Impact of a multifaceted prevention program on ventilator-associated pneumonia including selective oropharyngeal decontamination

Abstract

Purpose: We describe the impact of a multifaceted program for decreasing ventilator-associated pneumonia (VAP) after implementing nine preventive measures, including selective oropharyngeal decontamination (SOD).

Methods: We compared VAP rates during an 8-month pre-intervention period, a 12-month intervention period, and an 11-month post-intervention period in a cohort of patients who received mechanical ventilation (MV) for > 48 h. The primary objective was to assess the effect on first VAP occurrence, using a Cox cause-specific proportional hazards model. Secondary objectives included the impact on emergence of antimicrobial resistance, antibiotic consumption, duration of MV, and ICU mortality.

Results: Pre-intervention, intervention and post-intervention VAP rates were 24.0, 11.0 and 3.9 VAP episodes per 1000 ventilation-days, respectively. VAP rates decreased by 56% [hazard ratio (HR) 0.44, 95% CI 0.29-0.65; P < 0.001] in the intervention and by 85% (HR 0.15, 95% CI 0.08-0.27; P < 0.001) in the post-intervention periods. During the intervention period, VAP rates decreased by 42% (HR 0.58, 95% CI 0.38-0.87; P < 0.001) after implementation of eight preventive measures without SOD, and by 70% after adding SOD (HR 0.30, 95% CI 0.13-0.72; P < 0.001) compared to the pre-intervention period. The incidence density of intrinsically resistant bacteria (to colistin or tobramycin) did not increase. We documented a significant reduction of days of therapy per 1000 patient-days of broad-spectrum antibiotic used to treat lower respiratory tract infection (P < 0.028), median duration of MV (from 7.1 to 6.4 days; P < 0.003) and ICU mortality (from 16.2 to 13.5%; P < 0.049) for patients ventilated > 48 h between the pre- and post-intervention periods.

Conclusions: Our preventive program produced a sustained decrease in VAP incidence. SOD provides an additive value.

Keywords: Intensive care unit; Multimodal strategy; Selective oropharyngeal decontamination; Ventilator-associated pneumonia.

Fig. 1

Compliance over the three periods for the nine ventilator-associated pneumonia (VAP) preventive measures, and for global compliance. Compliance was defined for each assessable preventive measures (represented as a percentage) and global compliance is expressed as median (IQRs) for all ventilator-days assessable; SOD selective oropharyngeal decontamination. a Significant P value between the pre-intervention and intervention periods, b significant P value between the intervention and post-intervention periods, c significant P value between the pre-intervention and post-intervention periods, d significant P value between the three periods

Fig. 2

Segmented Poisson regression analysis, comparing incidence rates of ventilator-associated pneumonia (VAP) in the pre-intervention, the intervention period without SOD, implementation of SOD and post-intervention period according to months. SOD Selective oropharyngeal decontamination. Circles indicate first VAP incidence rates per 1000 ventilation-days according to months, horizontal lines estimated first VAP incidence rates per 1000 ventilation-days by period, blue line pre-intervention period, red line intervention period without SOD, gray line implementation of SOD period, and green line post-intervention period, vertical orange lines delimitations of time periods, bars VAP number according to months

Fig. 3

Cumulative cause-specific hazard (a) and daily hazard rates (b) of ventilator-associated pneumonia in the pre-intervention period, the intervention period without SOD, implementation of SOD and the post-intervention period using Cox proportional cause-specific hazard regression. a, b Blue lines represent the pre-intervention period, red lines the intervention period without SOD, gray lines the period after implementation of SOD, green lines the post-intervention period. b Dashed lines empirical daily hazard of VAP, solid lines smoothed hazard function