Rh Disease

Question 1

Carrying Rh D antigen =

Answer 1

Rh positive

Question 2

Reasons women still become alloimmunized?

Answer 2

1. Failure proper px

2. Spont fetal-mat hemorrhage (small)

Question 3

When to give Rhogam immoglobulin?

Answer 3

1. 28-29wks
2. w/i 72h post delivery (consider even if sterilization)
3. Threatened Ab/ SAb/ ETOP
4. External version
5. 2/3 tri bleeding
6. Molar preg/ ectopic
7. Amnio/ CVS

Question 4

What is Du?

Answer 4

weak D positive, does NOT need rhogam

Question 5

If threatened Ab prior to 12wks?

Answer 5

Controversial, some say DON’T need

Question 6

First trimester events?

Answer 6

If actual Ab, 50ug prior 12wks, 300 after

Question 7

2nd/ 3rd tri bleeding?

Answer 7

Mgmt controversial:

1. Consider indirect comb q3w -> + -> still has rhogam present, if - -> Kb to determine ant rhogam needed

Question 8

Post dates?

Answer 8

decision up to doc

Question 9

Risk of alloimmunz?

Answer 9

1. Mom NEGATIVE for antigen, & fetus is POSITIVE, therefore Mom dev Antibody
2. Previous positive prey, blood transfusion

Question 10

Indirect Coombs test?

Answer 10

It is OUR Ab screen test- sees Ab in SERUM

Question 11

Direct Coombs test?

Answer 11

See Ab’s on RBC’s surface

Question 12

Critical titer?**

Answer 12

1: 32 or more- via indirect coombs test

* *Only helps with first affected pregnancy! IF previous affected, NO titters!

Question 13

If non-critical titer?

Answer 13

If 1:8, or less, follow titers q4wks

Question 14

If 1:16?

Answer 14

Serial MCA dopplers starting at 24wks, if nml (MCA weekly until 35-36wks

Question 15

Definition hydrops?

Answer 15

1. Seen w/ Hgb <4

2. Excess fluid 2 compartments