- air trapping and hyperinflation- air pass into area distal to obstruction but air is only partly expired
- expiration usually passive so less force is availabel and forced expiration causes collapse of bronchial wall, further resistance to expiratory flow, residual volume increases, more difficulat to inspire and cough
Total obsruction in asthma effects?
- mucus plugs which leads to atelectasis and collapse
- hypoxia exacerbated by increased metabolic activity associated with increased muscle activity and stress
- respiratory and metabilic acidosis results- blood and body fluids more acidic- neural and cardiovascular system effects
- hypoxemia cause vasoconstriction in pulmonary blood flow causing increased workload on right side of heart
what is atelectasis?
partial or completely collapsed lung
What is chronic obstructive disease (COPD)?
involves progressive and irreversible damage to lungs
What does COPD induce?
- severe hypoxia or hypercapnia (high amount of CO2 in blood)
- right sided heart failure due to cor-pulmonale (enlargement of the right ventricle due to increase blood pressure in the lungs)
What conditions does COPD invlude?
may be a mix
What is emphysema?
the destruction of alveolar walls and septae
Results in large permanently inflated alveolar air space
Loss of elastin function
Note there are many types of emphysema
WHat is dyspnea?
hard to breath or labored breathing
What is a pink puffer?
a pt with COPD and severe emphysema who have a pink complexion and dyspnea
Hyperinflation/dyspnea in order to maintain oxygen levels.
What are the different types of emphysema?
What is centrilobular emphysema
- airspaces in centre of lobules
- common in smokers
What is panlobular emphysema?
- all airspaces distal to terminal bronchioles
What is paraseptal emphysema?
Affects periphery of lobules
What is irregular emphysema?
where different areas of the lungs are affected.
What are the contributing factors to emphysema?
What are the genetic contributing factors to emphysema?
deficinecy of the enzyme- alpha,- antitrypsin
normally inhibits the activity of prooteases (such as elastase) relaeased form neutrophils during inflammation
breakdown of elastin- decreased recoil
What are the contributing factors to emphysema does smoking have?
Increases neutrophil number in the alveoli
Decreases the effect of alpha1 antitrypsin
increases elastase release and activity
Bacteria presentwith infection produce proteases
What does alpha1- antitrypsin do?
inhibits the digestive action of elastase on the tissues of the lungs
Empysema contributing factors
What are the progressive effects of emphysema?
Breakdown of the alveolar wall
Fibrosis and thickening of bronchial wall
Prosressive difficulty with expansion
What happens with emphysema and the breakdown of the alveolar wal?
loss of SA for gas exchange
Loss of pulmonary capillaries
Loss of elastic fibres
Altered ventilation-perfusion ratio
Loss of support for other structures resulting in collapse
What happens with emphysema and the fibrosis and thickening of bronchial wall?
Interference with passive air flow
What occurs with emphysema and the progressive difficulty with expanison?
What is chronic bronchitis?
Significant changes in the bronchi associated with irritation. uch as smoking and air pollution
What occurs with thosewith chronic bronchitis?
Hyper- secretion of mucus
chronic productive cough
Obstruction and inflammation
What is a blue bloater?
Those with chornic bronchitis
- hypoxia, cyanosis (bluish colour of the skin) and edema
Clinical manifestations of low O2 levels
What are the progressive effects of chronic bronchitis?
irritant causes mucosa to become inflamed and swollen
hypertrophy and hyperplasia (The enlargement of an organ or tissue caused by an increase in the reproduction rate of its cells) of musous glands and goblet cells. Increase secretions and decrease ciliated cells.
Further inflammation- fibrosis and thickening of bronchial wall, narrowing of airways- obstruction. Increase secretions which may pool = obstruction
Increased risk of infection- purulent exudate- bacteria become embedded in secretions
Low O2- cyanosis with coughing
Severe dyspnea and fatigue
What is pulmonary ventilation?
the physical movement of air in and out of lungs
Uses contraction/ relaxation of intercostal mm and diaphragm
Designed to maintainair flow to alveoli
ensures O2 is delivered and CO2 is removed.
What is boyle's law and what to do with?
P1V1 = P2V2
Changes of the intrapleural pressure in the lungs to encourage the air to move in and out of the lung.Low pressure air goes in high pressure air goes out
What is maximal inspiration?
The amount of air a person can inhale abou 6000ml
What is inspiratory reserve volume?
Maimum amount of air that can be inspired over normal breathing.
What is vital capcity?
Volume of maximal inspiration and expiration
What is inspiratory capacity?
Volume of maximal inspiration
What is total lung capacity?
Maximum volume the which the lungs can be expanded with a great deal of effort.
What is maximal expiration?
All the way breathing out
What is tidal volume?
Volume inspired and expired with each normal breath
What is expiratory reserve volume?
Maximum volume that can be expired after the expiration of a normal breath
What is residule volume?
Volume that remains in the lungs after a maximal expiration
What is functional residual capacity?
Volume of gas reamingin in lung after normal expiration