side dishes Flashcards
(124 cards)
1
Q
what does the placenta do
A
transports nutrients and oxygen to fetus
removes waste from fetus
produces hormones to sustain pregnancy
forms barrier between mat and fetal blood
2
Q
placental is fully formed by __ GA
A
16-18w
3
Q
fetal trophoblast becomes __
A
chorionic villi (frondosum)
4
Q
maternal decidua becomes __
A
decidua basalis
5
Q
placenta made up of __ cotyldons divided by septa
A
15-20
6
Q
chorionic plate vs. basal plate
A
chorionic = fetal side
basal = maternal
7
Q
grade 3 placenta prior to 36w GA is associated with __
A
advanced IUGR
sig mat HTN
heavy smoking
8
Q
normal mean placental thickness roughly equal to __
A
weeks GA
> 4cm abnormal
- measure from chorionic to basal plate
9
Q
thick HETEROGENEOUS placenta associated with __
A
tirploidy
molar pregnancy
placental hemorrhage
fetal viral infections (oft with calcs)
10
Q
thick, HOMOGENEOUS placenta associated with __
A
gestational DM
fetal hydrops
fetal viral infections (with calcs)
mat anemia
aneuploidy
11
Q
thin placenta associated with __
A
mat HTN
chromosomal abnormalities
polyhydramnios
severe IUGR
advanced DM preconception
severe intrauterine infection
placenta membranacea
12
Q
most hypoechoic lesions within placenta are __
A
venous lakes
** maternal blood
rouleau
13
Q
placental lake aka
A
sonolucencies
hole
lucencies
** not lacunae??
14
Q
most common placental tumour
A
choriocarcinoma
- benign
15
Q
sono features of choriocarcinoma
A
solid mass with variable echo pattern bulging at fetal surface (chorionic) of placenta
variable doppler (sometimes avascular)
+/- polyhydramnios
fetus normal or signs of hydrops
*** large >5cm associated with fetal CHF, IUGR and nonimmune hydrops
16
Q
which placental tumour may elevate MSAFP
A
choriocarcinoma
17
Q
a placenta which partially or completely covers the internal os of the cervix; degrees
A
placenta previa
complete
partial
marginal
low lying <2cm
18
Q
placental migration aka
A
dynamic placentation
TROPHOTROPISM
normal migration from internal OS with progression of pregnancy
“grows toward nourishment” at fundus of uterus (better blood supply)
19
Q
a normally implanted placenta that prematurely separates from the uterine wall
A
abruptio placenta
- mild to severe
20
Q
clinical signs of placental abruption
A
mild tenderness to rigidity
+/- bleeding
elevated MSAFP
21
Q
risks for abruptio placenta
A
mat HTN
PROM
short umb cord
advanced mat age
previous abruption
abdominal trauma
smoking/cocaine
retroplacental myoma
22
Q
fetal complications associated with abruptio placenta
A
fetal hypoxia
IUGR
premature delivery
demise
23
Q
maternal complications of abruptio placenta
A
hypovolemic shock/cardiac arrest
* state of decreased blood volume
acute renal failure
disseminated intravascular coagulopathy
* excessive clotting throughout body
24
Q
type of abruptio placenta
A
retroplacental
marginal
25
'sono features of abruptio placenta
hematoma appearance either retroplacental or subchorionic
may appear normal if blod is freely escaping the uterus
* could be bleeding in a way that is not detectable
26
placenta accreta spectrum aka
placenta creta
placental invasion
morbidly adherent placenta (MAP)
accreta, increta, percreta
27
deficiency of decidua basalis
underdeveloped dicidua basalis allows varying degrees of invasion of chorionic villi into myometrium
replaced with connective tissue
accreta, increta, percreta
28
chorionic villi attach to the myometrium; most common form of placental invasion
placenta accreta
29
chorionic villi extend INTO the myometrium
placenta increta
30
chorionic villi penetrate THROUGH the uterine wall (ie into bladder)
placenta percreta
"past"
31
risk factors for placental invasion
previous csec
anterior placental previa/ low lying
hx of ut sx
increased parity
elevated MSAFP
32
sono findings for placental invasion in 1st trimester
may see GS location in csec scar
multiple irregular vascular spaces within placenta
colour usually intense blood flow within anechoic placental space (due to direct association with ut arteries)
33
sono features of placental invasion in 2nd/3rd trimester
multiple vascular lacunae
loss of normal hypoechoic retroplacental zone
* check angle of probe; can be angle dependent
** retroplacental myometrium should be >1mm
**pitfall, retroplacental zone may not be seen with normal anterior placenta (false positive)
extensive villi into myometrium, serosa, or baldder
abnormal uterine serosa-bladder interface
34
secondary placental lobe(s) attached to main body by velamentous connection
succenturiate lobe
35
significant associated risks for succenturiate lobe(s)
antepartum bleeding
vasa or placenta previa
fetal distress due to trauma to interconnecting vessels
postpartum bleed (retention)
