RH LAB TEST, TREATMENT, PREVENTION

Question 1

Type the mother for ABO and Rh early in pregnancy.

Question 2

Mother’s serum is usually screened by means of the ______ to see if an antibody exists; if an antibody is found, it is identified and the titer determined. This titer
is rechecked throughout pregnancy as a monitor of the ________

Answer 2

indirect AHG test

possible severity of the disease.

Question 3

An increasing titer indicates an ________.

Answer 3

active immune response

Question 4

After _____,several tests can be performed on the child’s red cells, in addition to further
tests on the maternal serum.

Answer 4

birth,

Question 5

a sample of ______ is tested for ABO group and Rh type, and a ______ is performed.

Answer 5

umbilical cord RBCs

direct AHG test

Question 6

Other laboratory tests that may be performed on the child’s RBCs include:

Answer 6

hemoglobin determinations
blood smear examination 
differential
reticulocyte count
serum bilirubin determination

Question 7

The decision to perform _____ will depend on a combination of laboratory results and on the clinical condition of the child.

Answer 7

exchange transfusion

Question 8

Preparation can and should be made ______ birth so that the exchange can be done as
soon as possible if necessary.

Answer 8

before

Question 9

Acid elution technique (modified Kleihauer-Betke test)

Answer 9

Detection of Fetal Hemoglobin or Hemoglobin F (Hb F)

Question 10

this stain is based on the fact

that fetal hemoglobin is resistant to acid elution

Answer 10

Acid elution technique (modified Kleihauer-Betke test)

Question 11

this stain is based on the fact
that fetal hemoglobin is _____ to acid elution (separation of a substance by extraction), whereas adult hemoglobin is not; when a thin blood smear is exposed to an acid buffer, the adult RBC _______into the buffer, leaving only the RBC
stroma, but the _____is unaffected and retains its hemoglobin. The smears are
examined under the microscope after staining, and the _______ in the maternal RBCs is used to calculate the approximate volume of fetal hemorrhage into the maternal circulation

Answer 11

resistant
loses its hemoglobin
fetal RBC
percentage of fetal cells

Question 12

Chromatography:

_________for hemoglobins,

and _________ for globin chains

Answer 12

Ion-exchange HPLC

Reverse-phase HPLC

Question 13

______ based on antibodies against Hb F; it permits the distinction of true fetal cells, which contain Hb F as the _______, from maternal circulating F cells, which have lower cellular Hb F content.

Answer 13

Flow cytometry

major form of hemoglobin

Question 14

Treatment for infants with severe HDN includes _______.

Answer 14

RBC exchange transfusion

Question 15

a significant proportion of the child’s RBCs is replaced with transfused red cells.

Answer 15

exchange transfusion

Question 16

The exchange transfusion corrects the ______and removes the _______, at least temporarily, and can prevent brain damage. The procedure may need to be ________, depending on the level of bilirubin accumulation.

Answer 16

anemia
abnormal levels of serum bilirubin
repeated several times

Question 17

The type of RBCs used for transfusion depends on the _______.

Answer 17

antibody responsible for the

disease

Question 18

Use of ______ is the most common selection in exchange transfusion.

Answer 18

O-negative red cells

Question 19

The RBCs must be ______ for the antigen against which the antibody has been formed.

Answer 19

negative

Question 20

The child is given blood that is comparable with the ______.

Answer 20

mother

Question 21

In HDN caused by the formation of anti-D antibody in the mother’s serum, the child is
transfused with RBCs that are specific for the child’s own ABO type but _______ This is because not all the child’s blood is replaced at the time of exchange, and some maternal antibody is left. RBCs are given that will not react with the remaining antibody and will not harm the child.

Answer 21

negative for the D antigen.

Question 22

In an ______, packed RBCs are infused through the fetal abdominal wall into the peritoneum.

Answer 22

intrauterine transfusion

Question 23

Differentiate exchange transfusion and intrauterine transfusion.

Answer 23

Exchange transfusion is used as treatment for infants with severe HDN. While in an intrauterine transfusion, packed RBCs are infused through fetal abdominal wall into peritonuem

Question 24

Direct transfusion into the umbilical vein may also be attempted.

Answer 24

T

Question 25

Prevention of Rh Immunization

Answer 25

(Use of Rh Immune Globulin)

Question 26

If ____ is injected into Rh-negative women who deliver Rh-positive babies within ____ hours of delivery, they are well protected against Rh problems in subsequent pregnancies.

Answer 26

RhIg | 72

Question 27

The use of RhIg is based on interference with the recognition of the Rh antigen on the fetal cells by the mother’s immune system. This blocking interference prevents immunization (sensitization) by the fetus _____ RBCs. The mother is passively immunized by the administration of RhIg when recognition of _______(sensitization) by fetal RBCs is most likely.

Answer 27

Rh-positive | foreign antigen on the maternal RBCs

Question 27

The use of RhIg is based on interference with the recognition of the Rh antigen on the fetal cells by the mother’s immune system. This blocking interference prevents immunization (sensitization) by the fetus _____ RBCs. The mother is passively immunized by the administration of RhIg when recognition of _______(sensitization) by fetal RBCs is most likely.

Answer 27

Rh-positive | foreign antigen on the maternal RBCs

Question 28

Most exposure to fetal blood occurs at _____.

Answer 28

delivery

Question 29

RhIg is injected _____ within _____ hours of delivery in mothers: (1) _____ negative, (2) ________, and (3) _________

Answer 29

``` intramuscularly 72 (1) who are D (2) who have no detectable anti-D antibody (3) where newborns are D positive. ```

Question 30

_______ at __weeks’ gestation has also been advocated by the American College of Obstetricians and Gynecologists. If done, a sample of RBCs obtained immediately before treatment should be tested for _____, ______, ______ and identification of antibody, if present.

Answer 30

Antepartum treatment 28 ABO group, Rh type, antibody screen

Question 31

RhIg is supplied as a _____, _____, approximately _____ solution to be injected intramuscularly.

Answer 31

sterile, clear | 1ml solution

Question 32

RhIg is a concentrated solution (____ μg/mL) of _____ that may be derived from human _____.

Answer 32

300 IgG anti-D plasma

Question 33

It does not transmit hepatitis, HIV, or other detectable infectious diseases.

Answer 33

RhIg

Question 34

The anti-D antibody can be detected ______ after the administration of RhIg and is sometimes found for as long as ______ thereafter. If it is detected ______ after delivery, active immunization and failure of the RhIg can be assumed. Such failures are infrequent, but they can occur if RhIg is given _________or if Rh immunization has _____ during the pregnancy.

Answer 34

``` 12 to 60 hours 5 months 6 months too late or in too small a dose, RH immunization has already occurred ```

Question 35

If the amount of Rh-positive fetal RBCs entering the mother’s circulation is ___________, the standard dose of RhIg is not enough to prevent anti-D antibody formation. Thus, it is important to determine the presence and amount of ________. This may be done by ____ or enzyme-linked antiglobulin testing.

Answer 35

greater than 30 mL of whole blood fetomaternal hemorrhage acid elution