ICU-acquired pneumonia in immunosuppressed patients with acute hypoxemic respiratory failure: A post-hoc analysis of a prospective international cohort study

Objective: Intensive Care Units (ICU) acquired Pneumonia (ICU-AP) is one of the most frequent nosocomial infections in critically ill patients. Our aim was to determine the effects of having an ICU-AP in immunosuppressed patients with acute hypoxemic respiratory failure. Design: Post-hoc analysis of a multinational, prospective cohort study in 16 countries. Settings: ICU. Patients: Immunosuppressed patients with acute hypoxemic respiratory failure. Intervention: None. Measurements and main results: The original cohort had 1611 and in this post-hoc analysis a total of 1512 patients with available data on hospital mortality and occurrence of ICU-AP were included. ICU-AP occurred in 158 patients (10.4%). Hospital mortality was higher in patients with ICU-AP (14.8% vs. 7.1% p < 0.001). After adjustment for confounders and centre effect, use of vasopressors (Odds Ratio (OR) 2.22; 95%CI 1.46-3.39) and invasive mechanical ventilation at day 1 (OR 2.12 vs. high flow oxygen; 95%CI 1.07-4.20) were associated with increased risk of ICU-AP while female gender (OR 0.63; 95%CI 0.43-94) and chronic kidney disease (OR 0.43; 95%CI 0.22-0.88) were associated with decreased risk of ICU-AP. After adjustment for confounders and centre effect, ICU-AP was independently associated with mortality (Hazard Ratio 1.48; 95%CI 14.-1.91; P = 0.003). Conclusions: The attributable mortality of ICU-AP has been repetitively questioned in immunosuppressed patients with acute respiratory failure. This manuscript found that ICU-AP represents an independent risk factor for hospital mortality.