Question: A 72-year-old man with severe chronic obstructive pulmonary disease presents for follow-up evaluation and management. He is symptomatic at baseline, with dyspnea after one flight of stairs, and has a chronic cough and sputum production. His disease has been punctuated by exacerbations due to respiratory tract infection, leading to hospital admission between one and three times per year for each of the past several years. He was a long-standing smoker of 50 pack-years but is no longer smoking. On examination, his respiratory rate is 20/min, and his breathing pattern is notable for use of pursed lips during exhalation. Oxygen saturation at rest is 85%. Chest examination reveals decreased breath sounds, mild wheezing, and scattered rhonchi. Spirometry reveals severe airflow obstruction. Which of the following interventions has the greatest likelihood of improving the patient's survival? Supplemental oxygen for > 15 hours/day Low-dose oral corticosteroids Exercise rehabilitation Maintenance treatment with antibiotics Lung volume reduction surgery. Need Assignment Help?