The mortality of patients with acute respiratory distress syndrome (ARDS) remains high despite recent advances in lung-protective strategies and even after the overall improvement in intensive care (management of sepsis, hemodynamics, organ failure, and control of nosocomial infections). The use of mechanical ventilation (MV) plays a fundamental therapeutic role in this scenario. It allows for respiratory muscle rest, maintenance of oxygen transport to tissues, elimination of CO2 production, and finally, lung rest and protection in patients with excessive ventilatory demand.
On the other hand, recent studies have also shown that MV can cause iatrogenic injury and inflammation in the lung parenchyma, imposing a significant mechanical energy load and dissipation in the lung parenchyma (mechanotransduction). This effect is more pronounced in patients with low lung compliance or in those receiving inadvertently high tidal volumes, resulting in high distending pressure. Thus, despite being life-saving in the short term, MV may perpetuate or exacerbate pre-existing lung injury.
Various strategies have been proposed to aid in the ventilatory management of patients with ARDS. Among them, the use of higher PEEP values and the prone position have proven beneficial, especially when resulting in the stabilization of diseased alveoli or even promoting the recruitment of new alveolar units, associated with improved gas exchange. Both maneuvers, however, involve considerable risks: PEEP often causes impairments to venous return, and the prone position presents technical/logistical limitations for its widespread use, or even severe adverse effects during its implementation (ocular injury, accidental extubation, arrhythmias, catheter disconnection, etc.).
The hypothesis of this study is that automated lateral decubitus positioning (performed by a rotational bed with proper patient support), guided by monitoring through Electrical Impedance Tomography (EIT), could replace or minimize the need for prone positioning or the need for higher PEEPs in critical patients, resulting in effective alveolar recruitment and improvements in gas exchange, compliance, and lung aeration without affecting the hemodynamic condition.