A case-control study on the clinical impact of ventilator associated tracheobronchitis in adult patients who did not develop ventilator associated pneumonia

Abstract

Objectives: The main objective was to determine whether ventilator-associated tracheobronchitis (VAT) is related to increased length of ICU stay. Secondary endpoints included prolongation of hospital stay, as well as, ICU and hospital mortality.

Design: A retrospective matched case-control study. Each case was matched with a control for duration of ventilation (± 2 days until development of ventilator-associated tracheobronchitis), disease severity (Acute Physiology and Chronic Health Evaluation II) at admission ± 3, diagnostic category and age ±10 years.

Patients: Critically ill adults admitted to a polyvalent 30-beds ICU with the diagnosis of VAT in the period 2013-2016.

Main results: We identified 76 cases of VAT admitted to our ICU during the study period. No adequate controls were found for 3 patients with VAT. There were no significant differences in demographic characteristics, reasons for admission and comorbidities. Patients with VAT had a longer ICU length of stay, median 22 days (14-35), compared to controls, median 15 days (8-27), p=.02. Ventilator days were also significantly increased in VAT patients, median 18 (9-28) versus 9 days (5-16), p=.03. There was no significant difference in total hospital length of stay 40 (28-61) vs. 35days (23-54), p=.32; ICU mortality (20.5 vs. 31.5% p=.13) and hospital mortality (30.1 vs. 43.8% p=.09). We performed a subanalysis of patients with microbiologically proven VAT receiving adequate antimicrobial treatment and did not observe significant differences between cases and the corresponding controls.

Conclusions: VAT is associated with increased length of intensive care unit stay and longer duration of mechanical ventilation. This effect disappears when patients receive appropriate empirical treatment.

Keywords: Case-control study; Estancia; Estudio caso-control; Lenght of stay; Traqueobronquitis asociada a ventilación mecánica; Ventilator-associated tracheobronchitis.