Amniotic Fluid

Question 1

Causes of oligohydramnios

Answer 1

PROM
Renal agenesis
Bladder output obstruction
ACEi
NSAIDs 
Preeclampsia
Smoking
NTD

Question 2

Causes of polyhydramnios

Answer 2

Mostly idiopathic
DM
Hydrops fetalis
Multiple pregnancy
GI obstruction e.g duodenal atresia 
Oesophageal obstruction
TORCH infections

Question 3

Amniotic fluid production and absorption

Answer 3

Produced by fetal urine (maj) and lung fluid (min) after 8 weeks gestation. Initially transudation.
Absorbed by fetal swallowing (maj) and blood absorption (min) after 8 weeks gestation. Initially passive.

Question 4

Measurement of liquor volume

Answer 4

USS

Calculating from sum of vertical pockets of fluid in 4 quadrants of uterus (AF index)

Question 5

Definition of oligohydramnios using AFI

Answer 5

AFI<5th percentile for gestation

Question 6

Definition of polyhydramnios using AFI

Answer 6

AFI>95th percentile for gestation

Question 7

Complications of oligohydramnios

Answer 7

Amniotic band syndrome resulting in serious deformities - adhesions between fetus and amnion
Uterine compression causing MSK deformities
Lung hypoplasia
Potters syndrome

Question 8

Complications of polyhydramnios

Answer 8

Maternal dyspnoea
Malpresentation
Cord prolapse
Placental abruption

Question 9

Management of oligohydramnios

Answer 9

Can infuse crystalloid solution into amniotic cavity during labour if abnormal CTG and want to avoid C/S

Question 10

Management of polyhydramnios

Answer 10

Controlled amniotomy during labour to decrease risk of cord prolapse and placental abruption with rapid decompression
Indomethacin (NSAID) before 32 weeks

Question 11

Management of amniotic fluid embolus

Answer 11

Deliver baby in 5 mins
Cardiac arrest protocol
Diagnosed post-mortem