Transfusion Medicine

Question 1

What blood components are available? 4

Answer 1

RBCs or packed RBCs
Platelet pool
Cryoprecipitate
Frozen plasma

Question 2

2 indications for RBC transfusion

Answer 2

Improved oxygen carrying capacity

Suppression of abnormal erythropoiesis

Question 3

Symptoms of someone who should get an RBC transfusion

Answer 3

Symptoms of anemia (SOB, angina, confusion, fatigue)
Acute blood losses
CUrrent Hb and chronicity of anemia or baseline anemia
Patient history and special situations

Question 4

What Hb levels are important to know for transfusion?

Answer 4

100: inappropriate to transfuse
<80: transfuse for symptoms of anemia only
<70: best threshold for the stable ICU adult/ped patient, adults with GI bleed

Question 5

2 things you NEED to do before transfusing

Answer 5

Order a group and screen

Obtain consent for transfusion

Question 6

What is a group and screen?

Answer 6

Typically done together
Group: tells us about ABO and D type. Test RBC and plasma separately
Screen: looking for non-ABO, alloantibodies. Test plasma

Question 7

Why do we care about ABO?

Answer 7

Tells us about histocompatibility

Critically important in transfusion safety, maternal fetal health, and organ transplantation

Question 8

Acute hemolytic transfusion reaction

Answer 8

From ABO incompatibility

One of 2 leading causes of death related to transfusion

Question 9

Why do we screen the plasma?

Answer 9

Patients may acquire alloantibodies following exposure to foreign RBC antigens by blood transfusion or pregnancy
Typically IgG antibodies
Positive result: antibody is present
Negative result: no alloantibody

Question 10

How long is a group and screen valid for?

Answer 10

96 hours

Plasma cells might produce an antibody over time if they are exposed to something

Question 11

Crossmatch

Answer 11

Final compatibility test before transfusion
Can be done via: immediate spin, indirect antiglobulin method, or computer assisted
Way of checking if that specific unit of blood will react with the patients blood

Question 12

TACO

Answer 12

Transfusion Associated Circulatory Overload
More common in elderly or pediatric populations
Overloaded with fluid and can get some pulmonary edema

Question 13

TRALI

Answer 13

Transfusion Related Acute Lung Injury

Question 14

Is postural dizziness a sign of anemia?

Answer 14

No

Its a sign of decreased vascular tone or fluid volume

Question 15

How quickly (in general) do you transfuse blood

Answer 15

Over 2 hours

Has to end in 4 hours

Question 16

What are the first 3 things you should do after you hear of a suspected transfusion reaction

Answer 16

Stop the transfusion
Go see the patient
ABCDs

Question 17

Acute vs delayed reaction types

Answer 17

Greater or less than 24 hours

Can be immune, infectious or other

Question 18

Acute transfusion reactions

Answer 18

The signs and symptoms of severe, potentially life threatening transfusion reactions overlap with the signs and symptoms of minor transfusion rxns
Can see hives, itching, fever, chills, SOB/hypoxia, hypotension, shock, anxiety, chest or back pain, red/brown urine

Question 19

What is one set of conditions where giving platelets is potentially harmful

Answer 19

MAHAs (TTP, HUS, HIT)

Only consider giving them if there is significant bleeding

Question 20

3 indications to give plasma

Answer 20

Bleeding (or before a surgery) when the INR or PT is really high
Microvascular bleeding or massive blood loss
TTP