Changes at birth with fetal circulation

Question 1

at first breath

Answer 1

decreasing peripheral vascular resistance

Question 2

lung PG dehydrogenase

Answer 2

-destroys PGE2 from placenta

Question 3

what closes ductus arteriosus

Answer 3

O2 sensitive K channels, increased O2 in arterial blood

Question 4

clamping of placenta

Answer 4

low resistance placenta out of circulation

systemic vascular resistance increases

Question 5

over the next 6 weeks, why does PVR do down?

Answer 5

decreased muscular coat of pulmonary arterioles

lowers PVR

Question 6

what happens with the RV?

Answer 6

muscular right ventricle thins as total cardiac output drops and pulmonary resistance falls