Pathology of Obstructive Lung Disease Flashcards
What is localised obstruction?
Obstruction of a large airway
What can localised obstruction be caused by?
Lung cancer
Inhaled foreign bodies
Chronic scarring diseases like bronchiectasis and secondary tuberculosis
What are examples of chronic scarring diseases?
Bronchiectasis
Secondary tuberculosis
What is generalised small airway obstruction?
Bronchiolar obstruction
What are some obstructive airway diseases?
Chronic bronchitis
Emphysema
Asthma
What is chronic obstructive pulmonary disease?
A combination of chronic bronchitis and COPD
What is FEV1?
Forced expiratory volume of air exiting the lung in the first second of blowing out of your lungs as fast as possible
What is FVC?
Final total amount expirred
What is FEV1 usually?
70-80% of FVC
What volume is normal FVC1?
3.5-4L
What is normal FVC?
About 5L
What is used to measure FEV1 and FVC?
Spirometry
What is predicted FVC based on?
Age
Sex
Height
What can obstructive lung disease be demonstrated by?
Peak expiratory flow rate (PEFR)
What is the normal peak expiratory flow rate?
400-600L/min
What is the normal range, moderate fail and marked fail of PEFR?
80-100% of best value is normal
50-80% is moderate fail
<50% is marked fail
How does obstructive lung disease affect spirometry and peak expiratory flow rate?
Always airflow limitations
Peak expiratory flow rate is reduced
FEV1 is reduced
FVC may be reduced
FEV1 is less than 70% of FVC
What is bronchial asthma?
Type 1 hypersensitivity in the airways
What is bronchial asthma mediated by?
Immunologically mediated, leading to the degranulation of mast cells
What are the effects of degranulation of mast cells?
Patterns on inflammation in the airways and bronchial smooth muscle contraction
How does mast cell degranulation affect the airways?
Reduce cross sectional area, making breathing difficult
What is important about bronchial asthma?
Reversible airway obstruction either spontaneously or as a result of medical intervention
What can bronchial smooth muscle contraction and inflammation be modified by?
Drugs
What is the aetiology of chronic bronchitis and emphysema?
Smoking
Atmospheric pollution
Occupational dust
Alpha-1-antytrypsin deficiency
Effects of age and susceptability
Do more men or woman have COPD and why?
Men because they smoke more
What is chronic bronchitis?
Cough production of sputum most days in at least 3 consecutive months for 2 or more consecutive years (excludes TB, bronchiectasis)
What is chronic bronchitis easily confused with?
Chronic bronchial asthma
What is morphological?
Size, shape and structure of a given organ
What are morphological changes in the large airways due to chronic bronchitis?
Mucous gland hyperplasia
Goblet cell hyperplasia
Inflammation and fibrosis is a minor component
What is hyperplasia?
Enlargement of an organ or tissue caused by an increase in the reproductive rate of its cells
What are morphological changes in the small airways due to chronic bronchitis?
Goblet cells appear
Inflammation and fibrosis in long standing disease
What is emphysema?
Increase beyond the normal in the size of airspaces distal to the terminal bronchiole arising either from dilation of from destruction of their walls and without obvious fibrosis
What is an acinus?
Everything beyond the last airway which is surrounded entirely by epithelial
What is the size of the normal acinus duct?
1-2cm, cannot see where one ends and where another begins
What disease is this?
Emphysema
What are the different forms of emphysema?
Centriacinar
Panacinar
Periacinar
Scar ‘irregular’
Bullous emphysema
What are emphysema defined by?
Where in the acinus the tissue is lost