Pulmonary Pathology 1 Flashcards
what are the requirements for normal fetal lung development?
space in the thoracic cavity; ability to inhale
what is important about the histology of the trachea and main bronchi?
it has to be a big patent open airway so that air can readily move through it in large volumes
what is the normal bronchial histology from lumen side to basal side?
ciliated respiratory epithelium, smooth muscle & submucosal glands, cartilage
what is the purpose of the cartilage in the trachea and main bronchi?
it keeps the airway open
what is the predominant histology of the actual lung tissue?
alveolar perenchyma
what is occurring in the alveolar sac?
gas exchange–> RBCs are releasing their CO2 and they are oxygenating
what is the role of the type 1 pneumocytes?
facilitate gas exchange
what is the role of the type 2 pneumocytes?
produce surfactant and replace type 1 pneumocytes
what is the role of alveolar pores (of Kohn)?
allow aeration but also bacterial cells/fluids to travel between alveoli
what are 4 congenital pulmonary anomalies?
pulmonary hypoplasia, foregut cysts, CPAM, pulmonary sequestration
what 2 broad things could lead to pulmonary hypoplasia?
reduced space in the thoracic cavity, impaired ability to inhale
what could cause reduced space in the thoracic cavity?
diaphragmatic hernias
what 3 things could cause an inability to inhale?
oligohydramnios, airway malformations (tracheal stenosis) or chest wall motion disorders (arthrogryposis)
when does pulmonary hypoplasia become incompatible with life?
if lung weight is less than 40%
what are foregut cysts?
duplications cysts–> detached outpouchings of foregut
what are the complications associated with foregut cysts?
rupture, infection, airway compression
how do foregut cysts continue to grow?
there are still submucosal glands present–> mucin builds up
what is congenital pulmonary airway malformation?
arrested development of pulmonary tissue with formation of intrapulmonary cystic masses
what are the consequences of CPAM?
can be deadly due to hydrops or pulmonary hypoplasia; can get infected later in life
what are pulmonary sequestrations?
non-functioning lung tissue that forms as an aberrant accessory lung bud typically in the region of the left lower lobe
how are pulmonary sequestrations characterized?
lack of connection to the tracheobronchial tree; independent arterial supply
what are the extralobar pulmonary sequestrations associated with?
other anomalies like diaphragmatic hernias
what is atelectasis and what are the three forms?
incomplete expansion of lung parenchyma; resorption (obstruction), compression, and contraction
what are the stages of ARDS?
exudative, proliferative, and fibrotic
