Types of respiratory diseases:
What happens in obstructive diseases?
What is airway resistance
the ease with which air can flow into and out of the lungs
What is outflow pressure?
The rate at which we can exhale
What effects do restrictive diseases have?
Reduced compliance
What is compliance
The extent to which our lungs increase in volume in response to a given pressure change
How do we measure airway resistance?
Using FEV1 (the forced expiratory volume in the 1st second) - taken as a percentage of the total vital capacity
What is a normal FEV1
80% of vital capacity
What do we use FEV1 for?
Name the obstructive pulmonary diseases:
what happens in chronic obstructive pulmonary disease:
What kind of respiratory tract diseases can you get?
upper and lower
How many people die annually from COPD?
3 million
-3rd leading cause of death in the world
Acute Bronchitis:
Chronic bronchitis: what happens
Chronic bronchitis: causes
80% smoking, sometimes environmental irritants
Chronic bronchitis: treatments
Chronic bronchitis: symptoms
Chronic bronchitis: lasts for
3 consecutive months in 2 years
Emphysaema: causes
smoking or an alpha1 trypsin deficiency (2% of COPD patients)
20% of smokers will develop emphyseama
Emphysaema: treatments
Emphysaema: what happens
-irritants in smoke cause neutrophils and macrophages to release elastase
-elastase breaks down alveolar walls reducing surface area
-significantly high compliance
-increased residual volume and FRC because damaged alveoli retain air
-chronically over inflated lung
-reduced vital capacity
-inefficient gas exchange
-Hyperventilation because of excess CO2 in lungs (to get rid)
(-alpha1 antitrypsin inhibits elastase action)
Emphysaema: symptoms
what does high compliance indicate?
loss of elastic recoil