) rectally or via pulmonary artery (PA) catheter; and/or 2) elevated total white blood count (WBC) > 10,000/ mm 3 , or > 15% immature neutrophils (bands), regardless of total WBC, or leukopenia with total WBC < 4,500/ mm 3 . Microscopic examination of the Gram stained respiratory secretions had to show the presence of microorganisms, with ≥25 polymorphonuclear cells and ≤10 squamous epithelial cells per field at 100× magnification (low-power, 10× objective).