BB Exam 4: Apheresis
Donor management: effects of anticoagulants
May experience chills (provide blanket) - Possibly give oral calcium tablet (Tums bc increased calcium in it)
Methodology of apheresis - What 4 things it involves
Modern apheresis instruments utilize a computerized control panel, allowing the operator to select the desired component to be collected or removed 1. Onboard optical sensors 2. Disposable equipment - Sterile single tubing sets, bags, and collection chambers 3. Duration 4. Goals - Determine instrument selection (donor or therapy apheresis)
Citrate toxicity adverse effect during apheresis
More common in cytapheresis procedures due to anticoagulated plasma return at a rapid rate - Common in TA procedures (therapeutic) - Prevention: infusion of Ca intravenously or tums
Leukapheresis - patient population - reduces WBC by how much %?
Most commonly in patients with AML (usually AML pts use it) vs ALL - reduces WBC by 30-60%
Immunoadsorption/ selective absorption Staphylococcal protein A
Used in selective adsorption: cell wall component of S. aureus - Affinity for IgG classes 1, 2, and 4 and for IgG immune complexes
Therapeutic plateletpheresis - Used to treat what? - Reduces plt count by how much %?
Used to treat thrombocythemia with related symptoms - Risk of thrombotic or hemorrhagic complications (platelet count exceeds 1,000,000/µL) - Reduces platelet count by 30-60%
Photopheresis
Utilizes leukapheresis to collect the buffy coat layer from WB used for the treatment of cutaneous T cell lymphoma - Treated with 8- methoxypsoralen (8-MOP) - Exposed to ultraviolet A (UVA) light then re-infused
the replacement fluid indicated during plasma exchange for TTP is: a. normal (0.9%) saline b. hydroxyethyl starch (HES) c. FFP d. albumin (5%) human
c. FFP
the most common adverse effect of plateletpheresis is: a. allergic reaction b. hepatitis c. citrate effect
c. citrate effect
What are the two common methods of centrifugation?
Intermittent Flow Centrifugation (IFC): processed in batches (or cycles) - Single- needle procedure with one venipuncture site - Instrument: Haemonetics MCS plus Continuous flow centrifugation (CFC): blood withdrawal, processing, and reinfusion performed simultaneously - Two venipuncture sites, 2-needle procedure - Instruments: COBE spectra, Baxter/Fenwal Amicus
The most common fluid replacement for TPE is _____________
5% human albumin - Use of FFP reserved for treatment of TTP - Cryo-reduced plasma could be alternative
One WB platelet should increase the adult patient's platelet count to:
5,000-10,000/uL in 70 kg pt - Each unit of WB
Platelets are leukoreduced; so they must contain less than __________ WBCs per unit
5.0 x 10^6 /µL
Each unit of platelets from WB (RDPs) must contain at least _____ platelets
5.5 x 10^10 plts
Plasma protein interactions The concentration of most plasma substances is reduced by _____-____% after one standard plasmapheresis treatment
50-60%
If one RBC and one plasma/platelet product are collected, how long must the donor wait to donate another RBC product?
56 days
Apheresis platelets provide the equivalent of __________ units of WB-derived donor platelets
6-8
Frequency of WB donation
8 weeks
The patients extracorporeal blood volume (ECV) should be ______% of the total blood volume (TBV) in order to minimize risk of hypovolemia
<15% - Calculate pts plasma volume (TBV and hemocrit used)
What is the rationale for therapeutic apheresis (TA) based on?
A pathogenic substance exists in the blood that contributes to a disease process or its symptoms - Said substance can be more effectively removed by apheresis than by the body's own mechanisms
Apheresis definition
A procedure where whole blood is removed from the body and passed through an instrument that separates out one or more blood components - The remaining portion is returned to the individual - Performed on patient or blood donor
Effects of anticoagulants - What is the primary anticoag used? - What does this do? - Metabolized where?
