Components - Platelets/ HLA Flashcards
Recall travel and storage requirements for platelet and granulocyte components
Perform visual inspection of Platelet an Granulocyte Components and labels. Recognize a platelet swirl.
Identify the clinical indication of platelet transfusion. Determine appropriate dosage of aphereseis platelet products and whole blood derived products.
Identify the patient population receiving granulocyte transfusions
Compare Pre-Transfusion testing for red cell components vs platelet components
Recognize the testing techniques performed for HLA type & Platelet Cross match testing
Solve an HLA paternity problem utilizing antigen cross expression logic
What is the normal value of platelets?
150,000 - 350,000 / uL
What may happen when you have a platelet value of <10,000/ uL?
spontaneous hemorrhage may occur
True or False: >50,000/uL minimizes hemorrhage during surgery?
True
What is Platelet’s function in Hemostasis?
- Platelet plug
- Stabilize plug by fibrin formation
- Maintenance of vascular integrity
When are platelets transfused? State 3 reasons
- To increase platelet count
- Prophylactically for Oncology patients
- If a patient’s platelets are not functioning (PFA test)
On Oncology patients, we know that the chemo is going to kill the blood plts.
Chemo therapy is hard on platelets
What is Refractory?
failure to achieve an acceptable platelet count following platelet transfusion.
True or False: 1 apheresis or 6 whole blood concentrates about +30,000 - 50,000 / uL of platelets
True
Plate activation occurs ______ storage
during
–
- ATP released
- Platelets aggregate
- Increase glucose consumption lead to Lactic acid
- Decrease in pH will cause platelets to swell (bad platelets)
Platelet storage lesion means the _____ of quality during storage
loss
What are the storage conditions for platelets?
- Temperature: 20-24 C
- Continuous agitation (rocker)
- Cold storage results in irreversible spherical shape change
- Facilitates oxygen transfer in the boat needed to maintain pH
When do platelets expire?
- Expires 5 days post collection
– Increased chance for bacterial contamination at storage, length of time pH can be maintained in the bag
What are the alternative storage options for platelets?
- Platelet Additive Solution (PAS)
- 7-platelets
- Frozen platelets
- Cold storage is still being studied
How does Platelet Additive Solution (PAS) storage work?
- reduces plasma stored with platelets up to 60% (less transfusion reaction)
How does 7 day platelets storage work?
Platelets must be tested for bacterial contamination on day of transfusion
How does Frozen platelet storage work?
platelets can be stored frozen and kept up to 2 years with DMSO.
33% of platelets are viable from this process
What is pathogen inactivation?
Pathogen inactivation impair pathogen’s ability to replicate by damaging DNA by using either ultraviolet light or Alkylating agents.
This some how inactivates bacteria DNA
What would Pathogen Inactivation be use for?
- Effective for viruses, bacteria, fungi, protozoa, and leukocytes (ineffective for prions)
What is blood products is pathogen inactivation being used on?
- Currently in use for platelets and plasma
What is the donor qualification criteria for donating platelets?
- Must meet RBC donor qualifications
- Platelet counts need to be greater than 150,000.
- Pt is not taking the following medications (Aspirin - 2 days, Plavix - 14 days )
- Interval between random donor - 8 weeks
- Interval between apheresis donors > 2 days
- Double/ Triple bags > 7 days
- No more than 24 donations in a year.
- No more than 500 mL of fluids can be removed
List the steps of component preparation specific to platelet components from whole blood donations
- Whole bloods collected
- Centrifuge
- Rest 1-2 hours to unclip then place onto an agitator for storage up to 5 days
- Sterile Docking pools of 4-6 different donors
- Therapeutic does 5000-10,000 platelets/uL per single donation. Pools expected dose 20,000-60,000.
List the steps of component preparation specific to platelet components from apheresis collection
- Larger gauge/smaller bore size of needle than with random donor
- 45-120 minutes. The patient is attached for the duration of the procedure and infused with saline and anticoagulants
- Optical sensors divert the specific component to a collection bag. Multiple components can be collected at the same time
- Variables: Centifugation speed and diameter, Dwell time of blood in the centrifuge , Types of solutions added, Cellular and Plasma content of donor or patient
- Different ddeferalls - blood loss must be closely monitored, cannot excessed more than 500 mL or RBC deferral applies (8 weeks)
