Developmental Aspects of Lung Disease Flashcards
What happens in the embryonic phase?
Formation of the major airways, too primitive, no gas exchange
What happens in the pseudo-glandular phase?
The lobes develop
Bronchii and secondary bronchii develop
Acinar tubules and terminal buds form
No blood vessels yet, gas exchange
When does the alveolar phase stop?
Continues after birth
2-3 years
Type 1/2 pneumocytes
When does the diaphragm fully seal?
Closure by 18th week
What happens in the lungs developmentally postnatal?
Alveolar separation continues
Increased alveolar dimensions
During what weeks is the embryonic phase?
3-8 weeks
During what weeks is the pseudo-glandular phase?
5-17 weeks
During what weeks is the canalicular phase?
16-26 weeks
During what weeks is the saccular phase?
24-38 weeks
During what weeks is the alveolar phase?
36 weeks
To 2-3 years (postnatally)
What happens during the canalicular phase of lung development?
Last generations of the lung periphery formed
Epithelial differentiation
Air blood barrier formed
What happens during the saccular phase of lung development?
Expansion of air spaces
Surfactant detectable in amniotic fluid
What is a tracheo-oesophageal fistula?
When there is the failure of separation of the trachea and the oesophagus
What lung diseases can be developed during the embyonic phase?
Tracheal, laryngeal stenosis
Pulmonary agenesis
Tracheo-oesophageal fistula
What is the function of surfactant?
Stabilises alveoli and promotes gas exchange
What type pneumocytes create surfactant?
Type 2
What does surfactant act like?
A detergent
What condition can surfactant deficiency cause?
Hyaline Membrane Disease
What is the treatment for hyaline membrane disease?
Antenatal glucocorticoids Surfactant Replacement Oxygen CPAP Mechanical ventilation
What are antenatal fetal origins of lung disease?
In utero nicotine exposure
Nutrition
Low birth weight
Micronutrients
What are post-natal fetal origins of lung disease?
Infection
Growth
Environmental pollution
Micronutrients/vitamins
What is the 3rd leading cause of death in the world?
COPD
What is the major cause of COPD?
Heavy smoking
What is a diaphragmatic hernia?
When the abdominal cavity shifts up, small intestine in the lung causes hypoplasia
