M14: Amniotic Fluid

Question 1

purpose of amniotic fluid

Answer 1

• protects from physical trauma
• provides stable temp for the fetus and allow normal growth and develop of bones and muscles
• helps w/ the maturation of lungs and GI
• may provide some nurtients

Question 2

what produces amniotic fluid in very early preg

what about first trimester

Answer 2

mostly from the chorioamniotic membranes

chorion frondosum, membranes, skin, lungs, GU tract

Question 3

what produces amniotic fluid in 2nd and 3rd trimester

Answer 3

kidneys, sm amount from the lungs

Question 4

where is amniotic fluid reabsorbed

Answer 4

sm bowel

Question 5

how will high GI obstructions or swelling defects affect amniotic fluid

Answer 5

polyhydramnios

Question 6

what will bilateral GU obstructions or renal agenesis affect amniotic fluid

Answer 6

oligohydramnios

Question 7

define polyhydramnios

Answer 7

vertical pocket >8 cm

AFI >25 cm

Question 8

normal AFI

Answer 8

b/w 5-25 cm

Question 9

when is the maximum amniotic fluid level reached, and then maintained

when does the fluid level slowly start to diminish

Answer 9

max is 22 weeks, maintained until 34 wks

34 wks

Question 10

an amniotic fluid pocket of what size is required for fetal breathing

Answer 10

1 cm

Question 11

how is AFI measured

Answer 11

the largest pocket of fluid in each quadrant is added together

Question 12

how is poly subjectively determined

Answer 12

when the fetus is seeing floating freely in the amniotic fluid…. fetus should be touching at least 2 sides of the uterus

Question 13

causes of polyhydramnios

Answer 13

diabetes mellitus (most common cause)
CNS
hydrops
TTTS (recipient)
musculoskeletal dysplasia

Question 14

what can poly cause

Answer 14

maternal pain or SOB
PROM
preterm delivery

Question 15

treatments for polyhydramnios

Answer 15

amniocentesis until the largest pocket is < 8 cm

indomethacin - prostaglandin inhibitor which decreases fetal urine output

Question 16

complications of amniocentesis

Answer 16

PROM
preterm delivery
infection

Question 17

complications of indomethacin

when would it be given

Answer 17

premature closure of ductus arteriosus

early preg, not near term

Question 18

define oligohydramnious

Answer 18

AFI < 5 cm

largest pocket < 2 X 2 cm

Question 19

how to calculate oligo in the 1st trimester from 5.5 - 9 wks

Answer 19

MSD (mm) - CRL (mm) = < 5 mm is oligo

Question 20

causes of oligo

Answer 20

PROM
IUGR
renal anomalies
post dates
abruption
TTTS (donor twin)

Question 21

what can oligohydramnios cause

Answer 21

limb anomalies (club foot)
pulmonary hypoplasia
restricted growth