Airway Pressure Release Ventilation (APRV) vs conventional ventilation for patients with moderate to severe acute hypoxemic respiratory failure (RELEASE).

Approximately 130,000 adults are admitted to critical care units (CCUs) in the UK each year, 40-45% of whom require invasive mechanical ventilation (IMV). Acute hypoxaemic respiratory failure (AHRF) is the most common reason for IMV and is associated with serious morbidity and a mortality which remains high at ~40%. Although lifesaving, IMV can cause additional lung injury (termed ventilator induced lung injury - VILI).

Airway Pressure Release Ventilation (APRV) is a method of IMV which uses longer inspiration times followed by a brief expiration. The longer inspiration time enables alveolar recruitment and oxygenation while the short expiration time maintains lung volume. This reduces shear-stress damage to the alveoli, whilst maintaining adequate ventilation.

RELEASE aims to investigate, using a multi-centre, parallel group, pragmatic, randomised controlled trial design, the clinical and cost effectiveness of early APRV compared to conventional lung protective invasive mechanical ventilation(IMV) in patients with moderate-severe acute hypoxic respiratory failure (AHRF).

We aim to recruit 710 participants.

The total planned project duration is 52 months. Recruitment is anticipated to commence August 2024 for 32 months.