA approved for use with blood
products – get mixed with RBCs before the return
phase
1.Crystalloids – 0.9% NS
2.Colloids – 5% Normal serum albumin (NSA)
FFP
HES(hydroxy ethyl starch)
18. NS provides less oncotic pressure than plasma ,
so 2-3 times the volume removed should be
replaced
Mixtures of NSA and NS has also been used
FFP is especially recommended in case of TTP
19.
20. NORMAL CONSTITUENTS
REMOVED
Coagulation factors – replaced in 2-3 days after
exchange
Measure PT/APTT every 2-3 days rather than
daily
Platelets – 25-30% loss per procedure
Endogenous synthesis replaces in 2-4 days
21. ANTICOAGULATION
1. Citrate based – a. ACD-A(acid citrate
dextrose- adenine) –MC used
b. Trisodium citrate – used
with leukapheresis
2. Heparin
3. Combination of ACD-A and heparin
22. Citrate binds with ionised calcium and blocks
calcium-dependent clotting reactions
S/E – hypocalcemia – so addition of calcium
with replacement solution can reduce incidence of
hypocalcemia
Heparin prevents conversion of prothrombin to
thrombin
S/E -Heparin results in systemic anticoagulation
So, low amount of heparin + ACD-A is an
effective anticoagulant
23.
24. PATIENT HISTORY AND
MEDICATION
Certain medications like antibiotic and
anticoagulant are removed during aphereis – so
should be given immediately after procedure
Should avoid ACE inhibitors upto 48hrs after
apheresis
26. ACE inh causes – vasodilatation
Apheresis – causes activation of bradykinin in
extracorporeal circuit – potent vasodilator –
profound hypotension
If ACE inh given – further hypotension
27. Use of apheresis technique is divided into 2 –
1. Component collection
2. Therapeutic procedure
2 types of apheresis-
1. Cytapheresis (leucapheresis, plateletpheresis
and erythrocytapheresis)
2. Plasmapheresis
28. PLATELETPHERESIS
COMPONENT COLLECTION
Indication – Bleeding – secondary to
thrombocytopenia or platelet dysfunction
Platelet transfusion
By platelet concentrates
harvested from routine
whole blood
donations(RDP)
By apheresis – Platelet
yield is related to donor’s
initial Platelet count (SDP)
29. Donor’s PC should be > 1.5 lakhs
If it’s the 1st donation or if 4 wks have elapsed
since prior platelet donation – a PC is not reqd
If platelet donation done in <4wks – PC reqd
In apheresis product – Number of platelets (3 *
10^11 in about 300ml ) is equivalent to 6-10
random donor platelets
In case of emergency can donate again after 3
days
30. Must not have taken NSAIDs or Aspirin within
last 48 hrs
Takes about 45-90 mins
Approved for 5 days storage at 20-24°C with
continuous gentle agitation
At the end of storage period – the pH should be ≥
6.2
If RBC contamination in product is negligible
(<2ml) – compatibility testing not reqd
31. THERAPEUTIC PLATELETPHERESIS
Indications -
1. For management of patients with symptomatic
thrombocythemia
2. For those who cant tolerate drug therapy like
hydroxyurea and anagrelide
3. In polycythemia vera
With each procedure of TP – 50% reduction in PC
32. In pregnancy with thrombocythemia – drug
therapy is C/I – so TP is the preferred treatment
for rapid lowering of PC to prevent placental
infarction and fetal death
33. LEUKAPHERESIS
COMPONENT COLLECTION
Indication –
1. Severe neutropenia
2. Patients with infection unresponsive to
traditional therapy
Sedimenting agents like HES allows better
separation of granulocytes from RBCs
34. <2% of total granulocytes in body are present in
circulation – corticosteroids use in donor before
collection can increase number of circulating
granulocytes
Use of recombinant G-CSF and GM-CSF in
donors – cause increase in collection of
granulocytes(upto 1* )
10^11
Current standard dose is ≥1* 10^10
35. Shelf life is 24hrs at 20-24°C but s/b transfused
