Chronic bronchitis

Chronic bronchitis

Chronic bronchitis is defined by a chronic productive cough for three months in each of two successive years in a patient in whom other causes of chronic cough have been excluded.

Patients may develop secondary bacterial infection with fever and production of thick, foul-smelling sputum.

Risk factors for chronic bronchitis

1. Cigarette smoking

2. Indoor air pollution

• Exposure from burning wood

• Exposure to biomass fuel

• Heating in poorly ventilated dwellings

3. Occupational exposure

• Coal miners

• Tunnel workers

• Hard-rock miners

• Concrete manufacturing workers

• Livestock farming (e.g. exposure to pesticides)

4. Exposure to agricultural pollutants

5. Use of domestic solid fuel

Investigations

As in acute bronchitis.

Non-pharmacological treatment

• Stop smoking (reduces loss of lung function) and/or remove the patient from a hazardous environment.

• Prompt treatment of infective exacerbations.

• Controlled oxygen therapy.

• Physiotherapy.

• Pulmonary rehabilitation, consisting of:

  • Education

  • Lifestyle modification

  • Regular physical activities

  • Physiotherapy

  • Avoidance of indoor and outdoor pollutants

• Nutritional support.

• BiPAP in specialized centres.

• Influenza vaccine in specialized centres.

Pharmacological treatment

Pharmacological therapy for chronic bronchitis is directed towards three major goals:

Relieving symptoms during stable disease

Mucoactive agents

• Reduce overproduction and hypersecretion.

• Increase mucus elimination.

For pharmaceutical management, refer to the Emergency and Critical Care chapter.

Hypertonic saline

• Stimulates productive cough.

• Decreases sputum viscoelasticity.

• Increases mucociliary clearance.

Dosage:

• 7% hypertonic saline or 0.9% saline twice daily PRN.

Bronchodilators (beta-agonists)

• Promote mucus clearance by increasing airway luminal diameter and ciliary beat frequency.

• Reduce hyperinflation.

• Improve peak expiratory flow (PEF).

Short-acting beta-agonists (SABA)

• Salbutamol (inhalation) 100 mcg, 2 puffs every 6 hours.

OR

Long-acting beta-agonists (LABA)

• Salmeterol + fluticasone

• Or in combination with steroids (salmeterol + fluticasone or budesonide + fluticasone)

Muscarinic antagonists

• Decrease contractility of smooth muscle in the lung.

• Inhibit bronchoconstriction and mucus secretion.

Short-acting muscarinic antagonists (SAMA)

• Ipratropium bromide (aerosol) 20–80 mcg every 6–8 hours.

Long-acting muscarinic antagonists (LAMA)

• Tiotropium (mist inhaler) 6 mcg, 2 puffs every 24 hours.

Preventing exacerbations

Mucoactive agents

• Refer to the cough section.

Macrolides (as indicated)

Effects:

• Antibacterial effects

• Immunomodulatory effects

• Anti-inflammatory effects

Examples:

• Azithromycin

• Clarithromycin