Amniotic fluid pathology Flashcards
How the amniotic fluid appear on US?
Hypoechogenic
main role of amniotic fluid
protection agaisnt infection and uterine compression ….
2 period of AF in pregnancy?
Why there is 2 periods?
why do they differ?
-up to 20th week
then from 20th week till end
-because source AF is different between the 2 stages
-because in second stage the skin become impermeable (keratinization) while fetogenesis continue mainly in GI kidney and lungs
During the first period:
-AF is —osmolar
-the composition of AF is same as—-
-as early as —–weeks of amenorrhea the fetal kidney is the main source
-isoosmolar
-fetal serum (skin of fetus is permeable to water sodium and chlorine)
-12th-13th (no keratinization before it)
During second part:
-the AF comes mainly from—
-Its—osmolar
fetus urine
hypoosmolar
T or F
-the osmolarity changes in case of hydramnios
-Diuresis (1ml/h) reaches 600 to 1200ml per 24hr at end of pregnancy
-The AF decreases during first 20 weeks
-Slow decrease from peak at 32-33 weeks then fast decrease 39-40 weeks
-In amniocentesis it will be reestablished within 24hr
In post term preg starting from 37 weeks fluid starts to decrease rapidly which affects the decision to deliver the baby
F(constant)
F(0.7ml/hr)
F(increase)
T
T
F (from 39-40w)
t or F
-Antiprostaglandins causes anuria
-Lungs begin to secrete as early as 15 weeks
-The lung secretion reaches 300 ml at end of preg which allows larynx opening and passage of surfactant
T
F (18th but still the kidney is the main source)
T
Regarding L/S ratio
if >—-then its a good indicator for fetal maturity
Used in case of (f/u or without F/U)
2
not followed up
US is most precise in —-trimester +—-days
——trimester+-2-3weeks
—–trimester+-1-2weeks
1st 3days
3rd
2nd
synthesis of Af is by —–and….
amnion and chorion
the amnion has large vascularization
false the chorion
the chorion is a …. membrane with numerous….but with evidence of ……
……has receptors in chorion and passes into….
AF at beginning has the same weight as….. it decreases over time to reach….. but must nor exceed….
semi-permeable
pores
protein synthesis
prolactin-amniotic cavity
as the fetus-1000ml-2000ml
Oligoamnios:
-defined as <…..ml (volume or as US finding)
_discovered thru….
we must search for—-
-clinically the fetus is difficult to —–by—–
-is this sign enough for diagnosis?
200ml , Real volume
US
malformations
-palpate by leopolds maneuver
suspection not Dx
in oligoamnios:
AFI:….
DVP:…
Factor of prognosis:…..especially <…..
Fetus will be….with signs of ….
if in doubt of fetal morpho ……
<5cm
<3cm or even <1cm
compression of lungs , <26wks
compressed and in hyperflexion
instillation of saline
by definition
DVP is…..
AFI….
-Largest vertical fluid without fetal parts or UC
-sum of 4 pockets (4 measurments)
DD of oligoamnios:
PROM (but usually we have other sx like contractions or fever)
Etiologies of Oligoamnios:
1-
2-
3-
1-organic: severe bilateral renal agenesis (potter)
2-Organic: Polymalformative syndrome (prune belly)
3-Functional: insufficiency of placental perfusion
T or F
The early oligoamnios of 2nd trimester ….dominates with …..prognosis
the oligo of 2nd or 3rd where…..is the main cause with …..prognosis
malfomation/poorer prognosis
Growth retardation by insuff of perfusion/better
List some diseases that happen in 2nd or 3rd trimester that causes oligoamnios
vasculo-renal syndromes
Biamniotic monochorionic twin preg (TTTTS)
Single UA
Smoking
Indomethacin
Hypothyroidism
Post-term
Biophysical score is done by:…..and….
the 5 parameters are:
the most important:
NST and US
AFI,fetal tone,motricity,respiratory mvts + NST
AFI
Hydramnios or polyhydramnios:
-DEfinition:
-Sx:
-AFI:……DVP:……mild:…moderate….severe….
-Amniotic volume exceeding 2L
-Nausea-vomitting and abdominal pain
->25cm >8cm
-8-11 12-15 >16
Etiologies of hydramnios:
1-
2-
3-
4-
5-
6-
7-
1-twin pregnancy (monozygotic)
2-Fetal malformations :anenceohaly,spina,atresia of eso,duodenal stenosis,abdominal muscle atresia (prune belly),omphalocele,gastroschisis anasarca and poly malformations
3-anomalies of cord: nodes, angioma, agenesis of UA
4-Infection: Torch
5-hemolytic disease results in anasarca
6-Diabetes (osmotic diuresis)
7-Toxemia and preeclampsia
T or F
Fetal causes are the most common etiology of Hydramnios
T
2 presentations of hydramnios:
-very fast (acute) early poor prognosis 4th-6th ,always pathological egg (monoamnion monozygotic or serious fetal abnor) , pain,vomitting,insomnia,cyanosis,tachy, it terminates spon or we terminate it
-2nd is more common and evolution is slow we feel like we are touching an ice cube when we palpate the baby delivery occurs premature with: long labor,UC prolapse and increased risk of PP hemorrhage due to overdistended uterus
