CP36 - Blood transfusion

Question 1

what are the different component of blood?

Answer 1

RBC, platelets, plasma

Question 2

what is leucodepletion

Answer 2

removal of RBC during processing of the blood before transfusion

Question 3

what can be derived from the plasma

Answer 3

fresh frozen plasma, cryoprecipitate, fractionation (for production of albumin, immunoglobulin, factor conc.)

Question 4

what is cryoprecipitate

Answer 4

derived from blood and contain many coagulating factors

Question 5

what is transfusion threshold

Answer 5

lowest conc of Hb that is no associated with symptoms of anaemia - different with different groups of ppl

Question 6

what is the amount of Hb that should be transfused to patients who have mild symptoms of anaemia

Question 7

what is the amount of Hb that should be transfused to patients who have cardiovascular disease

Question 8

when is transfusion required when acute anaemia due to blood loss

Answer 8

blood loss more than 1.5L

Question 9

what is the transfusion threshold for chronic anaemia

Answer 9

80-100g/L

Question 10

what can happen to patients who are regular transfusion?

Answer 10

iron overload

Question 11

what is the transfusion threshold for chronic anaemia due to inherited anaemias

Answer 11

90-95 g/L

Question 12

what temp is platelets stored at?

Answer 12

22 degree C and for 5 days

Question 13

how is platelet collected?

Answer 13

not blood donation but apheresis (donate only platelet)

Question 14

what is platelet transfusion used for?

Answer 14

massive haemorrhage, bone marrow failure, prophylaxis for surgery

Question 15

what temp is fresh frozen plasma stored at?

Answer 15

-30 degree C up to 24 months

Question 16

when will you not transfuse fresh frozen plasma

Answer 16

patient on warfarin or warfarin overdose

Question 17

what is group and screen

Answer 17

determination of ABO and Rh(D) group,

screened for antibodies against other clinically significant blood group antigens

Question 18

what is crossmatching

Answer 18

Patients plasma is mixed with aliquots of donor red cells to see if a reaction (agglutination or haemolysis) occurs

Question 19

what are the 2 different types of transfusion reactions

Answer 19

acute transfusion reactions 24 hrs

Question 20

what are the general subclassifications for transfusion reactions

Answer 20

immunological & non-immunological

Question 21

what happens is acute transfusion reactions

Answer 21

immuno - Acute haemolytic transfusion reaction
ABO incompatibility
Allergic /anaphylactic reaction
TRALI (Transfusion-related acute lung injury)

non - Bacterial contamination
TACO (transfusion associated circulatory overload)
Febrile non-haemolytic transfusion reaction

Question 22

what happens is delayed transfusion reactions

Answer 22

immuno - Transfusion-associated graft-versus-host disease (TA-GvHD)
Post transfusion purpura

non-immuno - Transfusion Transmitted Infection (TTI) –viral/prion

Question 23

what is the pathogenesis of acute haemolytic reaction

Answer 23

ABO incompatibility and all the symptoms are caused by the release of free haemoglobin

Question 24

what are some examples consequences of acute haemolytic reaction.

Answer 24

deposition of Hb in the distal renal tubule results in acute renal failure.

stimulation of coagulation results in microvascular thrombosis

stimulation of cytokine storm

Scavenges NO resulting in generalized vasoconstriction

Question 25

what are some signs and symptoms for acute haemolytic reaction

Answer 25

fever and chills 
back pain 
infusion pain 
hypotension/shock 
haemoglobinuria 
increased bleeding 
chest pain 
sense of impending death

Question 26

what are some clinical features in delayed haemolytic reaction

Answer 26

fatigue, jaundice, fever

Question 27

what causes delayed haemogobulin reaction

Answer 27

immune IgG antibodies against RBC antigen other than ABO

Question 28

what is the cause of transfusion related acute lung injury

Answer 28

Donor has antibodies to recipient’s leukocytes

activated WBC lodge in pulmonary capillaries

release substances that cause endothelial damage and capillary leak

Question 29

what are some symptoms for transfusion-associated circulatory overload?

Answer 29

sudden dyspnea
orthopnoea
tachycardia 
hypertension 
hypoxemia

Question 30

what causes Febrile non-haemolytic transfusion reactions

Answer 30

are due to cytokines or other biologically active molecules that accumulate during storage of blood components