Obstructive lung diseases Flashcards
What is chronic bronchitis and emphysema known as
Chronic Obstructive Pulmonary Disease
What are the two ways obstructive lung disease be demonstrated
Peak Expiratory Flow Rate (PEFR)
-airflow obstruction = < 50%
Spirometry
- reduced FEV1/FVC ratio
- FEV1 is less than 70% of FVC
- bronchial asthma is normal between attacks
What are three examples of obstructive lung diseases - what do they all have in common
Asthma
Emphysema
Chronic bronchitis
AIR FLOW LIMITATION
What is the mechanism of bronchial asthma
inflammation in the airways with the degranulation of mast cells due to bronchial sensitivity
How can the effect Inflammation and smooth muscle contraction in asthma be reversed
Inflammation and smooth muscle contraction can be revered by pharmacological drugs but can also reverse spontaneously
What is the aetiology of bronchitis and emphysema
Smoking Occupation ageing atmospheric pollution chronic asthma
What is an extremely rare cause of emphysema
Alpha-1-antiprotease (antitrypsin) deficiency
True or false our FEV1 remains constant throughout our life?
What contributes to the biggest decline in FEV1
False, FEV1 decreases with age
Smoking
What is the clinical definition signs of chronic bronchitis
Cough productive of sputum most days
in at least 3 consecutive months
for 2 or more consecutive years
When does bronchitis become complicated
When FEV1 falls
When there is pus - mucopurulent
What morphologies occur on the airways of chronic bronchitis
Mucous gland hyperplasia (enlarge) and Goblet cell hyperplasia/appear increasing mucus production
This leads to Inflammation and fibrosis and an over all narrowing of the airways
if the airways are irritated by something what are they most likely to produce
More mucus
What is the pathology of emphysema
Loss of elastin by destruction or dilation of alveoli wall
Leading to thickening of airways by inflammation and fibrosis
Inflammation triggers neutrophils causing further damage, triggering elastase for further break down of elastin
Loss of alveolar attachment
What part in the respiratory tract is last linked with respiratory epithelium
Respiratory bronchil
What is the overall alveoli and alveolar duct called?
Acinus
What are the different form of emphysema
CENTRIACINAR
PANACINAR
PERIACINAR
What is centriacinar emphysema
Emphysema that occurs at the beginning of the bronchiolar dilation (in-between alveoli branches)
Why is centriacinar emphysema mostly linked to environmental factor emphysema
What is it mostly likely linked to then
The upper zone of the lungs as are less effiecent at clearing due to decreased bloody supply compared to the lower region of the lungs and is more likely to be affected by environmental factors as reach upper airways first
Smoking
What is panacinar emphysema primarily characterised by and where is it most likely to be seen
relatively uniform enlargement of air spaces throughout the terminal bronchioles and alveoli
Located all over the lung
What is periacinar emphysema characterised by
A bulla -emphysematous abnormal airspaces greater than 1cm resulting from the destruction of normal airspace
Located underneath the pleura is called bleb
What is one of the noticeable characteristics of emphysema
Hyperinflation of the chest
What is smokings affect on emphysema
Leads to malfunction of Alpha-1-antitrypsin which increases the production elastase therefore increasing breakdown of elastin
As well causes inflammation recruiting neutrophils which increase elastase, resulting in further breakdown of elastin
= alveoli wall destruction
What is the most important factor in emphysema
LOSS OF ALVEOLAR ATTACHMENTS
Although alveolar attachment can not be reinstated what is possible reversible in COPD cases with pharmacological intervention
smooth muscle tone
inflammation
What aetiology is panacinar emphysema most likely linked to
alpha 1 antitrypsin deficiency
