M15: Hydrops Flashcards
define hydrops
abnormal accumulation of serous fluid in at least 2 body cavities or 1 cavity w/ edema
it is the terminal stage for many conditions and signifies fetal decomposition
2 etiologies of hydrops
immune
non-immune
… hydrops is common, but specific etiology that causes hydrops is rare
on hydrops occurs, what is its rate of progression
rapid…. demise can occur w/in 24-48 hours
US appearance of hydrops
ascites pleural effusion pericardial effusion subcutaneous edema placental edema A-V doppler abnormalities low BPP score
why can ascites often be seen in the pelvis first
ascites can cause what pathology in the scrotum
most dependant part of the abdo cavity
hydrocele
describe pseudoascites
what can help us determine if its fluid
< 2 mm hypo ring that might be the hypo muscular layer of the abdominal wall
change probe angle and assess if its sitting in the most dependant location
what can pleural effusion cause
why
upper body edema
polyhydramnios
pulmonary hypoplasia
due to increased pressure on the mediastinum, thoracic vasculature and heart
where is subcutaneous edema usually first seen
what is anasarca
fetal scalp and face….. then abdo and limbs
general edema
what type of edema is a late sign of hydrops
placental edema
US appearance of placental edema
ground glass appearance and > 4 cm thick
whole placenta is thick: if hydrops is of fetal etiology
focal placental thickening: due to placental vascular malformation
pattern of immune hydrops
1st acites
2nd edema
3rd pleural and pericardial effusions
w/ thoracic abnormalities, where is hydrops seen first
what other abnormalities will this cause
seen as pleural and pericardial effusions
chylothorax and heart abnormalities
other names for immune hydrops
alloimmune hydrops
erythroblastosis fetalis
when does immune hydrops occur
when a rhesus mother has antibodies to fetal RBCs
maternal Rh - e.g. A- , or, O-
what is hemolysis
when would it occur
destruction of RBCs… (separation of hemoglobin from the RBCs, the hemoglobin would then be found in the plasma)
with a rhesus mother…. when maternal immunoglobulin antibodies cross the placenta and attack the antigen positive fetal RBCs
People who lack the Rh- lack what on their RBCs
They lack the RBC protein called rhesus factor
What % of immune hydrops is due to D antibodies
80%
What does the destruction of fetal RBCs cause
Anemia in the fetus - due to below normal level of erythrocytes
Fetal hepatosplenomagaly
Erythroblastosis fetalis
What is Erythroblastosis fetalis
Outpouring of many immature RBCs…. the immature RBCs don’t support of carry 02 well to tissue
What does Erythroblastosis fetalis cause
Tissue hypoxia
Hydrops
Cardiac failure
Demise
…. when the immature RBCs cant carry 02 to the tissue, fluid leaks out of cells causing hydrops… this leaking fluid doesn’t return to the heart so it has to work harder to compensate which causes the cardiac failure and demise
Steps to assessing immune hydrops
- Maternal antibody titers by blood test
- detailed fetal Us looking for hydrops
- MCA doppler… w/ severe anemia the velocity increases in the arteries due to decreased velocity of blood
- optical density determination (ODD) amnio is performed to assess bilirubin levels in amniotic fluid
Is MCA doppler reproducible and accurate
Yes
Treatment of immune hydrops
Fetal blood sampling and blood transfusions in utero (PUBS)
What % of hydropic fetuses will survive W/ intraventricular transfusions
Non-hydropic
70-85% of hydropic
85-95% of non-hydrops
When is non immune hydrops commonly seen in 1st and 2nd trimester
W/ spontaneously aborted fetuses
Common etiologies of non-immune hydrops in North American and Europe
Cardiovascular, infection, chromo
Common etiologies of non-immune hydrops in Southeast Asia
Homozygous thalassemia
What is Homozygous thalassemia
heterozygous thalassaemia
-Blood disorder not compatible w/ life…
if both parents pass the genes for this disorder to the fetus then the fetus has profound anemia resulting in death in utero.
-If only one parent passes the gene to the fetus, fetus would have mild RBC anomalies
Maternal causes of non-immune hydrops
Severe diabetes mellitus
Severe anemia
TORCH
Placental causes of non-immune hydrops
Chorioangioma (shunting)
Venous thrombosis
Cord tension
Fetal causes of non-immune hydrops
Many
Cardiac causes of NIH
Malformations
arrhythmia
High output failure from fetal shunts (TTTS)
Thorax and neck causes of NIH
Any anomaly of the chest that causes compression
Urinary causes of NIH
Prune belly
Chromosomal causes of NIH
45X0 - turners
T21, 18, 13
Triploidy
Other causes of non immune hydrops
Infection
Skeletal dysplasia
Fetal hypokinesis
Idiopathic
How do we investigate NIH
History - provide clues to ethology
Detailed scan for markers and anomalies
Fetal echo
Karyotype for chorom abnormalities and management
Fetal blood sampling and blood transfusion at the same time
What is FISH
What does it detect
Fluorescent in situation hybridization
Technique used to COUNT chromo for common aneuploidies
Only take 24-48 hrs
T21, 18, 13
What is cavity aspiration
Sample of fluid for a diagnosis of chylothorax
What is assessed after birth at NIH
Placenta
Once baby is diagnosed w/ hydrops, whats next
Assess changes to hydrops
Cardiothoracic ratios for cardiomegaly
Doppler for heart failure and to assess vessels for arterial pulsations w/ TR (IVC, PV and umbilical vein)… or you can do a colour assessment for TR
Therapy for NIH
Depends on etiology:
Arrhythmias - digoxin
Aneuploidy - no therapy
Non immune anemia -fetal blood transfusion is performed
Therapy for chylothorax and CCAM type 1 causing NIH
Pleural drainage to prevent pulmnary hypoplasia
Therapy for infections causing NIH
Antibiotics
Prognosis for NIH
Poor… termination is offered if NIH identifies in the 1st or early 2nd trimester
Antenatal therapy for NIH
Thoracentesis
Paracentessis
Therapy for TTTS
Serial therapeutic amniocentesis for recipient twin
Fetoscopic ablation of communicating vessels in the placenta
Cord occlusion w/ TRAP syndrome to prevent cardiac failure
