Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pathology by week > W16 - Blood transfusion 2 > Flashcards

W16 - Blood transfusion 2 Flashcards

1
Q

Adverse reactions to transfusion = time cut off for acute vs delayed

A

24 hours
<24 hours = acute
>24 hours = delayed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Name 5 types of ACUTE adverse reactions to transfusion

A
  1. Acute haemolytic (ABO incompatible)
  2. Allergic/anaphylaxis
  3. Infection (bacterial)
  4. Febrile no-haemolytic
  5. Respiratory
    => Transfusion associated circulatory overload (TACO)
    => Acute lung injury (TRALI)
    => Transfusion associated dyspnoea (TAD)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name 5 types of DELAYED adverse reactions to transfusion

A
  1. Delayed haemolytic transfusion reaction (antibodies)
  2. Infection (viral, malaria, vCJD)
  3. TA GvHD
  4. Post transfusion purpura
  5. Iron overload
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What 4 things should you measure as baseline when giving transfusion? How frequently should you measure?

A

1- Temp
2- HR
3- RR
4- BP
repeat after 15 minutes -> repeat hourly and at the end of transfusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Febrile non-haemolytic transfusion reaction (FNHTR)

  • when does it occur?
  • what are the symptoms?
  • treatment?
A

Febrile non-haemolytic transfusion reaction (FNHTR)
- when does it occur = during/soon after transfusion (blood or platelets)

  • what are the symptoms = rise in temp of 1 degrees C, rigors
  • treatment = stop/slow transfusion + paracetamol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cause of febrile non-haemolytic transfusion reaction (FNHTR)

A

due to donor white cells remaining in product during storage and releasing cytokines => now RARE due to leucodepletion of donor product

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Allergic transfusion reaction:

  • when does it occur?
  • what are the symptoms?
  • treatment?
A

Allergic transfusion reaction:
- when does it occur = during/after transfusion (esp plasma)

  • what are the symptoms = mild urticarial rash with wheeze
  • treatment = stop/slow transfusions + IV antihistamines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Cause of allergic transfusion reactions

A

due to a plasma protein in donor, so it may NOT occur again depending on how common the allergen is
- commoner in recipients with other allergies and atopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Acute haemolytic reaction (aka wrong blood):

  • when does it occur?
  • what are the symptoms?
  • treatment?
A

Acute haemolytic transfusion reaction (aka wrong blood):
- when does it occur = within 24 hours

  • what are the symptoms = signs of intravascular haemolysis:
  • restless
  • chest/loin pain
  • fever
  • vomiting
  • flushing
  • collapse/shock (BP low, HR high)
  • treatment = stop transfusion, check patient/component, take FBC, LFTs, clotting, repeat x-match and direct antiglobulin test (DAT), discuss w/ haematology
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

In terms of transfusion reactions, what is the #1 reason why they occur?

A

clerical error!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Bacterial contamination transfusion reaction:

  • when does it occur?
  • what are the symptoms?
  • treatment?
A

Bacterial contamination transfusion reaction:

  • when does it occur = within 24 hours
  • what are the symptoms =
  • restless
  • chest/loin pain
  • fever
  • vomiting
  • flushing
  • collapse/shock (BP low, HR high) due to endotoxin release
  • treatment = stop + abx + supportive
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Which transfusion product is more likely to grow bacteria - red cells or platelets?

A

Platelets because they are stored at room temp whereas red cells are stored at 4 degrees C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Anaphylactic transfusion reaction:

  • when does it occur?
  • what are the symptoms?
  • treatment?
A

Anaphylactic transfusion reaction:
- when does it occur = soon after start of transfusion

  • what are the symptoms:
  • shock (low BP, high HR)
  • SOB +/- wheeze
  • laryngeal +/- facial oedema
  • treatment =
    1) stop blood transfusion
    2) adrenaline
    3) supportive care
    4) inhaled bronchodilator + glucagon + antihistamine + corticosteroids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Cause of anaphylactic transfusion reactions

in what disease are anaphylactic transfusion reactions more SEVERE?

A

IgE abs in patient => mast cell degranulation + vasoactive substance
*more severe in IgA deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the most common pulmonary complication of transfusion reaction?

A

TACO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

TACO:

  • when does it occur?
  • why does it occur?
  • what are the symptoms?
  • CXR findings?
A

TACO:
- when does it occur = ACUTE (within 6 hrs usually)

  • why does it occur = due to lack of attention to fluid balance, esp. in CF, renal impairment, hypoalbuminaemia, + fluid balance
  • what are the symptoms:
    1) SOB
    2) reduced O2 sat
    3) high HR
    4) high BP
  • CXR findings:
    1) fluid overload
    2) Cardiac Failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

TRALI:

  • when does it occur?
  • what are the symptoms?
  • CXR findings?
A

TRALI:
- when does it occur = ACUTE (during or within 6 hrs usually)

  • what are the symptoms:
    1) SOB
    2) reduced O2 sat
    3) high HR
    4) high BP
    **same as TACO)
  • CXR findings:
    1) bilateral pulmonary infiltrates not due to circulatory overload
18
Q

pathophysiology of TRALI

A

why does it occur = anti-WBC abs in donor => interact with patient WBCs => aggregates => stuck in pulmonary capillaries => lung damage

**sometimes abs not implicated

19
Q

Which infections cause (delayed) associated with transfusion reaction

A
  1. Malaria
  2. HIV 1/2, HEV, HBV, HCV, HLV 1/2, Parvovirus, CMV, WNV, Zika
  3. Variant CJD
20
Q

Pathophysiology of delayed haemolytic transfusion reaction

A

1-3% of all patients transfused develop an “immune” antibody to an RBC antigen they lack = ALLOMMUNISATION

if patient receives another transfusion with RBCS expressing the same antigens => abs cause RBC destruction = EXTRAVASCULAR HAEMOLYSIS (as IgG) so takes 5-10 days

21
Q

What investigation findings will suggest delayed haemolytic transfusion reaction?

