The mechanical power of prone ventilation

Prone ventilation has been shown to reduce mortality in moderate to severe acute respiratory distress syndrome (ARDS) by enhancing oxygenation, improving lung mechanics, and reducing ventilator-induced lung injury. While the arterial oxygen partial pressure (PaO2 mmHg) to fraction of inspired oxygen (FiO2) ratio (P:F) has traditionally been utilized to grade ARDS severity, multiple supplementary markers of oxygenation and ventilation, such as the oxygenation index (OI) and ventilatory ratio (VR), offer additional insight on pulmonary function in addition to prognostic information for outcomes in ARDS. Mechanical power (MP), a comprehensive marker used to quantify the total energy transferred from the ventilator to the lungs by combining tidal volume, distending pressure, flow and respiratory rate, has recently gained attention as a potential future target of lung protective ventilation. Here we present an illustrative case of how prone positioning may lead to improved objective and physiologic markers of lung mechanics related to these variables and review the available literature. Keywords: Mechanical power, Prone ventilation, ARDS