Transfusions

Question 1

What are the ABO groups and how do they get placed on RBC surface?

Answer 1

they are carbohydrates

placed on outer-membrane facing proteins through glycosylation

Question 2

what does plasma normally contain?

Answer 2

antibodies

Question 3

what is the universal plasma donor?

Answer 3

AB blood since the plasma has no antibodies in it

Question 4

what is the universal plasma receptor?

Answer 4

O blood since antibodies will not interact with it

Question 5

What is a common example of blood protein group?

Answer 5

Rh

Question 6

3 functions of glycosylation

Answer 6

1) antigen recognition
2) protein modification
3) protein anchoring

Question 7

How long do ABO antibodies take to develop?

Answer 7

about 1-3 months

Question 8

IgM vs. IgG antibodies

Answer 8

IgM is produced by A or B patients

IgG is produced by O patients

Question 9

what is the most common blood type?

Answer 9

O

Question 10

What percentage of the population is positive for Rh?

Answer 10

85%

Question 11

What response is triggered in an Rh- patient that recieves Rh+ blood?

Answer 11

IgG antibody production

Question 12

How can a baby be Rh+ and a mother be Rh-?

Answer 12

if baby receives only one Rh copy from father, the baby will be Rh+

Rh- is haploinsufficent

Question 13

What do you do if a baby is Rh+ and mother is Rh-?

Answer 13

start RhoGAM

prevent mother from ever producing Rh+ antibodies

Question 14

How do Rh differences between mother/fetus cause hydrops fetalis?

Answer 14

if mother is Rh- she will produce antibodies against the Rh+ fetus

during her SUBSEQUENT pregnancies, an immune response will attack the fetus’s RBCs that are Rh+

this will lead to anemia in the baby and hydrops fetalis

Question 15

How do you blood type for ABO/Rh compatibility?

Answer 15

type and cross!

Question 16

forward typing and equivalent test

Answer 16

patient’s RBCs are tested against commercial antibody

RBCs will clot with different antibodies depending what antigen they express

direct coombs

Question 17

reverse typing and equivalent test

Answer 17

patient’s serum is tested again commercial RBC

serum contains antibodies that may clot with RBC

indirect coombs

Question 18

antibody screen

Answer 18

test patient serum against RBC with known protein expression (all other proteins besides the patient’s ABO type)

Question 19

final test to match patient with unit of blood

Answer 19

patient’s plasma is mixed with a sample of donor RBC

did the patient’s plasma attach the RBC?

Question 20

3 indications for RBC transfusion

Answer 20

acute blood loss >15% TBV

Hb <7

chronic transfusions (thalassemia, sickle cell)

Question 21

indication for platelet transfusion

Answer 21

quantitative OR qualitative platelet defects and bleeding

Plts < 10,000 with bleeding

Plts < 50,000 for major surgery

Question 22

indications for plasma transfusion

Answer 22

multiple coagulation factor deficiencies (liver failure, DIC)

rapid reversal of warfarin (vitamin K will take too long)

Dilutional coagulopathy from massive
transfusion

Question 23

indicates for cryoprecipitate transfusion

Answer 23

Dysfibrinogenemia or
hypofibrinogenemia

complex coagulation factor deficiency

deficiency of specific factors

Question 24

examples of coagulation factor deficiency

Answer 24

DIC, liver failure

Question 25

side effect of bacterial contamination of a blood unit

Answer 25

can lead to fatal sepsis?

Question 26

acute hemolytic transfusion reaction

Answer 26

occurs due to incorrect blood type transfusion

mismatched blood triggers IgG antibody response

preformed antibodies immediately bind

can trigger coagulation and complement

DIC and massive hemolysis

Question 27

DIC stands for

Answer 27

Disseminated intravascular coagulation

activation and dysregulation of both thrombosis and fibrinolysis

Question 28

delayed transfusion reaction

Answer 28

rapid hemoglobin decrease over 3-14 days after transfusion

prior exposure to an RBC protein antigen made antibodies in the past

now these antibodies will kick up in transfusion with a larger response

Question 29

examples of some RBC protein antigens

Answer 29

Kelly, Duffy, Rh

Question 30

TRALI

Answer 30

transfusion associated acute lung injury

Question 31

TACO

Answer 31

transfusion associated cardiac overload

Question 32

transfusion infections

Answer 32

can occur if blood contains a bloodborne pathogen such as HIV or HBV