Tracheostomy and Ventilator-Associated Pneumonia in Mechanically Ventilated ICU Patients: A Retrospective Matched Cohort Study

Background/Objectives: Ventilator-associated pneumonia (VAP) remains a major complication in patients requiring prolonged mechanical ventilation. The effect of tracheostomy on VAP risk remains controversial, particularly when differences in duration of mechanical ventilation are considered. This study evaluated the association between tracheostomy, VAP occurrence, and clinical outcomes in mechanically ventilated ICU patients. Methods: We conducted a retrospective matched exposed–unexposed cohort study in a tertiary-care ICU in Mexico City. Patients undergoing tracheostomy were compared with an age- and sex-matched subcohort of intubated patients receiving invasive mechanical ventilation for ≥48 h. VAP incidence was assessed using cumulative incidence, incidence density, and multivariable generalized linear models. Results: A total of 218 patients were included (55 tracheostomized and 163 intubated). VAP incidence density was similar between groups (31.5 vs. 30.3 per 1000 ventilator-days; RR 1.04, 95% CI 0.7–1.7), whereas cumulative incidence was higher among tracheostomized patients (61.8% vs. 22.7%; RR 2.7, 95% CI 1.9–3.9). Broad-spectrum antibiotics, mechanical ventilation ≥ 5 days, chronic pulmonary disease, and ICU stay remained associated with VAP occurrence in an exploratory multivariable model. Gram-negative microorganisms predominated, and antimicrobial resistance was more frequent among tracheostomized patients. Conclusions: Tracheostomy was associated with higher cumulative incidence of VAP, but a similar incidence density compared with endotracheal intubation. The crude association between tracheostomy and VAP disappeared after adjustment for confounding factors, suggesting that prolonged mechanical ventilation and ICU exposure are more important determinants of VAP risk than tracheostomy itself.