Module 5 B Flashcards
What is the difference between fetal movement counting and fetal movement awareness?
What is the evidence for each
How should clinicians instruct patients if they choose to encourage formal fetal movement counting?
How should clinicians instruct patient about fetal movement awareness
Formal fetal movement counting has not been shown to decrease intrauterine fetal death and intrauterine fetal death is often preceded by decreased fetal movement, perceptible by the mother.
Tell patients that it is not normal for fetuses to move less near term but it is common for the character of the movements to change.
A fetus near term who is crowded should still move the same absolute number of times as before but the movements might become nudges and swishes, rather than big kicks.
What is the normal range of fundal height in relation to gestational age in the third trimester
A fundal height in centimeters generally corresponds with the weeks of gestational age with a margin of difference of +/- 2 cm
ie…28 week gestation, fundal heights of 26-30 cm would be in the normal range.
What are the factors in the third trimester that can affect fundal height assessments
- Fetuses have a wider range of normal size, compared with the relatively uniform size of early-gestation fetuses
- Amniotic fluid volume and fetal presentation, can affect fundal height.
- Some fetuses drop into the pelvis in the last weeks of pregnancy, a process known as lightening, and that can cause the fundal height to decrease even as the fetus continue to grow normally.
What should a clinician include in a response to a third trimester patient who asks how big their baby is
What are other clinical indicators of fetal presentation, aside from leopold’s maneuvers
- if the majority of the kicks felt near the fundus, a fetus may be in the cephalic presentation
if heart tones are heard more clearly below the maternal umbilicus rather than toward the fundus…could by in cephalic presentation
Ask patient if they felt any large, somersault feeling movement lately
What are the normal range for fetal heart rate in the third trimester
110-160 BPM
Why and how will you differentiate maternal from fetal heart rates
Pregnancy can result in a rise in maternal heart rate and mature fetuses can have a lower baseline…
ie overlapping 110
To differentiate you can listen to the fetal heart rate with the Doppler and palpate the maternal radial pulse to ensure they are beating at different times/rates.
How is a non stress test conducted?
Pregnant person having an external electronic fetal heart rate monitor applied to their abdomen to record the fetal heart rate.
How will you interpret a non stress test
Two accelerations of at least 15 bpm above the fetal heart rate baseline, lasting at least 15 seconds each (for fetuses at or beyond 32 weeks )
Two accelerations of at least 10 bpm above the fetal heart rate baseline, lasting at least 10 seconds each (for fetuses less then 32 weeks)
What is the follow-up for a nonstress test that is not reactive for 20 minutes
Can consider extending the NST up to a total of 40 minutes or using a vibroacoustic stimulator to encourage the fetus to move/wakeup
what is the follow-up for nonstress test that is not reactive for 40 minutes
Biophysical profile
Why do we assess amniotic fluid volume?
Decreased perfusion to the fetal kidneys can result in decreased fetal urine output
Amniotic fluid is in large part, composed of fetal urine so the volume of amniotic fluid can give us insights into fetal well-being
What are the ways we assess amniotic fluid volume
In terms of one or more pockets of fluid or as an amniotic fluid index (AFI)
AFI is calculated by adding up the fluid pockets in the four quadrants of the maternal abdomen.
what are normal amniotic fluid volume results
Single deepest pocket vertical depth of 2.1-8cm
Amniotic fluid index of 5-25 cm
What criteria are included in a biophysical profile?
what are the criteria for scoring each
5 components/an NST and 4 realtime u/s based
- nonstress test
- fetal breathing movements
- fetal movement
- fetal tone
- Amniotic fluid volume
Why is a amniotic fluid assessment so crucial as a scoring component in a BPP
its a useful indicator of longer-term placental function
What is a modified BPP
Which outcomes require collaboration or followup
Combination of nonstress test and amniotic fluid
Decreased amniotic fluid necessitates follow up
If the NST is nonreactive, generally, the full BPP is then done
what is a contraction stress test
when is it used
sometimes called Oxytocin challenge test (OCT)…based on the premise tha ta fetus with compromised oxygenation will respond to the additional decrease in oxygenation from contractions with compensatory mechanisms that result in a pattern of late FHR decelerations…
Consists of evaluation a FHR strip for the presence of a pattern of late or repetitive variable decelerations in response to a contraction pattern of three or more contractions in a 10 minute period in which each contraction lasts at least 40 seconds
Used as a precursor to induction
what is Doppler flow ultrasonography
when is it used.
Electronic method to monitor fetus: it evaluates blood flow through specific vessels for indications of compromise
Used during an ultrasound to assess the blood flow through specific fetal and maternal vessels.
Compare more mature fetuses heart rate to younger fetuses
Mature fetuses (those nearing term) have a more developed parasympathetic nervous system and therefore, a generally lower baseline heart rate compared with earlier-gestation fetuses
What are the criteria for Non stress using BPP
Adequate (score 2)….reactive
Inadequate (score 0)…non reactive
What are the criteria for Fetal breathing movements for BPP
Reactive: (2)
1 or more episodes of rhythmic fetal breathing movements of 30 seconds or more within 30 minutes
Inadequate (0)
< 30 seconds of sustained fetal breathing movements within 30 minutes
What are the criteria for fetal movement for BPP
Adequate (2)
3 or more discrete body or limb movements within 30 minutes
Inadequate (0)
< 3 discrete body or limb movements within 30 minutes
What are the criteria for fetal tone for BPP
Adequate (2)
1 or more movements of limb from flexion to extension and back to flexion
Inadequate (0)
slow extension with partial flexion or extension with no flexion or no movement
What are the Amniotic fluid volume
What BPP results are assuring
- 10/10 (score of 2 for all 5 elements)
- 8/10 with normal fluid (score of 2 for amniotic fluid, 2 for all other elements with exception of a single element (this is commonly seen when the NST is non-reactive but all other elements earn a score of 2)
- 8/8 without NST (ijf the NST is omitted which can be done in some situations)
What BPP scores require additional/collaborative management
Any BPP in which the amniotic fluid is abnormal
6/10 with normal fluid (score of 2 amniotic fluid but 2 other elements are inadequate)…This is commonly seen when the NST is non-reactive and the fetus does not fully meet the gross movement or tone requirement
4/10 or less
