Apheresis 2

Apheresis Definition

Removing whole blood from the body, separating the desired components via centrifugation, then returning the undesired components to the donor

Apheresis

What does it eliminated?

Disease causing

Unwanted cellular

Plasma constituents from a patient

T/F. Apheresis can be used to harvest stem cells from the peripheral blood of donors and patients.

True, you can avoid bone marrow extraction

Donor apheresis

Apheresis performed on a donor to collect a specific blood component

Therapeutic apheresis

Apheresis performed on a patient to remove a particular blood component for therapeutic purposes

Process of removing plasma via apheresis

Plasmaphersis

Plateletpheresis

Process of removing platelets via apheresis

Process of removing WBC via apheresis

Leukopheresis

Erythrocytapheresis

Process of removing RBCs via apheresis

HPC apheresis

Process of removing hematopoietic progenitor or stem cells via apheresis

Apheresis principle (4)

1. Separation of blood components is based on specific gravity and weight of individual components

2. RBCs at the bottom

3. Plasma portion at top of tube

4. In between the 2 layers is a Buffy coat where WBCs and platelets are located.

Describe how apheresis works when collecting blood from a patient/donor (4)

1. Blood removed from individual and mixed with anticoagulant. Transported directly to a separation device

2. Machine separates components

3. Specific portion is drawn off and separated

4. Remainder mixed and returned to patient/donor

What is the primary anticoagulant in apheresis procedures?

Citrate

Function of citrate

Chelates calcium

Prevents clotting

When is citrate added to the sample to undergo apheresis?

Immediately after blood is drawn but before the sample undergoes centrifugation

Where in the body is citrate metabolized? (3)

Liver

Kidneys

Muscles

What happens as citrate is metabolized?

Calcium is released back into circulation

Due to the decreased calcium when citrate is added, what is released?

Parathyroid hormone (PTH)

What does PTH do? (3)

Increase blood calcium levels via

1. Mobilization of Ca from bone

2. Increased intestinal absorption of Ca

3. Increased reabsorption of Ca by the kidneys

During apheresis procedure, the total volume of components may be greater than that of volume of a whole blood donation.

What can this cause?

How to avoid?

Hypotension due to depletion of intravascular volume

Additional fluids

Hypotension

How does the sympathetic nervous system try to compensate?

Increased cardiac output (heart rate)

Why is hypovolemic reactions uncommon among apheresis donors?

Regulatory restrictions limit the extracorporeal (outside the body) volume to 10.5 ml/kg

Besides loss of volume, how else can hypotension occur via apheresis?

Vasovagal reaction

Vasovagal reaction

What is it?

Parasympathetic NS overrides the output from the sympathetic NS resulting in hypotension and slowing of the heart

Vasovagal reaction via apheresis

Common in (3)

Apheresed donors:

Teenagers more than adults

Female more than men

A platelet donor typically experiences an acute fall in platelet count of _____ following apheresis donation?

20-29%

Drop in females is greater than males

Adverse effects of transient decrease in platelet count?

None have been demonstrated?

After plateapheresis, how long until platelet count is normal?

3 days

During granulocyte pheresis procedure, what is the typical drop of hematocrit and platelet levels?

What causes the drop

Hematocrit= 7%

Platelet= 22%

Due to the loss of the products and dilution effects of volume expansion caused by HES

What is typically lost during each donor apheresis procedure?

RBCs

Using automated system, how are individual components collected via apheresis?

Operator can select specific components

The optical sensors can detect plasma-cell or cell-cell interface and divert the specific component into a collection page

Time of apheresis procedure?

45-120 minutes depending on the procedure

Variables to consider during and apheresis procedure? (4)

Centrifuge diameter and speed

Duration of dwelling time of blood in the centrifuge

Types of solutions added (anticoagulants, sedimenting agents)

Cellular content or plasma volume of the patient or donor

Intermittent Flow Centrifugation

How is blood processed?

In batches or cycles

Intermittent Flow Centrifugation

Describe the process (4)

1. Blood drawn from donor and anticoagulant added

2. Blood centrifuged, components separated based on specific gravities and weight

3. Once separated the pump is reversed and desired component(s) are pumped into a collection bag

4. Undesired are pumped into a rein-fusion bag and returned to the donor

Intermittent Flow Centrifugation

Closed system

Yes, rotary seal is used

Intermittent Flow Centrifugation

Benefit

Requires one venous access

Draw and returned can be achieved through 1 needle

Continuous Flow Centrifugation

What is it?

Process of blood withdrawal, processing, and rein fusion are simultaneously happening

Continuous Flow Centrifugation

Requires

2 ventipuncture sites

Advantage of Intermittent Flow Centrifugation (3)

Smaller equipment

More mobile

One venipuncture

Disadvantages of Intermittent Flow Centrifugation

Extracorporeal blood volume greater (more blood out of the donor at the same time)

Continuous Flow Centrifugation

Advantages

Less citrate reactions

Continuous Flow Centrifugation

Disadvantages

2 venipuncture sites

What type of centrifugation do you want to used with children and elderly?

Continuous flow centrifugation

Membrane Filtration

Made off

Hollow fibers or flat plate with different pore sizes

Membrane Filtration

What is collected?

