FETAL ASSESMENT Flashcards
Techniques employed today to forecast fetal wellbeing focus on fetal biophysical indings that include heart rate,
movement, breathing, and amnionic luid production. These
Findings aid __________ to prevent fetal death
and avoid unnecessary interventions.
antepartum fetal surveillance
Indeed, ___________ -a true negative test-for
most of the tests described are 99.8 percent or higher.
negative-predictive values
In
contrast, estimates of the ___________ -a true
positive test-for abnormal test results are low and range
between 10 and 40 percent.
positive-predictive values
Passive unstimulated fetal activity commences as early as
_________ and becomes more sophisticated and coordinated by the end of pregnancy
7 weeks’ gestation
Indeed, beyond __________, fetal body movements are
never absent for periods exceeding 13 minutes
8 menstrual weeks
Between _____________, general body movements
become organized, and the fetus starts to show rest-activity
cycles
20 and 30 weeks’ gestation
Fetal movement maturation continues
until approximately ________, when behavioral states are established in most normal fetuses
36 weeks
_______ is a quiescent state-quiet sleep-with a narrow
oscillatory bandwidth of the fetal heart rate
State 1F
_______ includes frequent gross body movements, continuous eye movements, and wider oscillation of the fetal heart rate.
State 2F
This state is analogous to rapid eye movement (EM)
or active sleep in the neonate.
State 2F
________ includes continuous eye movements in the absence
of body movements and no heart rate accelerations
State 3F
_______ is one of vigorous body movement with continuous
eye movements and heart rate accelerations. his state corresponds to the awake state in newborn
State 4F
Fetuses spend most of their time in ______ and _______.
states IF and 2F
At _______, 75 percent of time is spent in these two
states (State 1F and 2F).
38 weeks
These behavioral states-particularly IF and 2F, which correspond to _______ and ______ -have been used to develop
an increasingly sophisticated understanding of fetal behavior
quiet sleep and active sleep
In a
study of fetal urine production, bladder volumes increased during
___________.
state IF quiet sleep
During ______, the fetal heart rate
baseline bandwidth increased appreciably, and bladder volume
was significantly diminished due to decreased urine production
and infrequent fetal voiding.
State 2F
An important determinant of fetal activity appears to be
__________, which are independent of maternal ones.
sleep-awake cycles
Fetal sleep cyclicity varies from approximately _________ to
as much as _________
20 minutes
75 minutes
In one study, the mean length of the
quiet or inactive state for term fetuses was _________.
23 minutes
___________ is another
important determinant of fetal activity
Amnionic fluid volume
Sadovsky and coworkers ( 1 979b) classified fetal movements into three categories according to both maternal perceptions and independent recordings using ________.
piezoelectric
sensors
_____, _____ and ________ were described,
and their relative contributions to total weekly movements
throughout the last half of pregnancy were quantified.
Weak, strong, and rolling movements
________ may be a harbinger of impending fetal
death
Diminished fetal activity
To quantfiy fetal movement, clinical
methods include use of:
uterine contraction tocodynamometer
visualization with sonography
maternal subjective
perceptions.
Fetal motions lasting more than _________ were more likely to be identified than shorter episodes
20 seconds
Commonly, women may present in the ________ complaining of subjectively
reduced fetal movement
third trimester
_________ were employed if sonographic scans for
fetal growth or Doppler velocimetry were abnormal.
Fetal heart
rate monitoring tests
Another interesting feature of fetal respiration was _______________.
paradoxical chest wall movement
One interpretation of the paradoxical respiratory motion might be ________ to clear amnionic fluid debris.
coughing
During inspiration, the chest wall paradoxically ______ and the abdomen ______.
collapses
protrudes
During expiration, the chest wall _______
expands
The first are gasps or sighs which occurred at a frequency of ____ per minute.
1 to 4
The second ___________, occurred at rates up to ______ cycles per minute.
Irregular bursts of breathing
240
These rapid respiratory movements
were associated with rapid eye movement.
