Amniotic Fluid Flashcards

1
Q

What functions do the amniotic fluid provide for the baby?

A

(1) Protection

(2) Biochemical Processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What two anatomical units provide the formation of amniotic fluid?

A

Amnion and Placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

(T/F) Amniotic fluid is similar to plasma early in the pregnancy?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What two main actions occur when a fetus is swallowing and urinating?

A

(1) Intestinal Absorption

(2) Capillary Exchange

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What occurs within the amniotic fluid when the fetus swallows?

A

It removes electrolytes and water from the fluid.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What occurs within the amniotic fluid when the fetus urinates?

A

Outputs urea, creatinine, and uric acid which is exchanged with the maternal plasma in a dynamic process.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the procedure called for the collection of amniotic fluid?

A

Amniocentesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

At what age is it a requirement for a mother to receive an amniocentesis?

A

> = 35 years old

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

A pregnant mother has a chromosomal abnormality, at what age of the fetus should amniotic fluid be collected to check for fetus abnormalities?

A

14-18 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

A pregnant mother has a first child with chromosomal abnormalities, at what age of the fetus should the amniotic fluid be collected to check for chromosomal abnormalities within the fetus?

A

14-18 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

A mother finds out she is pregnant, but she has a history of a metabolic disorder, at what age of the fetus should amniotic fluid be collected to ensure no additional stress is being brought the baby?

A

14-18 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

A mother if found to have elevated maternal alpha-fetoprotein in her most recent lab work. At what age of the fetus should amniotic fluid be collected to ensure the baby isn’t receiving any addition stress? What could happen to the baby?

A

14-18 weeks; suspected neural tube defect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

At what age of the fetus should amniotic fluid be collected to assess fetal distress due to blood group incompatibility or infection?

A

20-42 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

At what age of the fetus should amniotic fluid be collected for the assessment of fetal lung maturity?

A

20-42 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How much fluid can be received from one amniocentesis?

A

15-30 mL of amniotic fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What type of tube should the amniotic fluid be place in?

A

Sterile, plastic, amber colored container

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

If you were to use a glass tube instead of a plastic tube?

A

Fetal cells can stick to glass and cause an altered result.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Why is an amber colored tube important?

A

Light can cause bilirubin to break down a cause a false decrease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

For cell cultures, chromosomal studies, and microbial/viral cultures, at what temperature should you place the amniotic fluid sample?

A

Room temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

For fetal lung maturity testing, at what temperature should you store the amniotic fluid sample?

A

Refrigerated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What type of testing would require centrifugation at high speeds?

A

Spectrophotometric Assays (bilirubin)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What type of testing would require centrifugation at low speeds?

A

Recovery of fetal cells (cell cultures)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How would you differentiate between amniotic fluid and urine for glucose testing?

A

Amniotic fluid contains glucose; urine (usually does not)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How would you differentiate between amniotic fluid and urine for protein testing?

A

Amniotic fluid typically has protein (2-8 g/dL); urine (usually) contains no protein.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How would you differentiate between amniotic fluid and urine for creatinine testing?

A

Amniotic fluid has similar creatinine levels to plasma until ~37 weeks; urine has creatinine levels 50-100x greater than plasma.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How would you differentiate between amniotic fluid and urine for ferning testing?

A

Amniotic fluid has ferning persent; urine has ferning absent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the normal color of amniotic fluid?

A

Colorless to pale yellow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What could be the cause of amber/yellow amniotic fluid?

A

Bilirubin

29
Q

What could be the cause of green amniotic fluid?

A

Meconium

30
Q

What could be the cause of red amniotic fluid?

A

Blood contamination

31
Q

What is meconium?

A

A gelatinous/mucoid type material that is formed within the fetal intestines (baby’s first poop).

32
Q

What is the turbidity of amniotic fluid early in pregnancy?

A

Not very turbid

33
Q

What is the turbidity of amniotic fluid as pregnancy progresses?

A

Becomes more turbid from fetal cells, hair, vernix, etc.

34
Q

What does fetal lung maturity testing help indicate?

A

Respiratory distress after 40 weeks.

35
Q

What is the minimum age of the fetus a doctor can order FLM testing and still provide an accurate result?

