Blood Transfusion Flashcards
(91 cards)
1
Q
why transfuse blood?
A
mainly because of bleeding
failure of production
2
Q
how do blood groups arise?
A
antigens
red cell antigens are expressed on cell surface
3
Q
what is an antigen?
A
something that provokes an immune response
4
Q
what can red cell antigens be made from?
A
proteins
sugars
lipids
5
Q
the ABO gene codes for?
A
glycosyltransferase
6
Q
with a graph describe the antibody response to antigens
A
see notes
7
Q
what are glycans?
A
added to proteins or lipids on red cells
8
Q
what do A and B genes code for?
A
transferase enzyme
9
Q
what is A antigen?
A
N-acetyl-galactosamine
10
Q
what is B antigen?
A
galactose
11
Q
what is O gene?
A
non functional allele
12
Q
what antigens does everyone have?
A
2 x D-galactose
N-acetylgalactosamine
N-acetylglucosamine
13
Q
what inheritance is A and B and O?
A
A and B codominant
O is recessive
14
Q
group A antibodies
A
B
15
Q
group B antibodies
A
A
16
Q
group O antibodies
A
A and B
17
Q
group AB antibodies
A
No antibodies
18
Q
what type of immunoglobulin for anti-A/B is naturally occuring?
A
IgM
19
Q
IgG vs IgM
A
IgG needs protein
IgM ability to fix complement
20
Q
table red cells donor recipient compatibility
A
see notes
21
Q
table showing FFP donor/recipient compatibility
A
see notes
22
Q
why is FFP the reverse of RBC?
A
plasma contains antibodies not antigens
23
Q
when do rhesus negative individuals make anti-D
A
when exposed to RhD+ cells
24
Q
what kind of protein is RhD?
A
transmemebrane
25
why is RhD immunogenic?
hydrophobic
26
what can anti-D cause?
transfusion
| haemolytic disease of the newborn
27
what does DD mean?
RhD +ve
28
what does Dd mean?
RhD +ve
29
what does dd mean?
RhD -ve
30
what are blood donors screened for?
```
ABO, Rh
hep B/C/E
HIV
syphilis
(HTLV1, malaria, West Nile virus, Zika virus)
```
31
what kind of antibody is RhD?
IgG
32
what are the indications for red cell transfusion?
1. to correct severe acute anaemia, which might otherwise cause organ damage
2. to improve QoL in patient with otherwise uncorrectable anaemia
3. to prepare a patient for surgery or speed up recovery
4. to reverse damage caused by patient's own red cells - Sickle cell disease
33
other than freezing plasma what can you do?
extract clotting factors and albumin
34
what temp should RBCs be stored at?
4 C
35
how long should you transfuse RBCs over?
2-4hrs
36
RBC 1 unit increments is?
5g/l
37
what does 1 dose of platelets =?
4 pooled
| 1 apheresis donor
38
platelets 1 dose increments?
20-40 10^9l
39
what temp should platelets should be stored at?
22 c
40
self life of platelets?
7 days
41
how long to transfuse platelets over?
20-30 mins
42
indications for platelets?
massive haemorrhage
bone marrow failure
prophylaxis for surgery
cardiopulmonary bypass
43
what is the first clotting factor to run out?
fibrinogen
44
in massive haemorrhage what do you want to keep platelet count above?
75 x 10^9/;
45
what is bone marrow failure in terms of platelets?
platelet count < 10-15 x 10^9/l
| or <20 x 10^9/l if additional risk
46
platelets in prophylaxis for surgery
minor procedures 50x10^9/l
major 80x10^9/l
CNS or eye surgery 100x10^9/l
47
when would you use platelets in cardiopulmonary bypass?
only if bleeding
48
FFP is stored at what temp?
frozen
49
how long do you thaw FFP for?
30 mins
50
indications for FFP
massive haemorrhage
DIC with bleeding
prophylactic
51
indications for cryoprecipitate
fibrinogen low
52
how long to thaw cryroprecipitate for?
20 mins
53
if fibrinogen < 1.0g/dl how much cryoprecipitate?
1-2 pools
54
practical blood banking principles
```
Blood sent to Blood Bank
‘Second sample’ now implemented
Group and Screen/Save
Cross match
Tariff defined by ’MSBOS’
Samples kept for 7 days
But only valid for 2 days if recent transfusion
```
55
what type of near miss in blood banking is common?
