Question

A $58$-year-old man with a history of alcohol use disorder and cirrhosis is brought to the emergency department by his family due to a $2$-day history of diffuse abdominal pain, subjective fever, and worsening confusion. He also complains of mild shortness of breath. His temperature is $38.3^\circ\text{C}$ ($100.9^\circ\text{F}$), pulse is $105/\text{min}$, blood pressure is $105/65\text{ mmHg}$, and respirations are $18/\text{min}$. Physical examination reveals scleral icterus and spider angiomas on the chest. The abdomen is prominently distended with shifting dullness and diffuse mild tenderness, but there is no rebound or guarding. Neurologic examination demonstrates a bilateral flapping tremor when the arms are extended. A diagnostic paracentesis yields cloudy fluid. Ascitic fluid analysis shows a leukocyte count of $650/\text{mm}^3$ with $85\%$ neutrophils, and a total protein of $0.8\text{ g/dL}$. Serum creatinine is $1.3\text{ mg/dL}$. Which of the following is the most appropriate next step in management?