Q. A 55-year-old man with a smoking history presents to the emergency department with a complaint of hemoptysis. The patient reports coughing up small amounts of blood for the past week. He also has fatigue and feels lethargic. On physical examination, he appears well, is afebrile, and has no signs of distress. Vital signs report blood pressure 140/90 mmHg, pulse 70 beats per minute, respiratory rate 18 breaths per minute, and oxygen saturation 98% on room air. Lung examination reveals no rales, wheezes, or rubs. Laboratory tests reveal hemoglobin of 13.4 g/dL, hematocrit of 39%, white blood cell count of 7,500/?L, and platelet count of 250,000/?L. A chest x-ray shows a normal lung field with no focal infiltrates. Which of the following is the most appropriate next step in management?