Apheresis (Immunohematology)
plasma
Membrane filtration technology is an alternative method for _____ collection only
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 4. Clinical applications should be based on approved protocol.
Name three of the four indication categories for TA.
contains less than 5 x 10^6 WBCs per unit
If a unit is successfully leukoreduced, what is the acceptable WBC?
Allergic reactions to the foreign component - for example, the donor may have consumed a allergenic food before donating
In TPE procedures where FFP or albumin is transfused to the patient, what is a concern?
30-60%
Leukaphereses is used to reduce WBC count by ______% (range)
100,000
Leukocytosis is defined as a WBC or circulating blast count of >______/μL
hemolysis (observe returning line)
A patient could have fragile RBC membranes. What is a concern for them during apheresis?
1 - 1.5
Because of the diminishing effect of increased plasma removal, it is recommended that approximately ______ (range) plasma volumes be exchanged per procedure.
1. Infection for 24 to 48 hours that is unresponsive to treatment 2. Myeloid hypoplasia of the bone marrow 3. Chance for bone marrow recovery (reversal)
Criteria for a granulocyte transfusion: 1. Infection for 24 to 48 hours that is (responsive/unresponsive) to treatment 2. Myeloid (hypoplasia/hyperplasia) of the bone marrow 3. (Chance/No chance) for bone marrow recovery
The patient could have a hematologic malignancy. Apheresis could be used to remove excess WBCs
Describe a reason a patient may have a therapeutic apheresis procedure?
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 (or constituent) is returned to the individual.
Describe what apheresis is.
5.5× 10^10
Each unit of platelets from whole blood (RDPs) must contain at least ________ platelets
Acid citrate dextrose is given - this anticoagulant will be introduced to the patient where it will bind calcium. This can cause temporary inhibition of coagulation in the donor.
Effect of Anticoagulation: What anticoagulant is used to prevent anticoagulation in the machine? How does the addition of the anticoagulant affect the donor?
platelets that were sequestered in the spleen are released
Effects of cellular loss: When platelets are apheresed out, what happens to the donor in the following days?
As a component is removed from apheresis fluid, that is also being lost by the donor. Without infusing donor with additional fluid, donor may experience hypotension and an increased heart rate. Vasovagal reactions can occur.
Effects of fluid shift: How do apheresis volume changes affect the donor? What are some neurological effects?
thrombotic thrombocytopenic purpura (TTP) or hemolytic uremic syndrome (HUS)
FFP is only recommended as a replacement fluid in what patients? (x2)
The centrifugation separates items based on specific gravity or weight.
How are components separated out in apheresis?
50-60%
The concentration of most plasma substances is reduced by ______% (range) after one standard plasmapheresis treatment
RBC loss no greater than 25 mL per week
The goal of plasma donation is to have a RBC loss of no more than what?
It changes the centrifuge speed and diameter
The instrument allows you to select a specific constituent to be isolated. What does the instrument do to specifically isolate that component?
15
The patient's extracorporeal blood volume (ECV) should be <______% of the total blood volume (TBV) in order to minimize the risk of hypovolemia. This is calculated by patient
Anticoagulants are added, which can alter the fluid to cell volume balance. Cellular loss will also change that.
There can be some impact to the donor as components are reinfused.
Continuous flow centrifugation (CFC)
This method of apheresis has blood withdrawal, processing, and reinfusion performed simultaneously. This requires two venipuncture sites.
Intermittent Flow Centrifugation (IFE)
This method of apheresis processes blood in batches, reinfusing blood before drawing more. This can use one or two needles.
20,000 to 60,000/μL
Transfusing an adult patient with a plateletpheresis unit should increase their platelet count by what?
Every 16 weeks (If the person donated one RBC and one plasma and/or platelet collected, must wait 56 days prior to donating another red cell product)
How often can a person donate Double Red Cells (Power red)?
Every 2 days (not more than two times in 7 days, no more than 24 times per 12-month period)
How often can a person donate a single unit of platelets?
