Asthma management

Asthma and its management

It is a chronic reversible obstructive inflammatory airways disease in which many cells and cellular elements play a role by constriction of bronchial smooth muscle causing bronchospasm, oedema of bronchial mucous membrane and blockage of the smaller bronchi with plugs of mucous.

Clinical presentation

• Wheeze

• Shortness of breath

• Chest tightness

• Cough, particularly at night or in the early morning

• Tachypnea

• Tachycardia

• Diffuse musical wheezes

• Prolonged phase of exhalation

• Chest hyperinflation

• Use of accessory muscles

Investigations

• FBP (look for eosinophilia)

• Serum IgE

• ESR

• ABG

• CXR if highly suspicious of pneumonia

• Sputum for cytology (look for eosinophilia)

• Lung function tests (e.g., spirometry with reversibility test, PEFR measurement with a peak flow meter)

• Exhaled NO should be done to assess evidence of variable expiratory airflow limitation

Non-pharmacological treatment

• Avoid polluted environments (both indoors and outdoors)

• Avoid non-selective β-blockers, which can trigger asthmatic attacks

• Avoid heavy exercise

• Stop smoking

• Avoid both overweight and underweight

Assessment and treatment of asthma attack in children ≥2 years and adults

Mild-moderate attack

Clinical presentation

• Able to talk in sentences or phrases

• Not agitated

• Pulse rate 100–120 bpm

• SpO₂ (on air) 90–95%

• PEF >50% predicted

Treatment

Salbutamol inhalation

(Can be given by pMDI, spacer, or nebulization)

Give:

• 4–10 puffs by pMDI/spacer every 20 minutes for the first hour

Or

• Salbutamol (nebulization):

  • Adults: Salbutamol respules 5 mg 6 hourly (2–3 cycles and reassess)

  • Paediatrics: 2.5 mg 6 hourly (2–3 cycles and reassess)

If symptoms completely subside:

• Observe for 1–4 hours

• Give salbutamol for 24–48 hours (2–4 puffs every 4–6 hours) for 3 days

If attack is only partially resolved:

• 2–4 puffs of salbutamol every 3–4 hours if attack is mild

• 6 puffs every 1–2 hours if attack is moderate

Continue until symptoms subside.

When attack completely resolves, proceed as above.

Prednisolone

• Prednisolone (PO):

  • Adults: 40 mg mane for 7 days

  • Paediatrics: 1–2 mg/kg (maximum 40 mg)

Do tapering if treatment exceeds seven days.

Controlled oxygen

• If available, target oxygen saturation:

  • Adults: 93–95%

  • Children: 94–98%

Severe attack

Clinical presentation

• Talks in words only

• Cannot complete a sentence in one breath or too breathless to talk/feed

• Sits hunched forwards

• Agitated

• Respiratory rate >30/min

• Accessory muscles being used

• Pulse rate >120 bpm

• O₂ saturation (on air) <90%

• PEF ≤50% predicted or best

Treatment

General measures

• Admit the patient

• Place in semi-sitting position

Oxygen therapy

• Oxygen continuously at 5 L/min

• Maintain oxygen saturation:

  • Adults: 93–95%

  • Children: 94–98%

Bronchodilator therapy

• Salbutamol inhalation:

  • 4–10 puffs every 20–30 minutes in children <5 years

  • Up to 20 puffs in children >5 years and adults

Add:

• Ipratropium bromide (inhalation) 0.25–0.5 mg every 6–8 hours

Corticosteroid therapy

• Hydrocortisone (IV):

  • Children: 5 mg/kg

  • Adults: 100 mg every 6 hours

Then switch to:

• Prednisolone (PO):

  • 1–2 mg/kg every 24 hours

  • Complete 7 days of treatment

If attack is completely resolved:

• Continue salbutamol inhalation 2–4 puffs every 4 hours for 24–48 hours

• Continue oral prednisolone 1–2 mg/kg every 24 hours to complete 3–5 days of treatment

If not improving or condition worsens, treat as life-threatening attack.

Life-threatening attack

Clinical presentation

• Altered level of consciousness (drowsiness, confusion, coma)

• Exhaustion

• Silent chest

• Paradoxical thoracoabdominal movement

• Cyanosis

• Collapse

• Bradycardia in children

• Arrhythmia or hypotension in adults

• O₂ saturation <92%

Treatment

General measures

• Admit the patient

• Place in semi-sitting position

Oxygen therapy

• Oxygen continuously at 5 L/min

• Maintain oxygen saturation between 94–98%

Bronchodilator therapy

• Salbutamol (nebulization):

  • Children <5 years: 2.5 mg

  • Children >5 years and adults: 2.5–5 mg every 20–30 minutes

Then switch to salbutamol aerosol when clinical improvement is achieved.

Add:

• Ipratropium bromide (inhalation) 0.25–0.5 mg every 6–8 hours

Corticosteroid therapy

• Hydrocortisone (IV):

  • Children: 5 mg/kg

  • Adults: 100 mg every 6 hours

Then switch to:

• Prednisolone (PO):

  • 1–2 mg/kg every 24 hours

  • Complete 7 days of treatment

Additional therapy in adults

• Magnesium sulphate:

  • Infusion of 1–2 g in 0.9% Sodium Chloride over 20 minutes