Bronkospazma

Bronkospazma, or bronchospasm, is a sudden constriction of the bronchial smooth muscles that narrows the airways and causes wheezing and breathing difficulty. It is a feature of asthma, chronic obstructive pulmonary disease (COPD), bronchitis, anaphylaxis, allergic reactions, and other conditions. The underlying mechanism involves airway smooth muscle contraction, bronchial hyperresponsiveness, inflammation, and increased mucus production. Triggers include allergens (pollen, animal dander), irritants (tobacco smoke, air pollution), cold air, exercise, respiratory infections, and certain medications such as nonselective beta-blockers.

Symptoms include wheezing, shortness of breath, chest tightness, coughing, and rapid breathing. The onset may be gradual or sudden and can be more severe at night or with exertion.

Diagnosis relies on clinical history and lung function testing. Spirometry showing reduced FEV1 and FEV1/FVC ratio that improves after administration of a bronchodilator supports the diagnosis. Peak expiratory flow monitoring may be used in asthma or COPD. In uncertain cases, bronchoprovocation tests (eg, methacholine challenge) can be used.

Management depends on severity. Acute bronchospasm is treated with inhaled short-acting beta-agonists (eg, albuterol) and, if needed, systemic corticosteroids, oxygen therapy, and monitoring. In severe or life-threatening cases, intravenous magnesium sulfate or epinephrine may be required. Long-term control includes avoiding triggers and anti-inflammatory controller medications such as inhaled corticosteroids; long-acting beta-agonists or combination therapy; leukotriene modifiers. In exercise-induced bronchospasm, pre-exercise inhalers or warm-up strategies can help.

Prognosis varies with the underlying condition; bronkospazma is often reversible with prompt treatment, but recurrent episodes indicate chronic airway disease that requires ongoing management.