Bronchospasme

Bronchospasme, also known as bronchospasm, is a sudden constriction of the smooth muscle surrounding the bronchi, causing narrowing of the airways. This leads to wheezing, coughing, shortness of breath and chest tightness. The term is used in various languages, with bronchospasm being the common English equivalent.

Causes and pathophysiology

Bronchospasm occurs in conditions with airway hyperresponsiveness or inflammation, such as asthma, chronic obstructive pulmonary disease (COPD), allergic reactions, respiratory infections, exposure to irritants, and exercise-induced bronchospasm. The airway narrowing results from contraction of airway smooth muscle, increased mucus production, and airway edema, driven by inflammatory mediators. The combination raises airway resistance and impairs airflow primarily during expiration.

Clinical presentation and diagnosis

Patients typically report wheezing, dyspnea, coughing and chest tightness, with a rapid respiratory rate. In severe cases, breath sounds may be diminished, and there may be signs of respiratory distress. Diagnosis is primarily clinical, supported by spirometry showing reduced FEV1 and FEV1/FVC ratio, with partial or complete reversal after bronchodilator therapy. Peak expiratory flow measurements can aid assessment, particularly in outpatient settings. Oxygen saturation and clinical monitoring guide acute management.

Treatment and management

Acute treatment focuses on bronchodilation: inhaled short-acting beta-agonists (SABA) such as albuterol, often with an anticholinergic agent like ipratropium. Systemic corticosteroids may be used for persistent symptoms. Oxygen is provided as needed. In severe anaphylactic or life-threatening cases, additional interventions and emergency care are required. Long-term control of the underlying condition includes inhaled corticosteroids, long-acting bronchodilators, and trigger avoidance; exercise-induced bronchospasm may be mitigated with pre-exercise SABA.