Figure 2. Comparison of the lowest PaO₂/FiO₂ ratios during the first 2 weeks post injury (PaO₂/FiO₂) among patients with no bacterial pathogens isolated from respiratory secretions during the first 2 weeks (NEG), patients with bacterial pathogens of any type (POS), and patients with gram negative bacteria (GN POS).

Patients in whom no bacterial cultures were collected are not included in this analysis. * = P<.05 vs. NEG.