Antepartum assessment Flashcards
what are the types of fetal surveillance?
- Antenatal: maternal self-assessment, NST, US, doppler.
- intrapartum: auscultation of fetal heart rate, electrical fetal monitoring, fetal blood scalp sampling
What is the maternal self-assessment of fetal wellbeing?
Kick counting (10movement in 1hr)
What is a normal fetus NST finding?
Normal fetus respond to fetal movement with
- HR >15 Bpm
- for 15 sec
(Acceleration)
What is non-stress test vs stress test?
NST: HR without any external stress (medications, uteine contraction, illness)
How many accelerations is considered normal in a reactive NST?
2 acceleration
BPP is usually taken at which week?
After 28 weeks.
What is the normal profile for BPP
10 (each score is given 2)
What are the component of biophysical profile?
1- fetal breathing movement 2- gross body movement 3- fetal tone 4- amniotic fluid volume 5- NST
What is the normal fetal breathing movement?
within 30 min:
One or more fetal breathing lasting 30 sec
What is the normal gross body movement in BPP
within30 min: 3 or more body\limb
What is the normal fetal tone in BPP
Within 30 min: 1 or more active extension\flexsion - OR - opening\closing of the hand
What is the normal amniotic fluid volume
deepest vertical pocket: Greater than 2cm
When do we proceed with doppler assessment of the umbilical artery?
Decreased fetal fluid, tone, or BPP less than 10
How can we determine blood flood, from which arteries?
1- umbilical artery
2- uterine artery
3- ductus venosus
What is the most problematic cause for fetal hypoxia
Placental insufficency measured by fetal umbilical artery
What does absent diastole mean in doppler assessment of umbilical artery?
Compromised blood flow
What does reversed diastole mean in doppler assessment of umbilical artery?
At risk of fetal death and need to be delivered immediately
What are the causes for compromised blood flow to the fetus?
1- umbilical cord: one artery, vasa previa
2- placenta: infarction, abruptio
3- maternal: HTN, Hypo, anemia, seizure
4- fetal: anemia, infection, twin, IUGR
5- uterine: hyperstimulation, tetanic contraction
What are the chain of events after decreased perfusion to fetus?
Hypoxic acedemia > resp acidosis > met acidosis >encephalopathy > CP
how to auscultate for fetal heart rate intrapartum?
beginning
of 1 contraction to the beginning of other.
Using doppler or stethoscope
What is the duration of listening to fetal heart rate intrapartum?
Every 30 min (1st stage)
Every 15 min (2nd state)
How to measure fetal heart rate in high risk patients?
Using continues electrical fetal heart rate monitoring
What does EFM report?
FHR, MHR, uterine contractions,
How to interpret fetal heart rate?
DR C BRAVADO
- Determine risk
- contraction
- baseline rate
- variability
- acceleration & deceleration
- overall assessment
How to determine the risk?
Patients history, fetal reserve, and labor progression
How to assess the uterine activity pattern?
either by extranal toco or IUPC or palpation
What to assess in uterine activity
1- frequency
2- duration
3- intensity
3- resting tone
How to measure the frequency of contraction in external toco?
From peak to peak
Adquate: in 10 min we have 3 or more
How to measure the duration of contraction in external toco?
Every red line is a minute
How to measure the intensity of contraction in external toco? s
Substracting the peak from the baseline
Adquate: 200 or more
What unit used in IUPC to assess uterine activity?
MVU which is indicative of intensity
IUPC is a
Quantative vs Quallitative
Quantitative
When is IUPC is more useful?
- Obesity
- dysfunctional labor
What is the normal FHR baseline range
110-160
How to measure the baseline heartrate
Any 2 minutes in 10 minutes
That is NOT
1- changes (periodic\episodic)
2- variability
3- segment differ by >25bpm
What is bradycardia in baseline rate
<110 in 2minutes
What are the causes of bradycardia in fetus?
- magnesium sulfate
- prematurity
- fetal heart problem (AV block)
What are the cause of tachycardia?
Chorioamionitis, maternal fever, fetal heart problem
Whay is variability
Fluctuation in baseline heart rate
How to measure variability in heart rate?
Choosing 1 minute of 10 min section
(Free from accelration\decelration)
Measureing the difference between higest and lowest
What does variability indicate
The baby wellneing
Normallly: 2-25
What if the variability is:
<3:
3-5:
>25:
- absent (compromised if >40min)
- Decreased (problem)
- increased (problem or fetal movement)
Name pathological causes of increased variability > 25 bpm
1- mild hypoxia
2- fetal gasping
3- unknown
How to intervene in marked variability
Attach fetal scalp electrode and measure PH
differentiate between acceleration\deceleration and variability
Variability is still within the baseline
Wheras the acceleration\deceleration is any increase or decrease beyond the baseline
What is prolonged acceleration
More than 2 minutes
Less than 10 minutes
What is tachycardia in terms of acceleratio
> 10 minutes
Differentiate the normal acceleration at <32 and 32 + beyond
- <32: 10bpm for 10sec
- 32 & beyond: 15bpm for 15sec
All should be less than <2 min
What could be the causes for absent accelration
Hypoxic acidemia or fetal abnormality
What are the types of deceleration?
1- early
2- variable (uncomplicated or complicated)
3- late
What is early deceleration
Decerlation that concide with contractions
Onset deceleration= begining of contractio
Ending \ = ending
Peak = peak
Fetal head compression gives an image of which type of deceleration
Early deceleration
What is late deceleration usually associated with
Uteroplacental insufficency
Fetal acdemia
How is late deceletion
Peak of contraction = start of deceleration
Variable deceleration is commonly caused by
Vagal stimulation due to cord compression
Could be associated with fetal acidemia
What causes prolonged deceleration
Cord compression or prolapse - oligohydaminos
What is the action taken in prolonged deceleration
Vaginal exam to rule out cord prolapse - prepare for delivery
Where do we commonly see variable deceleration
Late stages of labor
What does variable decleration mean
Deceleration not associated with uterine contraction
How to manage oligohydraminos?
- Change position of mother
- give IV fluid
- oxygenate
- scalp PH
Sinusoidal pattern is associated with
Severe fetomaternal anemia, hemorrhage, abruptio placenta
Severe blood insufficency
What should be the next step after diagnosing sinusoidal pattern?
Should be delivered immediately
In which cases should we immidiately plan for delivery
1- absent variability (+late or variable deceleration or bradycardia)
2- sinusoidal pattern
What are the benifits of fetal scalp blood
Reduce the increased operative intervention
At which week is fetal scalp blood sampling approrpriate?
> 34
What are the contraindications for fetal scalp sampeling
- Family history of hemophilia or bleeding disorder
- face presentation
- maternal infection or intrauterine sepsis
When is delivery indicated
PH <7.2
Or 7.21-7.24 if rapid fall since last sample