36
succenturiate variant where two similarly sized placental lobes are present with vascular connection
bilobed placenta
ddx FMC, SCH
37
smooth chorion insertion into chorionic plate closer to the centre of the placenta than at the margin resulting in chorionic plate being smaller than basal plate
extrachorial placenta
partial (asymptomatic) or
complete (entire edge of placenta)
* associated with antepartum bleeding, preterm labour, placental abruption and IUGR
- circumvallate
- circummarginate
38
smooth chorion inserts closer to the centre of placenta and rolls UP
circumvallate placenta
ddx synechiae, ut septum, amniotic band syndrome
39
smooth chorion inserts closer to the centre of placenta and often not seen with ultrasound
circummarginate placenta
flat interface
'spread like margerine'
40
LAX, circumvallate placental edges appear __ and SAX the edges appear __
LAX -> long
SAX -> short
41
a thin, membranous placenta occupying the entire periphery of the chorion (covering most or entire uterine wall)
placenta membranacea
decidua capsularis did not flattern the chorionic villi
placenta usually thinner than normal
42
placenta membranacea associated with __
invasion and placenta/vasa previa
43
CI at edge of placenta
battledore insertion
44
Ci away from placenta into membranes
velamentous CI
45
cylindrical shaped placenta (ring)
annularis placenta
46
thinning/ hole in middle of placental tissue
fenestrata placenta
47
embryonic diverticulum from YS to body stalk that becomes blind-ended tube from bladder to umb cord in fetus
allantois
-> urachus
-> median umbilical ligament
48
embryonic connection from midgut to YS that narrows and disappears by 9w GA
vitelline duct
-> Meckel diverticulum if not obliterated in utero (slight bulge in small intestine)
49
umb vein brings blood __ fetus and the umbilical arteries __ the fetus
vein TO the fetus
arteries RETURN to placenta
50
arteries are protected and insulated by __
Wharton's jelly
covered by amnion
51
normal cord length full term
55cm, 1-3cm thick
52
short umb cord associated with
fetal movement disorders
placental abruption
cord rupture (subsequent demise)
53
long umb cord associated with
fetal entanglement
true knots
thrombi
54
normal umb coiling index (UCI)
~0.44 coils/ cm
55
hypercoiled umb cord associated with
increased incidence of premature delivery
occlusion in cases with entanglement
low arterial pH
asphyxia
**usually associated with cocaine withdrawal issues
56
undercoiled umb cord associated with
kinking, compression
low APGAR score
57
associated risks if 2VC not an isolated finding
fetal anomalies (cardiac, renal)
IUGR
aneuploidy
velamentous CI
preterm delivery
58
eccentric CI __ cm from edge
>2cm but still off centre
59
marginal insertion __ cm from edge
<2cm
can progress to velamentous Co and vasa previa
60
associated risks with velamentous CI
no wharton's jelly (vessel compression)
vasa previa
hemorrhage
61
associated findings with velamentous CI
esophageal atresia
VSD
2VC
succenturiate placenta
low brith weight, cleft palate, hip dislocation/dysplasia, asymmetrical head shape, spina bifida
62
pulse of velamentous CI will match __ heart rate
fetal
confirms not maternal vessels
63
common umb cord masses
cysts
neoplasm
knots
- false (kink)
- true (polyydramnios, increased risks fetal loss)
hematoma
focal edema
64
t/f single loop of cord around fetal neck is not cause for concern
true
if many, can cause cord shortening and the associated risks of that
asphyxia
management is close surveillance (count fetal movement, etc)
65
PROM with cord prolapse; look for __
extent
= ruptured membranes and can restrict or occlude blood flow to fetus (compression)
***** obs emergency
66
causes for cord prolapse
abnormal presentation of fetus
LONG cord
polyhydramnios
prematurity
twins
***** obs emergency
67
cord wrapped around neck aka
nuchal cord
68
causes for cord compression
oligohydramnios
nuchal cord loops
true knots
compression by fetus (ie. prolapsed cord, undercoiled cord)
SHORT cord
69
what are the pregnancy membranes
amnion and chorion
amniochorionic membrane
wall preventing fluid from leaving too early "impermeable to amniotic fluid"
70
__ membrane develops from trophoblast and is surrounding blasocyst
chorion
71
outer blastocyst divides into 2 layers of trophoblast; they are __
syncytiotrophoblast (outer)
** future placenta
- dissolves endo to fuse to what is now decidua basalic
cytotrophoblast (inner)
** future smooth chorion
- decidua capsularis
72
__ membrane forms adj to embryonic disc within blastocyst
amnion
73
as gest sac explands, __ contacts decidua parietalis and fuses during 2nd trimester
amnion
74
when amnion fuses to decidua parietalis, the uterine cavity is __
obliterated
