A prospective observational study to find the optimal proning duration in patients with moderate to severe acute respiratory distress syndrome

Acute Respiratory Distress Syndrome (ARDS) is a critical condition marked by acute onset of respiratory failure and widespread inflammation in the lungs.Despite extensive research and recent advances, ARDS is still associated with high morbidity and mortality rates (30-50%).

Prone positioning has emerged as a promising intervention, shown to improve oxygenation and reduce mortality in severe ARDS when applied early and continuously.Prone positioning facilitates better alveolar ventilation and reduces the risk of ventilator-induced lung injury by promoting more uniform stress distribution across the lung tissues.  The gravitational gradient in pleural pressure is more evenly distributed in the prone position compared to supine, enhancing ventilation distribution in the lung’s dorsal areas, which are often severely affected in ARDS. Duration of prone positioning is an important determinant of its effectiveness, as may the interval between the onset of ARDS and its application. Recent literature suggests that early and prolonged prone positioning can potentially decrease mortality in severe ARDS by reducing ventilator-induced lung injury and multisystem organ failure. However, inconsistencies in existing studies, due to variations in patient populations, proning duration and sessions, necessitate further investigation.  Moreover, continuation of proning may cause improvement in lung oxygenation only upto a particular duration, following which the further sessions of proning may not provide any additional benefit. Also, there has not been much research done to assess the optimal duration of proning that would provide the maximum benefit in lung mechanics. Hence, an appropriately powered study is needed to re-evaluate the duration and sessions of prone ventilation that is required to provide maximum improvement in oxygenation and reduce mortality in patients with ARDS.

Research question**:**Does the benefits of prone ventilation on lung mechanics in patients with moderate to severe Acute Respiratory Distress Syndrome plateaus after 4 sessions of proning of 16h per day.