Acid citrate dextrose (ACD) is the primarily used anticoagulant - Binds to calcium ions to inhibit Ca-dependent coag cascade - Citrate is metabolized by liver, kidney, and muscles - Previously bound calcium ions are released back into blood stream
Vascular access in therapeutic apheresis
Adequate vascular access is mandatory - Peripheral veins, central veins, or a combination of both The patient must have adequate veins at TWO sites capable of accommodating a 16-18 gauge needle
Membrane filtration technology
Alternative method for plasma collection only - Membrane separators are typically composed of bundles of hollow fibers or flat plate membranes with specific pore sizes - Pores can be sized to prevent the passage of small cellular elements during plasma collection
Therapeutic apheresis is oversought by what organization?
American Society for Apheresis (ASFA)
Separation chamber
Asymmetric design to minimize contamination from RBCs and WBCs during collection procedure
_____ HPC donors have (shorter/longer) period of cytopenia, decreased tranfusion requirements, fewer infectious complications and decreased length of hospitalization
Autologous, shorter
Effects of fluid shifts - What may donor experience? - What 2 reactions can be caused?
Changes in intravascular volume occurs secondary to removal of blood into the extracorporeal circuit (outside of body) - Without infusing donor with additional fluid, donor may experience hypotension and an increased heart rate 1) Hypovolemic reactions 2) Vasovagal reactions
What population is most at risk for hypovolemic (volume depletion) considerations?
Children and elderly individuals
What are most deaths from during therapeutic apheresis?
Circulatory overload (cardiac arrest or arrhythmia) - Or respiratory complications (acute pulmonary edema/adult respiratory distress syndrome)
What type of centrifugation requires two venipuncture sites?
Continuous flow (CFC)
Cytapheresis procedures vs plasmapheresis procedures of TA
Cytapheresis: - selectively removes RBCs, WBCs, and/or PLTs Plasmapheresis: - removes plasma when a pathological substance is found in circulation (increased amount of globulin proteins)
Apheresis methodology Onboard optical sensors
Detect specific plasma-cell or cell-cell interferences/ratios - Divert component to specific bag
Effects of cellular loss Granulocyte donors see a drop in HCT of _____ and PLTs by ____%
Drop in HCT of 3% Drop in PLT of 22%
Frequency of granulocyte donation
Every 2 days
Frequency of plasma (frequent) donation
Every 2 days (no more than 2 times in 7 days)
Frequency of donation for single platelets
Every 2 days (not more than 2 times in 7 days, no more than 24 times per 12- month period)
Frequency of plasma (infrequent) donation
Every 4 weeks (no more than 13 times/year)
Frequency of platelets, double or triple
Every 7 days
Clinical application of photopheresis
FDA approved for treating cutaneous T cell lymphoma - Acute and chronic GVHD. solid organ transplant rejection, and selected immunologically mediated diseases
T/F: granulocytes do not contain a higher yield of WBCs than whole blood
False
Platelet apheresis is essential for what diseases?
Formation of primary plt plug and maintaining normal hemostasis - Thrombocytopenia, chemo, DIC, massive transfusion
In granulocyte donation meds, what are the side effects of the RBC sedimenting agent, hydroxyethyl starch (HES)?
Headaches, peripheral adema - CSF and GF meds prior to transfusion
Combined IFC and CFC
Single platform - Draw/reinfusion (IFC) - Centrifuge (CFC) - Allows for concurrent collection of blood components and leukoreduction - Instrument: Caridian BCT Trima, Baxter/Fenwal Alyx
Separation of blood components is based on ?
Specific gravity or weight of each constituent
FFP recommended only in cases of what?
TTP (thrombocytopenic purpura) or HUS (hemolytic uremic syndrome) - Possibility of disease transmission (HIV and hep)
why are hematopoietic stem cells commonly used prior to HPC collection?