Irregular bursts of breathing
They suggested that
fetal respiratory rate declined in conjunction with increased
respiratory volume at _________ and coincidental with
lung maturation.
33 to 36 weeks
Many investigators have examined fetal breathing movements using _________ to determine whether chest wall movements might reflect fetal health.
sonography
Several variables in addition
to hypoxia were found to afect fetal respiratory movements.
These included: -during which it is normal
for respiration to cease.
hypoglycemia sound stimuli cigarette smoking amniocentesis impending preterm labor gestational age fetal heart rate labor (normal for respiration to cease)
Because fetal breathing movements are ______, interpretation of fetal health when respirations are absent may be tenuous
episodic
Total
absence of breathing was observed in some of these normal fetuses
for up to ________, indicating that fetal evaluation to diagnose
absent respiratory motion may require long periods of observation
122 minutes
Most clinical
applications have included assessment of other fetal biophysical indices, such as __________.
heart rate
Fetal breathing has become a component of the __________.
biophysical profile
Contractions
also may produce a pattern of variable decelerations as a result of cord compression, suggesting __________, which is often a
concomitant of placental insufficiency.
oligohydramnios
Ray and colleagues ( 1972) used this concept in 66 complicated pregnancies and developed the oxytocin challenge test, which
was later called the ___________.
contraction stress test
_________ is
used to stimulate contractions
Intravenous oxytocin
The criterion for a positive test result that is an abnormal result is ____________.
uniform repetitive late fetal heart rate decelarations
A major disadvantage is that the average contraction
stress test requires _________ to complete.
90 minutes
If at least _____ spontaneous contractions of _________ are
present in ________, no uterine stimulation is necessary.
three
40 seconds or longer
10 minutes
Contractions are induced with either _________ or ________
if there are fewer than three in 10 minutes.
oxytocin or nipple stimulation
For oxytocin use, a
dilute intravenous infusion is initiated at a rate of _______ and
doubled every _________ until a satisfactory contraction pattern is
established
0.5 mU/min
20 minutes
____________ to induce uterine contractions is usually successful for contraction stress testing.
Nipple stimulation
This
__________ ideally will induce a pattern of
three contractions per 10 minutes
2-minute nipple stimulation
If not, after a ________
interval, she is instructed to retry nipple stimulation to achieve
the desired pattern. I
5-minute
Freeman (1975) and Lee and colleagues (1975) introduced the
_________ to describe fetal heart rate acceleration in response to
fetal movement as a sign of fetal health.
nonstress test
This test involved the use
of Doppler-detected fetal heart rate acceleration coincident with
fetal movements perceived by the mother.
nonstress test
no late or significant variable decelerations
Negative
late decelerations following 50% or more of contractions (even if the contraction frequency is fewer than three in
10 minutes)
Positive
Intermittent late decelerations or significant variable decelerations
Equivocal-suspicious
fetal heart rate decelerations that occur in the presence of contractions more frequent than
every 2 minutes or lasting longer than 90 seconds
Equivocal-hyperstimulatory
fewer than three contractions in 10 minutes or an uninterpretable tracing
Unsatisfactory
he nonstress test was easier to perform, and normal results
were used to further discriminate __________.
false-positive contraction stress
tests
the nonstress test is primarily a test of ________ and it differs from the contraction stress test, which is
considered a test of _________
fetal condition
uteroplacental function
Currently, ________ is the most widely used primary testing method for assessment of fetal well-being.
nonstress testing
__________ is also under the control of the autonomic nervous system.
Beat-to-beat variability
Consequently, pathological loss of fetal heart rate acceleration
may be seen in conjunction with significantly ______ beat-to-beat variability
decreased
Loss of such reactivity,
however, is most commonly associated with ________. It also
may be caused by __________ from medications or __________.
sleep cycles
central depression
cigarette smoking
The nonstress test is based on the hypothesis that the heart
rate of a fetus that is not acidemic as a result of hypoxia or
neurological depression will temporarily accelerate in response
to _________.
fetal movement
Fetal movements during testing are identified by ___________ and recorded.
Maternal perception
