Obstructive and restrictive
respiratory diseases
Lung volumes
• Total Lung Capacity (TLC) - the total volume of the lung, the volume of
air contained in the lung at the end of maximal inspiration
• Inspiratory Reserve Volume (IRV) - volume, which can be inspired
beyond a restful inspiration
• Tidal Volume (TV) – volume of a single breath, usually at rest
• Functional Residual Capacity (FRC) - The amount of air left in the lungs
after a tidal breath out, the amount of air that stays in the lungs during
normal breathing
• Vital Capacity (VC) – maximum volume which can be ventilated in a
single breath
• Inspiratory Capacity (IC) - the maximal volume that can be inspired
following a normal expiration
• Expiratory Reserve Volume (ERV) – volume, which can be expired
beyond a restful expiration
• Residual Volume (RV) – volume remaining in the lungs after a maximum
expiration
Volumes
• Forced Vital Capacity (FVC) - the volume of air
that can forcibly be blown out after full
inspiration, measured in litres
• Forced Expiratory Volume in 1 Second (FEV1)
- the maximum volume of air that can forcibly
blow out in the first second during the FVC
manoeuvre, measured in liters
• FEV1/FVC (FEV1%) - in healthy adults this
should be approximately 75–80%.
In obstructive diseases (asthma, COPD,
chronic bronchitis, emphysema) FEV1 is
decreased because of increased airway
resistance to expiratory flow and the FVC may
be increased (for instance by air trapping in
emphysema). FEV1/FVC is decreased (<80%,
often ~45%).
In restrictive diseases (such as pulmonary
fibrosis) the FEV1 and FVC are both reduced
proportionally and the FEV1/FVC value may be
normal or even increased as a result of
decreased lung compliance
Obstructive lung diseases
•
•
•
•
airway obstruction
restricted expiration
 FEV1,  FEV1/FVC
 compliance, elasticity
normal
• Chronic bronchitis
– Bronchiolitis
• Asthma
• Emphysema
• Bronchiectasia
• Cystic fibrosis
Asthma
COPD
Condition
Major changes
Causes
Chronic
bronchitis
Hyperplasia
and hypersecretion
of mucus glands
Bronchiectasis
Dilation and scarring Persistent severe
of airways
infections
Cough, purulent
sputum and fever
Asthma
Smooth muscle
hyperplasia
Excessive mucus
Inflammation
Immunologic
or idiopathic
Episodic wheezing
cough and dyspnea
Emphysema
Airspace enlargement
Tobacco smoking
Genetic
Dyspnea
and wall destruction
Tobacco smoking
and air pollutants
Symptoms
Productive
cough
Restrictive lung diseases
•
•
•
•
restricted lung expansion
restricted inspiration + expiration
 FEV1,  FVC, FEV1/FVC normal
 compliance, elasticity
• Interstitial diseases – pneumonia
• Fibrosis of lungs – asbestosis,
silicosis
• Restriction to breathing –
pneumothorax, malformities,
fracturae
Signs
• dyspnea
• hypoxemia
• cor pulmonale
Flow volume curves
Normal spirogram
Spirogram in restriction
Spirogram in obstruction
Asthma
• Chronic inflamatory disease of bronchi leading to
spasmatic occlusion and hyperproduction of viscous
mucus
Causes
• allergic
– allergens
– infection
• non-allergic
– neurogenic
– psychogenic
Asthma atack
• acute exacerbation of asthma
Signs and symptoms
• dyspnea, wheezing, catching for air
• cough – viscous sputum
• cyanosis
• tachycardia
• chest pain
Chronic bronchitis
• chronic inflammation of bronchi
Causes
• smoking
• air pollutions
Signs and symptoms
• expectorating cough (productive cough, produces sputum)
• dyspnea, wheezing
• chest pain
• fever
• fatigue and malaise
Chronic bronchitis
Smoking
• impairs ciliary movement
• inhibits function of alveoli macrophages
• hypertrophy and hyperplasia of mucus-secreting gland
• causes smooth muscle constriction
Air pollutions
• ozone
• CO
• SO2
Emphysema
Abnormal, permanent enlargement and destruction of theair spaces
distal to the terminal bronchioles withou obvious fibrosis,
progressively lose elasticity and eventual rupture of alveoli
•Panacinar (or panlobular) emphysema:
The entire respiratory acinus, from
respiratory bronchiole to alveoli, is
expanded. Occurs more commonly in the
lower lobes, especially basal segments,
and anterior margins of the lungs.Typical
for alpha-1-antitrypsin deficiency.
•Centroacinar (or centrilobular)
emphysema: The respiratory bronchiole
(proximal and central part of the acinus)
is expanded. The distal acinus or alveoli
are unchanged. Occurs more commonly
in the upper lobes. Typical for smokers.
Emphysema
Causes
• Inherited
– alpha 1-antitrypsin deficiency
• Acquired
– cigarette smoking
– air pollution
Signs and symptoms
• Dyspnea upon exertion, wheezing, coughing
• Pursed lips to maximize ventilation
• Right heart failure
• Hypoxia, respiratory acidosis
Emphysema
Alpha 1-antitrypsin deficiency (A1AD)
• inflammatory enzymes (such as elastase) destroy the
alveolar tissue
• most A1AD patients do not develop clinically significant
emphysema
• smoking and severely
decreased A1AT levels
(10-15%) can cause
emphysema at a young
age
Chronic obstructive pulmonary disease
• combination of chronic brnchitis + emphysema + asthma
Cause
• Smoking
• Occupational exposures
– coal mining, gold mining, silicosis
• Air pollution
• Genetics
– alpha 1-antitrypsin deficiency
• Other risk factors
– a tendency to sudden airway constriction in response to inhaled
irritants (asthma)
– repeated lung infections
• COPD as an autoimmune disease
– sustained inflammation mediated by autoantibodies and
autoreactive T cells
Chronic obstructive pulmonary disease
Signs and symptoms
• dyspnea, wheezing
• mucous sputum
• respiratory failure
• cyanosis
• cor pulmonale
• peripheral oedema (RV failure)
• tachypnea