75
shelf vs sheet vs strand
shelf = indenting synechiae, circumvallate placenta, ut septum
sheet = compartments
** line no matter how you rotate
strand = linear membrane cause for amniotic band syndrome; sticky when rupture early
** dot when you rotate
76
fetal development outside of amniotic cavity secondary to late rupture of amnion
extra-amniotic pregnancy
associated with SHEET septation
77
septation sheets can be normal if separation occurs __ GA
< 16w GA
78
amniochorionic membrane lifting from ut wall by subchorionic hematoma
abnormal septation sheet
can cause compartments and issues
79
which membranous septation drapes over an anatomic ridge (ie. synechiae)
amniochorionic shelf
80
vascularity of septations
avascular
some SHELVES have vascularity depending on type of anatomical adhesion (ie. uterine septation)
81
amnion abuts the chorion around __ GA and amnion fuses with chorion around __ GA
abuts at 12-16w GA
fuses 20w GA
82
chorionic cavity between amnion and chorion
subamniotic space
* not continuous with uterine cavity
83
uterine cavity between chorionic membrane and uterine wall
subchorionic
*fluid can leak to cervical cavity
84
potential spaces for blood collection
subchorionic (uterine cavity)
retroplacental
subamniotic (chorionic cavity)
amniotic cavity
85
subchorionic hemorrhage aka
subchorionic hematoma
86
subchorionic bleeds aka
marginal placental abruption
*premature detachment at edge of placenta
87
separation of amnion and chorion membranes
amniochorionic separation
*primary and secondary
88
who regulates the amniotic fluid
fetus is the regulatory apparatus
89
__ produces amniotic fluid
chorion plate of placenta
skin
urinary tract
respiratory tract
90
__ removes amniotic fluid
GI tract
respiratory tract
uterine wall
91
__ are the primary source of amniotic fluid after 16w GA
kidneys
92
amniotic fluid peaks at __ GA and drastically reduces after __ GA
peaks at 30-36w
decreases after 42w
93
SDP
2-8 cm
94
AFI
10-20 cm
* MB 8-18 cm
95
fetal causes for oligohydramnios
triploidy
kidney problems
bladder outlet obstruction
96
maternal causes for oligohydramnios
PROM
IUGR (shit placenta, HTN, drugs)
97
placental causes for oligohydramnios
insufficiency
twin to twin transfusion syndrome (DA)
** donor twin has IUGR
recipient hydrops
98
fetal complications with oligohydramnios
pulmonary hypoplasia
* bell shaped chest
distress (cord compression; asphyxia)
clubfoot
dolichocephaly
99
management of oligohydramnios
amnioinfusion
* injection of saline
100
most common cause for polyhydramnios
idiopathic
101
fetal causes for polyhydramnios
CNS lesion
open NTD
upper GI atresias or bowel obstruction
dandy walker malformation
shit lungs, esophageal compression
CHF
skeletal dysplasia
unilat renal agenesis
102
expected AFI with unilat renal agenesis
polyhydramnios
* paradoxical increase of amniotic fluid
103
expected AFI with upper GI atresia
polyhydramnios
104
maternal causes for polyhydramnios
DM
hydrops (immune and non immune)
105
expected AFI with mat DM
polyhydramnios
106
expected AFI with mat HTN
oligohydramnios
** fetal IUGR
107
expected AFI with dandy walker malformation
polyhydramnios
108
placental causes for polyhydramnios
twin to twin transfusion
** recipient twin hydropic with polyhydramnios
can be MCDA (stuck twin gets oligo, other twin poly)
large placental chorioangioma
- fluid overload and fetal CHF
109
features of placenta with polyhydramnios
thin placenta in severe cases
+/- cervical incompetence
110
severe polyhydramnios SDP and AFI
> 16 cm
AFI >/= 35 cm
111
management severe polyhydramnios
therapeutic amniocentesis
indomethacin therapy
112
maternal clinical presentation with severe polyhydramnios
overdistended ut resultant preterm labour
SOB
insomnia
leg edema
supine hypotensive syndrome
113
physiological sources of amniotic fluid echoes
desquamated fetal cells (epithelial)
venix caseosa (covering on fetal skin)
meconium (poop?)
114
sludge in amniotic fluid risk for __
PROM and chorioamnionitis
115
cervix length
>3cm TAS
>2.5cm EVS
116
cause for congenital incompetence of cervix
DES exposure
isolated idiopathic
connective tissue disorder
** ie rheumatoid arthritis, lupus, sclerosis
117
progressive severity of cervical incompetence
T
Y
V
U
118
what GA is it okay to perform cervical stress test
15-24w GA
119
most common suture technique for cervical cerclage
McDonald 'purse stringe'
120
preterm is __ GA
<37w
121
post dates is __ GA
>42w
122
fetal vessels crossing IO, situating between presenting part of fetus and cervix
vasa previa
123
partial separation (opening) of myometrium at the location of uterine scar (ie csec)
uterine dehiscence
*risk of rupture
124
what length of uterine dehiscence is considered at risk of rupture
<3mm AP
