Lec 17 - Transfusion Reactions

Question 1

clinical use of Rh immune globulin

Answer 1

-prevents problems in future pregnancies

Question 2

historical significance of autologous donation

Answer 2

• youre more likely to get a transfusion if you donate your own blood for yourself
• usually donated before the surgery or whatever so the pt is slightly anemic = inc chances of ischemia
• usually blood isnt tested for viruses as much so then dont know if pt wants his virus laden blood or another donors blood

Question 3

historical significance of directed donation

Answer 3

-donating blood to some one you know

Question 4

hydrops fetalis basic mechanism and causes

Answer 4

imbalance of interstitial fluid production nd lymphatic return (caused by congestive heart failure, obstructed lymphatic flow, decreased plasma oncotic pressure)

body tries to compensate but ultimately increased venous pressure = edema and effusion

Question 5

consequences of accelerated RBC destruction:

Answer 5

hyperbillirubinemia (unconjugated) == kernicterus - yellow staining of the basal ganglia

Question 6

HDN caused by Rh antigens other than D

Answer 6

• Less immunogenic than D, so less severe

- Anti-E & C are most likely to cause severe HDFN

Question 7

Which non-Rh antibodies are most likely to cause significant HDFN?

Answer 7

Anti-Kell

-Kell antigen present on RBCs & erythroid precursors in marrow

Question 8

*Consequences of accelerated RBC destruction in HDFN

Answer 8

1. Hydrops fetalis
   - Accumulation of fluid in fetus (edema, effusion etc)
   - Many causes: Rh immunization, congenital heart disease, arrhythmia etc.
2. Kernicterus: Yellow staining of basal ganglia
   - Hyperbilirubinemia (unconjugated) from RBC destruction; immature liver can’t conjugate all

Question 9

Hydrops fetalis pathophysiology

Answer 9

Imbalanced interstitial fluid production & lymph return-> Body compensation-> ↑Venous P.-> ↑edema & effusion (cycle)

Question 10

Maternofetal hemorrhage occurs when/how?

Answer 10

• Mostly in last trimester & delivery

- Many other causes (abortion, trauma etc)

Question 11

*RhoGAM/ Rh immune globulin use & mechanism

Answer 11

• Prevent HDFN
• Unknown mechanism:
  1. The Anti-D masks antigen sites on fetal Rh+ cells in maternal circulation, preventing recognition
  2. The Anti-D Helps clear antibody-coated Rh+ cells before they can be recognized by maternal immune system

Question 12

When to administer RhoGAM

Answer 12

1. 28 weeks gestation
   (Rarely Rh alloimmunization before 28wk)
2. W/i 72hr. of delivery
3. Possible extra dose if beyond 40wk gestation

Question 13

Chance of developing Anti-D when D- pt. is transfused w/ D+ blood?

Answer 13

20%

Question 14

*Most common cause of HTR?

Answer 14

Clerical error

wrong label, wrong blood hung etc

Question 15

*Signs/symptoms of Acute intravascular HTR?

Answer 15

1. Fever/chills (80%)
2. Back/flank/infusion site pain
3. HypOtension/shock
4. Hemoglobinuria
5. “Impending sense of doom”

Question 16

Tx of acute intravascular HTR

Answer 16

• Hydration/diuresis (protect kidneys)

- Consider RBC exchange for high volume incompatible transfusions

Question 17

• Most frequently reported transfusion reaction (FNHTR)
• Sign/symptoms
• Tx

Answer 17

Febrile Non-hemolytic transfusion reaction

• Unexplained ↑temp. of 1C+, Chills, rigors
• Premedicated FNHTR (acetaminophen) can still have chills but not fever
• Tx= Acetaminophen

Question 18

*Schistocytes are present in ______ hemolysis

Answer 18

Intravascular
-Antibodies->complement->lysis
helmet cells

Question 19

most important factor when patient is having a hemolytic reaction to trasnfusion?

Answer 19

HOW MUCH BLOOD DID THEY GET?

STOP THE TRANSFUSION!

Question 20

What kind of RBC are present in extra vascular hemolysis?

Answer 20

SPHEROCYTES

-In extravascular, IgG coats-> Spleen/liver phagocytosis

Question 21

TACO is

Answer 21

a circulatory overload - gets better with diuretics

Question 22

TRALI is associated with

Answer 22

fever

does not get better with diuretics

Question 23

septic transfusion reaction most commonly involves…?

Answer 23

endotoxin making gram neg rods (yersinia or E Coli) from the donors blood

Question 24

platelets stored at room temp most commonly have what organsims?

Answer 24

gram pos cocci (staph epi and staph aureus)

another type of septic transfusion reaction

Question 25

symptoms of septic transfusion reaction?

Answer 25

fever
RIGORS (NOT CHILLS - MUSCLE TENSE UP A LOT!)
shock