Every 7 days
How often can a person donate double or triple units of platelets?
Every 2 days, no more than two times in 7 days
How often can a person who frequently donates plasma donate?
Every 4 weeks (no more than 13 times/year)
How often can a person who infrequently donates plasma donate?
Every 2 days
How often can granulocytes be donated?
In some cases, an oral calcium tablet may be given to the donor. Anticoagulants can lower the donor's body temperature, so they are also given blankets.
How can we mitigate the effects of anticoagulants in the donor?
Aspirin = 48 hours. Antiplatelets = up to 14 days
How long must a person defer from PLT donation after taking aspirin? Other antiplatelet medications?
10.5
Per AABB Standards, the extracorporeal blood volume should not exceed _____ mL per kg of body weight
30-60%
Plateletpheresis can be used to treat thrombocythemia with related symptoms. Plateletpheresis reduces count by ______% (range)
Therapeutic Plasma Exchange (TPE)
Removal and retention of the plasma, with return of all cellular components. Effective therapeutic tool for removal of IgM antibodies.
Erythrocytapheresis
Removes a large quantity of RBCs from the patient and returns the patient's plasma and platelets with compatible allogeneic donor RBCs.
It alters the function of lymphocytes. FDA approved for the treatment of cutaneous T-cell lymphoma. May also be used for GvHD.
Utilizes leukapheresis to collect the buffy coat layer from whole blood. The buffy coat is treated with 8-methoxypsoralen (8-MOP) and exposed to ultraviolet A (UVA) light before reinfusion. What does this do?
Give supplemental calcium
What can be done to prevent citrate toxicity in a patient?
1) Staphylococcal protein A - removes IgG 2) Charcoal - removes bile salts 3) Polymyxin B - removes endotoxin 4) Cellulose acetate - removes granulocytes
What do the following materials remove from plasma in immunoadsorption? 1) Staphylococcal protein A 2) Charcoal 3) Polymyxin B 4) Cellulose acetate
Saline is infused
What is done for people during a double red cell donation to prevent hypovolemia?
12 L maximum (14.4 L for donors over 175 lb) allowed per year
What is the maximum amount of plasma that a person can donate over the course of a year (according to the FDA)?
40% -> tested by quantitative method
What is the minimum HCT requirement to donate double red cells (Power red)?
≥150, 000/μL
What is the minimum PLT count for a person to qualify for platelet apheresis donation?
minimum of 3 × 10^11 platelets.
What is the minimum PLT count for a successful plateletpheresis unit? (Same as a successful dose of pooled platelets for adults)
1 x 10^10 granulocytes per day, irradiated
What is the minimum therapeutic dose for granulocytes in a patient?
Sickle cell disease. Other uses include removal of incompatible cells
What is the most common clinical use of erythrocytapheresis?
A) 5% human serum albumin. Use of FFP is reserved for treatment of thrombotic thrombocytopenic purpura (TTP)
What is the most common fluid replacement solution in apheresis? A) 5% human serum albumin B) FFP C) Cryo-reduced plasma D) Normal saline
Blood warmers and blankets
What is used to prevent hypothermia?
Adequate vascular access is mandatory. The patient must have adequate veins at two sites capable of accommodating a 16- to 18-gauge needle
What physical requirement is needed to do therapeutic apheresis?
D) ASFA - American Society for Apheresis
Which of these organizations oversees therapeutic apheresis therapies? A) FDA B) AABB C) CBER D) ASFA
A patient with neutropenia from aggressive chemo, Neutropenic neonates with sepsis, or other similar situations
Who would benefit from a granulocyte transfusion? (Due to the risks and difficulties, it is rarely done)
Separation chamber uses an asymmetric design to minimize contamination from RBCs and WBCs during collection procedure
Why are the centrifugation chambers of apheresis instruments asymmetrical?
Immunoadsorption/Selective Absorption
a method in which a specific ligand is bound to an insoluble matrix in a column or filter. When blood flows past the matrix, a pathogenic substance is adsorbed and removed