Cell-free p lasma

Apheresis

Double RBC

16 week deferral

Apheresis

Plasma (frequent)

Every 2 days, no more than twice in 7 days

Apheresis

Plasma (infrequent)

Every 4 weeks- no more than 13 times a year

Apheresis

Platelets-double or triple unit

Every 7 days

Apheresis

Granulocytes

Every 2 days

Before donor apheresis, what must be obtained?

Written consent

Before donor apheresis, what must be describe to the donor? (4)

Procedure

Risks

Testing

Benefits (recipient)

Side effects of apheresis (3)

Hypovolemia

Fainting

Anticoagulant

RBCs collected by apheresis are typically collected as a

Double unit (2RBC)

When 2RBC are collected, what can be returned to the donor?

Plasma Platelets

2RBC

Minimum hematocrit

At least 40% regardless of gender

2RBC

How to determine hematocrit?

Quantitative methods

T/F. You can determine hemoglobin hematocrit via copper sulfate method.

False

Need to be a quantitative method

Double RBC

Deferral period

16 weeks

If 1 RBC, 1 plasma, and/or 1 platelet are collected

Deferral period

56 days (8 weeks)

During RBC apheresis what is used to replace the volume lost?

Saline

During plasmapheresis what components are returned to the donor?

RBC WBC Platelets

Plasmapheresis is equivalent to

2 whole blood plasma units

Plasmapheresis

Uses (4)

1. Specific blood type (such as AB)

2. Donors with high titers of specific antibodies for the production of immune globulins (HBV, CMV, varicella zoster)

3. Prepare Rhogam

4. Prepare IVIG

Plasmapheresis (infrequent donor)

4 weeks, no more than 13 times a year

Plasmapheresis (frequent donor)

Deferral period

2 days, twice within 7 days

Plasmapheresis (frequent donor)

Requirements (2)

Periodic evaluation by a physician and additional testing

Plasmapheresis (frequent donor)

Additional testing (3)

Total protein

Serum protein electrophoresis

Immunoglobulin levels

Plasmapheresis (frequent donor)

RBC loss must not exceed?

25 ml/week

Platelets obtained from apheresis procedure provide the equivalent of

6-8 units of whole blood blood derived platelets (RPD)

Plateletphereis what is collected?

Platelet Small portion of donor plasma

Plateletpheresis

What is returned to the donor?

RBC WBC Most of the plasma

Plateletpheresis

Platelets are resuspended in

Donor plasma

Plateletpheresis

Time frame

45-90 minutes

For plateletpheresis what can be collected concurrently? (2)

Single RBC Single plasma

Donor selection for plateletpheresis requires 2 additional testing

1. Platelet count at least 150,000/uL

2. Must not be taking medications what interfere with platelet function

Donor selection for plateletpheresis requires 2 additional testing

When can this be waived?

Initial platelet pheresis for the donor

If 4 week have relapsed

But platelet count must be evaluated after platelet collection

What medications cause a 48 deferral for collecting platelets? (2)

Aspirin Feldene

What medications cause a 2 week deferral for collecting platelets? (4)

Plavix

Ticlid

Brilinta

Effient

Plateletpheresis

Deferral period-single donation

2 days, no more than twice in 7 days

Plateletpheresis

Deferral period- double or triple apheresis

7 days

Plateletpheresis

How many time can you donate in a year?

24 times

Total volume of plasma collected during any plateletapheresies procedure can't exceed

500 mL

600 if the donor weighs over 175 lbs

Plateletapheresis units are typically

Leukocyte reduced (less than 5X10^6)

Granulocyte

Criteria (5)

Fever

Neutropenia less than 500/uL

Bacteremia, septicemia that antibiotic isn't helping

Reversible marrow aplasia

Reasonable chance of survival

Granulocyte

Shelf-life

24 hours at RT no agitation

Granulocyte

Therapeutic dose (2)

1X10^10

1 unit a day for 4 days

Granulocyte

Corticosteroids function

Mobilize granulocytes present in the non circulating pool

Increase number of circulating granulocytes to yield a higher count

Granulocyte

What can be given to the donor? (3)

Corticosteroids

Growth stimulating factor

HES (sedimenting agent)

Granulocyte

Corticosteroids given

Prednisone

Granulocyte

Corticosteroid side effects (3)

Exacerbate: diabetes peptic ulcers hypertension

Granulocyte

Growth stimulating factor function

Will increase the yield of granulocytes

Granulocyte

Growth stimulating factor-side effects

Muscle and skeletal pain

Granulocyte

HES

Allows for better separation of the layers with a higher granulocyte yield and less contaminating RBCs

Granulocyte

Found in what layer during separation

Buffy layer

HES

Side effects (3)

Circulatory volume expansion

Headaches

Peripheral edema

HES

What removes it from the body

RES

Granulocyte

What must be done before transfusion

Cross match

Irradiate (has lymphocytes)

Rationale of Therapeutic Apheresis (TA) is based on (2)

1. Pathogenic substance exists in the blood that contributes to a disease

2. Substance more effectively removed by apheresis than by the body's own homeostatic mechanisms