Newborn circulatory system

Question 1

what is the gelatinous substance of the umbilical cord that insulates and protect the umbilical arteries and vein (AVA) in the womb called?

Answer 1

Wharton’s jelly

Question 2

what causes Wharton’’s jelly to constrict around the 2 umbilical arteries and the umbilical vein? (AVA)

Answer 2

when the baby and umbilical cord is birthed, Wharton’s jelly immediately responds to the cold air (decreased temperature) outside of the uterus by contracting down on the blood vessels. This response helps to facilitate clamping of the cord causing high resistance in the placenta. Basically acting as a natural cord clamp. This high resistance in the placenta is going to aid in blood flow from the placenta to the newborn.

Question 3

the umbilical vein which carries blood to the fetus is branching internally to connect with?

Answer 3

the ductus venosus and the portal vein

Question 4

right-to-left shunts that allow 90%of blood flow to bypass the lungs are created by?

Answer 4

the ductus arteriosus and the foramen ovale

Question 5

where is the ductus venosus located?

Answer 5

between the pulmonary artery and aorta

Question 6

where is the foramen ovale located?

Answer 6

in the membranous septum that divides the right and left atria.

Question 7

the separation of the neonate from the placental circulation results in?

Answer 7

the cessation of blood flow which contributes to the collapse of the umbilical vein and arteries.

Question 8

what is the normal neonatal circulating blood volume?

Answer 8

varies from 85-90 ml/kg

Question 9

what can affect the circulating blood volume?

Answer 9

blood flow in fetal life, the gestation of the infant and the time of clamping of the umbilical cord

Question 10

what is the average haemoglobin range?

Answer 10

15-23.5 g/dl (dl is deciliter, 1 dl = 100ml)

Question 11

diuresis in the first week can result in a loss of what percentage of body weight in the newborn?

Answer 11

5%-10%