Chronic obstructive pulmonary disease (COPD) Flashcards
what is COPD?
-acute, recurrent & chronic obstructiion of airways
d/t chronic inflm of airway, parenchyma (alveolar tissuse) & vasculature (capillaries surronding alveoli)
with COPD the disease is ________ but the obstruction is not
chronic
what is the parenchyma
alveolar tissue
what are the two diseases that are part of COPD
- chronic bronchitis
- emphysema
COPD may also co-exist with
asthma
what is compliance?
ease at with which we breathe in and out
if there is more competent tissue in lungs more elasticity & more compliance
what is the etilogy and risks for copd?
- smoking (80%-90%)
- recurrent resp infections (not a common cause)
- ageing
- genetic deficiency of a1 antitrypsin
what is the most common cause of copd causing (80-90%)
smoking
what is a1 anti-trypsin
tyrpsin is an enzyme that breaks down proteins, anti therefor inhibits this enzyme
what is the problem with cigarette smoke and why is it so damaging?
cigarette smoke contains a variety of irritants, an cause production of too much mucus from irritants, impedes cillliary function. irritants cause coughing–to much coughing is injurious. Irritants are going to cause inflm and tissue damage.
what are the three mechanisms of airflow obstruction in copd?
- obstruction of airway caused by hypertrophy of bronchial wall
- inflammation & hypersecretion of mucus causing obstruction
- loss of elastic fibres that hold airway open causing obstruction
what is chronic bronchitis
Inflammation causing obstruction of airway
what is chronic bronchitis due to
smoking and recurrent infection
how does chronic bronchitis present
chronic productive cough
has to be more than 3 months a yr in 2 consecutive years
how does the chronic bronchitis chronic productive cough have to present
has to last for more than 3 months in a yr 2 consecutive years
chronic bronchitis affects _____ airway 1st then _______ airway later
large airway first then smaller airway later
what happens to large airways in chronic bronchitis ?
- large airway affected first
- hypertrophy of submucosal glands causing an increase in mucus secretion
what happens in the smaller airways in chronic bronchitis?
- smaller airways affected after large airways
- increase in golbet cells therefore an increase in mucus secretion
Patho of chronic bronchitis
- excessive quantities of mucus obstruct airways
- mucus is moist, warm, full of nutrients ideal for bacteria growth
- excess mucus –impaired mucociliary defenses–infection —bronchial walls inflm & thickenend— lumen obstruction (mucus&inflm)– airway collapse– air trapped in parts of lung— decrease in alveolar ventilation(air in & out) causing a ventilation perfusion imbalance cause hypoxemia (decrease of 02 in arterial blood)
what is hypoxia and what is hypoxemia
hypoxia=deficencey in 02 systemically in tissues
hypoxemia= hypoxia in arterial blood gases (ABGS)
mnfts of chronic bronchitis
- resp fx impaired: hypoxemia & hypercapina(increase in c02 levels in the blood)
- dyspnea
- activity tolerance
- increase in sputum
- wheezing (narrowing of airways)
- crackles (wet crackles because of mucus & exudate there, when air moves through fluid(exudate/mucus sounds of crackles)
- mucus provides ideal place for infection- recurrent infection is a mnfts
what is Emphysema?
- destruction of alveolar walls & capilllary beds causing:
- enlarged distal spaces
- loss of compliance
Emphysema is the destruction of alveolar walls & capillary beds which causes
enlarged distal spaces & loss of compliance
Etiology of emphysema?
- smoking
- genetic deficiency of a1 antitrypsin (accounts for less than 1%)
what is the problem with a genetic deficency of a1 antitrypsin?
a1 antitrypsin is an inhibitor of trypsin(enzyme), this enzyme is an example of protease it breaks down proteins and this is happening outside of digestive tract so causing tissue damage by breaking down proteins in tissues, a1 antitrypsin regulates so that enzyme not reacting when it doesnt need to
what is the patho of emphysema
-a1 antitrypsin protects lung
-smoking: smoking inhibits a1 antitrypsin(causing enzymes to break down proteins and then tissues)
smoking also brings about inflammatory cells b/c injurious (attracts inflm cells)
-an increase in protease(not regulated) this causes destruction of alveolar walls, then alveoli merge which causes a decrease in surface area
-then there is permanant distended air spaces which causes ventilation to be impaired
-there is air trapped between alveoli which causes an increase in dead space then there is an increase in work of breathing
what is dead space
where there is no gas exchange, capillary wall destroyed causing impaired perfusion, there will then be a ventilation perfusion imbalance (both will be impaired)
bullae
pockets of air trapped in between the alveloli
blebs
smaller areas of air trapped in between the alveoli
what are the mnfts of emphysema?
- dyspnea
- increased ventilatory (respiratory effort)
- barrel chest
what is the difference between a normal chest and a barrel chest?
normal has a transverse diameter:anterior posteiror diameter of 2:1
barrel chest has a transverse diameter: anterior posterior diameter of 1:2 or 1:1
diagnosing COPD?
-history, physical exam
-chest x-ray
-pulm fx tests (spirometery) lung volume,tidal volume
pulmonary fx tests give significant information on how compromised pts lungs are)
-labs start with basic and then move to specialised
treatment of COPD?
- limit progression: no smoking, avoid airway irritants
- vaccines (flushot, pneumococcal)
- drugs (stage based)
- short acting beta adrenergic agonists & anticholinergics
- inhaled steroids
- long acting beta adrenergic agonists (b agonists)
- theophylline (potent bronchodilator)
- other physiotherapy for mucus & mucolytics
what is an antagonsit and what is an agonist
antagonist –antagonizes someone so opposes
agonist–facilitates or helps
the drugs for treating COPD are ?
stage based
what do beta adrenergic agonsits do?
beta adrenergic agonists facilitates the action of Adrenalin (ephinephrine) facilitate the binding of beta relaxes muscles & brings about bronchodilation
what do anticholinergics do?
cholinergic -refers to acetylcholine, preventing acetylcholine, bidning of acetylcholine to smooth muscles causes vasoconstriction, anti is conteracting blocking acetlycholine causing bronchodilation
what is theophylline and what is it other properties
is a potent bronchodilator, additional propertys is that it is anto-inflmmatory will not use solely as anti -inlm b/c there are better drugs but is a bonus because there is inflm with COPD
