A 55-year-old male with a known history of alcohol-related liver cirrhosis presents to the emergency department with altered mental status and a distended abdomen. His vital signs show a blood pressure of 90/60 mmHg, a heart rate of 110 beats per minute, and a respiratory rate of 22 breaths per minute. On examination, you notice asterixis and a firm, tender liver edge. Based on the patient's presentation, which of the following would be the most immediate intervention to perform?
Administer lactulose to reduce ammonia levels.
Prepare the patient for emergency liver transplantation.
Perform a paracentesis to remove ascitic fluid.
Immediately start broad-spectrum antibiotics.