A

After 32 weeks; before will always indicate premature lung development.

36
Q

(T/F) FLM testing will produce results that will indicate a lack of surfactant.

A

True

37
Q

What is surfactant?

A

(1) Alters surface tension of alveoli (expiration)

2) Reduces the amount of pressure to reopen the alveoli (inspiration

38
Q

For Lecithin/Sphingomyelin (L/S) Ratio testing, what is lecithin?

A

Surfactant

39
Q

For Lecithin/Sphingomyelin (L/S) Ratio testing, what is sphingomyelin?

A

Phospholipid

40
Q

At what age does the Lecithin/Sphingomyelin (L/S) Ratio begin to increase?

A

33 weeks

41
Q

In terms of Lecithin/Sphingomyelin (L/S) Ratio, what occurs between 34 and 36 weeks?

A

Level of lecithin ↑, sphingomyelin → or ↓

42
Q

For L/S Ratio, what does a result of >2.0 indicate?

A

Indicates fetal lung maturity

43
Q

For L/S Ratio, what does <2.0 indicate?

A

Indicates immature lungs

44
Q

For L/S Ratio testing, how can blood affect the results?

A

Blood can cause a false decrease.

45
Q

For L/S Ratio testing, if a sample has blood contamination, and you receive a result of <2.0, how should you proceed?

A

Cancel the test; cannot use result (inaccurate)

46
Q

For L/S Ratio testing, if a sample has blood contamination, and you receive a result of >2.0, how should you proceed?

A

Okay to use result; add comment to report.

47
Q

How does meconium contaminated specimens affect the L/S Ratio result?

A

Should not be used at all; causes a false increase.

48
Q

At what age is phosphatidylglycerol (PG) detected?

A

35 weeks gestation

49
Q

What are some advantages of phosphatidylglycerol (PG) testing?

A

Can be faster (TLC vs. Agglutination) and it’s not affected by blood or meconium

50
Q

What are some disadvantages of phosphatidylglycerol (PG) testing?

A

High false negative rate

51
Q

At what age is Lamellar body counts tested?

A

20-24 weeks

52
Q

What happens to the results if there is blood contamination within a Lamellar body count?

A

False increased from platelets; false decreased with clot

53
Q

For Lamellar body counts, what is considered mature FLM?

A

> 50,000/uL

54
Q

For Lamellar body counts, what is considered immature FLM?

A

<15,000/uL

55
Q

What is another name for the Foam Stability Index (FSI)?

A

Shake Test

56
Q

What do you add to Foam Stability Index (FSI) prior to shaking?

A

Ethanol

57
Q

What ratio are you testing during a Foam Stability Index (FSI)?

A

Ethanol:Amniotic Fluid Ratios

58
Q

What ratio is indicative of lung maturity for the Foam Stability Index (FSI)?

A

> 0.47

59
Q

What is a disadvantage of the Foam Stability Index (FSI)?

A

Meconium or bloody samples can cause a false increase.

60
Q

The amount of bilirubin present is ___ related to the ___ that is happening within the fetus.

A

The amount of bilirubin present is directly related to the hemolysis that is happening within the fetus.

60
Q

The amount of bilirubin present is ___ related to the ___ that is happening within the fetus.

A

The amount of bilirubin present is directly related to the hemolysis that is happening within the fetus.

61
Q

What testing method is done for amniotic fluid bilirubin determination?

A

Spectrophotometry

62
Q

How would blood affect the bilirubin result?

A

Oxyhemoglobin peak absorbance between 410-540nm.

63
Q

How would light affect the bilirubin result?

A

Falsely decrease bilirubin levels (bilirubin sensitive to light)

64
Q

How would meconium affect the bilirubin result?

A

Absorbance between 350-400 nm; falsely low result.

65
Q

What does each Zone indicate?

A

Zone I - minimally effected
Zone II - hemolysis occurring
Zone III - severe hemolysis

66
Q

If an AmniSure test is positive, what is that indicative of?

A

Premature rupture of membranes (PROM) has occured.

67
Q

What is an advantage of AmniSure testing?

A

Can work with contaminated samples.

68
Q

What is AmniSure testing for?

A

Placental alpha-microglobulin-1 (PAMG-1)