Pursed-lip breathing is a classic compensatory mechanism seen in patients with emphysema, a form of chronic obstructive pulmonary disease (COPD). According to NREMT education, emphysema is characterized by destruction of the alveolar walls, which leads to loss of lung elasticity. This loss prevents the small airways from remaining open during exhalation.
Option A is correct because pursed-lip breathing creates positive pressure in the airways during exhalation. This pressure helps keep collapsed airways open longer, allowing trapped air to escape and improving ventilation. It also reduces the work of breathing and helps alleviate dyspnea.
Option B is incorrect because decreased hemoglobin affects oxygen-carrying capacity, not airway mechanics or breathing patterns.
Option C is more commonly associated with chronic bronchitis, not emphysema.
Option D is incorrect because diaphragmatic dysfunction is not the primary cause of pursed-lip breathing.
NREMT emphasizes recognizing compensatory breathing patterns in chronic lung disease to guide supportive care, including oxygen administration and positioning.
