Fetal Monitoring

Question 1

causes of adverse fetal neonatal outcomes

Answer 1

antepartum complications
suboptimal uterine perfusion
placental dysfunction
intrapartum events

Question 2

why is fetal heart monitoring so important?

Answer 2

early recognition of changes in FHR can serve as a warning to physician to intervene and prevent irreversible brain injury or death

Question 3

external monitoring for uncomplicated pregnancy

Answer 3

q30 minutes in active phase of stage 1

q15 minutes in stage 2

Question 4

external monitoring for complicated preganancy

Answer 4

q15 minutes in active phase of stage 1

q5 minutes in stage 2

Question 5

what provides the most accurate FHR tracings?

Answer 5

internal monitoring

Question 6

components of external fetal monitoring

Answer 6

doppler ultrasound overlying the fetal heart

pressure-sensitive tocodynamometer - records contractions

Question 7

components of internal fetal monitoring

Answer 7

fetal scalp electrode

intrauterine pressure catheter

Question 8

what happens to placental exchange of gases during contraction?

Answer 8

temporarily stops due to:
compression of uterine myometrial vessels
compression of umbilical cord
compression of fetal head

Question 9

how long can a fetus last without oxygen?

Answer 9

1-2 minutes due to fetal oxygen reserve

Question 10

what is the result of severe fetal hypoxia

Answer 10

anaerobic metabolism resulting in accumulation of pyruvic and lactic acid = acidosis

Question 11

what is a normal uterine contraction?

Answer 11

5 contractions or less in 10 minutes averaged over a 30 minute window

Question 12

what is uterine tachysystole?

Answer 12

> 5 contractions in 10 minutes averaged over a 30 minute window

presence or absence of associated FHR decelerations

Question 13

baseline FHR

Answer 13

110-160

Question 14

causes of fetal bradycardia (< 100 bpm)

Answer 14

fetal hypoxia (late sign)
obstetric anesthesia
pitocin
maternal hypotension
prolapsed or prolonged compression of umbilical cord
heart block

Question 15

causes of fetal tachycardia ( > 160 bpm)

Answer 15

*fetal infection (chorioamnionitis)* most common!
fetal hypoxia (early sign)
medications 
arrhythmias
prematurity
maternal fever

Question 16

FHR variability

Answer 16

amplitude

decrease may be an indication of fetal distress

Question 17

causes of decreased variability

Answer 17

prematurity
sleep cycle
maternal fever
fetal tachycardia
congenital anomalies
maternal hyperthyroidism
maternal drugs/substances

Question 18

are FHR changes during contractions normal?

Answer 18

yes!

acceleration or deceleration

Question 19

physiological accelerations

Answer 19

an abrupt increase in FHR is a normal and reassuring response

≥ 32 weeks FHR ≥ 15 bpm above baseline for < 2 minutes

< 32 weeks FHR ≥ 10 bpm above baseline for < 2 minutes

Question 20

causes of physiological accelerations

Answer 20

spontaneous fetal movement
scalp stimulation or vibroacoustic stimulation
vaginal exam

Question 21

physiological decelerations

Answer 21

occurs in response to uterine contractions:
head compression
umbilical cord compression

Question 22

late deceleration

Answer 22

caused by uterine placental insufficiency (UPI)

indicates fetal metabolic acidosis and low arterial pH

Question 23

what type of deceleration occurs during pushing?

Answer 23

prolonged decelerations

≥ 2 mins but < 10 mins

Question 24

sinusoidal pattern of FHR

Answer 24

smooth, sine wave-like pattern

seen with fetal anemia

Question 25

category I tracing

Answer 25

baseline 110-160 bpm moderate variability no late or variable decelerations accelerations and early decelerations may be present

Question 26

tx for recurrent variable deceleration

Answer 26

amnioinfusion to reduce cord compression normal saline instillation via transcervical IUPC

Question 27

category II tracing

Answer 27

``` intermittent variable decelerations recurrent variable decelerations minimal or absent variability recurrent late decelerations prolonged decelerations tachy brady tachysystole variable, late or prolonged during pushing ```

Question 28

tx for category II tracing

Answer 28

``` lateral positioning IVF bolus O2 decreased oxytocin modification of pushing efforts ```

Question 29

category III tracing

Answer 29

absent baseline variability

Question 30

tx for category III tracing

Answer 30

scalp stimulation test | if test shows no acceleration, prepare for delivery

Question 31

fetal scalp stimulation

Answer 31

used to determine fetal sleep vs acidosis normal response is acceleration of 15 bpm lasting 15 seconds

Question 32

does FHR monitoring reduce risk of cerebral palsy?

Answer 32

nope