Flashcards in EXAM #2: TRANSFUSION REACTIONS Deck (29):
What are acute hemolytic transfusion reactions?
INTRAVASCULAR hemolysis that occurs in response to blood antigen
List the major clinical effects of acute hemolytic transfusion reactions. What is the difference between mild and severe acute hemolytic transfusion reaction?
Mild= fever, chills, rigors
- Abdominal, chest, flank, and back pain
- Hypotension, dyspnea, shock
****May see Hemoglobunira in unconscious or anesthetized patient****
What is the most effective method to prevent acute hemolytic transfusion reactions?
Minimize human clerical errors by:
- Multiple checks
- Technology e.g. hand-held scanners...etc.
List the clinical symptoms of delayed transfusion reactions.
- Occurs days to week after transfusion
- EXTRAVASCULAR HEMOYLSIS causing:
What are the lab findings of delayed hemolytic transfusion reactions?
What are the three major clinical situations in which Rh immune globulin should be given to prevent HDN?
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+
What is the most common reaction to transfused blood? What causes it?
- Leukocytes in product release cytokines that accumulate
- Patient antibodies to leukocytes induce fever
What are the adverse consequences of transfusion that may first manifest as fever?
2) Acute hemolytic transfusion reaction
4) TTBI (transfusion transmitted bacterial infection)
****Note that premedication with acetaminophen may mask fever/ initial presentation*****
Describe the presentation of Transfusion-Associated Acute Lung Injury (TRALI).
Acute pulmonary edema
****All occurs WITHIN 6 HOURS of transfusion****
What causes TRALI?
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
What is Transfusion Associated Graft Versus Host Disease?
- Blood donor has a different HLA-type from recipient
- T-cells in component see patient HLA antigens as foreign and attack
Who is at risk for TA-GVHD?
3) Patient on immunosuppresive drugs
How is TA-GVHD prevented?
Irradiation of blood components
What blood component is most likely to cause bacterial sepsis?
Platelets b/c they are stored at room temp. i.e. at a better temperature for bacterial growth
Why do platelets cause bacterial sepsis?
Platelets are stored at room temp. i.e. at a better temperature for bacterial growth
Why is directed donation not regarded as safer than volunteer donor blood?
The donor is more likely to be untruthful in screening b/c they want to help the patient
What should you do if you suspect a transfusion reaction?
STOP the transfusion
1) Keep line open with saline
2) Do a "clerical recheck""
3) Contact physician
How is Febrile TR prevented?
2) Premedicate with acetaminophen
What is the etiology of anaphylaxis seen in transfusion? What patient population is this relatively common in, in patients receiving transfusion?
- 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
Is pretreatment a good management for anaphylaxis?
No--pre-treatment does NOT work i.e. giving Benadryl will not prevent the reaction
What is TACO?
Transfusion Associated Circulatory Overload
*****Occurs in patients that are already at risk of circulatory overload.*****
What are the most common signs of TACO?
Increased BP and HR
****There is nothing specifically diagnostic*****
What are the diagnostic criteria for TRALI?
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
How is TRALI treated?
1) Supplemental oxygen
3) NO DIURETICS
What are the key distinguishing features of TACO and TRALI?
- Patient at risk for volume overload
- Increased BP
- Fever and chills
What is the classical antigen/ antibody combination that causes delayed hemolytic anemia?
- Kidd antigen and anti-kidd antibody
*****vs. ABO in acute hemolysis****
What percentage of TA-GVHD cases are fatal?
When are allergic transfusion reactions most common i.e. in response to what component therapy?
Plasma or platelets