Peripheral lung disease Flashcards Preview

Cardiorespiratory pharmacology > Peripheral lung disease > Flashcards

Flashcards in Peripheral lung disease Deck (12)
Loading flashcards...
1
Q

list the 3 major types of lung disease

A

asthma -> increased airway resistance (obstructive)

COPD-> emphysema changes lung compliance and also affects airway resistance (obstructive)

fibrosis-> decreased lung compliance (restrictive)

2
Q

what is the pathology of asthma?

A
  • chronic airway inflammation
  • increased airway responsiveness
  • bronchoconstriction –> increased R
  • airway obstruction -> airway obstruction
  • inflammation and infiltration of alveolar walls by immune cells
  • effective airway diameter reduced (mucus plug)
3
Q

what can the pathology asthma lead to?

A
  • decreased alveolar VE –>hypoventilation -> decreased PA02 and increased PACo2
  • decreased PPG for diffusion of 02 and Co2 –> hypoxia (decreased pa02) and hypercapnia (increased paco2)
4
Q

what do lung function tests on patients with asthma reveal?

A
  • reduced FEV1/FVC ratio to 0.25%
  • PEFR reduced
  • bad asthma shows a decreased ratio with continued testing
5
Q

list some relievers for asthma treatment

A
  • these are bronchodilators leading to an acute reduction in resistance
  • b2 agonists -> salbutamol and salmeterol

theophyllines-> aminophylline

  • anti-muscarinics -> ipatropium bromide
6
Q

list some preventers for asthma treatment

A
  • anti-inflammatory steroids -> chronic reduction In inflammation
  • steroids -> counteract airway inflammation -> beclomethasone and prednisolone
  • leukotriene receptor antagonists -> block actions of bronchoconstriction -> montelukast
7
Q

what is the pathology of COPD?

A
  • Alveolar destruction (emphysema) -loss of elastic recoil and airway radial traction + reduced SA for diffusion
  • Airway obstruction (increasing R)
  • Air trapping (air gets stuck in the lungs)–> hyperinflation (barrel chest) and inflammation of airways due to reoccurrence of pathogens in the trapped air
  • Trapped air becomes hypoxic /hypercapnic
  • Elastic recoil of lung tissue keeps airways open
  • COPD–> loss of elastic recoil leads to collapse of airways and increased airway resistance
8
Q

how can COPD be diagnosed via a lung function test?

A
  • Reduced PEFR–> loss of elastic recoil main determinant of expiration
  • Reduced FEV1 <80% predicated
  • FEV1:FVC <70% predicated

Classification of COPD severity based on FEV1

  • Mild -> 50%-80% predicated
  • Moderate -> 30-49% predicted
  • Severe -> <30% predicated
9
Q

what Is the pathology of fibrosis?

A

• Environmental factors, systemic diseases, drug side effects which affect alveoli and lung interstitium–>increase fibroblast proliferation
• Diseases include:
• Idiopathic pulmonary fibrosis
• Idiopathic interstitial pneumonias
• Connective tissue disease (eg rheumatoid disease, systemic sclerosis)
• Extrinsic allergic alveolitis
Sarcodosi

10
Q

what are the symptoms of fibrosis ?

A
  • Dyspnoea (breathlessness)
  • Dry cough
  • Lung crackles
  • Hypoxaemia with hypercapnia
11
Q

what would be viewed under a histological examination?

A
  • increased fibroblast proliferation
  • increased secretion of elastin and collagen
  • Fibrocollagenous thickening of alveoli
  • Decreased lung compliance
  • Increased thickness of diffusion barrier
12
Q

what would the results of a lung function test show in a patient with fibrosis ?

A
  • reduced TLC
  • reduced VC
  • no change in FEV1/ FVC ratio
  • FVC only smaller due to less air in lungs not due to increased resistance of airways