Abstract
Ventilator-induced lung injury continues to limit outcomes in patients with acute respiratory failure despite established lung-protective strategies.Mechanical power, the rate of energy transfer from the ventilator to the respiratory system, has emerged as an integrative index of ventilator-induced stress. Experimental studies indicate that cumulative and dissipated energy, rather than isolated pressures or volumes, drive lung injury. Observational and registry data consistently link higher mechanical power with increased mortality in acute respiratory distress syndrome and mixed intensive care unit populations, with thresholds of ∼16-18 J·min(-1) associated with increased risk. Normalised indices (e.g. mechanical power per predicted body weight or per compliance) often outperform absolute mechanical power as predictors of outcome. Strategies to minimise mechanical power include individualised positive end-expiratory pressure titration, driving pressure limitation, and an optimised respiratory rate. Complementing traditional physiological analysis, this review highlights the emerging role of technological integration, specifically closed-loop ventilation and artificial intelligence-driven prediction models, as essential tools to bridge the gap between theoretical mechanical power concepts and bedside application.Mechanical power provides a unifying physiological framework that integrates volume, pressure, flow and frequency into a single descriptive measure of ventilatory load. While higher mechanical power is consistently associated with worse outcomes, current evidence does not support titrating ventilation to pre-defined numerical power thresholds, and prospective randomised trials are required to determine whether mechanical power-informed strategies improve patient-centred outcomes. Mechanical power should therefore be regarded as a contextual physiological descriptor rather than a standalone therapeutic target.