Amniotic Fluid Flashcards
What does amniotic fluid allow for baby? 6
- Provides protection from physical trauma
- Allows for growth
- Provides a stable temperature for the fetus
- Enables normal development of bones and muscles by facilitating room for movement
- AIDS in the maturation of lungs and GI tract
- Provides some nutrients, hormones and antibodies
What is amniotic fluid produced by in the first trimester? 5
- Chorion frondosum
- Membranes
- Skin
- GU tract
- Lungs
In early pregnancy main from chorioamniotic membranes
In the 2nd and 3rd trimester Production of amniotic fluid is produced by what? 2
- Kidneys
- Small amount from lungs
Removal of amniotic fluid is done how?
Fetus drinking the fluid
What is the process of amniotic fluids in gestation? 3
- The fetus drinks the amniotic fluid
- Fluid foes through the fetal GI tract, and is absorbed by the bowel
- The fetal kidneys excrete urine back into the amniotic cavity
During the amniotic fluid process, any high GI obstructions or Swallowing deficits cause what?
Polyhydramnios
In terms of amniotic fluid process, any bilateral GU obstructions or renal agenesis causes what?
Oligiohydramnios
When looking at amniotic fluid volume, what is the most important point?
Experienced observer
How do we measure amniotic fluid volume?
Maximum vertical pocket
What is the maximum vertical pocket?
Deepest pocket that is free of the umbilical cord or fetal
Amniotic fluid index (AFI) is what?
Largest pocket in quadrant is added together
What is the normal level for AFI?
5-25cm
What is the depth of the largest visible pocket for a normal vessel?
2 < X < 8 cm
Maximum amniotic fluid is reached when? And when is it maintained? (weeks)
At 22 weeks and maintained at 34 weeks
After which week does AFI start to diminish slowly?
34 weeks
How much of a pocket is needed/ required for fetal breathing?
1cm
What does this image demonstrate?
AFI measurements in the four quadrants
What does polyhydramnios look like subjectively? 2
- The fetus floats freely in the amniotic fluid
- Fetus should be touching the uterus on at least 2 sides normally
How deep is the Polydramnios pocket?
> 8 cm pocket
What is the AFI for Polyhydramnios?
> 25 cm AFI
What does this image demonstrate?
Polyhydramnios, the deepest amniotic pocket is >8cm
What does this image demonstrate?
Polyhydramnios, AFI is >25cm
What are some causes of polyhydramnios? 7
- Diabetes mellitus
- CNS - NTD
- High GI obstruction
- Hydrops
- Twin to twin transfusion syndrome
- MSK Dysplasia
- Idiopathic
What is the most common cause of polyhydramnios?
Diabetes mellitus
What might polyhydramnios cause? 4
- Maternal abdominal pain
- Maternal SOB
- PROM
- Preterm delivery
How does polyhydramnios cause PROM?
Due to the uterus expanding so quickly
How does polyhydramnios cause preterm labour? 2
- The uterus expanding quickly
- LGA
What are two ways to lower polyhydramnios?
- Amniocentesis
- Indomethacin
Amniocentesis is performed until the fluid is at what level?
<8
Complications from amniocentesis is what? 3
- PROM
- Preterm delivery
- Infection
What does indomethacin do? How is it administered?
- Prostaglandin inhibitor that decreases fetal urine output
- Administered to mother
What are complications of indomethacin?
Complications = premature closure of ductus arteriosus
When can indomethacin be used?
Early pregnancy
When would we have oligiohydramnios? (measurements)
- AFI is <5cm
- When the largest pocket is <2x2cm
When do we calculate oligohydramnios? How is it calculated?
- 5 1/2 - 9 weeks
- MSD(mm) - CRL(mm) < 5mm
MSD - CRL is what diameter in early olgiohydramnios?
<5mm
What are some causes of oligiohydramnios? 7
- PROM
- IUGR
- Renal anomaly
- Post dates
- Abruption
- Twin to twin transfusion
- Idiopathic
What does this demonstrate?
Olgiohydramnios
What might oligiohydramnios cause? 3
- Limb anomalies (club feet(
- Pulmonary hypoplasia
- Restricted growth
What are some major difference between Poly and Oli hydramnios? 2
- Poly has some. Therapies that can assist, Oli only has one therapy that might help (bed rest)
- Oli- The early it is identified the more severe the affect is on the fetal lungs. Limb and muscle development is also impaired
