Antepartum Assessment

Question 1

__ fetal movements in up to 2 hours is considered normal

Answer 1

10 fetal movements

Question 2

t/f normal fetal heart rate baseline and variability means an intact sympathetic nervous system

Answer 2

false, INTACT AUTONOMIC NERVOUS SYSTEM

Question 3

components of the fhr tracing

Answer 3

baseline fetal heart rate
variability
accelerations
decelerations

Question 4

how to take baseline fetal heart rate

Answer 4

identify 2 min segment without periods of marked FHR variability, periodic or episodic changes, and segments of baseline that differ by more than 25 beats

round to the nearest 5 bpm increment

Question 5

fetal heart rates

Answer 5

normal 110-160 bpm
tachy >160
brady <110

Question 6

causes of bradycardia in baseline fetal heart rate

Answer 6

normal variation
bradycardia after deceleration
- hypoxia (abruptio placenta, amniotic fluid embolism)
- decreased umbilical blood flow (cord prolapse or uterine rupture)
- dec uterine blood flow (severe maternal hpn)

Question 7

causes of tachycardia in baseline fetal heart rate

Answer 7

maternal and fetal infection
second stage of labor
drugs

Question 8

types of baseline fhr variability

Answer 8

moderate 5-25 bpm
marked >25 bpm
minimal <5 bpm
absent/undetectable

Question 9

cause of decreased fhr variability

Answer 9

hypoxia/acidosis (+ dec fhr)
fetal sleep cycles (do vibroacoustic stimulation)
congenital anomalies
extreme prematurity
fetal tachycardia
preexisting neuro abnormalities
medications (magnesium sulfate)

Question 10

hypothesis for nonstress test

Answer 10

hr of fetus who is not acidotic as a result of hypoxia or neurological depression will temporarily accelerate in response to fetal movement

Question 11

what is a reactive nst

Answer 11

at least 2 accelerations within a 20 min window

Question 12

back up test for a nonreactive nst

Answer 12

vibroacoustic stimulation test: loud external sound can provoke fhr acceleration

Question 13

test that examines the fetal heart rate characteristics in response to uterine contractions

Answer 13

contraction stress test

Question 14

t/f the hypoxic fetus who has inadequate oxygen reserves cannot tolerate uterine contractions and develops late decelerations

Answer 14

true

Question 15

contraindications for uterine stress test

Answer 15

• premature rupture of membranes
• previous classical cs
• placenta previa
• cervical incompetence
• hx of premature labor
• multiple gestation

Question 16

characteristics of early deceleration

Answer 16

• symmetrical gradual decrease and return
• nadir deceleration is same time as peak contraction
• caused by head compression during second stage of labor

Question 17

characteristics of late deceleration

Answer 17

• symmetrical gradual decrease
• nadir deceleration is AFTER peak contraction
• caused by uteroplacental insufficiency

Question 18

what is a positive cst

Answer 18

late decelerations following > 50% of contractions

Question 19

what are equivocal-suspicious results of cst

Answer 19

intermittent late decelerations or significant variable decelerations

Question 20

what are equivocal-hyperstimulatory results of cst

Answer 20

decelerations in the presence of contractions occurring more frequently than every 2 min or more than 90 secs

Question 21

what are unsatisfactory results of cst

Answer 21

<3 contractions in 10 mins

Question 22

characteristics of variable deceleration

Answer 22

apparent abrupt decrease in fhr >/= 15 bpm, >15 sec but < 2 min

Question 23

causes of variable deceleration

Answer 23

oligohydramnios
fetal head descent
cord prolapse

Question 24

what are done during sonographic assessment

Answer 24

fetal biometry
biophysical score
doppler velocimetry

Question 25

small for gestation age vs iugr

Answer 25

sga: fetal size and weight at birth are less than expected regardless of cause (<10th percentile) iugr: abnormal growth velocity pattern due to placental insufficiency

Question 26

components of biophysical profile scoring

Answer 26

slide 43

Question 27

interpretation of bps

Answer 27

slide 44 normal afv = ok dec afv = deliver

Question 28

when does placental blood flow increase

Answer 28

20th week REVIEW SLIDE 47

Question 29

absent vs reversed edf

Answer 29

absent: at least 60% of placental vessels are obliterated reversed: at least 70% of placental vessels are diseased (fetal distress in 3-5 days)

Question 30

t/f late adaptation in the fetal circulation includes preferential shunting for blood flow to brain, heart, and adrenals (brain sparing reflex)

Answer 30

false, EARLY ADAPTATION

Question 31

review slide 51

Answer 31

ok

Question 32

maternal indications for antepartum fetal surveillance

Answer 32

dm, hpn, sle, ckd, aps hemoglobinopathies cyanotic heart disease hyperthyroidism

Question 33

pregnancy related indications for antepartum fetal surveillance

Answer 33

``` preeclampsia decreased fetal movement gestational diabetes oligohydramnios fetal growth restriction postterm previous detal demise monochorionic twin ```

Question 34

when should atepartum fetal surveillance be started?

Answer 34

32 weeks aog | for multiple/high risk: 26 wks or aog when delivery is considered

Question 35

what is the recommended frequency of antepartum fetal surveillance

Answer 35

if indication is not persistent, no need to repeat if indication persists or high risk, test periodically

Question 36

first principle of fhr interpretation

Answer 36

all clinically significant decelerations reflect interruption of the pathway of oxygen transfer from the environment to the fetus at one or more points.

Question 37

t/f sustained or recurrent interruption of oxygen transfer, reflected in the FHR tracing as deceleration, has the potential to result in hypoxic neurologic injury.

Answer 37

true

Question 38

steps that result to metabolic acidemia

Answer 38

hypoxemia -> hypoxia -> metabolic acidosis -> metabolic acidemia

Question 39

second principle of fhr interpretation

Answer 39

acute intrapartum interruption of fetal oxygenation does not result in neurologic injury in the absence of significant metabolic acidemia. Significant metabolic acidemia is defined as an umbilical artery pH of <7 and base deficit of >/= 12mmol/L

Question 40

third principle of fhr interpretation

Answer 40

moderate variability and /or accelerations reliably predict the absence of fetal metabolic acidemia at the time they are observed.

Question 41

characteristics for category 1 fhr

Answer 41

``` 110-160 bpm moderate variability - late and variable decelerations +/- early decelerations +/- accelerations ```

Question 42

characteristics of category 3 fhr

Answer 42

absent fhr variability with: - recurrent late d - recurrent variable d - bradycardia sinusoidal pattern

Question 43

sinusoidal pattern

Answer 43

usually seen in fetal anemia and intraamniotic infection

Question 44

characteristics of category 2 fhr

Answer 44

anything else requires evaluation and surveillance

Question 45

what to do when pt is in category 2

Answer 45

- discontinue oxytocin - cervical exam: cord prolapse, rapid cervical dilatation, descent of fetal head - change maternal position to recumbent position - monitor for hypotension - asses for uterine hyperstimulation

Question 46

t/f if there is no efm, intermittent auscultation can be done every 5-15 mins

Answer 46

true

Question 47

other intrapartum assessment techniques

Answer 47

fetal scalp blood sampling (deliver if <7.2 ph) fetal scalp stimulation (no acceleration if + acidosis) fetal pulse oximetry (cs if <30% between 2 contractions)

Question 48

t/f There is an approximately one-hour window from the start of the FHR pattern containing minimal baseline variability and late or prolonged decelerations

Answer 48

true

Question 49

if vaginal delivery is not likely before the onset of metabolic acidemia ___ must be done

Answer 49

operative delivery