Patient Characteristics.

M = Male, F = FemaleC = Caucasian, AA = African-AmericanCOPD = Chronic obstructive pulmonary disease, MVC = motor vehicle crash (trauma), CHI = closed head injury, OD = acetaminophen overdose, AAA = abdominal aortic aneurysm, CABG = coronary artery bypass grafting, PVD = peripheral vascular disease, GSW = gun shot wound, CVA = cerebrovascular accident, CABG = coronary bypass grafting, SAH = subarachnoid hemorrhage, SDH = subdural hemorrhageculture results are from airway specimens obtained invasively (tracheal secretions or bronchoalveolar lavage)# indicates bacterium intermediate sensitivity or insensitive to initial antibiotic treatmentCPIS = clinical pulmonary infection scores (* indicates missing P/F ratios)n.a. = not applicable