PROJECT SUMMARY / ABSTRACT
Acute respiratory distress syndrome (ARDS) is a severe form of lung injury requiring hospitalization in intensive
care and often invasive mechanical ventilation in effort to sustain life. ARDS can result from a variety of insults
(e.g. pneumonia, sepsis, trauma, and pancreatitis), posing broad risk to the public health. With the COVID-19
pandemic, ARDS has become a leading cause of death in the US and globally. Yet, even pre-pandemic, ARDS
occurred in 10% of US ICU admissions and had an associated mortality of 30-45%. Regardless of ARDS
etiology, many survivors experience cognitive, psychological, and physical impairments persisting years after
the acute illness resolves. Thus, there remains an urgent need to identify effective ARDS therapies. Invasive
mechanical ventilation is potentially life-saving, but can worsen lung injury and patient outcomes if not precisely
titrated to attenuate lung stress, which varies by patient with overdistension and atelectrauma (repetitive
opening/closure of potentially recruitable lung). Alveolar edema and atelectasis reduce the functional aerated
lung volume, such that tidal volume scaled to estimated healthy lung size (i.e. 6 mL/kg predicted body weight)
may not always prevent overdistension. Similarly, positive end-expiratory pressure (PEEP) is routinely increased
to recruit lung in patients with more severe hypoxemia, an approach that may exacerbate overdistension injury
in patients most susceptible. An integrated strategy that mitigates the competing risks of atelectrauma and
overdistension is needed. The range of lung stress observed in patients with ARDS receiving standard-of-care
ventilation is often larger than that observed in healthy adults due to perturbed lung and chest wall mechanics,
increasing risk of both atelectrauma and overdistension. In preclinical models and human cohort studies, lung
injury and mortality are less when the ventilator is set to maintain lung stress in the healthy normal range.
PREcision VENTilation to attenuate Ventilation-Induced Lung Injury (PREVENT VILI) is a phase III multicenter
randomized trial for adults with moderate-severe ARDS that tests whether precise ventilator titration to maintain
lung stress within 0-12 cm H2O, the healthy normal range during relaxed breathing, will improve patient outcomes
compared to guided usual care. In the precision ventilation arm, PEEP will be individualized to achieve lung
stress of 0 cm H2O at end-expiration, and tidal volume individualized to achieve driving pressure of 12 cm H2O
or the lowest possible. In the guided usual care arm, PEEP will be adjusted per usual care within limits set to
avoid practice extremes; tidal volume of 6-8 mL/kg predicted body weight will be targeted unless plateau pressure
exceeds 30 cm H2O, in which case tidal volume will be lowered. We will evaluate the effect of ventilator strategy
on 60-day mortality (Aim 1), lung injury (Aim 2), and hemodynamic instability (Aim 3). Findings will help determine
the role for individualizing ventilator support to reduce lung stress in ARDS and have potential to improve survival
from this leading cause of death worldwide.