ASTHMA
Definition
Asthma is a chronic inflammatory disorder of the airways in which many cells and cellular elements play a role; in particular, mast cells, eosinophils, T lymphocytes, macrophages, neutrophils, and epithelial cells. In susceptible individuals, this inflammation causes recurrent episodes of wheezing, breathlessness, chest tightness and coughing, particularly at night or in the early morning. These episodes are usually associated with widespread but variable airflow obstruction that is often reversible either spontaneously or with treatment. The inflammation also causes an associated increase in the existing bronchial responsiveness to a variety of stimuli. Asthma symptoms are characteristically worse during sleep and may be intensified by emotion.
Aetiology / Risk Factors
Hypersensitivity to aeroallergens (including dust mites; cockroaches; dog, cat, or other animal proteins; fungal spores; pollens; dusts; and fumes)
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Exercise
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Respiratory infections
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Exposure to cold or dry air
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Air pollutants, such as tobacco, aerosols, perfumes, fresh newsprint, diesel particles, sulphur dioxide, elevated ozone levels, and fumes from chemical-cleaning agents and gas stoves
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Meteorological changes in temperature and humidity
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Emotional behaviours that alter breathing such as laughing, shouting, or crying
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Gastroesophageal reflux
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Aspirin, non-steroidal anti-inflammatories (NSAIDs) and beta blockers
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Family history of allergies or asthma
Symptoms & Signs
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Shortness of breath or dyspnoea
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Wheezing
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Chest tightness or constriction
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Cough (can be the only symptom)
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Cyanosis
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Accessory muscle use
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Flattened diaphragm and hyper-inflated chest