COPD Flashcards
Is Airway obstuxn reversible or irreversible in COPD?
Airway obstruction is not reversible or
incompletely reversible by bronchodilators
Features of COPD:
- Chronic inflammation
- Bronchitis
- Small airways fibrosis
- Emphysema
Chronic inflammation involves:
- incr. numbers of macrophages, neutrophils and T lymphocytes
- the inflammatory mediators have not been as clearly defined as in asthma
Bronchitis is:
Attacks of winter morning cough
Progresses to chronic cough with intermittent
exacerbations
Often initiated by an upper respiratory
infection
Emphysema includes:
Destruction of alveoli and elastin fibres in the lung
May be caused by proteases released during the inflammatory response
Causes respiratory failure (b/c it’s a progressive dx)
Destruction of alveoli impairs gas transfer
What are the principal of tx?
- Smoking cessation: Slows the progress of COPD
- Immunizations : Superimposed infections are potentially lethal
- Current licensed txs: (prevent exacerbations-just symptomatic relief)
Do not reduce the progression of COPD
Do not suppress inflammation
Do not prevent development of emphysema
BRONCHODILATORS do what?
Are the main tx.
Provide Symptomatic relief in patients with a reversible component
2 classes of drugs that bronchodilate
Short-acting drugs
- Short-acting anti-muscarinic antagonists (SAMA)
- Short-acting beta agonists (SABA)
Long-acting drugs
- Long-acting anti-muscarinic antagonists (LAMA)
- Long-acting beta agonists (LABA)
Short- acting drugs:
Short-acting anti-muscarinic antagonists (SAMA):
Ipratropium (-ium)
Short-acting beta agonists (SABA): salbutamol
(-ol)
Long-acting drugs
Long-acting anti-muscarinic antagonists (LAMA) :
Tiotropium (-ium)
Long-acting beta agonists (LABA): salmeterol or
formoterol (LABA)
β2-ADRENOCEPTOR AGONISTS
MoA
Dilate the bronchi by a direct action on the β2-
adrenoceptors of smooth muscle
• Independent of spasmogen
β2 -ADRENOCEPTOR AGONISTS
Effects
Inhibit mediator release from mast cells
Inhibit TNF-α release from monocytes
Increase mucus clearance by action on cilia
RoA of β2 adrenoceptor agonists
Given by inhalation ( to minimise any AE & maximise delivery)
Short-acting β2 Adrenergic Agonists (SABA)
Exs. + duration of axn
Salbutamol (albuterol), metaproterenol, terbutaline
Duration of action is 3–5 h
Long-acting β2 Adrenergic Agonists (LABA)
Exs. + Duration of axn
Salmeterol and formoterol
Duration of action is 8–12 h