```
patient not identified
sample not labelled at bedside
sample not labelled by person taking blood
prelabelled bottle
same surname
```
56
what is a group and save?
ABO and RhD type
checked against historical records
screen for allo-antibodies in serum
57
direct Coombs test
antibody already there
autoimmune haemolytic anaemia
passive antiD
haemolytic transfusion reactions
58
indirect Coombs test
Cross matching
59
describe Coombs test
anti-human immunoglobulin if get clumping
60
apart from ABO and Rh name some of the other most common
```
Kell
Duffy
MN
P
Lewis
Lutheran
```
61
how many people have allo-antibodies in blood?
1-10%
62
what blood is available in minutes?
O -ve
63
what is urgent blood?
```
10-15 mins
type specific (ABO/RhD)
```
64
what is non-urgent blood?
1 hr
full cross match
select correct ABO/RhD
if allo-antibodies choose antigen -ve blood
65
when may you need rapid control of bleeding?
obstetric intervention
surgery
interventional radiology
66
what does the massive haemorrhage protocol involve?
dedicated porter
6 units red cells
4 units FFP
1 unit platelets
67
never events in blood transfusion
death
| harm due to ABO incompatability
68
other risks of blood transfuson
```
TACO
TRALI
ATR
Febrile
allergic
vCJD risk
```
69
what is a prion disease?
transmittable by blood transfusion from early disease in sheep
70
steps taken to reduce risk of prion transmission in blood
leucodepletion
UK plasma not used for fractionation
imported FFP for all patients after 1996
71
management of blood reactions
stop transfusion
check patient identify against component label
consider: anaphylaxis, TACO, AHTR, bacterial infection, lung injury
72
acute transfusion reactions: pyrexia possible cause
FNHTR
73
acute transfusion reactions: pyrexia treatment
anti-pyretic
| other symptoms usually more concern - shock/DIC
74
acute transfusion reactions: urticaria possible causes
mild allergic reaction
| anaphylaxis
75
acute transfusion reactions: urticaria reatment
antihistamine
| other symptoms usually more concern - bronchospasm/shock
76
acute transfusion reactions: dyspnoea causes
TACO
TRALI
anaphylaxis
77
acute transfusion reactions: dyspnoea treatment
O2
diuretic
ventilation
adrenaline
78
acute transfusion reactions: shock causes
IBCT
anaphylaxis
TRALI
TAS
79
acute transfusion reactions: shock treatment
```
adrenaline (IV) hydrocortisone/antihistamine
IV fluid/ITU admission
ventilation
antibiotics
FFP/platelets if DIC
```
80
what is haemolytic disease of the newborn?
development of maternal anti-D antibodies (Sensitisation)
| IgG crosses placenta
81
most common antigens involved in haemolytic disease of the newborn
RhD - most immunogenic
also c, K
other Rh antigens, Jka, ABO less immunogenic
Positive DAT at birth, anaemia, jaundice
82
how to prevent haemolytic disease of the newborn
prophylactic anti-D
sensitising events
routine 28/40
83
treatment of haemolytic disease of the newborn
careful monitoring
antibody titres
doppler ultrasound
intrauterine transfusions
84
what is leucapheresis?
bone marrow harvests
| donor lymphocyte infusions
85
other banks that are not blood
```
bone
milk
tendons
heart valves
faecal
islet cells
mesenchymal stem cells
```
86
name 3 cellular therapies
leucapheresis
other banks
gene therapies
87
what does TRALI stand for?
transfusion related acute lung injury
88
what is TRALI?
Tranfused anti-leucocyte Abs in donor plasma interact with patient’s WBC
Bilateral pulmonary infiltrate
Supportive management, ventilation
89
what does PTP stand for?
post transfusion purpura
90
what is PTP?
Tranfused anti-leucocyte Abs in donor plasma interact with patient’s WBC
Bilateral pulmonary infiltrate
Supportive management, ventilation
91
what is transfusion associated graft versus host disease?
```
Rare, but always fatal
Graft of lymphocytes in donor’s blood
transfused to an immunocompromised host
Homozygosity of donor’s HLA type
Can be prevented by irradiation of blood
```
