bronkospasm

Bronchospasm, sometimes spelled bronkospasm in some languages, is a sudden tightening of the muscles around the airways in the lungs, causing narrowing of the bronchi and bronchioles and reduced airflow. It is most often associated with asthma, but can occur in chronic obstructive pulmonary disease, allergic reactions, respiratory infections, drug reactions, and during intense exercise.

Pathophysiology involves contraction of airway smooth muscle, airway edema, and increased mucus production, driven by inflammatory mediators such as histamine, leukotrienes, and prostaglandins. Autonomic nervous system imbalances, particularly increased parasympathetic tone or heightened airway hyperreactivity, contribute to the response. Triggers include allergens, cold air, exercise, viral infections, smoke or pollution, and certain medications (for example, aspirin or other NSAIDs in sensitive individuals).

Symptoms typically include wheezing, coughing, shortness of breath, chest tightness, and audible difficulty with expiration. On examination, there may be use of accessory muscles and prolonged expiration. Diagnosis is largely clinical and supported by spirometry showing reduced expiratory flow (low FEV1) with partial or near-full reversal after administration of a bronchodilator. Peak expiratory flow monitoring can be used to track stability at home.

Management depends on severity and underlying cause. Rapid-acting bronchodilators (short-acting beta-agonists such as albuterol) are first-line for acute episodes. Anticholinergic inhalers may be used, and systemic corticosteroids are often required for more severe attacks. Long-term control in asthma or COPD includes inhaled corticosteroids, long-acting bronchodilators, and trigger avoidance. In emergencies, supplemental oxygen and medical supervision are essential; epinephrine is used for anaphylaxis.

Prognosis varies with the underlying condition and prompt treatment. Most episodes resolve with therapy, but recurrent bronchospasm requires ongoing management of the underlying disease and avoidance of triggers.