Monitoring the Fetus in Labor

Question 1

Normal FHR

Answer 1

110-160 bpm

Question 2

What are external tocometers useful for?

Answer 2

Measuring frequency of contractions and comparing them to fetal heart tracing to determine the type of contractions that are occurring

Question 3

What is variability?

Answer 3

Moment to moment variation from baseline

Question 4

A FHR deceleration and rate of what would be cause for concern?

Answer 4

deceleration > 2 min with HR > 90 bpm

Question 5

Variability

Answer 5

moment-to-moment variation from the baseline)

Question 6

Absent Variability

Question 7

Minimal variability

Answer 7

3-5 beats per minute of variation

Question 8

Moderate variability

Answer 8

5-25 beats per minute of variation

Question 9

Marked variability

Answer 9

> 25 beats per minute of variation

Question 10

How many cycles of the HR around the baseline should there be?

Answer 10

At least 3-5 cycles per minute of the HR around the baseline

Question 11

Parameters of a reactive tracing

Answer 11

at least 2 accels within 20 minutes that last for at least 15 seconds and go up at least 15 beats higher than the baseline

aka “2 accel of at least 15 bpm over the baseline that last for 15 seconds within 20 minutes”

Question 12

V C
E H
A O
L P

Answer 12

Variable = Cord compression
Early = Head compression
Accel = OK
Late = Poor placental perfusion

Question 13

Early Decelerations: Curve characteristics

Answer 13

Begin/end same time as contractions

D/t increased vagal tone 2⁰ to head compression

Question 14

Variable Decelerations: Curve characteristics

Answer 14

Occur at any time. Drop more precipitously than the others.

D/t Umbilical cord compression (e.g. under shoulder or nuchal cord)

Question 15

Late Decelerations: Curve characteristics

Answer 15

Begin at peak of contraction, and slowly return to baseline after contraction is finished

D/t Uteroplacental insufficiency

Question 16

What does the Fetal Scalp Electrode measure?

Contraindications?

Answer 16

Potentials generated by the depolarization of the fetal heart

Contraindications: hx of maternal hepatitis, HIV, or fetal thrombocytopenia

Question 17

What is Category I FHR?

Answer 17

Normal baseline
Mod variability
No variable or late decels

Question 18

What is Category III FHR?

Answer 18

Abnormal
Absent variability
Recurrent late/variable decels and bradycardia
Sinusoidal pattern (fetal anemia)

Question 19

What is Category II FHR?

Answer 19

Everything else NOT a Category I or III

Question 20

Where is the IUPC placed?

Answer 20

Just past fetal presenting part into the uterine cavity

Question 21

What is the baseline intrauterine pressure?

Answer 21

10-15 mmHg

Question 22

By how much will intrauterine pressure increase during contractions?

Answer 22

Early labor: 20-30 mmHg; 40-60 mmHg as labor progresses

Question 23

What is the Montevideo Unit? What is considered adequate?

Answer 23

increased uterine pressure above baseline X # of contractions in 10 minutes. [200 Montevideo units]

Question 24

What can you do to assess fetal hypoxia and acidemia if a FH tracing is non-reassuring?

Answer 24

Obtain a Fetal Scalp pH

Question 25

Reassuring Fetal Scalp pH?

Answer 25

> 7.25

Question 26

Indeterminate Fetal Scalp pH?

Answer 26

7.20-7.25

Question 27

Nonreassuring Fetal Scalp pH?

Question 28

When obtaining a Fetal Scalp pH, what should you be careful about?

Answer 28

Contamination of sample with amniotic fluid (which is basic)

Question 29

What is a normal Pulse Oximeter reading?

Answer 29

> 30%