A 48-year-old male, hospitalized for 10 days following a motor vehicle accident and now receiving mechanical ventilation in the ICU, develops a new fever (102.5°F), purulent tracheal secretions, leukocytosis, and worsening oxygenation. A chest X-ray shows new bilateral infiltrates. Gram stain of tracheal aspirate shows numerous Gram-negative rods. What is the most appropriate empiric antibiotic regimen?
✓ Correct Answer: Option B
This patient has ventilator-associated pneumonia (VAP), a form of hospital-acquired pneumonia (HAP). Empiric therapy for VAP requires broad-spectrum coverage for both Gram-negative organisms (including Pseudomonas aeruginosa) and methicillin-resistant Staphylococcus aureus (MRSA). Piperacillin-tazobactam covers Pseudomonas and other Gram-negatives, while vancomycin covers MRSA.