Risk factors for Pseudomonas VAP Cases (n=38) Controls (n=38) p value
Age, years 54.03  ± 18.82 55.9  ± 17.62 0,65
Female Sex (%) 9 (23,68) 10 (26,32) 0,08
Patients baseline conditions (%)      
Alcohol 3 (7,89) 2 (5,26) 0,64
Drugs abuse 1 (2,63) 1 1
Cirrhosis 2 (5,26) 0 0,09
Diabetes 6 (15,79) 3 (7,89) 0,28
COPD 10 (26,32) 5 (13,16) 0,15
Chronic steroid therapy (%) 7 (18,42) 4 (10,53) 0,32
HIV 0 1 (2,63) 0,24
Surgery (%) 20 (52,63) 22 (57,89) 0,64
Charlson Comorbidity Index 2,10  ± 2,34 1,47  ± 2,12 0,04
Previous 6 months hospitalisation (%) 17 (44,74) 5 (13,16) 0,03
Provenance from other wards (%) 25 (65,79) 12 (31,58) <0,01
Predicted mortality by SAPS     0,54
SAPS II 46,8  ± 16,95 46,65  ± 14,09  
SAPS III 59,87  ± 24,83 66  ± 15,04  
Admission pathology (%)      
Neurologic 6 (15,79) 13 (34,21)  
 Cardiocirculatory 10 (26,32) 2 (5,26) 0.04
Respiratory 7 (18,42) 5 (13,16)  
Trauma 12 (31,58) 18 (47,37)  
Central venous catheter (%) 36 (94,74) 36 (94,74) 0,64
Number of catheter-days 10,31  ± 10,41 7 ,35   ± 7,71 0,19
Dialysis (%) 3 (7,89) 3 (7,89) 1
Length of mechanical ventilation, days 9,90  ± 10,28 7,19  ± 7,89 0,26
Tracheostomy (%) 30 (78,95) 21(55,26) 0,03
NOTE: Cases: Patients with Pseudomonas-VAP; controls: Patients with VAP caused by other Gram-negative.
Table 1: Univariate analysis of risk factors for VAP caused by Pseudomonas aeruginosa