A 50-year-old patient with a long history of emphysema suddenly develops acute shortness of breath and unilateral chest pain. A spontaneous pneumothorax is suspected. What is the most likely underlying pathophysiological cause?

A 44-year-old woman working as a cook has a 1-year history of episodic cough, wheezing, chest tightness, and dyspnea. Which pulmonary function test parameter is most critical to confirm the diagnosis of bronchial asthma by demonstrating reversible airway obstruction?

A 45-year-old client is admitted with an acute exacerbation of emphysema. Assessment shows fever, chills, productive cough, and shortness of breath on exertion. To help liquefy secretions and manage fever, what is a priority nursing action?