A 75-year-old man is seen preoperatively before a

A 75-year-old man is seen preoperatively before a nephrectomy for renal cell carcinoma. He has a history of chronic obstructive pulmonary disease (COPD) due to smoking, and he has had multiple unsuccessful attempts at smoking cessation. He currently smokes about 15 cigarettes daily. He has a chronic cough but denies having dyspnea, and he walks 2 to 3 miles daily without symptoms. He has no other medical problems. He has had 2 exacerbations of COPD in the past 2 years, during which he was treated as an outpatient and did not require systemic corticosteroids. What is the best way to manage him preoperatively? a. Perform spirometry and check arterial blood gases. b. Perform chest radiography, spirometry, and a 6-minute walk test. c. Perform spirometry and check lung volumes. d. No further testing is needed. e. Delay his surgery for 8 weeks until he has stopped smoking.