EXAM #2: TRANSFUSION REACTIONS

Question 1

What are acute hemolytic transfusion reactions?

Answer 1

INTRAVASCULAR hemolysis that occurs in response to blood antigen

Question 2

List the major clinical effects of acute hemolytic transfusion reactions. What is the difference between mild and severe acute hemolytic transfusion reaction?

Answer 2

Mild= fever, chills, rigors

Severe=

• Abdominal, chest, flank, and back pain
• Hypotension, dyspnea, shock
• DIC

May see Hemoglobunira in unconscious or anesthetized patient

Question 3

What is the most effective method to prevent acute hemolytic transfusion reactions?

Answer 3

Minimize human clerical errors by:

• Multiple checks
• Technology e.g. hand-held scanners…etc.

Question 4

List the clinical symptoms of delayed transfusion reactions.

Answer 4

• Occurs days to week after transfusion
• EXTRAVASCULAR HEMOYLSIS causing:
  1) Anemia
  2) Jaundice

Question 5

What are the lab findings of delayed hemolytic transfusion reactions?

Answer 5

Anemia

Question 6

What are the three major clinical situations in which Rh immune globulin should be given to prevent HDN?

Answer 6

1) Mother is Rh- and Dad is Rh+
2) Mother is Rh- and Dad’s status is unknown
3) Infant is known to be Rh+

Question 7

What is the most common reaction to transfused blood? What causes it?

Answer 7

Fever

• Leukocytes in product release cytokines that accumulate
• Patient antibodies to leukocytes induce fever

Question 8

What are the adverse consequences of transfusion that may first manifest as fever?

Answer 8

1) TRALI
2) Acute hemolytic transfusion reaction
3) TA-GVHD
4) TTBI (transfusion transmitted bacterial infection)

Note that premedication with acetaminophen may mask fever/ initial presentation*

Question 9

Describe the presentation of Transfusion-Associated Acute Lung Injury (TRALI).

Answer 9

Fever 
Dyspnea 
Cyanosis 
Hypotension
Acute pulmonary edema 

All occurs WITHIN 6 HOURS of transfusion

Question 10

What causes TRALI?

Answer 10

Two-HIT mechanism that occurs with plasma or platelets

1) Neutrophil sequestration and priming
- Injury to the microvasculature in the lungs
- Neutrophils accumulate at the site of injury, called “sequestration”
- Neutrophils are shifted into a “primed state” and respond to previously INNOCUOUS stimuli
2) Neutrophil activation occurs

–> Neutrophil release of cytokines, ROS, oxidases, and proteases causing pulmonary edema

Question 11

What is Transfusion Associated Graft Versus Host Disease?

Answer 11

• Blood donor has a different HLA-type from recipient

- T-cells in component see patient HLA antigens as foreign and attack

Question 12

Who is at risk for TA-GVHD?

Answer 12

Immunocompromised patients:

1) Leukemia
2) Lymphoma
3) Patient on immunosuppresive drugs
4) Neonates

Question 13

How is TA-GVHD prevented?

Answer 13

Irradiation of blood components

Question 14

What blood component is most likely to cause bacterial sepsis?

Answer 14

Platelets b/c they are stored at room temp. i.e. at a better temperature for bacterial growth

Question 15

Why do platelets cause bacterial sepsis?

Answer 15

Platelets are stored at room temp. i.e. at a better temperature for bacterial growth

Question 16

Why is directed donation not regarded as safer than volunteer donor blood?

Answer 16

The donor is more likely to be untruthful in screening b/c they want to help the patient

Question 17

What should you do if you suspect a transfusion reaction?

Answer 17

STOP the transfusion

1) Keep line open with saline
2) Do a “clerical recheck””
3) Contact physician

Question 18

How is Febrile TR prevented?

Answer 18

1) Leukoreduction*

2) Premedicate with acetaminophen

Question 19

What is the etiology of anaphylaxis seen in transfusion? What patient population is this relatively common in, in patients receiving transfusion?

Answer 19

• Patient has an antibody to something in the component

E.g. IgA deficient patient with an antibody to the IgA can develop anaphylaxis to transfusion

Question 20

Is pretreatment a good management for anaphylaxis?

Answer 20

No–pre-treatment does NOT work i.e. giving Benadryl will not prevent the reaction

Question 21

What is TACO?

Answer 21

Transfusion Associated Circulatory Overload

Occurs in patients that are already at risk of circulatory overload.

Question 22

What are the most common signs of TACO?

Answer 22

Increased BP and HR

There is nothing specifically diagnostic*

Question 23

What are the diagnostic criteria for TRALI?

Answer 23

1) No evidence of lung injury prior to transfusion
2) Onset within 6 hours of transfusion
3) Hypoxemia i.e. SaO2 less than 90% on room air
4) X-ray with bilateral infiltrates
5) No circulatory overload

Question 24

How is TRALI treated?

Answer 24

1) Supplemental oxygen
2) Pressors
3) NO DIURETICS

Question 25

What are the key distinguishing features of TACO and TRALI?

Answer 25

TACO=

• Patient at risk for volume overload
• Increased BP

TRALI=

• Fever and chills
• HYPOtension

Question 26

What is the classical antigen/ antibody combination that causes delayed hemolytic anemia?

Answer 26

• Kidd antigen and anti-kidd antibody

**vs. ABO in acute hemolysis*

Question 27

What percentage of TA-GVHD cases are fatal?

Answer 27

90%

Question 28

When are allergic transfusion reactions most common i.e. in response to what component therapy?

Answer 28

Plasma or platelets

Question 29

What are the two most common transfusion reactions?

Answer 29

Fever

TACO