Fetal Circulation Flashcards
Before birth
Blood from the placenta, (——– saturated with oxygen),
reaches the fetus by the ———- vein.
80% - umbilical vein
most of this blood flows through the
————- directly into—————- the, bypassing the ——————-
DUCTUS VENOSUS- inferior vena
cava-liver
Placental blood mixes with—————- blood
returning from the in the IVC
deoxygenated-lower limbs
Then IVC enters the———
right atrium.
Most of the blood from the IVC enters
the left atrium through ———-It then flows into the ——then——
into the aorta
foramen ovale-left ventricle-into the aorta
A small amount from the ———- is prevented
from entering the left atrium and remains in
the——atrium. It mixes with desaturated blood returning
from the head and arms by the ————–
IVC- right - superior vena
cava.
Desaturated blood from the superior vena
cava enters the ——— ventricle and then into
the ——–
right-pulmonary trunk.
blood move from descending aorta then —————— which carry —————– and then —————-and the placenta
umbilical arteries - deoxygenated- umbilical cord
the first arteries rise from aorta are _________and______
coronary artery to supply wall of heart
carotid artery to supply the brain
Resistance in the pulmonary vessels is ————most of this blood passes through the DUCTUS
ARTERIOSUS into the ————It mixes with blood from the —————–It passes through the descending aorta——————-It returns to the placenta by —————–
high- descending aorta-proximal aorta-two umbilical arteries.
The oxygen saturation in the umbilical arteries is
approximately ——————-
58%.
small amount of blood in pulmonary trunk from right ventricle will go to ———–to supply tissue
lung
Circulatory changes at birth : 2things
- Cessation of placental blood flow
- The beginning of respiration.
baby cry after birth because of
start lung working ( beginning of respiration)
Closure of umbilical arteries: by
contraction of smooth musculature in their walls
distal parts of umbilical arteries form ——–
medial umbilical ligaments
proximal parts of umbilical arteries remain open as————–
superior vesical arteries
Closure of umbilical vein to forms the ——————
ligamentum teres of liver
. Obliteration of ductus venosus to form ———-
ligamentum venosum
Closure of ductus arteriosus to form the————
how ? Muscular wall of the duct———— immediately after birth
• The amount of blood flowing through the lung —————rapidly.
ligamentum arteriosum-contracts-increases
Closure of oval foramen
• Pressure in the right atrium ——— as a result of————-placental blood flow.
• Pressure raises in the ——– atrium.
• The septum———— is then apposed to the septum ———-and functionally the foramen
oval closes.
decreases-interruption-left- primum-secundum
closure of the umbilical vein postnatally result in the formation of
ligamantum teres
ductus arterosis prenatally connect
pulmonary trunk with arch of aorta
