Therapeutic Apheresis Flashcards
who publishes guidelines and recommendations for use of therapeutic apheresis in clinical practice?
American Society for Apheresis
who provides standards for voluntary compliance of therapeutic apheresis?
AABB
what standard defines regulations that govern apheresis activities for donors?
5.5 and 5.6
donor requirements for infrequenct plasmapheresis
collected for direct transfusion; minimum 4 weeks between donations
donor requirements for frequent plasmapheresis
minimum 2 day interval between donations
maximum 2 donations within 7 day period
limits to max volume removed per weight
max red cell loss 25 mL/week
what is source plasma?
plasma from serial donors, not used for direct transfusion
plateletpheresis donor requirements
meet allogeneic whole blood donor requirements
meet apheresis requirements
starting platelet count >150,000/uL
no aspirin within 48 hours of donation
plateletpheresis storage
5 day shelf life at 20-24C with gentle agitation; 4 hours open system
plateletpheresis donor requirements
minimum 8 weeks from whole blood donation
minimum 2 days between donations
maximum 2 donations within 7 day period
maximum 24 donations in 12 month period
how long after whole blood donation can a donor donate plateletpheresis?
8 weeks
how long after plateletpheresis can another single platelet be donated?
2 days
how many plateletpheresis donations are allowed in a 7 day period?
2
one plateletpheresis is equivalent in platelet count to how many platelet concentrates?
6-8
what is minimum platelet count per apheresis unit?
3x10^11
plateletpheresis must be suspended in enough plasma to maintain what pH?
6.2
donor height and weight requirement for red cell apheresis
must meet requirement of manufacturer of equipment used to collect apheresis
minimum age for red cell apheresis
17 years old
donor hematocrit for red cell apheresis
.40% male and female
donation interval between red cell apheresis units
16 weeks between donations
indications for leukapheresis
septicemia
severe neutropenia
why is hydroxyethyl starch added to apheresis circuit during leukapheresis?
promotes rouleaux to allow better separation of red cells and white cells
what is given to donors 8-12 hours before leukapheresis procedure to increase granulocyte harvest?
corticosteroids to move granulocytes into circulation
G-CSF to stimulate production of granulocytes
are granulocyte units crossmatched?
yes due to RBC contamination
are granulocytes leukoreduced?
no
are granulocytes irradiated?
yes
granulocyte yield of leukapheresis
> 1x10^10
leukapheresis storage
20-24C without agitation up to 24 hours after collection
how long can granulocytes be stored after collection?
24 hours
goal of therapeutic apheresis
treat certain conditions/diseases through removal of blood compnents/pathologic substances
single blood volume therapeutic apheresis will get rid of what volume of pathologic substance?
two-thirds
apheresis mode: removal of whole blood –> centrifuge –> plasma taken off and discarded –> red cells re-infused along with replacement fluid
manual
apheresis mode: specialized device controls rate which blood is withdrawn, anticoagulation, separation, replacement fluids, and blood return. Separation occurs through centrifugation and filtration
automated
apheresis mode: rotating channel, resulting in layers of plasma, platelets, leukocytes or red cells that can be removed selectively. removed component is diverted into separate bag; remaining components along with replacement fluid is re-infused back into patient
continuous flow
apheresis mode: whole blood withdrawn, extracorporeal blood component processed, centrifugation, selected component taken off, remaining components along with replacement fluid re-infused back into patient
intermittent centrifugation
apheresis mode: continuous flow operation; whole blood processed through microporous filter, plasma passes through, red cells retained. hollow filtration used to wash/remove immunoglobulins
filtration device
apheresis mode: whole blood passes through a medium of high affinity for specific components, effluent returned to patient
selective adorption
most commonly used anticoagulant in apheresis
citrate
why is calcium administered during apheresis return procedure?
citrate binds calcium and causes hypocalcemia
category I indications for apheresis
apheresis is standard, primary therapy
category II indication for apheresis
apheresis is acceptable, supportive therapy
category III indication for apheresis
apheresis is not well established, individualized therapy
category IV indication for apheresis
apheresis is ineffective or harmful
main indication for therapeutic plasma exchange
hyperviscosity
disease states associated with hyperviscosity needing TPE
TTP, Waldenstrom’s macroglobulinemia, Myasthenia gravis, Guillain-Barre, Goodpastures syndrome, solid organ transplant
replacement fluids used with TPE
5% albumin, 5% albumin and normal saline, donor plasma, cryopoor plasma
how many TPE procedures are usually required to remove 90% of IgG antibodies?
~5 procedures of 1.5 blood volumes
how many TPE procedures are usually required to remove 90% of IgM antibody?
2-3
rare blood disorder characterized by clotting in small blood vessels of the body resulting in low platelet count
thrombotic thrombocytopenic purpura
TTP pentad of symptoms
microangiopathic hemolytic anemia thrombocytopenic purpura neurologic abnormalities fever renal disease
mechanism of TTP
IgG antibody directed against ADAMTS13 enzyme
what happens without ADAMTS13 in TTP?
large multimers of vWF accumulate and cause red blood cell hemolysis, thrombocytopenia, and organ damage
indications for red cell exchange
sickle cell, hereditary hemochromatosis, polycythemia vera, babesiosis, severe malaria
most common use of red cell exchange
sickle cell patients experiencing acute crisis
most common indication for leukapheresis
hyperviscosity in acute leukemia
specialized procedure in which buffy coat layer of blood is collected from whole blood, treated with 8-methoxypsoralen, exposed to UV light, reinfused back into patient
photopheresis
effect of photopheresis
causes crosslinking of leukocyte DNA preventing replication and induces apoptosis
indications for photopheresis
cardiac allograft rejection lung allograft rejection cutaneous T-cell lymphoma GVHD systemic fibrosis pemphigus vulgaris scleroderma
indications for selective adsorption apheresis
selective removal of LDL refractory rheumatoid arthritis polyneuropathies (IgG/IgA or IgM) lupus (removal of anti-DNA) myasthenia gravis
reactions to therapeutic apheresis
tingling, hypotension, hives, nausea, shivering, flushing, fainting, vertigo, arrhythmia, abdominal pain, anaphylaxis
most common adverse effect of apheresis
symptomatic hypocalcemia (perioral and digital paresthesias) from infusion of citrate with returned blood
most common reaction with plasma replacement
allergic reactions
