Antibiotic class Cases (n= 38) Controls (n=38) p  value
Glicopeptydes, n (%) 11 (28,95) 4 (10,53%) 0,04
Glicopeptydes-days 13,54  ±  11,55 7,5  ± 8,27 0,76
Antifungines, n (%) 7 (18,42) 2 (5,26) 0,07
Carbapenems, n (%) 8 (21,05) 2 (5,26) 0,04
Carbapenems-days 17,37  ±  12,55 20  ± 5,66 0,69
β-lactams, n (%) 26 (68,42) 23 (60,53) 0,16
β-lattams-days 8,42  ±  10,27 8,65 ±  7,26 0,94
Fluoroquinolones, n (%) 3 (7,89) 6 (15,79) 0,17
Fluoroquinolones-days 12,83  ±  10,04 7,5  ±  7,29 0,20
Aminoglycosides, n (%) 10 (26,32) 2 (5,26) 0,02
Aminoglycosides-days 11,2  ±  10,84 13 ± 8,72 0,66
Cephalosporins, n (%) 3 (7,89) 3 (7,89) 1
Cephalosporins-days 5,67  ±  6,43 12 ±  9,16 0,08
N° of administered antibiotic classes 2,03 ± 1,88  1,18 ± 1,56 0,01
NOTE: Values express the number of patients receiving a specific antibiotic class. Cases: Patients with Pseudomonas-VAP; Controls: Patients with VAP caused by other Gram-negative.
Table 2: Use of antimicrobial agents before the diagnosis of VAP