| Preintervention period | Postintervention period | Difference (95% CI) | p Value | ||
| Entire population admitted to ICU | |||||
| Total number of patients | 1059 | 1075 | |||
| % male | 58% | 59% | −1% (−5% to 3%) | 0.43* | |
| Mean age (years) | 55.9 | 54.4 | 1.5 (0 to 3) | 0.06† | |
| Median (IQR) APACHE II score | 17 (12–23) | 17 (11–23) | 0 | 0.91‡ | |
| Median (IQR) length of stay (days) | 1.9 (0.9–4.9) | 2.1 (0.9–4.85 | 0.2 | 0.78‡ | |
| ICU mortality | 19% | 20% | −0.7% (−4% to 2.6%) | 0.6* | |
| Patients “at risk” (ie, length of stay ⩾48 h) | 643 | 667 | |||
| Number of at-risk “ventilator days” | 3771 | 3777 | |||
| Population with clinically suspected VAP | |||||
| Number with clinically suspected VAP | 110 (17%) | 94 (14%) | −3% (−6% to 1%) | 0.16* | |
| Incidence of suspected VAP (per 1000 ventilator days) | 29.1 | 24.9 | |||
| Median (IQR) APACHE II score | 23 (18–26.5) | 20 (16–24) | 3 | 0.02‡ | |
| Number of suspected VAPs undergoing bronchoscopic diagnosis | 41 (37%) | 53(58%) | 19% (5 to 32%) | 0.004* | |
| Cases of microbiologically confirmed VAP | 68 (62%) | 36 (40%) | −22% (−36% to −10%) | 0.0012* | |
| % Gram-negative organisms | 51% | 62% | 11% (−37% to 15%) | 0.35* | |
| Incidence of confirmed VAP (per 1000 ventilator days) | 18 | 9 | |||
| Mean “antibiotic days” | 9.1 | 7.2 | −1.8 (−3.8 to 0.4) | 0.08† | |
| Mortality | 37.5% | 17% | −20.5% (−22% to −19%) | 0.003* | |
| 1Median (IQR) duration of ventilation | 16 (10–30) | 19 (10–27) | 3 | 0.6 | |
*By z test for proportions.
†By t test.
‡By Mann–Whitney U test.
APACHE II, Acute Physiology and Chronic Health Evaluation II; BAL, bronchoalveolar lavage; ETA, endotracheal aspirate; ICU, Intensive Care Unit; IQR, interquartile range; VAP, ventilator-associated pneumonia.