Table 5.
Risk factors for ventilator-associated pneumonia by Cox proportional hazards model
| Variable | Univariate analysis | Multivariate analysis (model 1) | Multivariate analysis (model 2) | |||
|---|---|---|---|---|---|---|
| HR (95 % CI) | P | HR (95 % CI) | P | HR (95 % CI) | P | |
| At ICU admission | ||||||
| LOD score | 1.04 (1.01, 1.09) | 0.044 | - | 0.922 | - | 0.138 |
| Transfer from other wards | 0.65 (0.45, 0.93) | 0.018 | - | 0.356 | - | 0.952 |
| Prior antibiotic treatment | 0.67 (0.48, 0.94) | 0.021 | - | 0.483 | - | 0.184 |
| Neurologic failure | 1.82 (1.07, 3.09) | 0.027 | - | 0.111 | - | 0.197 |
| Poisoning | 3.24 (1.9, 5.51) | <0.001 | 2.49 (1.31, 4.72) | 0.005 | 2.16 (1.14, 4.09) | 0.018 |
| COPD | 0.55 (0.37, 0.89) | 0.003 | - | 0.063 | - | 0.065 |
| McCabe score >2 | 0.76 (0.59, 0.99) | 0.042 | - | 0.169 | 0.726 | |
| PaO2 > 120 mmHg | 1.58 (1.11, 2.25) | 0.011 | NA | NA | 1.68 (1.16, 2.42) | 0.006 |
| During ICU stay | ||||||
| Percentage of days with PaO2 > 120 mmHg | 5.67 (3.15, 10.20) | <0.001 | 6.23 (3.26, 11.9) | <0.001 | NA | NA |
HR hazard ratio, LOD logistic organ dysfunction, COPD chronic obstructive pulmonary disease, NA not applicable. P > 0.1 by univariate analysis for: age, male gender, simplified acute physiology score II, diabetes, cardiac failure, cirrhosis, chronic dialysis, immunosuppression, all causes of ICU admission except neurologic failure, stress ulcer prophylaxis, tracheostomy, red blood cell transfusion, sedation, and neuromuscular-blocking agent use