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Flashcards in Exam #3 Cardiac Deck (114)
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When we are in the uterus, we do not need our lungs. So they are collapsed down, but they still make surfactant.

since we do not use lungs as a fetus, we get oxygenated blood via the placenta.


From the placenta… oxygenated blood flows through the umbilical vein to the fetus.

Once it enters the fetus….it goes to the liver where we have something that is called the DUCTUS VENOSUS.


What does the ductus venosus do?

It shunts the oxygenated blood straight into the inferior vena cava.


Once the blood has been shunted from the ductus venosus into the inferior vena cava…..Where does it go next?

Into the right atrium.

In a fetus, the problem is that we do not need it to go to the lungs….because of the pressure…we have a trap door that opens called the Foramen ovale.


What does the foramen ovale do?

It is literally a hole between the atriums with a little flap. So blood goes from the right atrium into the left atrium and bypasses the lungs.

And because the pressure is stronger coming from the mother…it keeps it open.


After the blood enters the right atrium and travels through the foramen ovale into the left atrium….where does it go next.

It goes through the mitral valve into the left ventricle and out through the aorta.

Most of it goes from the aorta to the brain.

This is where most of it is shunted


Even though fetal circulation bi-passes the lungs….there is still a little bit of leakage through the tricuspid valve into the right ventricle…into the lungs.

Even though the fetus does not use the lungs….they still need a little bit of blood in order to make surfactant.

Most of the blood needed is given to the brain due to its rapid growth.

This is done though a shunt called the ductus arteriosis.


What does the ductus arteriosus do?

The ductus arteriosus takes most of mommas blood that did


Go through the foramen ovale and shunts it over to the pulmonary vein…to the left atrium….and left ventricle and out to the brain.


When the fetus is done getting the oxygenated blood from momma, how is the blood returned to the fetus to be reoxygenated?

Through the umbilical arteries.


Name the 2 shunting systems that deliver oxygenated blood to the fetus….

Ductus Venosus
Ductus Arteriosus


Which one shunts blood into the pulmonary veins?

Ductus Venosus
Ductus Arteriosus

Ductus Arteriosus


Which one shunts blood into the inferior vena cava?

Ductus Venosus
Ductus Arteriosus

Ductus Venosus


Which one carries oxygenated blood to the fetus?

Umbilical artery
Umbilical vein

Umbilical vein


Which one carries unoxygenated blood away from the the fetus?

Umbilical artery
Umbilical vein

Umbilical artery


Name the 5 fetal circulation structures.

Umbilical vein,
umbilical arteries
Foramen ovale
Ductus arteriosus
Ductus venosus


Fetal Circulation through the heart….

umbilical vein
liver, ductus venosus
inferior vena cava
right atrium
foramen ovale
left atrium
mitral valve
left ventricle
back through umbilical artery
return to the placenta

leak through tricuspid
right ventricle
ductus arterosus
pulmonary vein
left atrium
mitral valve
left ventricle
back through umbilical artery
return to the placenta


When you are born you come out of the vagina…..you take your first breath of life….it is about 40-60 sonometers of pressure that expands the lungs.

When you expand the lungs for the first time….you have changed the whole system.

Meanwhile, when the cord is cut, the pressure of the whole system changes.

The body now has a higher pressure in the lungs, and the placenta is gone.

So the foramen ovale closes.


Why does the foramen ovale close shortly after birth?

because we have more pressure from the lungs expanding for the first time.

Now the blood travels through the heart like it is supposed to.

Change Happens in about 1 min.


A fetus is used to getting ___% oxygen from the mother



Once the cord is cut and the baby is breathing on their own…What percent of oxygen are they now getting?



So when we look at congenital heart problems, we are looking at something that has gone wrong with the setup of ____ ______.

Fetal Circulation


Most babies will do just fine with a congenital heart condition as long as the fetus is in the uterus getting all of their oxygen from the placenta.

True or false


When you put them in their own world, that is when any defects in their heart start showing up.


Congenital defects are classified by what?

Increased blood flow to the lungs and decreased blood flow to the lungs.


After the baby is born, and the cord is cut….

What stimulates the ductus arteriosus to close?

The ductus arteriosus will close slowly ( it constricts) in reaction to the fact that the baby is breathing 21% oxygen.

Also closes in response to a decrease in prostaglandins.


So if we have a good healthy baby (that has not been recusitated), the ductus arteriosus closes and we may hear a _____ in the first 1 - 2 hours of life.


Because it closes slowly


If we have a sick baby, especially a preterm baby…..they will not be getting enough oxygen…This means that their _____ _____ will stay open/patent.

ductus arteriosus

It stays open because they baby is not getting enough oxygen and this is what stimulates it to close (along with dropping prostaglandin levels)


If a newborn baby that was fine originally gets sick later on 4-5 hours later….will their ductus arteriosus open again?


because the body thinks that it is without oxygen and back in the uterus


What are the Pediatric Indicators 
of Cardiac Dysfunction. (6 of them)

Poor feeding

Tachypnea, tachycardia

Failure to thrive, poor weight gain

Activity intolerance

Developmental delays esp. gross motor

Positive family history of cardiac disease


What are we looking for on a cardiac assessment of a child?

History – prenatal and postnatal
Feeding, respiratory
infections, activity

Blood pressure – 4 extremity
Capillary refill


What are the 3 signs that you have an unhealthy baby?

poor feeding

When you see these signs in a baby you have to start going down the list of problems.

Do they have a GI bug?

Do they have any S/s of illness at all?