Table 2.
Bivariate and multivariate analyses of risk factors for VAP (mean ± SD)
| Bivariate analysis | Multivariate analysis | |||||
| Risk factors | VAP Group | Control Group | OR (95% CI) | P-value | OR (95% CI) | P-value |
| Respiratory failure | 34 (91.9 %) | 12 (20.0 %) | 45.3 (11.8–173.0) | <0.0001 | 11.8 (2.2–62.5) | 0.004 |
| Coma (GCS < 9) | 23 (62.2 %) | 3 (5.0 %) | 31.2 (8.2–118.9) | <0.0001 | 17.2(2.7–107.7) | 0.002 |
| Depressed consciousness | 25 (67.6 %) | 12 (20.0 %) | 29.4 (10.9–58.7) | <0.0001 | 8.8 (2.9–62.5) | 0.02 |
| Enteral feeding | 30 (81.1 %) | 14 (23.3 %) | 14.1 (5.1–38.9) | <0.0001 | 5.3 (1.0–27.3) | 0.044 |
| Length of stay | 9.4 ± 7.1 | 3.5 ± 2.3 | <0.0001 | 1.3 (1.0–1.7) | 0.023 | |
| APACHE II scores | 22.9 ± 5.2 | 15.3 ± 7.0 | <0.0001 | -- | NS | |
| Nasogastric tubing | 28 (75.7 %) | 21 (35.0 %) | 5.8 (2.3–14.5) | 0.001 | -- | NS |
| CVC | 32 (86.5 %) | 41 (68.3 %) | 3.0 1.0–7.3) | 0.044 | -- | NS |
| Diabetes mellitus | 5 (13.5 %) | 2 (3.3 %) | 4.5 (0.8–24.7) | NS | ||
| Trauma | 1 (2.7 %) | 2 (3.3 %) | 0.8 (0.1–9.2) | NS | ||
| Blood transfusion | 14 (37.8 %) | 21 (35.0 %) | 1.1 (0.4–2.6) | NS | ||
| TPN | 9 (24.3 %) | 15 (25.0 %) | 1.0 (0.4–2.5) | NS | ||
| Corticosteroids | 2 (5.4 %) | 5 (8.3 %) | 0.6 (0.1–3.4) | NS | ||
| H2 receptor antagonists | 37 (100.0 %) | 58 (96.7 %) | - | NS | ||
| Urinary catheterization | 37 (100.0 %) | 57 (95.0 %) | -- | NS | ||
| PVC | 30 (81.1 %) | 45 (75.0 %) | 1.4 (0.6–3.9) | NS | ||
| Surgical drains | 8 (21.6 %) | 11 (18.3 %) | 1.2 (0.4–3.4) | NS | ||
| Tracheostomy | 2 (5.4 %) | 1 (1.7 %) | 3.3 (0.3–38.6) | NS | ||
| Arterial cannulation | 3 (8.1 %) | -- | -- | NS | ||
Values are expressed as mean ± SD and number of patients (%). Possible risk factors for VAP were assessed with bivariate analysis. All of the risk factors which were found significant with bivariate analysis were included in a model, and multiple logistic regression analysis was done. Abbreviations: OR: odds ratio, CI: confidence interval, PVC: peripheral venous catheter, CVC: central venous catheterization, TPN: total parenteral nutrition.