Transfusion Biology And Therapy

Question 1

The production of antibodies directed against antigenic determinants of another individual

Answer 1

Alloimmunization

Question 2

First and most important blood group antigen system in transfusion medicine

Answer 2

ABO blood group system

Question 3

Universal recipient blood type, with regards to RBC transfusion

Answer 3

Type AB

Question 4

Universal donor blood type

Answer 4

Type O

Question 5

Presence of this antigen confers Rh “positivity”

Answer 5

D antigen

Question 6

Most common cause of incompatibility during pretransfusion screening

Answer 6

Antibodies to Lewis system

Question 7

Used for the collection of multiple units of platelets from a single donor

Answer 7

Apharesis

Question 8

How much hemoglobin and hematocrit increase to be expected in BT of 1 unit pRBC?

Answer 8

Increase by 10g/L hemoglobin and 3% hematocrit

Question 9

Ideal blood component for patients who have sustained acute hemorrhage of >/= 25% total blood volume loss

Answer 9

Whole blood

Question 10

An apharesis procedure done to patients with hemoglobinopathies by which sickled RBCs are replaced by donor RBCs

Answer 10

RBC Exchange

Question 11

In normovolemic patients without cardiac disease, what is the cutoff hemoglobin content that can maintain adequate oxygenation?

Answer 11

70 g/L

Question 12

Platelet count Threshold for prophylactic platelet transfusion, without invasive procedure

Answer 12

10,000 /uL

*50,000 /uL for invasive procedures

Question 13

Signs of increased platelet consumption

Answer 13

Splenomegaly
Fever
DIC

Question 14

Lowers risk of alloimmunization for those requiring multiple transfusions

Answer 14

Use leukocyte-reduced components

Question 15

Blood component containing stable coag factors and plasma proteins: fibrinogen, antithrombin, albumin, protein C & S; used in warfarin reversal and TTP treatment

Answer 15

Freah frozen plasma (FFP)

Question 16

Blood component with fibrinogen, factor VIII, vWF; ideal for supplying fibrinogen to volume-sensitive patient

Answer 16

Cryoprecipitate

Question 17

2 types of transfusion reactions

Answer 17

1) immune-mediated: due to preformed donor/recipient antibody
2) nonimmune: due to chemical property of blood component

Question 18

Test that detects the presence of antibodies (or complement) on the surface of erythrocytes

Answer 18

Direct Coombs (antiglobulin) test

Question 19

Test that detects antibodies in the serum that may bind to donor erthrocytes

Answer 19

Indirect Coombs (antiglobulin) test

Question 20

Most frequent reaction associated with transfusion of cellular blood components; characterized by chills and rigors and >1 deg Celsius rise in temp

Answer 20

Febrile nonhemolytic transfusion reaction

Question 21

Severe allergic reaction presenting after few mL of BT; may present with DOB, couging, nausea/vomiting, hypotension, bronchospasm, shock

Answer 21

Anaphylactic reaction

Question 22

Frequent complication of allogenic stem cell transplantation in which lymphocytes from the donor attack and cannot be eliminated by an immunodeficient host

Answer 22

Graft-versus-host disease

*Can be prevented by irradiation of cellular components before BT to patients at risk

Question 23

BT reaction presenting with hypoxia and bilateral interstitial infiltrates during or within 6 hr; results from transfusion of donor plasma with high titer anti-HLA class II antibodies that bind to recipient leukocytes

Answer 23

Transfusion-Related Acute Lung Injury (TRALI)

Question 24

Treatment for TRALI

Answer 24

Supportive; patients recover without sequelae

Question 25

The only pretransfusion selection test to prevent RBC alloimmunization

Answer 25

Cross-matching (for RBC antigen)

Question 26

How many units of RBC before Signs/symptoms of iron overload appear?

Answer 26

100 units RBC