Class 4 - fetal health and surveillance Flashcards
What is important factor in fetal well being and why?
Utero-placental function
because of GAS EXCHANGE
blood flow/nutrients
What are the 3 important shunts in the fetal heart?
- ductus venosus - shunts to inferior vena cava
- Foramen Ovale - shunts to vital organs from placenta
- Ductus Arteriosus - takes blood away from the heart
What transports O2 TO Fetus, arteries or veins?
Veins (oxygenated blood)
What transports Co2 AWAY from the fetus, arteries or veins?
arteries (deoxygenated blood)
What substitutes the lungs in the fetus for gas exchange?
the placenta
What is placental function dependent on?
Maternal blood pressure supplying circulation
What two things can decreased circulation to the placenta lead to for the fetus and neonate?
- negative fetal outcomes:
-IUGR
- fetal hypoxia
- metabolic acidosis (too much H)
- still born (fetal death) - Neonatal outcomes
- small for gestational age
- low birth weight
- metabolic acidosis
- seizures
- cerebral palsy
- neonate death
What is a common disorder in neonates when placenta is not effectively perfused?
Cerebral palsy
Why are we worried about someone going too far over 40 weeks?
the placenta starts to calcify
decrease gas exchange
What maternal factors can lead to issues with placenta gas exchange?
-contractions (yes big stressor) – try to space them out, give them a break between contractions
-hypotension
-hypertention
-seizures
-meds /pain meds (opiods - depress resps
- smoking
What are three factors that can affect a placenta from good gas exchange?
- infection
- placental abruption
- placenta previa
What can the fetus do by accident that restricts gas exchange for the placenta?
cord compression
What can affect oxgyenation in labour?
contractions
it’s like baby has to hold their breath until the contraction is over.
- too many
- too long can be a problem
When do we do FHS with FHR monitoring?
- Third trimester
- labour and birth
What are the 3 goals of the FHS (fetal health surveillance) ?
- detect - potential decompensation
- Intervene - early enough
- prevent perinatal/neonatal morbidity and mortality
Since we can’t measure the fetus brain, what test do we do to help us identify patterns of concern?
FHS (fetal health survellance)
- NST
- BPP
-sometimes a contraction test (rare)
When someone has contractions, is FHR necessary?
YES! FHR is ALWAYS assessed with uterine activity (contractions)
what is resting tone?
the rest period for the fetus between contractions
how do contractions affect the placenta/gas exchange on a physiological level?
contractions increase pressure in the blood vessels.
vessels begin to collapse and restrict blood flow to placenta
What is Tachysystole?
too many contractions
> /= 6
or last over 90 sec
in 10 min
What interventions can we do for tachysystole?
- slow down contractions:
1. reduce augmentation or stop induction
2. fluids
3. monitor to see fetal response.
What is the correct amount of time to allow fetus to correct itself after contraction intervention?
30 min
What is normal contraction frequency?
</= 5 in 10 min
What three purposes do contractions serve for labour?
- cervix to thin & dilate
- fetus decend further into birth canal
- birth placenta and membranes
What are the 4 things we monitor during contractions?
1.Frequency – how often – from the beginning to the end of 1
2.Duration- how long
3. Intensity – palpate uterus
4. Resting Tone – time in between
How do we measure contraction intensity?
Manual!
1. weak - feels like my nose
2. moderate/mild- feels like my chin
3. severe/intense - feels like my forehead
How long do contractions normally last?
45-80 seconds
max 90 sec
Aside from contraction frequency >5 / 10 min averaged over 30 min, what are the 3 other factors that can be considered tachysystole?
- contraction >90 sec
- resting tone is <30 sec
- uterus remains firm (>25mm Hg via internal monitor)
What is IA?
Intermittent auscultation
(the doppler)
What is Electronic fetal monitoring (EFM)?
continuous
monitors
1. contractions
2. FHR
What do the top and bottom sensor monitor with EFM?
top- contractions - toco
bottom- FHR - ultrasound
What are the 3 things we want to check with intermittment auscultation?
- baseline of fetus (FHR)
- Rhythm of FHR
- accelerations /decelerations
What do we do if we hear decelerations with the IA?
put them on EFM (the monitor)
What is a normal fetal HR?
110-160 bpm
What 5 things do we look for in electronic fetal monitoring (EFM)?
- FHR baseline
- FHR variability
- Presence of accelerations or decelerations
- contractions
- FHR pattern
What 4 things do we monitor with contractions?
- frequency
- duration
- intensity
- resting tone
How many min of FHR tracing do we need to determine baseline?
10 min of segment
(at least 2 min in a 10 min segment)
What do we not include when looking at baseline?
accelerations
decelerations
marked variability