Rationale and Study Design of Provent-An International Multicenter Observational Study on Practice of Ventilation in Critically Ill Patients without ARDS

Background: Use of lower tidal volumes during mechanical ventilation is associated with reduced morbidity and mortality of Intensive Care Unit (ICU) patients with the Acute Respiratory Distress Syndrome (ARDS). Use of lower tidal volumes could also protect ICU patients without ARDS. While use of higher tidal volumes is strongly discouraged in ARDS patients, guidelines do not yet recommend on tidal volume size in patients not suffering from this complication, resulting in unwanted variable mechanical ventilation settings amongst ICU patients. Purpose: The present study aims to determine ventilation characteristics, including tidal volume size in intubated and mechanically ventilated patients in ICUs in Europe, Australia and the Americas. Ventilation characteristics and outcomes are compared among patients without ARDS, patients at risk for ARDS and patients with mild, moderate or severe ARDS. Methods: The ‘PRatice of VENTilation in critically ill patients without ARDS’ study (PRoVENT) is an international multicenter observational study in critically ill intubated and ventilated ICU patients by the PROVENet (PROtective VENtilation Network) investigators (http://www.provenet.eu/). At least 1,000 patients under invasive mechanical ventilation are included in a time window of 7 days, and followed up to the end of stay in ICU. The primary endpoint is the variability of tidal volume size in ventilated patients in ICUs in Europe, Australia and the Americas. Conclusion: PRoVENT is designed to investigate and compare tidal volume settings in patients without ARDS, patients at risk for ARDS, and patients with mild, moderate or severe ARDS, and to determine the impact of tidal volume size on important clinical endpoints, in particular patients without ARDS. PRoVENT shall provide information on ventilator settings that could be used in future trials of ventilation, especially in ICU patients without or at risk for ARDS