A 23-year-old man presents with fever on postoperative day 6 after undergoing total colectomy for colon polyps. On examination, he has right leg swelling and a positive Homan's sign. Doppler ultrasound is recommended to diagnose deep vein thrombosis (DVT), which is a common cause of fever at this postoperative time due to immobility risk. Risk factors for DVT include recent surgery and refusal of prophylactic heparin.