Spirometry and Lung Volumes

A 28-year-old woman with a history of asthma presents with episodic wheezing and dyspnea. Her baseline spirometry shows FEV₁/FVC ratio of 0.82 with normal absolute values. During an acute exacerbation, she reports worsening dyspnea. Which investigation is most appropriate to assess the degree of airway obstruction during the acute episode?

A patient's spirometry shows FVC = 3.5 L, FEV₁ = 2.8 L, and FEV₁/FVC ratio = 80%. Which pattern does this represent?

A 58-year-old male smoker presents to the pulmonology clinic with progressive dyspnea on exertion for 6 months. He denies fever, hemoptysis, or chest pain. Examination reveals decreased breath sounds bilaterally and prolonged expiratory phase. Spirometry shows: FEV₁ = 52% predicted, FVC = 78% predicted, FEV₁/FVC ratio = 0.58. TLC = 125% predicted, RV = 180% predicted. What is the primary pattern of pulmonary dysfunction demonstrated by these findings?

A 52-year-old man with chronic obstructive pulmonary disease (COPD) undergoes spirometry. All of the following findings are consistent with COPD EXCEPT:

A 52-year-old man with a 30 pack-year smoking history presents with progressive dyspnea on exertion and chronic cough. Physical examination reveals decreased breath sounds bilaterally. Chest X-ray shows hyperinflation with flattened diaphragms. Which investigation is most appropriate to confirm the diagnosis and assess the severity of airflow obstruction?