Associação entre pressão de distensão e mortalidade em pacientes sob risco para Síndrome do Desconforto Respiratório Agudo: estudo de coorte

Abstract

Background: Although it is well known that a driving pressure (DP) higher than 15 cmH2O is associated with higher mortality in patients with ARDS, it is not established its clinical impact in patients without ARDS. Therefore, this study aimed to evaluate the association between DP and mortality in patients at risk for ARDS. Methods: A prospective cohort was carried out in the ICU of the University Hospital (Universidade Federal de Juiz de Fora, Brazil). All patients aged 18 years or older, receiving MV and with at least one risk factor for developing ARDS were included. Ventilatory parameters were collected twice daily for seven days, and patients were separated into two groups according to the DV: protective-MV (>80% of the measures of DP <15 cmH2O), and non-protective-MV (<80% of the measures of driving pressure < 15 cmH2O). The primary outcome was hospital mortality. Secondary outcomes included ICU mortality, 28-day mortality, PaO2/FIO2 at day 7. Results: We included 116 patients, 78 in the protective-MV group. The cox proportional regression, adjusted for age, SAPS-3, the use of vasopressor, and baseline values of PaO2/FIO2, PEEP, respiratory system compliance, pH and PaCO2, showed that a protective MV was associated to lower mortality at hospital (HR, 0.37; 95% CI, 0.19-0.73), lower ICU-mortality (HR, 0.40; 95% CI, 0.19-0.85), and lower 28-day mortality (HR, 0.41, 95% CI, 0.18-0.94), but not with lower levels of PaO2/FIO2 at day 7. Conclusions: The driving pressure seems to be a useful tool to set the MV in patients at risk for ARDS.