Transfusions* Flashcards
blood components
red cells
platelets
fresh frozen plasma
cryoprecipitate
blood products
human albumin IV immunoglobulin human normal immunoglobulin specific immunoglobulins (tetanus, Hep B, varicella, rabies) Anti D immunoglobulin prothrombin complex concentrates
blood donors have to be what
volunteers healthy able to spare 465ml of blood min weight 50k Hb 13.5 g/dl males and 12.5 for females
safety of raw material
exclude infective risk
exclude risk of transmitting disease - malign, neurological disease
donor is encourages to contact if become unwell within 2 weeks of donating
what is the donor blood tested for
HIV 1 and 2 AB and PCR HCV AB and PCR HBV AG and PCR syphilis AB HTLC1 and 2 AB HEV PCR
processing the blood
bleed the donor
centrifuge the bag of blood and anticoagulant
express components - plasma at in the top bag and red cells into the bottom
the red cells fun through a filter - leucodepleted red cells in optimal additive solution
temp storage of red cells
shelf life of red cells
removal timing
4 degrees +/-2
shelf life 35 days
if removed from controlled storage for more than 30 mins must be transfused or discarded
must be transfused within 4 hours of leaving controlled storage
platelets stored at
shelf life
transfuse timing
22 degrees with continual agitation
shelf life 7 days if bacterial monitoring is applied
transfuse within 1 hour
fresh frozen plasma stored at
shelf life
transfusion timing
stored at -30 degrees for up to 3 years
thawed prior to transfusion 40 min to thaw and transfuse within 4 hours
antigens and group A
B
AB
O
carry the A antigen
B antigen
A and B antigen
dont carry a A or B antigen
population frequency of A
B
AB
O
A 42%
B 8%
AB 3%
O 47%
inheritance of ABO groups which chromosome
O gene
A and B
9
O gene is silent
A and B dom over O
A and B co dominant
Rh (D) inheritance
D and d
d is silent
pop freq of
DD
Dd
dd
pos 35%
pos 48%
neg 17%
screen patients plasma for irregular red cell antibodies
commonest
not naturally occurring
develop after previous exposure to red cells - prev transfusion, prev preg
Anti D, Anti K, Anti c, Anti E, Anti Fy^a
whats used to detect and identify irregular antibodies
group O red cells with Anti IgG AB
Indirect antiglobulin test /indirect coombs test
transfusing red cells timing
each unit of red cells should be completely transfused within 4 hours of leaving the blood fridge
if red cells have been out of the fridge for more than 30 mins they can’t be returned
indications for red cell transfusion
anaemia - low Hb
acute blood loss
acute blood loss approach
arrest bleeding
gain IV access
sampled for cross matching and other tests
restore and maintain good blood volume - N saline, albumin, gelofusion
Emergency group O, Rh(d) neg blood
then specific blood
platelet transfusion adult dose equivalent
stored at
for how long
4 donors or 1 using a cell separator machine
22 degrees for 5 days contact gentle agitation
platelet production from whole white blood donations
centrifuge transfer pack
plasma through the top and red cells through the bottom and white cells and platelets in original bag
the original bag plus 3 others centrifuged to remove white cells
indications for platelet transfusion
low platelet count and at risk of bleeding
indications for fresh frozen plasma
bleeding or surgery in liver disease with impaired coagulation
coagulopathy following massive transfusion
DIC
immediate haemolytic transfusion reaction
e.g. if group A blood given to someone with group A
IgM anti A binds to the cells - activates complement cascade
- acute immediate haemolytic transfusion reaction - complement cascade
release of CSa and C5a - powerful anaphylotoxins, increase vascular permeability, dilute blood vessels, cause release of serotonin and histamine
formation of MAC - rupture of transfused cells
coagulation - DIC
acute immediate haemolytic transfusion reaction - kinin system
activated factor XII activates kinin system
formation of bradykinin - arteriolar dilatation, increased vascular permeability
hypotension - vasoconstruiction in kidneys and other organs
immediate haemolytic transfusion reaction features
may being after only 1ml is transfused pyrexia/rigors faintness/dizziness tachycardia/tachypnoae /hypotension pallor/sweating headaches/chest [ain local pain at infusion site cyanosis
actions for acute immediate haemolytic transfusion reaction
stop transfusion
start IV fluids
obtain blood samples for transfusion lab
send remains of unit to lab
- delayed haemolytic transfusion reactions
haemolysis 5-10 days after transfusion
similar to acute but not acute
unexplained fall in Hb as transfused red cells are destroyed
lab features of delayed haemolytic transfusion reactions
anaemia, spherocytic red cells on blood film
elevated bili and LDH
pos DAGT and/or appearance of red cells allo-AB
degree of renal failure
- febrile non haemolytic transfusion reaction
ix
prevention
2% red cell
20% platelet transfusions
rapid rise of temp 1-2 degrees, chills and riggers
AB to contaminating white cells
release of cytokines and vasoactive substances form white cells during storage
HLA AB
anti-paretics
leucodepleted blood components
- urticarial reactions what
presentation
treatment
mast cell IgE response to infused plasma proteins
rash/weals within mins of transfusion
slow the transfusion
consider init histamines
- circulatory overload
pulmonary oedema
elderly and those w CCF
reduce risk w diuretics furosmide
- bacterial infection
fever, collapse, shock, DIC
red cells - pseudomonas, yersinia
platelets: staph, strep, erratic, salmonellae
- viral infection
HIV 1/6mill
HBC 1/1.6 mill
HCV 1/26 mill
