Review Question - QID 216270

A 52-year-old man presents to the emergency department by ambulance for evaluation of hematemesis. His wife states that he began vomiting bright red blood this evening while eating dinner, and has produced about 5 cups total. He has a history of alcohol use disorder and has vomited small streaks of blood in the past, but has never undergone formal medical workup for it. On exam, he has bright red blood in his mouth and pharynx, and also displays a distended abdomen with a fluid wave, jaundice, scattered spider angiomas, and multiple ecchymoses. His temperature is 98.4°F (36.9°C), blood pressure is 98/68 mmHg, pulse is 125/min, and respirations are 22/min. A rapid point-of-care hemoglobin and platelet count is 8.8 g/dL and 80,000/mm^3, respectively. The patient is given 1L of normal saline. Which of the following is the most appropriate initial step in management?