To increase # of circulating stem cells in PB - Anesthesia avoided - Autologous HPC donors have shorter period of cytopenia, decreased transfusion requirements, fewer infectious complications, and decreased hospitalization stay
Why is fluid replacement necessary in therapeutic plasmapheresis?
To maintain appropriate intravascular volume and oncotic pressure
Purposes for plasmapheresis
Transfusion and manufacturing - Divided into frequent and infrequent in donors - RBC loss no greater than 25 mL/week
Leukapheresis is used for ?
Treat patients with hyperleukocytosis - Defined as a WBC or blast count of >100,000/uL
(2)RBC donation
Typically collected as a double unit - 2RBC, double red, or double RBC procedure - Reduces donor exposure for recipient - Used by both autologous and allogeneic - Saline infused during to account or blood loss
Immunoadsorption/ selective absorption Charcoal
Used in selective adsorption - removal of bile acids
Variables for consideration
- Centrifuge speed and diameter - Dwell time of the blood in centrifuge - Type of solutions added: anticoags or sedimenting agents - Cellular content or plasma volume of the patient/donor - Leukoreduction occurs during apheresis process
Adverse effects of apheresis
- Citrate toxicity - Vascular access difficulties (catheter insertion, ports) - Vasovagal reactions (fainting) - Hypovolemia: IFC, single use instrument - Allergic reactions: TPE (FFP and albumin) - Hemolysis: mechanical
What three effects may be impactful on the donor's body when donating for apheresis?
1) Effects of anticoagulation 2) Effects of fluid shifts 3) Effects of cellular loss
Effects of fluid shifts ___ and ___ reactions are involved in fluid shift effects.
1) Hypovolemic (low fluid volume): sympathetic nervous system - Not commonly encountered due to extracorporeal restriction of 10.5 mL/kg 2) Vasovagal: parasympathetic nervous system - Decreased heart rate - Age and gender factors
Bc of TPEs diminishing effect of increased plasma removal, its recommended that ___ to ___ plasma volumes be exchanged/procedure
1-1.5
2 advantages of membrane filtration technology
1. Cell-free product 2. Ability to selectively remove specific plasma proteins
What are the 3 criteria for a granulocyte donation?
1. Infection for 24-48 hours that is unresponsive to treatment 2. Myeloid hypoplasia of bone marrow 3. Chance for bone marrow recovery
What patient populations benefits from granulocyte donations?
1. Neutropenic neonates with sepsis 2. Patients who underwent aggressive chemo (neutropenic)
What are the 4 indication categories for TA?
1. apheresis is standard and acceptable in primary therapy (first-line) or with other therapies 2. generally accepted in a support role or second-line treatment 3. decision making should be individualized (case by case) 4. clinical applications should be based on approved research protocol
Granulocyte apheresis must have a minimum therapeutic dose of _______ granulocytes per day
1.0 x 10^10 grans/day
Per AABB standards, the extracorporeal blood volume should not exceed ______ mL/kg of body weight - Greater in what type of centrifuge?
10.5 mL/kg - Greater in IFC vs CFC (bc CFC continuously going)
What is the maximum L for plasmapheresis allowed/year?
12L or (14.4L for donors over 175lbs)
Frequency of double RBC donation
16 weeks (112 days)
Each apheresis unit of plasma is the volume equivalent of at least ______ whole blood derived plasma units
2
One plateletpheresis unit should increase the adult patient's platelet count to:
20,000-60,000/uL - Increases baseline by this much
Effects of cellular loss Platelet donors have an acute fall of _________% for cellular loss - Greatest in what sex? Considerations?
20-29% - Greater in female donors - Considerations: mobilization of platelets from the spleen (can recover this amount in healthy pts)
Plateletpheresis component is prepared from one donor and must contain a minimum of ______ platelets
3 x 10^11 plts
A pool of 4-6 RDP units will contain roughly _______ platelets
3 x 10^11 plts (this makes it the same as amount in plateletpheresis) - Therapeutric equivalent: unit of single donor plts - PLT count increase similar to plateletperesis
What is the HCT requirement for double RBC donation (2RBC apheresis)?
