Ch. 1 - Donor selection & testing Flashcards
What sorts of blood products can a donor provide? How much?
Whole blood (up to 1 unit)
Packed red cell units (up to 2 units via pheresis)
Platelets (1 full unit via pheresis)
Plasma (??? via pheresis)
Granulocytes (??? via pheresis)
What is autologous blood donation? Directed blood donation? How are these units handled differently?
Autologous blood donation is meant for the donor’s future use. As it will be either used for the donor and discarded, it does not require infectious testing.
Directed donations are meant for a specific other individual, and is still subject to full testing (and often irradiation).
What are the four major steps of donor selection?
- Donor screening by means of medical history review
- Reading of educational materials
- Brief physical examination
- Laboratory testing
What is the difference between the UDHQ and the aDHQ?
UDHQ: Uniform donor history questionnaire, this is standard for all patient donors and is meant to capture events including those in the distant past.
aDHQ: Abbreviated donor history questionnaire, this is for frequent donors and is meant to capture more recent events.
What is the minimum acceptable age for blood donation?
17 years old (or 16, with parental consent)
On the DHQ,
- What medications are inquired about?
- What history of travel is relevant?
- What high-risk behaviors are considered?
- Aspirin (within past 2 days)
- Travel to malaria-endemic countries, prolonged time in the UK or other European countries.
- Sexual contact (especially sex work and sexually transmitted diseases), piercings/tattoos, illicit drug use, imprisonment.
What educational points discussed with potential donors?
The rationale of the DHQ, the conditions under which a patient should not donate, the testing any donated blood may undergo, as well as risks/complications of donation (eg iron deficiency).
What weight and hemoglobin levels should be met for donation?
Is there a maximum hemoglobin level?
At least 110lbs (can still donate if above 88lbs, based on calculation of blood to be drawn below 15% of TBV).
At least 12.5g/dL for women, at least 13g/dL for men. For either sex, 13.3g/dL (Hct 40%) for pheresis donation, and 11.0 g/dL for autologous units.
Yes; 20g/dL for whole blood and 18g/dL for pheresis units.
What ranges of vitals should be observed for blood donation?
Temperature: Should not exceed 37.5C
Pulse: Between 50-100 with no arrhythmias. Lower is OK in athletes.
BP: 90-180 / 50-100
What infectious organisms are routinely tested for on donor blood?
HIV-1, HIV-2
HTLV-1, HTLV-2
Hep B, Hep C
West Nile virus, Zika virus
Treponema pallidum, Trypanosomal cruzi
Sometimes: Babesia, CMV
In general, how is infectious disease screening performed on donated blood?
Nucleic acid testing (NAT) for DNA or RNA done in “minipools”.
Immunoassays (ELISA/CLIA) for donor antibodies or infectious antigens, often paired with confirmatory testing.
What are the relative risks of acquiring the following infection from blood units?
HIV
HBV
HCV
HTLV
Bacterial sepsis
HIV: 1 in 1.5mil
HBV: 1 in 1 million
HCV: 1 in 1.2 million
HTLV: 1 in 2.7 million
Bacterial sepsis: 1 in 50,000-80,000
What behaviors are considered high risk for HIV?
If HIV testing is positive, how long is deferral?
IVDU, sex work, transplant/grafts, blood exposure, MSM, MSM contact, tattoos/piercing, other STIs, incarceration.
Testing positive for HIV results in permanent deferral from blood donation.
What testing outcomes can lead to permanent deferral for HBV or HCV?
A positive HBsAg or anti-HCV antibody with confirmation NAT testing
Testing positive for anti-HBc twice
What is the deferral for a patient with high risk exposure to HIV or HBV/HCV (for example, needle-stick or sexual contact with one affected)?
1 year
