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Definition

Asthma is a chronic inflammatory disease of the airways that makes them hyper-responsive, so they narrow in reversible attacks.

Mechanism

• Inflammation and swelling of the airway lining
• Contraction of the smooth muscle around the airways (bronchospasm)
• Excess thick mucus

Triggers

Dust, mites, animal dander, smoke, cold air, exercise, viral infections, and some drugs such as aspirin and non-selective beta-blockers.

Symptoms

• Wheeze, clearest on expiration
• Breathlessness and chest tightness
• Cough worse at night and early morning

Diagnosis

Spirometry with FEV1 improving by 12% or more after a bronchodilator, plus peak flow monitoring.

Treatment

• Reliever: short-acting bronchodilator such as salbutamol
• Preventer: inhaled corticosteroid (ICS), adding a long-acting bronchodilator by severity
• Severe attack: oxygen, nebulised salbutamol and ipratropium, systemic steroid

Nursing care

• High Fowler’s position; monitor SpO2 and respiratory rate
• Teach inhaler technique with a spacer, and mouth rinsing after steroids

Exam point

A silent chest in a severe attack is very dangerous: it means air is barely moving, not that the patient is improving.