Mechanical ventilation remains a cornerstone of acute respiratory failure management, but ventilator-induced lung injury persists despite lung-protective strategies focused on limiting tidal volume (V T ), plateau pressure, and driving pressure. Mechanical power has emerged as a comprehensive metric that quantifies the total energy delivered to the lungs per unit time by integrating V T , airway pressures, breathing frequency, flow, and PEEP into a single physiologic measure. Observational studies through 2025 show that elevated mechanical power is associated with worse outcomes, including increased mortality, fewer ventilator-free days, and longer ICU stays, with breathing frequency identified as a major contributor even when other settings remain within protective ranges. Although no universal injurious threshold exists because of patient variability, normalization strategies such as indexing mechanical power to predicted body weight or respiratory system compliance have shown promise in improving prognostic value, although consensus on the optimal method is lacking. Currently, mechanical power should be considered a complementary bedside tool that integrates multiple ventilator variables, helps identify key contributors to lung stress and strain, and may support individualized ventilator adjustments to reduce cumulative injury risk as further evidence and technology evolve.
LeTourneau et al. (Mon,) studied this question.