Anatomy

Question 1

3 main important shunts in foetal circulation

Answer 1

ductus venosus (shunts oxygenated blood from umbillical vein to IVC to bypass liver)

foramen ovale (shunt oxygenated blood from right to left atrium)

ductus arteriosius (shunts deoxygenated blood from pulmonary artery to inferior aorta)

Question 2

how do the shunts in the foetal circulation change on birth

Answer 2

when they take their first breath, this decreases pulmonary resistance – increases left atrial pressure = closure of foramen ovale
increase in 02 from respiration + reduced prostalandins from placental separation = closes ductus arteriosus

Question 3

post natal derivative of umbillical vein

Answer 3

round ligament (ligamentum teres hepatis)

Question 4

post natal derivative of umbilical arteries

Answer 4

medial umbilical ligament

Question 5

what layers does the pericardial space lie

Answer 5

between the parietal pericardium and epicardium

Question 6

what neve supplies the pericardium

Answer 6

phrenic nerve

Question 7

why does pericarditis cause referred pain to the shoulders

Answer 7

its supplied by the phrenic nerve

Question 8

damage to what artery causes heart block or arrythmias and why

Answer 8

right coronary artery as it supplies the SA and AV node