Fetal-neonatal physiology

Question 1

If placenta is poorly functioning =

Answer 1

Intrauterine growth restriction

Chronic hypoxia

Question 2

Newborns should be

Answer 2

Warm
Sweet
Pink

Question 3

Newborns should not be

Answer 3

Hypothermic
Hypoglycemic
Cyanosed

Question 4

ABCDEFG

Answer 4

Airway
Breathing
Circulation
dont ever forget Glucose

Question 5

Size of newborn airway

Answer 5

2.5-3.5 cm

Question 6

The newborns airway is easily obstructed with

Answer 6

Fluid, blood, meconium

Question 7

Gas exchange can only take place at what stage of lung development?

Answer 7

Terminal sac stage

Question 8

Alveolar phase of lung development occurs at

Answer 8

30 weeks

Question 9

Surfactant is produced at

Answer 9

32 weeks

Question 10

Ex of congenital lung abnormalities =

Answer 10

Diaphragmatic hernia

Pulmonary hypoplasia

Question 11

Diaphragmatic hernia =

Answer 11

Diaphragm failed to develop. Baby is born with bowel on 1 side of chest so lung cannot grow and expand

Question 12

Pulmonary hypoplasia

Answer 12

Incomplete development of the lungs, resulting an abnormally low number or size of bronchopulmonary segments or alveoli

Question 13

What do lungs need in utero to form?

Answer 13

Fluid matrix - formed from kidneys

Question 14

Why might the fetus not have a fluid matrix in lungs?

Answer 14

Chronic leaking
No kidneys (Potters)

Question 15

Surfacts =

Answer 15

Phospholipid, reduces surface tension in alveoli

Question 16

Babies born before surfactant production have

Answer 16

Respiratory distress syndrome

Question 17

Why are some babies surfactant deficient?

Answer 17

• Premature
• Congenital abnormalities
• Myconium aspiration
• Hypoxia - lactiacidosis
• Infection

Question 18

Why does meconium aspiration reduce surfactant?

Answer 18

Blocks airway, neutralises surfactant

Question 19

Respiratory distress syndrome may lead to a

Answer 19

Pneumothorax

Question 20

Respiratory distress syndrome on CXR =

Answer 20

Ground glass appearance
Poorly expanded lungs
Air bronchograms
Small lung volume

Question 21

Ground glass appearance due to =

Answer 21

Fluid, consolidation, alveoli not fully expanded

Question 22

Air bronchograms =

Answer 22

Dark bronchi, due to alveoli around it being white

Question 23

Number of umbilical arteries

Answer 23

2

Question 24

Number of umbilical veins

Answer 24

1

Question 25

Umbilical arteries carry

Answer 25

Deoxygenated blood away from fetus

Question 26

Umbilical veins carry

Answer 26

Oxygenated blood towards fetus

Question 27

Adaptations of fetal circulation before birth:

Answer 27

• Ductus venosus
• Foramen ovale
• Ductus arteriosus
• Increased vascular resistance in lungs

Question 28

Ductus venosus

Answer 28

Shunts blood from umbilical vein to IVC

Question 29

Ducutus arteriosus

Answer 29

Shunts blood from pulmonary artery to aorta

Question 30

Foramen ovale becomes what after birth?

Answer 30

Fossa ovalis

Question 31

Why do lungs have a high resistance before birth?

Answer 31

Hypoxic pulmonary vasoconstriction

Question 32

What closes first after birth?

Answer 32

Foramen ovale

Question 33

What closes last after birth?

Answer 33

Ductus venosus

Question 34

Why/how does the ductus arteriosus close?

Answer 34

High O2, vasoconstriction

Question 35

What can be used to diagnose septal defects?

Answer 35

Echocardiogram

Question 36

What may cause the circulation to fail to adapt?

Answer 36

Lungs:
Surfactant deficiency
Congenital pneumonia
Meconium aspiration

Cardiac:
Duct dependent circulation

Question 37

Duct dependant relies on what?

Answer 37

Ductus arteriosus

Question 38

Duct dependent circulation cna be subdivided into:

Answer 38

• DD systemic
• DD pulmonary
• Both

Question 39

Duct dependent systemic circulation can be due to:

Answer 39

• Coarctation of the aorta
• Critical aortic stenosis
• Hypoplastic left heart syndrome

Question 40

Duct dependent pulmonary circulation can be due to:

Answer 40

Pulmonary artresia
Ciritical pulmonary stenosis
Tricuspid atresia
Tetralogy of Fallot

Question 41

Tetralogy of Fallot =

Answer 41

1. Pulmonary artery stenosis
2. Right ventricular hypertrophy
3. Ventricular septal defect
4. Aorta overlying VSD

Question 42

What is different about the VSD in the Tetralogy of Fallot?

Answer 42

Right to left shunting (due to high pulmonary pressures)

Question 43

Cause of duct dependent systemic and pulmonary circulations

Answer 43

Transposition of the great arteries

Aorta on right, Pulmonary artery on left

Question 44

Transposition of the great vessels leads to

Answer 44

2 separate loops

Entirely reliant on ductus for circulation

Question 45

What does persistent pulmonary hypertension cause?

Answer 45

Patent ductus arteriosus

Question 46

How to treat persistent pulmonary hypertension

Answer 46

BP in lungs down, BP in body higher

• Pulmonary vasodilators (NO)
• Ventilate
• Give surfactant

Question 47

What makes blood cells in fetus?

Answer 47

Yolk sac –> liver –> spleen –> bone marrow

Question 48

Fetal glucose is derived from

Answer 48

Mother (80% maternal level)

Question 49

Why might children of uncontrolled diabetic cause hypoglycemic baby?

Answer 49

Used to high sugars - high insulin

Question 50

Babies at risk of hypoglycemia =

Answer 50

• B blocker mother
• Septic
• Asphyxiated
• High Hb (polycytaemia)
• premature
• Diabetic mum
• Inherited metabolic disorder
• Growth restriction

Question 51

Weight of children =

Answer 51

Lose in week one (no more than 7%)

Should gain back by week 2