A 68-year-old woman is admitted to the hospital with an acute exacerbation of chronic obstructive lung disease. She is intubated for worsening hypercarbia and transferred to the medical ICU. On day 8 of her ICU stay, she is felt to be clinically improving and close to extubation readiness when she develops intermittent desaturation and increased tracheal secretions. A portable chest radiograph demonstrates a new right lower lobe infiltrate. A tracheal aspiration is obtained for culture.
Which of the following would be appropriate intravenous antibiotic regimen?A. Metronidazole
Correct Answer: C
The patient has developed a ventilator-associated pneumonia (VAP), as defined by new worsening respiratory status, worsening volume and quality of sputum, and new radiographic infiltrate. VAPs frequently occur because of aspiration of secretions around the cuff of an endotracheal tube. Nosocomial pathogens, including P. aeruginosa and methicillinresistant S. aureus, are common causes of VAP. Empiric coverage for these pathogens with an antipseudomonal beta-lactam and vancomycin is therefore recommended while awaiting culture results; choice of an antipseudomonal agent may depend on local resistance patterns (answer C is correct; answer D is incorrect). Treatment with ceftriaxone is inadequate as is does not provide coverage of Pseudomonas or methicillin-resistant S. aureus. Azithromycin is important when considering treatment of atypical organisms, particularly Legionella in community-acquired pneumonia, but would not be necessary for empiric VAP coverage (answer B and E are incorrect). Metronidazole adds additional anerobic coverage, which is not considered necessary in the treatment of VAP (answer A is incorrect).