Review Question - QID 109530

A 45-year-old man is brought to the emergency department by police. He was found passed out in a store. The patient is dressed in soiled clothing that smells of urine and his pants are soaked in vomit. The patient has a past medical history of IV drug use, alcohol use, and multiple fractures secondary to scurvy. He is not currently taking any medications. His temperature is 99.5°F (37.5°C), blood pressure is 90/63 mmHg, pulse is 130/min, respirations are 15/min, and oxygen saturation is 95% on room air. The patient is started on IV fluids, thiamine, and dextrose. The patient becomes arousable at this point and begins vomiting into a basin. On physical exam, the patient appears uncomfortable. His epigastric region is tender upon palpation. A cardiac exam reveals a normal rate and rhythm. A pulmonary exam is clear to auscultation bilaterally. A CT scan of the abdomen is ordered as seen in Figure A. Laboratory values are ordered as seen below:

Serum:
Na+: 139 mEq/L
Cl-: 102 mEq/L
K+: 4.0 mEq/L
HCO3-: 26 mEq/L
BUN: 20 mg/dL
Glucose: 73 mg/dL
Creatinine: 1.1 mg/dL
Ca2+: 10.2 mg/dL
Lipase: 295 U/L
AST: 57 U/L
ALT: 39 U/L

Hemoglobin: 9 g/dL
Hematocrit: 30%
Mean corpuscular volume: 120 µm^3
Leukocyte count: 8,500/mm^3 with normal differential
Platelet count: 199,000/mm^3

The patient continues to vomit and is observed in the emergency department. Several hours later his temperature is 99.5°F (37.5°C), blood pressure is 110/72 mmHg, pulse is 97/min, respirations are 15/min, and oxygen saturation is 95% on room air. Physical exam reveals a cardiac and pulmonary exam that are within normal limits. HEENT exam reveals suprasternal crepitus, an oropharynx that is blood-stained, and no signs of lymphadenopathy. Inspection of the patient’s lower extremities is within normal limits. Which of the following is the most appropriate next step in management?