Review Question - QID 215172

A 43-year-old man presents to the emergency department with bright red blood in his stool this morning. He noticed this yesterday as well, but it was much scanter. The patient is otherwise healthy. He was celebrating his birthday last night and admits having "too much to drink" and vomited profusely overnight. He currently feels well and is not nauseous. He has no other significant medical history and does not take any medications. His temperature is 99.2°F (37.3°C), blood pressure is 110/75 mmHg, pulse is 82/min, respirations are 16/min, and oxygen saturation is 100% on room air. Physical exam reveals a nontender abdomen with normal bowel sounds. Rectal exam reveals grossly bloody stool. Laboratory studies are ordered as shown below.
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