Paediatrics

Question 1

What cells produce surfactant?

Answer 1

= type II alveolar cells

Question 2

What is lung compliance?

Answer 2

= a measure of the lung’s ability to stretch and expand

Question 3

At which week gestation do the alveolar cells become mature enough the start producing surfactant? (range)

Answer 3

= between 24 and 34 weeks gestation

Question 4

Which 2 hormones are released in response to stress of labour which help stimulate respiratory effort?

Answer 4

• adrenalin
• cortisol

Question 5

What if the foramen ovale?

Answer 5

= hole between the left and right atria (upper chambers) of the heart

Question 6

What keeps the ductus arteriosus open?

Answer 6

= prostaglandins

Question 7

How does a babys first breath cause the functional closure of the foramen ovale?

Answer 7

= first breaths baby takes expand alveoli > decreasing pulmonary vascular resistance > this causes a fall in pressure in the R atrium > at this point L atrial pressure greater than R atrial pressure > this squashes the atrial septum and causes functional closure of the foramen ovale > this structurally closes and becomes fossa ovalis

Question 8

What is the ductus arteriosus?

Answer 8

= a blood vessel that connects the pulmonary artery to the aorta

This connection is present in all babies in the womb, but should close shortly after birth.