Obstructive airway diseases Flashcards
What are Chronic Bronchitis and Emphysema better known as?
Chronic Obstructive Pulmonary Disease (COPD)
What is the normal FEV1/FVC ratio?
0.7-0.8 ( 70-80%)
What is predicted FVC based on?
Age, Sex and height
What does PEFR stand for?
Peak Expiratory Flow rate
What is the normal range for PEFR?
What % is considered a moderate fall?
What % is considered a marked fall?
400-600L/min
50-80% of best is moderate fall
less than 50% is marked fall
Is FEV1 and FVC reduced in obstructive lung diseases?
FEV1 is REDUCED
FVC may be reduced
FEV1 is less than 70% of FVC
Is Bronchial asthma considered a reversible airway obstruction?
Yes, spontanwously or as a result of medical intervention - Smooth muscle contraction and inflammation can be modified by drugs.
What are the Aetiologies of Chronic Bronchitis and Emphysema?
SMOKING
Atmospheric Pollution
Occupation : dust
Alpha-1-antiprotease (antitrypsin) deficiency is an extremely rare cause of emphysema
What else can affect the likelyhood of developing Chronic Bronchitis and Emphysema?
Effect of age and susceptibility
Prevalence
Men > Women but…
Increasing in developing countries
Complicated Chronic Bronchitis is when sputum turns mucopurulent or FEV1 falls. What do these mean?
Mucopurulent = mucus and pus, due to acute infective exacerbation (there has been an infectionn and made it worse, now coughing up pus an dmucus).
FEV1 falls = patient can no longer breathe out as much air in 1 second as they could before.
What are the Morphological changes in ‘Chronic Bronchitis’
Large Airways:
- Mucous gland hyperplasia
- Goblet cell hyperplasia
- Inflammation and fibrosis is a minor component
Small Airways:
- Goblet cells appear
- Inflammation and fibrosis in long standing disease
Emphysema Pathological Definition:
Increase beyond the normal in the size of airspaces distal to the terminal bronchiole arising either from:
and without:
Increase beyond the normal in the size of airspaces distal to the terminal bronchiole arising either from:
dilatation or from destruction of their walls
and without obvious fibrosis.
What are the 4 forms of Emphysema in order of most common to least common and what are the differences?
CENTRIACINAR:
Cigarette smoke, irritants only reach first alveoli so mainly only affects central part, distal parts of lungs often normal.
PANACINAR:
Often caused by Alpha-1-Antitrypsin deficiency, like centracinar except not just central, affercts whole lung/large section sof the lungs. Macrophages within alveoli produce proteases, to help mop up unwanted stuff. Proteases can damage cells is not cleared away by alpha-1-Antitrypsin.
PERIACINAR (‘Blebs of Bullous emphysema’) - tissue losss around the edges of acini - esp tissue loss from cells up against the pleura. Easily cause phneumothorax.
SCAR ‘ irregular’ - no clinical significance
‘Bullous emphysema’
What type of disease is Bronchial Asthma. What happens?
Hypersensitivity disease-
degranlation of mast cells releases chemical factors:
induces inflammation - attracts inflammatory cell types - swelling and edema.
chemicals directly affecting the bronchiole smooth muscle and causing it to constrict
What is the Acinus?
Everything beyond the terminal bronchiole, (gas exchange tissue part) inc. Alveoli, alveolar duct, respiratory bronchioles.
1-2cm accross, conducting airways
What is a “Bulla”?
Emphysematous space greater than 1cm
What is a “bleb”?
Bulla/emphysematous space just underneath the pleura
What effect does smoking have on protease-antiprotease balance?
Smoking induces a protease-antiprotease imbalance?
What is chronic (hypoxic) Cor Pulmonale?
Hypertrophy of the right ventricle as a result of hypertension in the pulmonary system due to systemic pulmonary vasoconstriction as a result of hypoxia (poor perfusion).
What can Cor Pulmonale lead to?
Heart dilataation, Right heart failure,
centri-acinar emphysema begins with dilatation of…?
entri-acinar emphysema begins with dilatation of the respiratory bronchiole, and then progresses to loss of alveolar tissue.
asymmetrical chest expansion is suggestive of…?
asymmetrical chest expansion is suggestive of lobar collapse or pleural effusion
What are the signs of respiratory distress in children as a result from trying to draw breath in through an obstructed airway?
tracheal tug, abdominal breathing, subcostal recession, intercostal recession and head bobbing
Normal normal FEV1:FVC is about …?
0.7-0.8.
What is The initial treatment for asthma in children over 5?
Very low dose inhaled steroids are the initial treatment for paediatric asthma
is it likely that allergies cause the development of childhood asthma?
False – it is likely that an underlying abnormality in the epithelium leads to the development of both asthma and allergies.
diagnosis of COPD requires what?
both typical symptoms and history AND typical spirometry showing airflow obstruction.
Is Female sex is a risk factor for COPD?
Yes
In an acute asthma attack, steroids should be given via…???
n an acute asthma attack, steroids should be given orally, or sometimes intravenously.