40% - Quantitative method used to determine hgb and hct levels
Apheresis methodology Duration of procedure
45-120 mins - HPC collection may take longer
How long is an aspirin deferral for plateletpheresis? - What about other antiplt meds?
48 hours - Up to 14 days (2 weeks)
Risk of leukapheresis
Organ dysfunction from formation of microthrombi in pulmonary and cerebral microvasculature
What are the clinical considerations for TPE (therapeutic plasma exchange)?
Overproduction of specific monoclonal antibodies or polyclonal antibodies - Treat Waldenstrom's macroglobulinemia
Immunoadsorption/ selective absorption
Refers to a method in which a specific ligand is bound to an insoluble matrix in a column or filter - Selective removal of the pathogenic substance - Reinfusion of patient's own plasma and cellular components
What is therapeutic plasma exchange (TPE)?
Removal and retention of the plasma, with return of all cellular components - Removal of an offending agent in the plasma - Replacing a normal factor or substance that may be missing/deficient in the patient's plasma
Erythrocytapheresis definition
Removal of RBCs
HPC apheresis definition
Removal of hematopoietic progenitor cells (HPCs) - Also referred to as PBSC (PB stem cells)
Plasmapheresis and plateletpheresis definitions
Removal of plasma - Removal of plts
Leukapheresis definition - Donor vs. patient
Removal of white blood cells (WBCs) - In donors, granulocytes are collected - In patient, removal of granulocytes and possibly lymphs
TPE is an effective tool to:
Remove IgM ABYs
What is the therapeutic goal of RBC exchange (erythrocytapheresis)?
Remove incompatible RBCs from patient's circulation - example: Rh pos RBCs transfused to Rh neg female of childbearing age - Or SSD, malaria, Babesia
Erythrocytapheresis (red cell exchange) - purpose - most commonly used for what pts?
Removes a large number of RBCs from the patient and return the patient's plasma and platelets with compatible allogeneic donor RBCs - Most commonly used to reduce complications of sickle cell disease (reduce hgb S to less than 30%)
Loss of RBCs in apheresis
Varying - Procedures track annual cell losses (required) - Goal: cumulative annual red cell loss for donors is not exceeded
the anticogulant added to blood as it is removed from a donor or patient during an apheresis procedure acts by: a. bidning calcium ions b. increases intracellular potassium c. binding to antithrombin III d. inactivating factor V
a. binding calcium ions
in plasma exchange, the therapeutic effectiveness is: a. greatest w the first plasma volume removed b. affected by the type of replacement fluid used c. enhanced if the unwanted aby is IgG rather than IgM d. independent of the concomitant immunosuppressive therapy
a. greatest w the first plasma volume removed
therapeutic cytapheresis has a primary role in treatment of patients with: a. sickle cell disease and acute chest syndrome b. systemic lupus erythematosus to remove immune complexes c. leukemia to help increase granulocyte production d. mysathenia gravis to increase aby production
a. sickle cell disease and acute chest syndrome
the minimum interval allowed btw plateletpheresis component collection procedures is: a. 1 day b. 2 days c. 7 days d. 8 weeks
b. 2 days
which of the following can be given to an apheresis donor to increase the number of circulating granulocytes? a. DDAVP b. HES c. Immune globulin d. G-CSF
d. G-CSF
Book Questions The most common anticoagulant used for apheresis is: a. heparin b. sodium fluoride c. warfarin d. citrate
d. citrate
Immunoadsorption/ selective absorption Polymyxin B
used in selective adsorption - removal of endotoxin
Immunoadsorption/ selective absorption Cellulose acetate
used in selective adsorption - removal of granulocytes
What is the PLT count minimum for plateletpheresis?
≥150,000/µL - Bc normal patient can bounce back