Duration Matters: Tailoring Antibiotic Therapy for Ventilator-Associated Pneumonia

Ventilator-associated pneumonia (VAP) remains the most frequent ICU-acquired infection and a major driver of antimicrobial exposure. Historically, clinicians treated patients for 10-14 days or longer, particularly when multidrug-resistant organisms were suspected. Current evidence from randomized trials and meta-analyses now supports shorter-course therapy (~7 days) for most immunocompetent patients with VAP who demonstrate clinical improvement. Mortality and treatment failure are not increased when compared with longer regimes. The REGARD-VAP trial demonstrated the non-inferiority of individualized ≤7-day therapy compared with conventional longer courses. This remained true even in cohorts rich in non-fermenting Gram-negative bacilli (NF-GNB) and carbapenem-resistant organisms while markedly reducing antibiotic-related toxicity. North American and European guidelines recommend 7-8 days as the default duration, with individualized extension for slow clinical response, bacteremia, uncontrolled foci, or profound immunosuppression. Additionally, biomarker-guided discontinuation, particularly serial procalcitonin (PCT), may reduce antibiotic days when used to enrich clinical assessment. This narrative review synthesizes guideline recommendations, trial evidence, biomarker-guided stewardship, and pathogen- and patient-specific scenarios to provide a practical framework for intensivists: treat until infection is controlled and the patient is improving, usually about 1 week, and extend therapy only with clear justification.