HDFN Flashcards
(36 cards)
Most common HDFN
ABO HDFN
Most severe HDFN
Rh HDFN
HDFN
a.k.a Erythroblastosis fetalis
Immune destruction of fetal red cells due to maternal antibodies from previous pregnancy
Pathphysio - Hydrops fetalis
In utero
Pathophysiology - Hydrops Fetalis
1. Anemia
2. Increased red cell production
2. 1. Erythroblasts in circulation
2. 2. Decreased protein
3. ** Increased erythropoiesis** (liver & spleen)
4. Hepatosplenomegaly
4. 1. Hypertension & Hepatocellular damage
5. High output cardiac failure w/ edema, ascites, effusion.
Pathophysio - Neonatal HDFN
at birth
Pathophysio - Neonatal HDFN
- Increased B1 (no conjugation)
- Jaundice
- Kernicterus (18-20 mg/dL B1)
- Permanent brain damage
18-20 mg/dl
B1
can cause Kernicterus and permanent brain damage
Condition for HDFN to occur:
* Mother:
* Fetus:
Condition for HDFN to occur:
* Mother: Rh negative
* Fetus: Rh positive
Others: Mother must have IgG antibodies from previous pregnancy
Common HDFN antibodies
Anti-D (95%)
Anti-K
ABO antibodies
< 1 mL
volume of fetal RBCs can immunize the mother
ABO HDFN
- First child:
- Predictable:
- Preventable:
- Spherocytes:
ABO HDFN
- First child: Affected
- Predictable: No
- Preventable: Yes
- Spherocytes: Yes
Rh HDFN
- First child:
- Predictable:
- Preventable:
- Spherocytes:
Rh HDFN
- First child: Not affected
- Predictable: Yes (Titer)
- Preventable: Yes
- Spherocytes: Rare
Cord Blood
Sample to condirm HDFN
10-12 weeks
2nd trimester
Fetal DNA Testing
identify coding genes for the antigens which cause HDFN
Saline Antiglobulin Tube Test
methos in antibody titer determination of HDFN
predict severity of HDFN
>16 Ab Titer
Critical Titer
proceed with proper management
2nd titer should be done at **18-20 weeks
> 32 Ab titer
Indicates to color doppler imaging
Antibody Titer
* >16
* >32
Antibody Titer
* >16 - Critical Titer
* >32 - indicates Color doppler imaging
O.D. 450
Collection: Amniocentesis & Cordocentesis
Bilirubin Testing
estimates the extent of fetal hemolysis
Middle Cerebral Artery-Peak Systolic Velocity (MCA-PSV) Ultrasonography
Predict anemia
based on the reduced viscosity at low hematocrit resulting to faster velocity
18-20 weeks
Amniocentesis for O.D. 450
HDFN Management
Intrauterine Transfusion
Transfusion of fetus in utero
Transfusion of PRBCs to the fetus (in utero) to **correct anemia **
Indication - Intratuterine Transfusion
Indication - Intratuterine Transfusion (one or more condition)
* Hemoglobin <10 mg/dL
* MCA-PSV indicates anemia
* Fetal hydrops on ultrasound
* High zone **(Zone II/Zone III) **in O.D. 450
Purpose - Intrauterine transfusion
Maintain >10 mg/dL of fetal hemoglobin
Exchange Transfusion
Transfusion of newborn infant
Removal maternal antibody and antigen negative RBCs to correct anemia and hyperbiliribunemia