A

haemolysis screen:

  • raised:
    1) bilirubin
    2) LDH
    3) retics
  • reduced:
    1) Hb
  • DAT +
  • Haemoglobinuria (over few days)
  • U&Es - if renal failure
  • repeat G&S - for new abs
22
Q

Transfusion associated Graft-V-Host Disease (TaGVHD):

  • when does it occur?
  • what are the symptoms?
  • prognosis?
A

Transfusion associated Graft-V-Host Disease (TaGVHD):

  • when does it occur = usually 7-10 days post transfusion
  • what are the symptoms:
    1) severe diarrhoea
    2) liver failure
    3) skin desquamation
    4) BM failure
  • prognosis?
    rare, but always fatal (death weeks to months post transfusion)
23
Q

Pathophysiology of Transfusion associated Graft-V-Host Disease (TaGVHD)

A

Normally => donor’s blood contains lymphocytes => patient immune system recognises donor’s lymphocytes as foreign and destroys them

TaGVHD => susceptible patient (very immunosuppressed) = lymphocytes not destroyed => lymphocytes recognise patient tissue HLA ags as foreign => attack patient’s gut, liver, skin, BM

24
Q

How to prevent TaGVHD?

A

Irradiate blood components for very immunosuppressed or give HLA-matched components

25
Q

Post transfusion purpura:

  • when does it occur?
  • what are the symptoms?
  • prognosis?
A

Post transfusion purpura:
- when does it occur = 7-10 days post transfusion (blood or platelets)

  • what are the symptoms = purpura = pin prick red/purple blood spots
  • prognosis = resolves in 1-4 weeks but may cause life threatening bleeding
26
Q

Post transfusion purpura: who does it affect? Treatment?

A

HPA-1 negative patients who were previously immunised by pregnancy or transfusion and have anti-HPA-1a antibody
- treatment = IVIG

27
Q

What is iron overload in transfusion? Treatment?

A

If lots of transfusions (>50), over time iron can accumulate = cause organ damage (liver, heart, endocrine)

  • Treatment = iron chelation with transfusion once ferritin >1000 (normally used in Thalassaemia/SCD)
28
Q

How does RhD- mom make anti-D during 1st pregnancy?

A

If child is RhD + => during delivery, mom exposed to foetal RhD+ red cells => make anti-D (6 months later)

29
Q

What happens to RhD- mom with anti-D in her 2nd pregnancy?

A

If foetus RhD + => maternal anti-D IgG crosses placenta => coats foetal RhD + cells => destroys them in foetal spleen and liver

30
Q

Clinical features (4) of baby with haemolytic disease of the newborn (HDFN)

A
  1. Anaemia signs (pale skin)
  2. Hyperbilirubinaemia signs (jaundice)
  3. Hepatosplenomegaly
  4. If hydrops fetalis => severe oedema in organs
31
Q

How and when are pregnant women assessed for red cell antibody?

A

Pregnant woman have G&S at around 12 weeks and again at 28 weeks to check for RBC abs

32
Q

What (5) is done if a G&S screen for pregnant woman comes back possible for RBC antibodies (anti-D)?

A
  1. Check if father has the antigen (and potentially baby has inherited it)
  2. Monitor level fo abs (high/rising)
  3. Check ffDNA sample
  4. Monitor foetus for anaemia (MCA doppler US)
  5. Deliver baby early as HDN gets worse in last few weeks
33
Q

If foetus is very affected by anti-D, what sort of things (4) can be done?

A
  1. intra-uterine transfusion to foetus
  2. Deliver a few weeks early
  3. At deliver - monitor baby’s Hb + bilirubin for several days
  4. Exchange transfusion to baby to lower bilirubin and increase Hb +/- phototherapy
34
Q

What is the most important antibody for cause HDFN?

A

Anti-D

35
Q

Can we prevent abs production by Rh - mom in her first pregnancy? If so, how?

A

YES
RhD - females of childbearing age given IV anti-D or IM anti-D.
NB: IM given closer to delivery when risk of fetomaternal blood loss

36
Q

MOA of prophylactic anti-D Ig?

A

RhD + foetal red cells get coated with anti-D Ig => are removed by mom’s spleen before they can sensitise the mom to produce anti-D abs

37
Q

When do you have to give prophylactic anti-D Ig for it to be effective?

A

within 72 hours of the sensitising event (maternofoetal blood exchange) = does NOT work if mom previously sensitized and has anti-D

38
Q

What are sensitising events in pregnancy?

A

Any time where maternal and foetal blood may exchange

  1. Delivery
  2. Spontaneous miscarriages
  3. Amniocentesis or CVS
  4. Abdominal trauma (falls/car accidents)
  5. External cephalic version
  6. Stillbirth or intrauterine death
39
Q

What is the routine antenatal anti-D prophylaxis (RAADP)?

A

1% of pregnancies with no sensitising events lead to RhD - mom becoming sensitized THEREFORE
all RhD - mom will receive routine anti-D prophylaxis in 3rd trimester (28w)

40
Q

Other than anti-RhD antibodies, name other antibodies (3) that may develop and cause foetal distress?

A

1) anti-c
2) anti-kell
(these 2 may cause severe HDN although rarer)
3) IgG anti-A and anti-B abs in Group O moms
(this causes mild HDN)

41
Q

Name 1 non-invasive foetal genotyping test
How is it used?

A

Cell-free foetal DNA (ffDNA)
=> can check for foetal D, C, c, E, K status at 11 + 2 weeks gestation

Pathology by week (70 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions