What is a common airway and respiratory response to cold, dry air exposure?

• A. Increased ventilation to meet metabolic demands; cold air can irritate airways, potentially causing bronchoconstriction in susceptible individuals
• B. Decreased ventilation
• C. Bronchodilation in all individuals
• D. No change

Answer: (A)

Cold, dry air challenges the airway by demanding extra work to warm and humidify the inspired air, which tends to increase ventilation. At the same time, the cold, dry air can irritate the airway mucosa and activate sensory receptors, triggering a reflex bronchoconstriction in susceptible individuals (such as those with asthma or exercise-induced bronchoconstriction). This combination explains why the typical response includes higher ventilation with a potential narrowing of airways in sensitive people. The other options don’t fit: ventilation isn’t typically decreased; bronchodilation doesn’t occur universally with cold air; and there is usually some change in airway behavior, not no change.