Week 2- Blood transfusion Flashcards
slides 1-18
who decides who can or can’t give blood
the department of health based on independent advise from the advisory committee on the safety of Blood, Tissue and Organs (SaBTO)
which groups have a higher risk
why can you no longer be a blood donor if you have/ think you have had a blood transfusion anytime since jan 1st 1980
to reduce the risk of prion transmission in blood that can cause vCJD
what is vCJD
a fatal neurological disease caused by the same prion as BSE (bovine spongiform encephalopathy) (mad cow disease)
is there practical screening for blood donors
no
why is it unlikely that other countries will accept UK donations
because of the risk of vCID
(4 cases of TTI vCjD before 1999 from 3 donors)
which donors are deferred
- Tattoo, piercings, semi-permanent make up: 4 months
- Acupuncture (not through NHS): 4 months
- Travel: 4 weeks- 6 months
- pregnancy
- illness
what is required from a donor in order to tolerate the donation process
adequate haemoglobin levels
how is haemoglobin levels tested
copper sulphate test
how is the copper sulphate test carried out
a drop of blood from finger prick is dripped into a copper sulphate solution. the drop should fall between the liquid within 15 secs. (2 different strengths for males/ females)
what should the minimum haemoglobin levels for haemoglobin be
Hb of 125g/l for females
Hb of 135g/l for males
what is the safest type of blood supply
- volunteer donors
- unpaid
- donors who have no reason to lie about their health
23-27
when was the restriction on using plasma from UK donors introduced and why
in 1998 as a precautionary measure against vCjD
when was the restriction of using Uk plasma donations uplifted?
Feb 2021 by the department of health and social care
where are plasma donations taken
at repurposed former convalescent plasma donor centres (originally created for coronavirus research)
how many people needed immunoglobim therapy in the UK
around 17,000 (requiring more than 5.5m doses of blood plasma)
what are the principles of detection of blood borne diseases
- nucleic acid test (NAT) detects the DNA or RNA of a virus whilst it is replicating and has the shortest window period
- antigen assay becomes positive later in the infection
- antibody assay becomes positive after there is an immune response and has a much longer window period
35
how is HIV tested before donation
- Antibodies to the virus- anti-HIV 1 and 2
- HIV NAT
why is it important to test for HIV before a donation
HIV virus is responsible for AIDS, if left untreated, where CD4+ T cells are destroyed
this acquired immunodeficiency can lead to opportunistic infections and the development of rare cancers
how is hepatitis B tested before donation
- Hep B surface antigen (HBsAG) detection
- HBV NAT
- antibodies to the virus (if NAT screen positive)
How is hepatitis C tested before donation?
Antibody test
HCV NAT
