pathophysiology Flashcards
what is asthma?
chronic disorder in which airways become narrowed ,leading to breathing difficulties
what can chronic asthma lead to?
- smooth muscle hyperplasia (due to a long time of bronchoconstriction)
- goblet cell metaplasia (over production of mucus)
- mucosal edema
how does allergic asthma come about?
How does eosinophilic asthma come about?
what are the overall symptoms of asthma
- wheezing
- chest tightness
- sob (dyspnea)
- cough (dry or productive)
- air trapping (hyperresonance)
- use of accessory muscles
- V/Q mismatch
- fall of systolic blood pressure of more than 10mmhg during inspiratory phase
what is the overall diagnostic test for asthma?
- arterial blood gas shows increased Co2 and decreased PH
- lung function test (spirometry) Fev1/ fvc ratio (for severity)
- history taking and symptoms
what is COPD?
it is when air is stuck in lungs and cannot be expelled , hyper inflammation
- emphysema
- chronic bronchitis
what are the risk factors of COPD
- smoking
- biomass smoke, occupational exposure
- air pollution
- genetics , female gender
- airway hyperresponsiveness
- asthma
- chronic mucus secretion
- recurrent bronchopulmonary infections
what are the clinical findings that COPD patients usually have?
- airflow limitation , air trapping
- reduced FEV/FvC ratio
- total lung capacity is normal or increased
- reduced vital capacity
what is emphysema ?
it is the destructive changes in alveolar wall and capillary beds , loss of lung elasticity and there are abnormal enlargement of the airspaces distal to terminal bronchioles
hyperinflammation of lungs
Increase in total lung capacity
what are the causes of emphysema?
- genetic disposition
- environmental factors
what is the genetic disposition of emphysema and how it cause emphysema ?
alpha antitrypsin deficiency
- inability to breakdown elastase
- too much elastase in the blood
- elastase breakdown elastin
- without elastin, the lungs looses its elasticity
what is the environmental factors of emphysema and how it cause emphysema ?
tobaccoo smoke and air pollution
- triggers inflammatory response
- increase the number of neutrophils, microphases, elastase and protease
- neutrophils produces elastase
what is the role of elastin?
it allows the lungs to expand and recoil to allow the air in the lungs to be expelled
what happen when there is a breakdown of elastic tissue and collagen in the lungs ?
- air cannot be expelled easily and is trapped in the lungs
- there will be inflammation of bronchioles
- in smoke induced emphysema, the increased mucus secretion and inflammation in bronchioles will decrease airway clearance ability
what are the diagnostic test to test for emphysema?
- xray
- pulmonary function test (spirometry)
- abg
- ct scan
what is the xray results of emphysema?
- flattened diaphgram
- bilaterally hyperlucent lungs of large volume
- widened costophrenic angles and horizontal ribs
- narrow mediastinum
what does pulmonary function test of emphysema show?
- increased residual volume (IRV)
- increased total lung capacity (TLC)
what does abg results of emphysema shows?
decreased PaO2 and normal PaCo2 until later in the disease as it progresses
what are the complications of emphysema ?
- pneumothorax as bullae might be ruptured
- weight loss due to effort in work of breathing
what are the symptom of emphysema?
- sob , productive cough, wheezing, chest tightness
- barrel chest
- tachycardia
- decreased chest expansion
- muscle wasting
- pursed lips
- use of accessory muscles
- pink puffer (pink skin)
- nail clubbing
what is chronic bronchitis?
it is the chronic obstruction of major and small arteries due to excessive production of mucus.
inhalation of irritants causes mucus production
history of productive cough for at least 3 consecutive month in at least 2 years
what will happen to long term chronic bronchitis?
- hyperplasia of goblet cells and mucous glands
- scarring of lung tissues (due to chronic inflammation and swelling)
- ciliary damage (will lead to mucus being trapped within bronchi and bacteria proliferation will occur and lead to pneumonia infection)
chronic bronchitis typically happen in
- patients that are overweight and in 30-40s
- more often in male(2:1)
GOLD class for copd
what are the diagnostic test for chronic bronchitis?
- xray
- pulmoary function test
- abg
- full blood count
xray results of chronic bronchitis
- not specific, need to correlate to signs and symptoms
- increased bronchovascular markings (start from the center)
- cardiomegaly (the pressure in the arteries of the lungs becomes very high, causing a back up of pressure on the right side of the heart as it sends blood to the lungs)
what is the result of pulmonary function test of chronic bronchitis?
- increase in residual volume (RV)
- FVC and FEV are decreased
what is the result of abg test for chronic bronchitis?
- decreased PaO2
- normal/ increased PaCO2
what is the full blood count test for chronic bronchitis ?
haematocrit over 50%, (polycythemia)
what are the symptoms of chronic bronchitis?
main ones are productive cough, cracklings due to phlegm
fev1 less than 70%
what are the complications of chronic bronchitis?
- pulmonary hypertension due to vasoconstriction from hypoxemia
- cor pulmonale (left side of the heart to fail dur to pulmonary hypertension)
- secondary polycythemia due to hypoxemia
what is pneumonia?
medical condition where lung tissue becomes inflamed
what are the symptoms of pneumonia ?
- crackles (rales) eating chips
- chills
- fever
- cough, purulent sputum
what are the diagnostic test of pneumonia?
- xray
- sputum culture and sensitivity test
what does pneumonia x ray show
- white spots in lungs (infiltrate shows infection)
- does not follow bronchovascular markings
does abg play a role in diagnosis of copd?
no, it only measures the severity of COPD
