Review Question - QID 108736

A 16-year-old boy is brought to the emergency department after being struck by a moving vehicle. The patient reports that he was running through his neighborhood when a car struck him while turning right on a red light. He denies any loss of consciousness. His temperature is 37.2°C (99.0°F), blood pressure is 88/56 mmHg, pulse is 121/min, respirations are 12/min, and SpO2 is 95% on room air. The patient is alert and oriented to person, place and time and is complaining of pain in his abdomen. His lungs are clear to auscultation bilaterally and on cardiac exam, he is tachycardic with normal S1 and S2. His abdomen is soft, but diffusely tender to palpation. The patient tenses his abdomen when an abdominal exam is performed. He is moving all 4 extremities spontaneously. His skin is cool with delayed capillary refill. After the primary survey, 2 large-bore IVs are placed, and the patient is given a bolus of 2 liters of normal saline. Which of the following is the most appropriate next step in management?