Asthma Flashcards
Describe asthma. (6)
Chronic inflammatory airways disease characterised by intermittent, spontaneous and reversible airway obstruction and hyper-reactivity. A disease of the small airways with various expiratory airflow limitation.
Describe the pathophysiology of asthma. (6:
Basically bronchoconstriction and inflammation cause narrowed small airways.
Initially a type 1 hypersensitivity reaction causing a release of histamine, and leukotrienes from mast cells.
Constriction of airways smooth muscle.
Mucus hypersecretion
Inflammation.
Describe the signs and symptoms of asthma. (5)
Dry cough, possibly nocturnal, expiratory wheeze, breathlessness, chest tightness.
Describe precipitating factors of asthma. (5)
Allergens (dust, pollen), cigarette smoke, cold weather, exercise, infection, aerosols.
Describe examination of a patient with asthma. (4)
Resp rate raised
Bilateral wheeze
Lowered oxygen sats
Atopy - eczema, hay fever.
Describe investigations of asthma. (2)
Peak flow meter
Spirometry - scalloping, reduced FEV1 : FVC ratio
Explain the differences between asthma and COPD. (5)
Asthma : dry cough, history of atopy, generally reversible with bronchodilator, day to day variability, worse at night
COPD: productive cough, history of smoking, not reversible, no day to day variability, not worse at night.
Explain the similarities between asthma and COPD. (2)
Both obstructive lung disease that presents with wheeze.
Describe the management of chronic asthma. (4)
Remove triggers Pharmacology: - short acting beta 2 agonists - blue - long acting beta 2 agonists - green - inhaled corticosteroid - brown
Explain how beta 2 agonists work in relieving the symptoms of asthma. (4)
Stimulates G alpha S
Produces cAMP
Activates PKA
Causes bronchodilation.
Describe acute management of asthma. (4)
Oxygen
Short acting beta 2 agonists through nebuliser
Steroids
Admit - consider CXR
Describe the consequences of severe prolonged acute asthma attack. (4)
Respiratory alkalosis
Hypoxia
Type 1 Resp failure
Type 2 Resp failure