During assisted ventilation in patients with hypoxemic respiratory failure and acute respiratory distress syndrome (ARDS), achieving a balance between ventilator support and patient effort is essential. Contemporary approaches favor light sedation and limited use of neuromuscular blocking agents: most recent evidence would suggest that spontaneous breathing should be encouraged for as long as possible, provided that excessive inspiratory effort does not injure the lungs or the diaphragm. While spontaneous breathing is beneficial in case of mild-moderate hypoxemia, it may become injurious in moderate-to-severe patients (PaO2/FiO2 2O), and the inspiratory effort from the maximum negative deflection (ΔPocc ‒ optimal range: 5-14 cmH2O). Plateau pressure can be measured to estimate total lung stress and calculate respiratory system compliance and driving pressure: driving pressure values above 12 cmH2O are associated to increased mortality. These measurements can be performed bedside without additional equipment, and should be integrated for comprehensive understanding of patient's individual respiratory mechanics and workload. In this narrative review, we provide a practical overview of these monitoring techniques and their physiological rationale, aiming to guide safe and effective maintenance of spontaneous breathing during invasive ventilation in hypoxemic patients.
Mastropietro et al. (Mon,) studied this question.