A 28-year-old female patient has been admitted with fever, chills and rigors. She also has a productive cough and pleuritic chest pains. She has been recently diagnosed with asthma. She smokes 5–10 cigarettes a day. She works in a bakery and describes symptoms of rhinorrhoea and wheezing while at work and after work. She has been prescribed an inhaler by her GP, but has not been compliant. On examination her temperature is 38°C and respiratory rate 20. Her oxygen saturation is 88% on room air. There are diffuse polyphonic wheezes in the lung fields, with bronchial breath sounds in the left mid to lower zone. Her sputum mug shows rusty purulent sputum.
Approach to the patient
Symptoms of chronic cough, especially nocturnal cough, wheezing and complaints of chest tightness, can be clues to consider asthma in the list of differential diagnoses in the dyspnoeic patient. In the known asthmatic, there are some questions that should invariably be asked.
Ask about:
• the current asthma management regimen, and frequency of bronchodilator use. Check whether the patient is using a bronchodilator at an unusually high frequency.
• what the known precipitants of asthma attacks are and how often the patient experiences exacerbations
• whether the patient has ever been hospitalised or treated in the intensive care unit for exacerbation of asthma
• whether the patient has a nocturnal cough
• whether the patient monitors their airway function with a peak flow meter at home. If they do monitor the peak flow, ask how often it is performed and the usual and most recent readings.
• the variability of the peak flow meter readings before and after bronchodilator therapy. Persistent variability is indicative of poor disease control.
• seasonal variation of symptoms and association with exercise
• whether an allergist has been consulted or special tests for allergy (skin prick test and radioallergosorbent (RAST) test) have been performed
• corticosteroid use—how often the patient is prescribed oral steroids, the maximum dose and the minimum dose ever, and the side-effect profile the patient has experienced
• how this chronic condition has affected the patient’s day-to-day life and occupational activities.
Drugs used in asthma
Asthma medications are broadly classified into two categories based on their clinical effects. The first category is the group of medications that improve symptoms (relievers) and the second category prevent exacerbations (preventers).
• Relievers—are short-acting beta2 agonists such as salbutamol, terbutaline, and long-acting beta2 agonists such as efemetorol. Tiotropium and ipratropium bromide are inhaled anticholinergic bronchodilator agents with a slower onset of action. Theophylline, which is capable of relaxing bronchial smooth muscle, is also used to treat severe and acute exacerbations of asthma. However, due to its wide adverse effects profile (nausea, diarrhoea, arrhythmias) it is rarely used these days.
• Preventers—include inhaled corticosteroids such as beclomethasone, budesonide, fluticasone and ciclesonide. Other preventers are leukotriene receptor blockers (montelukast) and cromoglycates (mast cell stabilisers).
– Inhaled corticosteroids have proven benefits in reducing exacerbations, reducing mortality and recurrent hospital admissions. These agents are known to improve overall quality of life in chronic asthmatics. However, long-term high-dose therapy with topical corticosteroids can bring about systemic adverse effects such as cataracts, osteoporosis, glaucoma and cutaneous fragility.
– Leukotriene inhibitors such as montelukast have particular use in the treatment of aspirin-induced asthma and in preventing exercise-induced asthma. They can be combined with inhaled steroids when adequate control is not achieved with single-agent therapy.
– Cromones such as nedocromil sodium and sodium cromoglycate are capable of preventing early and late bronchoconstrictor reactions to allergen exposure and therefore have particular use in seasonal allergic asthma. They have shown benefit in the prevention of exercise-induced asthma. Nedocromil is useful in the treatment of asthma-associated cough.
