Lung histology and COPD Flashcards
what is the cut off between the upper and lower respiratory tract?
At the larynx
What is the important of the cricoid cartilage?
It’s the only complete cartilagenous ring, can apply pressure during inspiration to try and prevent aspiration of gastric contents.
What is a tumour if it’s within 2cm of the carina?
T3
When standing where are foreign objects likely to impact?
The right bronchus
What is the innervation of the parietal pleura?
intercostal and phrenic nerves
what is the innervation of the visceral pleura?
the vagus nerve and sympathetic nerves
what is the lining of the upper airways?
ciliated pseudostratified columnar epitheilal cells
What are type 1 pneumocytes?
thin flat squamoid cells
what are type 2 pneumocytes?
cuboidal cells that produce surfactant.
where does the lymphatic drainage of the subpleural space go?
to the hilar lymph nodes
what is emphysema?
permanent enlargement of the distal airspaces
destruction of walls
no fibrosis
what is bronchitis?
Presence of a chronic productive cough on most days for 3 months in each of 2 consecutive years
what inflammation is seen in COPD?
CD8>CD4
increase in neutrophils and macrophages
what poteases do neutrophils produce?
elastase, cathepsin G and protease 3
what proteases for macrophages produce?
cysteinine proteases, cathepsin
what is the consequence of more proteases than anti-proteases?
increase mucous release
alveolour wall destruction
what are the main three processes in the pathogenesis of COPD?
- inflammation
- more proteases than anti proteases
- inbalance between oxidants and anti oxidants
what causes mucous hypersecretion in COPD?
squamous metaplasia, increase in the number of goblet cells, increased proteases, increase in size of bronchial submucosal glands
what are the two types of emphysema?
- centreacinar
2. panacinar
what is centriacinar emphysema?
affects the proximal acini are more seen in smokers
what is panacinar emphysema?
uniform enlargement at the lower lobes. there is build up of neutrophils and often AAT deficiency
why can some patients with COPD get liver cirrhosis?
AAT 1 deficiency as it may change shape so can no longer fit through vessels and builds up in the liver
what conditions cause finger clubbing?
Lung cancer
Bronchiectasis
idiopathic pulmonary fibrosis.
what are featurse of cor pulmonale?
raised JVP, loud P2 heart sounds, pulmonary HT, tricuspid regurgitation, pitting peripheral oedema, hepatiomegaly
what MMP proteases are involved in COPD?
8,9,12
why does pulmonary hypertension develop in COPD?
hypoxia causes pulmonary constriction, endothelial dysfunction and remodelling of pulmonary arteries and destruction of the capillary bed.
what are systemic features of COPD?
cachexia, skeletal muscle wasting, increased risk of CVS disease due to increased CRP, normochromic normocytic anaemmia, secondary polycythamiia, osteoporosis, depression
