Physiology of Birth

Question 1

What are the three physiology changes in birth?

Answer 1

Circulation
Oxygen
Nutrition

Question 2

What closes parts of the fetus circulation

Answer 2

Foramen oval
Ductus arterios
Ductus venosis

Question 3

Why does the foramen oval close?

Answer 3

Pressure changes in atria

Question 4

Why does the ductus arterios close?

Answer 4

Increased oxygenation of blood

Question 5

Why does ductus venosis close?

Answer 5

Don’t know why

Question 6

After birth, fetus blood now goes where?

Answer 6

Goes to the lungs and liver

Question 7

After birth, what decreases for newborns?

Answer 7

the pulmonary vascular resistance decreases

Question 8

What does the reduction of pulmonary vascular resistance cause?

Answer 8

reduces resistance to blood flow through the lungs

Question 9

After birth, what increases for newborns?

Answer 9

the systemic vascular resistance increases

Question 10

What does the increase in systemic vascular resistance cause?

Answer 10

increases aortic pressure and pressure in left atrium and ventricle

Question 11

How do we know if the circulation is transitioning well?

Answer 11

Check for

• HR
• RR
• Cap refill on sternum
• Blood pressure in all four extremities

Question 12

When newborn is born, if all is good what are the normal findings?

Answer 12

Neonates begin to breathe within seconds

Normal RR within less than a minute

Question 13

When is breathing initiated?

Answer 13

by sudden exposure to exterior world and slightly asphyxiated state

Question 14

What might interfere with that?

Answer 14

Meconium

Cord compression

Question 15

How long can neonates without breathing?

Answer 15

Neonates can survive as long as 10 minutes without breathing

Question 16

When does permanent damage occur?

Answer 16

Serious damage often occur if breathing is delayed for more than 8-10 minutes

Question 17

What is required to open the collapsed alveoli of neonates right after birth?

Answer 17

Lots of negative intraplural pressure (the first cry)

Question 18

When is the alveoli fully formed?

Answer 18

by 36 to 38 weeks

Question 19

When is surfactant produced?

Answer 19

In week 24

Question 20

How do you know if this transition is going well or not?

Answer 20

Check for

• RR
• HR

Question 21

What do neonates use up first in terms of nutrition?

Answer 21

They initially use their own stored glucose but lasts only for a few hours

Question 22

What is stored for a few days?

Answer 22

fats and proteins

Question 23

When they run out of fats and proteins we will see a weight loss of how much?

Answer 23

Up to 20%

Question 24

When will they gain it back?

Answer 24

in 2 weeks

Question 25

If neonate doesn’t want to eat right away after birth, should mothers worry?

Answer 25

No, they have stored fats, proteins and glucose

Question 26

How do you know if this transition is going well or not?

Answer 26

Wet and dirty diapers