Antepartum Fetal Testing Flashcards
The most common reasons for fetal testing are
decreased fetal movements, diabetes, post dates, chronic hypertension, and IUGR.
This test assesses the frequency of fetal movements using an external fetal heart rate (FHR) monitoring device to detect the presence or absence of accelerations.
NONSTRESS TEST (NST)
Criteria for NST
<32 weeks, the increase should be ≥10 beats/min lasting ≥10 s
• >32 weeks, the increase should be ≥15 beats/min lasting ≥15 s
Reactive NST requires _______
the presence of 2 accelerations in a 20-min window of time meeting the above criteria.
This is reassuring and highly predictive for fetal well-being
Fetal death rate for reactive NST
Fetal death rate is only 3 per 1,000 in the next week
_____percent of nonreactive NSTs are false positives (meaning the fetus is not hypoxemic).
Eighty
Nonhypoxemic causes of non-reactive NST include
fetal sleep, prematurity, drug effects, and CNS anomalies.
Mx of non-reactive NST
fetal vibroacoustic stimulation to see whether this results in reactivity
If the NST is persistently nonreactive, perform _______
a biophysical profile
The 4-quadrant amniotic fluid index test assesses in centimeters the______
deepest single vertical amniotic fluid pocket in each of the 4 quadrants of the uterus
Interpretation of AFI
<5 cm—oligohydramnios
5–8 cm—borderline
9–25 cm—normal
>25 cm—polyhydramnios
Components of BPP
NST, amniotic fluid volume, fetal gross body movements, fetal extremity tone, and fetal breathing movements
BPP Score 8-10 interpretation
Highly reassuring of fetal well-being.
Management is to repeat the
test weekly or as indicated. Fetal death rate is only 1 per 1,000 in the next week.
BPP Score 4-6 interpretation
Worrisome. Management is delivery if the fetus is >36 weeks or repeat
the biophysical profile in 12–24 h if <36 weeks. An alternative is to perform a CST
BPP Score 0-2 interpretation
Score of 0 or 2—highly predictive of fetal hypoxia with low probability of false positive.
Management is prompt delivery regardless of gestational age.
A modified BPP includes only the _______ and ______Its predictive value is
almost as high as a complete BPP
NST and amniotic fluid volume.
All EFM tracings should be evaluated for the ______ and ______
nonstress test (NST) and the contraction stress test (CST).
If 3 or more uterine contractions (UCs) are present in 10 minutes, the ______components can be assessed as negative or positive.
CST
This test assesses the ability of the fetus to tolerate transitory decreases in intervillous blood flow that occur with uterine contractions
CONTRACTION STRESS TEST (CST
The most common indication for CST is a ______
BPP of 4 or 6.
Negative CST requires ______
requires absence of any late decelerations with contractions.
This is reassuring and highly reassuring for fetal well-being.
Mx of negative CST
Management is to repeat the CST
weekly. Fetal death rate is only 1 per 1,000 in the next week.
Positive CST is worrisome. This requires ________
the presence of late decelerations associated with at least 50% of contractions
CST should not be performed whenever ________
contractions would be hazardous to the mother or fetus
