Chronic Obstructive Pulmonary Disease (COPD) Flashcards
chronic obstructive pulmonary disease
- persistent, widespread inflm of the airway, parenchyma and vasculature
- acute, recurrent & chronic obstr of a/w
parenchyma
epith cells involved in gas exchange at alveolar level
vasculature
vessels involved in gas exchange (ex. pulmonary capillaries)
COPD is a combination of:
- chronic bronchitis
- emphysema (may co-exist with asthma)
et & risks
- smoking (80-90%)
- recurrent resp infects
- aging
- genetic deficiency of a1 antitrypsin
how does smoking cause COPD
- cigarette smoke has irritants that irritate the respiratory tract causing goblet cells to inc mucus production (defense mechanism to protect a/w lining) –> impedes gas exchange
- irritants in smoke damage cilia
- irritants induce coughing which if persistent can inflame a/w lining & alveoli causing further damage
how do recurrent resp infections cause COPD
causes chronic hypersecretion of mucus, coughing and inflammatory damage
how does aging cause COPD
causes degeneration of tissue which dec elasticity + inc compliance of lungs
dx
- Hx, Px
- CXR
- pulmonary Fx tests (spirometry)
- labs (CBC, CRP)
what does Hx & Px assess
- breath sounds
- ventilation issues
- SOB
- accessory muscle use
- arms propped on table to facilitate breathing
CXR purpose
to find consolidation, damage and dec lung vol
spirometry components
- forced vital capacity (FVC)
- forced expiratory vol (FEV1)
- total lung volume & tidal volume
FVC
maximum total volume forcefully exhaled
FEV1
vol of air forcefully exhaled in 1 second
total lung volume + tidal volume
normal volume when no extra effort is being used
Tx
- cessation of smoking
- avoid airway irritants
- vaccines (flu shot)
- drugs (stage-based)
drugs used in early stage (1)
- short-acting beta agonists (aka “B-adrenergic agonists”)
- anticholinergics
drugs used in more advanced COPD (2)
- inhaled steroids
drugs used in late stages (3)
- long-acting B agonists (prescribed w/ glucocorticosteroids)
- Xanthine Derivatives (theophylline)
short-acting beta agonists (aka “B-adrenergic agonists”) (1)
bronchodilators that stimulate B2 adrenergic receptors in the lungs, activating adenylate cyclase to produce cyclic adenosine monophosphate (cAMP) –> triggers relaxation of bronchial smooth muscle
anticholinergics (1)
bronchodilators that block ACh receptors on the bronchial tree so that the PNS is not activated to release more ACh, resulting in bronchodilation
inhaled steroids action (2)
dec inflm by dec release of mediators and limiting WBC activity, and inc responsiveness of bronchial smooth muscle to B-agonists
xanthine derivatives (theophylline) action (3)
- causes bronchodilation by inc levels of cAMP to trigger smooth muscle relaxation
- has anti-inflm action by inhibiting IgE release
