A nurse is caring for a patient with portal hypertension who suddenly develops signs of respiratory distress, dizziness, and increasing restlessness after coughing up blood tinged sputum. Which nursing action should be prioritized to address the most likely complication?

Administer diuretics immediately to reduce portal vein pressure and prevent worsening complications.

Prepare to administer intravenous vasopressors to manage blood pressure.

Initiate oxygen therapy and monitor arterial blood gases to manage hypoxia from ascites.

Assess for signs of esophageal variceal bleeding and prepare for emergency endoscopic intervention.