Blood collection and processing Flashcards
Why are donors in Australia voluntary and unpaid?
- bc more likely get altruistic (selfless) donors - continue to donate
- if it was paid it would attract ppl w/high-risk blood born pathogens
What are the two types of donation and what can be produced from each?
- Whole blood: separated into RBC, plasma & plts
2. Apheresis: plasma/plts collected (using aprehesis machine)
Describe the processing of whole blood for transfusion component production.
- blood is centrifuged = plasma, buffy coat (WBC, plt), RBC layer
- placed in a Macropress blood separator = separates plasma & RBC in different bags & buffy coat in original bag
- RBC bag: leukoreduced (removed WBC) & add SAGM (additive solution for storage)
- Buffy coat poled w/ 4 donors w/ same ABO Rh(D) group. Washed w/ plt additive solution (PAS) -> washing collected in a bag -> macropress => separate plt & RBC
What are the comonents in SAGM & function of each?
- Saline: maintain tonicity of solution
- Adenine & Glucose: storage & prodive ADP = maintain viabiltiy (still works)
- Mannitol: prevent haemolysis
What is the benefit of apheresis donation for component production?
cellular components are already separated = no further processing
In which circumstances are transfusions appropriate?
- blood loss
- Anaemic:
• [Hb] < 70g/L in healthy person
• [Hb] 70 - 100 g/L in certain populations
• ACTIVELY BLEEDING & have [Hb] > 100 g/L - replacement of cells e.g. WBC
- replace specific plasma factors
In which circumstances are transfusions inappropriate?
- undiagnosed / asymptomatic anaemia
- post-operative haemoglobin > 80 g/L
- Reversible short - term anaemia (ie. can take medication instead)
- Anaemia responsive to therapy
- Improve general “well-being”
How much should 1 unit of RBCs increase an adult [Hb] by? & significance if not reached
a) ~ 10 g/L
b) <10 g/L may indicate transfusion reaction
How much should 1 unit of platelets increase an adult [plt] by? & significance is not reached
a) 20-50 x 10^9/L
b) <20 x 10^9/L may mean plt are being destroyed
What is the shelf life of RBCs? Platelets? Why is the platelet shelf life shorter?
a) RBC stored @ 2-6ºC for max. 42 days
b) Plt stored @ 20-24ºC for 5 days (w/ gentle agitation)
c) bc stored @ room temp. = inc. risk of bacterial contamination
What are the indications for Fresh Frozen Plasma (FFP)?
- Coagulopathies (where Tx is not available)
- Bleeding patients - require factor replacement
- Warfarin overdose (OD) (prothrombin complex concentrate preferred > warfarin reversal)
What are the indications for Cryoprecipitate administration?
- Dec. plasma [fibrinogen]
- Dysfibrogenaemia
- Disseminated intravascular coagulation (DIC)
Role of Australian Red Cross Lifeblood (ARCLB)
- blood collection
- blood testing
- Component preparation
- Delivery to external parties: CSL & health providers
- Management of blood inventory
how a safe blood is maintatined
- voluntary, unpaid donors
- meet donation criteria: age, height, weight, [Hb]
- Donor Questionaire: health, lifestyle, travel Hx, Medical Hx, declaration
- Screening test for presence of transfusion transmittable pathogens
WHat lab tests are done on donated blood?
- ABO/Rh(D) grouping, Ab screen
- Routine viral screening: Look @ presence of Ag or Ab e.g. HIV Ab, Hepatitis B Ag & C Ab
- Selective screening for malaria & Cytomegalovirus (CMV)
- Not all pathogens are screen e.g. dengue so have questionnaire
