Importance of appropriate initial antibiotic therapy and de-escalation in the treatment of nosocomial pneumonia

Inappropriate initial antibiotic therapy in nosocomial pneumonia is associated with higher mortality, longer hospital stays and increased healthcare costs. The key pathogens associated with these adverse outcomes include Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and Acinetobacter baumannii. Due to the increasing rates of resistance, a new paradigm is needed for treating nosocomial infections in the intensive care unit (ICU). Optimal initial therapy consists of a broad-spectrum antibiotic started in a timely manner and administered at the correct dose and via the correct route. Because pathogen aetiology and resistance patterns vary from one ICU to another, recommendations for initial therapy should be tailored to each institution. Selection of the broad-spectrum antibiotic should be based on the patient's risk factors (including comorbidities, duration of ventilation and recent antibiotic exposure), suspected pathogen and up-to-date local resistance patterns. After 48-72 h, the patient should be reassessed and antibiotic therapy de-escalated based on the microbiological results and the clinical response.