Asthma

Definition and triggers

Asthma is a chronic inflammatory airway disorder with airway hyperresponsiveness. It causes recurrent wheezing, breathlessness, chest tightness, and cough, usually with variable airflow obstruction that may improve spontaneously or with treatment.

Common precipitating or aggravating factors include allergens, respiratory infection, exercise, tobacco smoke, air pollution, and medicines such as aspirin.

Symptoms may worsen at night. In children up to 5 years, early asthma-like episodes often occur with respiratory infections and may become less frequent over time rather than progressing to chronic asthma.

Acute asthma severity

• An asthma attack is a substantial worsening of symptoms. Severity and duration are variable and can be unpredictable.
• Assess severity rapidly and repeatedly; not all signs are present in every patient.
• For all attacks, look for underlying lung infection and treat it when present.

Mild or moderate attack treatment

• Reassure the patient and place in a half-sitting position.
• Give salbutamol MDI 100 micrograms/puff: 2 to 10 puffs every 20 minutes during the first hour. Use a spacer in children, with a face mask for children under 3 years.
• Give single puffs one at a time and allow the child to breathe 4 to 5 times from the spacer before giving the next puff. Adults may also benefit from a spacer.
• Give prednisolone PO 1 to 2 mg/kg once, maximum 50 mg, for children over 5 years and adults.
• Give oxygen if SpO2 is below 94%. If pulse oximetry is unavailable, give continuous oxygen for moderate, severe, or life-threatening attacks.

Response after initial treatment

• Reassess after 1 to 2 days. Address risk factors, reassess need for salbutamol, and evaluate long-term treatment.
• If the patient already uses controller treatment, review severity, adherence, inhaler technique, and need for treatment adjustment.

Severe attack treatment

• Hospitalise; transfer life-threatening attacks to intensive care as soon as possible.
• Place in a half-sitting position and give oxygen to maintain SpO2 between 94% and 98%.
• Give salbutamol plus ipratropium by nebuliser every 20 minutes for the first hour while continuing oxygen by nasal cannula during nebulisation. Mix the solutions in the nebuliser reservoir and reassess after each nebulisation.
• If no nebuliser is available, use salbutamol MDI as for mild/moderate attacks plus ipratropium MDI 20 micrograms/puff, 4 to 8 puffs every 20 minutes for the first hour.
• Give prednisolone PO 1 to 2 mg/kg once, maximum 50 mg. If prednisolone is unavailable or oral treatment cannot be taken, use dexamethasone in children or hydrocortisone IV in adults according to local protocol.

Chronic asthma diagnosis

• Suspect asthma with recurrent wheeze, chest tightness, shortness of breath, or cough of variable frequency, severity, and duration, especially when symptoms disturb sleep, make the patient sit up to breathe, or occur during or after exercise.
• Auscultation may be normal or may show diffuse wheeze.
• Personal or family history of eczema, allergic rhinitis, allergic conjunctivitis, or asthma increases probability but absence of atopy does not exclude asthma.
• Consider asthma after excluding other diagnoses in a patient with typical symptoms and characteristic history.
• Eliminate or reduce identified risk factors such as allergens, pollution, and tobacco smoke exposure wherever possible.

Long-term treatment principles

Long-term treatment is based on inhaled corticosteroids and long-acting beta-2 agonists. A long-acting beta-2 agonist must not be used alone; it should always be paired with an inhaled corticosteroid, preferably in a combination inhaler when available.

• Start at the step that matches initial severity, then re-evaluate and adjust according to response.
• A severe attack or loss of control requires treatment reassessment.
• Choose inhaler device by age. Children should use a spacer. Teach inhaler technique and explain attack symptoms.
• Use the lowest effective inhaled corticosteroid dose that controls symptoms while limiting local and systemic adverse effects.

Special situations and follow-up

• Do not restrict exercise. If exercise triggers attacks, give 1 or 2 puffs of salbutamol or beclometasone/formoterol 10 minutes before exercise.
• Pregnant patients are treated the same as adults during attacks. Oxygen in mild/moderate attacks reduces fetal hypoxia risk.
• Poorly controlled asthma in pregnancy increases risk of pre-eclampsia, eclampsia, haemorrhage, fetal growth restriction, preterm delivery, neonatal hypoxia, and perinatal mortality; continue long-term treatment with close monitoring.
• If symptoms are not controlled after 2 to 3 months, check inhaler technique and adherence before stepping up treatment.
• If symptoms are well controlled for at least 3 months, consider stepwise medication reduction.
• Handover should include severity signs, SpO2, reliever doses and response, steroid dose, oxygen, infection assessment, prior admissions, current controller regimen, inhaler technique, triggers, pregnancy status, and follow-up plan.