Unit 1 fetal development
case study
Elizabeth Kelley Buzbee AAS, RRT-NPS, RCP
Case study # 1
• Your patient is in L & D. She is a 48 year
old LAF. What else do you want to
know about this patient?
Answer:
• Her vital signs: HR 125 sinus tachycardia, RR
18 bpm without retractions, BP 158/90 mmHg
she is afebrile
• Her Sp02: 99% on room air
• Her BS: clear to all lobe, diminished in the
basal areas.
• Pregnancy history: week 28
• Prior medical History: She is G4, P3 A1
• Hx of Gestational diabetes with the last two
pregnancies
• What is the significance of her past
history?
answer
• Her VS are ok, and she doesn’t seem
to have an infection
• She has had 4 pregnancies, and 3 live
births and one miscarriage. This puts
her at risk for premature labor
• She is older, which makes her infant at
risk
• The gestational diabetes puts the
baby at risk
• If born today, the infant will be
premature, but will be viable
• What is the status of her fetus at 28
weeks? What are it’s chances of
survive at this point?
answer
• At 28 weeks the fetus should have enough
pulmonary capillary bed to exchange gas
• There should be enough alveoli for gas
exchange
• The surfactant will be started but may not
be at sufficient levels to prevent respiratory
distress—the maternal diabetes will slow
down surfactant production
• The CNS may not be developed enough to
handle hypoxemia and hypercapnia
appropriately
• What is the blood flow from umbilical
vein to umbilical artery?
Answer:
• Blood from the placenta gets to the
single umbilical vein that goes to the
belly and enters the liver where part of
the blood goes to the portal
circulation and the rest goes into the
IVC via the D. Venosus where it enters
the RA and goes into the Foreman
Ovale & into the LA and LV to go out
into the fetal body
• What happens to the blood in the
SVC?
answer
• The blood in the SVC drains the head
and shoulders and this Desaturated
blood enters the RA goes to the RV
and into the pulmonary trunk where it
is shunted away from the lung into the
D. Arteriosus to the Aorta
• In the descending Aorta, this
Desaturated blood mixes with the
saturated blood from the IVC and
drops the fetal P02 from the mid 30-40s
to the mid 20s
• Labor started with the water breaking
[ruptured membranes] at midnight on
Sunday. The labor was spontaneous,
vertex, vaginal delivery. There were
some early decells
• The baby is born at 0800 on Tuesday.
He is a little boy.
• What if anything is significant about
this series of events?
answer
• The time between the rupture of
membranes and the birth of the baby
exceeds 24 hours. This is called
Premature rupture of membranes
PROM which places the baby at risk for
infection.
• SVVD is normal, but the delivery is
premature
• early decells are not as serious as late
decell. The HR rises back to baseline
after each contraction
The umbilical cord is attached to what?
answer
• To the baby’s belly and to the
placenta
• How many blood vessels should be
present in the umbilical cord?
answer
• Three vessels:
• Two umbilical arteries
• One umbilical vein
• Which of these vessels carries blood
with the most 02 [to the fetus]?
answer
• The umbilical vein carries blood to the
fetus from the placenta
• How do gases and waste product
exchange between the mother and
fetus?
answer
• The maternal blood flow goes to the
maternal side of the placenta. The
Pa02 is 80-100 mmHg.
• The maternal blood is sent into the
spaces around the chonrion villi where
gases diffuse into the fetal blood.
• fetal capillaries in the placenta
regroup into veins that drain into the
single umbilical vein which carries the
saturated blood to the fetus at a P02
of 31-42 mmHg
• At the OB gyn’s request, you draw and
run a cord gas from the umbilical vein .
You get the following data:
• pH 7.34
• P02 40
• PC02 35
• What do you think about these gases?
answer
• This is wnl for cord gases for fetus
between 25 weeks and term
• As soon as the infant starts to breath
these data will change
• The baby takes his first breath. If all
goes well what happens?
answer
• The first few breaths will increase the RV so
that [1] PA02 rises [2] lung Compliance rises
• The rising PA02 will reverse the longstanding
pulmonary HTN and the RV pressure will drop
which lowers RA pressure.
• The rising PA02 will raise the Pa02 and that
will close the D. Arteriosus
• Once the cord is clamped the systemic
blood pressure rises so that the RA pressure is
lower than the LA pressure and the Foreman
Ovale will close.
• At 1 minute of life the baby has the
following:
• Flaccid
• Extremities blue, central cyanosis
• HR 135
• Regular at 55 bpm
• Grimaces with catheter to nose
• What is this infant’s APGAR score at 1
minute? What intervention is needed?
answer
• 0 for muscle tone
• 0 for color
• 2 for HR
• 2 for respiratory effort
• 1 for reflex
• APGAR at 1 minute is 5
What intervention is needed at this
point?
answer
1. Warm and stimulate the baby by
rubbing him down with towel.
2. Attach pulse oximeter to right hand
[post-ductal]
3. Continue to monitor HR and RR
4. Assess the respirations for s/s of
respiratory distress [Silverman score]
• You are blowing 02 to his face. His
Sp02 rises from 75% to 91%
• In 5 minutes, he has the following data:
• HR 140
• Crying loudly [respiratory rate 48 bpm]
• Extremities blue but lips pink
• Arms and legs flexed
• What is his APGAR and what is his
prognosis?
answer
• His APGAR at 5 “ is 7 and his prognosis
is excellent, although he might need
supplementary 02 for a day or so