as soon as possible
Due to large no. of lymphocytes present – must
be irradiated to prevent GVHD (function of
granulocytes is not affected by irradiation)
If RBC contamination >2ml – ABO compability
testing reqd
36. THERAPEUTIC LEUCOCYTAPHERESIS
Indication –
1. To deplete malignant leucocytes in both acute
and chronic leukemias – to prevent/treat
leucostatic syndrome wherein
pulmonary/cerebral dysfunction may develop
once TLC is >1 lakhs/cumm in AML or > 3
lakhs/cumm in CML
2. Leukemic phase of cutaneous T cell lymphoma
(sezary syndrome)
37. ERYTHROCYTAPHERESIS
COMPONENT COLLECTION
done in 2 ways
2 units of RBCs
In such a case, donor must
wait for 16 weeks before
next RBC donation
1 unit of RBC collected
concurrently with
plasma/platelets
38. Donor criteria –
For females – 5’5” height
≥ 150 pounds weight
hematocrit level of 40%
For males – 5’1” height
≥ 130 pounds weight
hematocrit - 40%
39. THERAPEUTIC ERYTHROCYTAPHERESIS
Its an exchange procedure
MC used in – 1. Sickle cell disease – during
severe crisis such as stroke, acute chest syndrome,
priapism and cholestasis
Exchanged with RBC containing ≥ 70% HbA
2. In parasitic infection – severe falciparum
malaria and babesiosis – to lower parasite load
40. PLASMAPHERESIS
COMPONENT COLLECTION
Indication – To collect immune plasma from
donors with increased concentration of certain
plasma immunoglobins
RBCs must be returned within 2 hrs of
phlebotomy
RBC loss s/n/b > 25ml/week
41. Amount of blood processed at one time s/n/b
>500ml – not >1000 ml in 48 hrs – and not >2000
ml in 7 day period
42. THERAPEUTIC PLASMAPHERESIS
Purpose is to remove offending agent in plasma
causing clinical symptoms
Replacement fluid must be given
Factors removed by plasmapheresis –
1. Immune complexes (in SLE)
2. AutoAbs or alloAbs (F-VIII inh)
43. 4. Abs causing hyperviscosity (in Waldenstrom’s
macroglobulinemia
5. Protein bound toxins
6. Lipoproteins
7. Platelet aggregating factors (in TTP)
44. IMMUNOADSORPTION
Method in which a specific ligand binds to
insoluble matrix in a column
Plasma is then perfused over the column
Selective removal of pathogenetic substance and
return of patient’s own plasma
45. ADSORBENT SUBSTANCE REMOVED APPLICATION
Charcoal Bile acids Cholestasis
A and B Ags Anti-A and Anti-B Transplantation
Anti-LDL LDL hypercholesterolemia
DNA ANA, Immune complexes SLE
Protein A(styphylococcal) IgG, Immune complexes ITP, HUS
46. PHOTOPHERESIS
FDA approved for Cutaneous T-cell lymphoma
Patient is treated with drug psoralen
It binds to DNA of all nucleated cells
Leucocytapheresis done and WBCs exposed to UV-A
light
47. this activates psoralen and prevents replication
These treated cells are then returned to patient
Also indicated in – scleroderma, RA, Acute and
chronic GVHD
50. IMPORTANT POINTS TO REMEMBER
In apheresis procedure, blood is withdrawn from
donor/patient – separated into components – one or
more components are retained – remaining
constituents combined and returned back to the
individual
Apheresis by IFC – requires only one
venepuncture site
51. Apheresis by CFC – requires 2 venepuncture
site – withdrawal and return of blood occurs
simultaneous
CFC has an advantage of lower extracorporeal
volume
MC anticoagulant used is - ACD-A
In therapeutic plasmapheresis – replacement
fluid used are – NS, NSA, HES and FFP
52. FFP especially in case of TTP
Granulocyte concentrates should contain a
minimum of 1 * 10^10 granulocytes
Plateletpheresis products should contain a
minimum of 3 * 10^11 platelets , an equivalent of 6-
10 random platelet concentrates
53. REFERENCES
1. Modern blood banking and tranfusion practices
– Denise M. Harmening
2. Recent advances in hematology
3. Various internet sources