pathology of lung disease Flashcards
which cells in the lungs make mucus
goblet cells
what epithelium is found in the lungs
pseudostratified ciliated columnar epithelium
whats the difference between type 1 and 2 pneumocytes
type 1 are flattened and make up 95% of the alveolar surface. type 2 are rounded and make surfactant.
define FEV1
- Forced expiratory volume in 1 sec. the volume that can be forcibly exhaled in the first second of forced expiration.
define FVC
forced vital capacity. the maximum volume of air that can be forcibly exhaled out of the lung until no more can be expired.
whats the lung TLC
total lung capacity.
whats the lung PEFR
peak expiratory flow rate. max flow achieved during forced expiration.
6 causes of obstructive lung disease
acute - foreign bodies, bronchiolitis
recurrent acute - asthma
chronic - chronic brochitis, emphysema, bronchiectasis.
define chronic bronchitis
chronic sputum production usually accompanied by chronic cough, occuring on most days for three months of the year, for 2 or more consecutive years.
pathogenesis of chronic bronchitis
1 - chronic irritation eg cigarrette smoke or air pollution
2 - mucus hypersecretion to protect, submucosal gland hypertrophy and hyperplasia in the larger airways, increased numbers of goblet cells in small airways.
3 -damage and death of ciliated cells (reduced mucociliary action), secondary infection, inflammation and fibrosis.
- partially reversible on stopping smoking.
what is cor pulmonale
Pulmonary heart disease (New Latin pulmōnāle, of the lungs), also known as Cor pulmonale (Latin cor, heart + of the lungs) is the enlargement and failure of the right ventricle of the heart as a response to increased vascular resistance or high blood pressure in the lungs (pulmonary hypertension).
what is emphysema
Definition is Pathological:
An abnormal permanent increase in the size of air spaces beyond the terminal bronchioles with destruction of their walls but without fibrosis
In a highly compliant lung, as in emphysema, the elastic tissue is damaged by enzymes. These enzymes are secreted by leukocytes (white blood cells) in response to a variety of inhaled irritants, such as cigarette smoke. Patients with emphysema have a very high lung compliance due to the poor elastic recoil, they have no problem inflating the lungs but have extreme difficulty exhaling air. In this condition extra work is required to get air out of the lungs. Compliance also increases with increasing age.
what are the subclassificatiojns of emphysema
---Centriacinar (centrilobular) > common -cigarette smoking -chronic bronchitis -upper zones of lung -secondary to airway inflammation (increased protease activity)
—-Panacinar (panlobular)
-α1 – antitrypsin deficiency
(decreased anti-protease activity)
-lower zones of lung
-Homozygotes (PiZZ) onset <40 yrs
-Heterozygotes must smoke
histopath appearance of end stage empysema
End-stage
emphysema has
cystic alveolar spaces
visible macroscopically
- alevoli are dilated and their boundaries broken.
Lung Function Tests n empysema
Reduced FEV1 to <0.7)
Reduced PEF
Increased TLC
Also reduced diffusion capacity
loss of the elastic recoil causes premature closure of the small airways (decreased radial traction causes collapse).
what is COPD
Chronic obstructive pulmonary disease
Defined by lung function tests
Combination of bronchitis & emphysema
Secondary to smoking
Most have mixture of symptoms
‘Pure’ disease at each end of spectrum
COPD Treatment and Prognosis
Prevention & supportive therapy
Stop smoking
Oxygen therapy if hypoxic Pulmonary rehabilitation (exercise & education programme for patients to increase mobility, understand their disease, cope with their breathlessness by pacing their activities, improve anxiety and depression)
5-10% of all deaths in UK
