Goligher 2018.

Study name	Assessing lung inhomogeneity during ventilation for acute hypoxemic respiratory failure
Methods	Randomised controlled trial
Participants	Included: participants with ARDS (PaO₂/FIO₂ ≤ 200) Excluded: contraindication to electrical‐impedance‐tomography electrode placement (e.g. burns, chest‐wall bandaging limiting of electrode placement), contraindication to oesophageal‐catheter placement (e.g. recent upper‐GI surgery, actively bleeding oesophageal varices), respiratory failure predominantly resulting from cardiogenic cause or fluid overload, ongoing haemodynamic instability (requiring 2 vasopressor agents by continuous infusion and rising vasopressor‐infusion‐rate requirements during previous 8 hours), ongoing ventilatory instability (PaO₂/FIO₂ < 70 mmHg, pH < 7.2; ventilator‐driving pressures, PEEP, or FIO₂ increasing by more than 25% in previous 30 minutes), intracranial hypertension (suspected or diagnosed by medical team), known or suspected pneumothorax recognised within previous 72 hours, bronchopleural fistula, bridge‐to‐lung transplant, recent lung transplantation (within previous 6 weeks), attending physician deeming transient application of high airway pressures (> 40 cmH₂O) to be unsafe
Interventions	Control: PEEP level to achieve plateau pressures of 28 cmH₂O Intervention: PEEP level according to electrical‐impedance‐tomography algorithm, which selects a PEEP at which both collapse and hyperdistension of the lung are minimized. In both groups, the heterogeneity of ventilation will be assessed through electrical impedance tomography
Outcomes	Primary: intratidal‐ventilation heterogeneity Secondary: difference in optimal PEEP levels identified by several different PEEP‐titration strategies, measurement of changes in oxygenation by the PaO₂/FIO₂ ratio resulting from PEEP, transpulmonary driving pressure
Starting date	18 July 2018
Contact information	Jenna Wong, University Health Network, Toronto, Ontario, Canada
Notes

ARDS: acute respiratory distress syndrome.

BMI: body mass index.

CO₂: carbon dioxide.

ECMO: extracorporeal membrane oxygenation.

FIO₂: fraction of inspired oxygen.

ICU: intensive care unit.

MV: mechanical ventilation.

PaCO₂: partial pressure of carbon dioxide.

PaO₂: partial pressure of oxygen.

PBW: predicted body weight.

PEEP: positive end‐expiratory pressure.

SpO₂: oxygen saturation.

TV: Tidal Volume.

VFDs: ventilator‐free days.