Comparative Antibiotic Therapy for Subjects With Pulmonary Infiltrates in the ICU

This study will enroll 460 subjects who have new pulmonary infiltrates during their ICU stay and who are at low risk of having pneumonia, as determined using the Clinical Pulmonary Infection Score (CPIS). The study is designed to determine whether 3 days of antibiotic treatment with meropenem (with or without coverage for MRSA) for ICU subjects diagnosed with new pulmonary infiltrates can reduce the emergence of anti-microbial-resistant organisms and the isolation of a potential pathogen compared to a standard course of antibiotic therapy (minimum of 8 days of therapy with antibiotics of the primary care team's choosing). Subjects will be randomly placed in either the meropenem group or standard antibiotic therapy group. The study will also examine whether short-course therapy reduces hospital length of stay and hospital cost, without having a negative effect on subject morbidity and mortality.