CHAPTER 15: AMNIOTIC FLUID

Question 1

The constituents that are present in the fluid provide information about the metabolic processes taking place during—as well as the progress of—fetal maturation

Answer 1

Amniotic fluid

Question 2

a membranous sac that surrounds the fetus where amniotic fluid is present

Answer 2

amnion

Question 3

Cells composing the amnion

Answer 3

cuboidal cells

Question 4

Functions of amniotic fluid (4)

Answer 4

1) Protective cushion for the fetus
2) Allow fetal movement
3) Stabilize temperature
4) Permit proper lung development

Question 5

A volume of amniotic fluid greater than 1200 mL is called

Answer 5

Polyhydramnios

Question 6

The volume of amniotic fluid less than 800 mL is termed

Answer 6

Oligohyramnios

Question 7

During the 1st trimester, 35 mL of amniotic fluid is derived from _____________.

Answer 7

maternal circulation

Question 8

Major contributor to the amniotic fluid volume after the 1st trimester.

Answer 8

Fetal urine

Question 9

Indication of fetal distress and often associated with neural tube disorders.

Answer 9

Failure of the fetus to begin swallowing urine which results in excessive accumulation of amniotic fluid (polyhydramnios)

Question 10

May be associated with
> congenital malformations
> premature rupture of amniotic membranes
> umbilical cord compression

resulting in decelerated heart rate and fetal death.

Answer 10

Oligohydramnios

Question 11

The ultimate source of amniotic fluid water and solutes

Answer 11

placenta

Question 12

Allow fetal cerebrospinal fluid to enter the amniotic fluid directly.

Answer 12

Neural Tube Defects

Question 13

Two biochemical makers tested to detect Neural Tube Defects (NTDs)

Answer 13

Alpha-fetoprotein (screening)
Acetylcholinesterase (confirmatory)

Question 14

Used to determine fetal age

Answer 14

amniotic fluid creatinine (>2.0mg/dL = 36 weeks/9months)

Question 15

Differentiates amniotic fluid and maternal urine

Answer 15

Chemical analysis of creatinine, urea, glucose, and protein

*crea and urea - lower in amniotic, high in urine

Question 16

Can differentiate amniotic fluid from urine and other body fluids used to evaluate premature rupture of the membranes

Answer 16

Fern test

Question 17

Specimen for fern test

Answer 17

Vaginal fluid

Question 18

Positive screen for amniotic fluid in fern test, where fern-like crystals appear are due to what content/s?

Answer 18

protein and sodium chloride

Question 19

Amniotic fluid pH

Answer 19

7.1 to 7.3

Question 20

A screening test used to determine the presence of amniotic fluid in vaginal secretions.

Answer 20

nitrazine test

Question 21

A blue-colored strip indicating a pH greater than 6.0 in a nitrazine test suggests …

Answer 21

membranes have ruptured

Question 22

Referred to as placental protein

Answer 22

Insulin-like growth factor binding protein -1 (IGFBP-1)

Question 23

Recommended for cases of NTDs when screening blood tests, such as the maternal serum AFP test, are abnormal or to detect genetic disorders or to evaluate the health of the fetus

Answer 23

Amniocentesis

Question 24

Note:

Amniocentensis - after 14th week of gestation

Fluid chromosome analysis - 16 weeks

Intrauterine growth retardation - end of 2nd trimester

Fetal distress and matury - Later in 3rd trimester

Question 25

Max. volume of amniotic fluid collected in sterile syringes

Answer 25

30 mL (First 2/3mL = discarded)

Question 26

Transport medium for fetal lung maturity test fluid

Answer 26

ice

Question 27

Used to determine the source of the blood (maternal or fetal) for fetal hemoglobin

Answer 27

Kleihauer-Betke Test

Question 28

Gives the fluid a yellow color and is indicative of red blood cell destruction resulting from HDFN.

Answer 28

bilirubin

Question 29

Defined as a newborn’s first bowel
movement, a dark green, mucus-like material. It may be present in the amniotic fluid as a result of fetal distress.

Answer 29

Meconium

Question 30

A very dark red-brown fluid is associated with

Answer 30

fetal death

Question 31

Measures amniotic fluid bilirubin

Answer 31

spectriophotonetric analysis using serial dilution

Question 32

Most common birth defects in the United States

Answer 32

Neural Tube Defects (NTDs)

Question 33

Most frequent complication of early delivery and is the seventh most common cause of morbidity and mortality in the premature infant.

Answer 33

Fetal Lung Maturity

Question 34

Keeps the alveoli from collapsing by decreasing surface tension and allows them to inflate with air more easily

Answer 34

Surfactant

Question 35

Reference method to which tests of FLM are compared

Answer 35

Lecithin-sphingomyelin Ratio

Question 36

Primary component of surfactant that make up the alveolar lining and account for alveolar stability

Answer 36

Lecithin

Question 37

Indication when the L/S ratio reaches 2.0

Answer 37

Safe preterm delivery

Question 38

A mechanical test used to measure the individuall lung-surface lipid concentrations

Answer 38

Foam or Shake Test

Question 39

Composition of surfactant

Answer 39

90% phospholipids
10% protein

*packaged into layered storage granules called lamellar bodies

Question 40

They are secreted by the type II pneumocytes of the fetal lung at about 24 weeks of gestation and are absorbed into the alveolar spaces to provide surfactant

Answer 40

Lamellar bodies

Question 41

True or False.

Amniotic fluid specimens containing whole blood, meconium, and mucus should not be used

Answer 41

True