Restrictive lung diseases Quiz: Ace Your Exams

A 62-year-old man presents with a worsening cough and shortness of breath for the past 5 months. He reports he used to be able to walk four blocks before becoming short of breath but now can only walk a half-a-block. He has a past medical history of hypertension and hyperlipidemia. He smokes 5-10 cigarettes per day and does not use alcohol or illicit substances. He has worked as a bird breeder for over 15 years. Temperature is 37°C (98.6°F), pulse is 62/min, respirations are 17/min, blood pressure is 138/94 mmHg, and oxygen saturation is 94% on room air. Physical examination is notable for a thin, cachectic male with coarse breath sounds bilaterally and digital clubbing. Chest CT scan is demonstrated below:  


^{Reproduced from: Radiopaedia}    
Lung biopsy is performed and reveals aggregates of epithelioid macrophages with multinucleated giant cells. This patient is most likely to demonstrate which of the following respiratory parameters?