A 50-year-old male presents with sudden hematemesis (4 episodes, ~1200ml total) and melena (2 episodes, ~600g total), accompanied by dizziness and palpitations. On examination: BP 75/45 mmHg, heart rate 118 bpm, mild icterus of the sclera, abdominal distension, liver not palpable, spleen palpable 3 cm below the costal margin, shifting dullness (+). What is the first-line management for this patient?