Changes in Cerebral Oxygenation During the Prone Position in Patients With Acute Respiratory Distress Syndrome

Hypoxemia may be refractory to protective ventilation during the acute respiratory distress syndrome (ARDS), justifying the use of other therapies that improved oxygenation and decreased mortality, including prone position (PP). During ARDS, the majority of patients are responders to PP with increased PaO2 due to homogenization of the ventilation-perfusion ratio. Despite changes in intra-thoracic and intra-abdominal pressure, hemodynamic parameters are not changed. Besides the fact that the PP improves systemic oxygenation is it the same on cerebral oxygenation? No study has investigated the cerebral oxygenation during PP in patients with ARDS. The cerebral oxygenation may be altered due to the position of the patient and high levels of positive end-expiratory pressure. This decrease oxygenation may be responsible for cognitive impairment when patients awake. NIRS (Near Infrared Spectroscopy) is a noninvasive tool, capable of delivering information on cerebral oxidative metabolism and its hemodynamic status. It can be used routinely for the management of resuscitation in Intensive Care Unit (ICU) patients. This study is to investigate cerebral oxygenation during prone position in the investigators' patients of ICU.