Prone Ventilation Guidelines for ARDS Patients

Introduction to Prone Ventilation

The American Thoracic Society suggests VV-ECMO in selected patients with severe ARDS (conditional recommendation, low certainty of evidence) 1
For patients with moderate to severe ARDS, prone ventilation should be implemented for 12-16 hours daily, and can be safely combined with ECMO therapy in selected cases of refractory hypoxemia 1, 2, 3

Prone positioning is strongly recommended for invasively ventilated patients with ARDS and impaired arterial oxygenation (PaO₂/FiO₂ < 150 mmHg) 4
Implementation should occur at an early stage once indicated, as early intervention is associated with better outcomes 4
Duration should be at least 12 hours, preferably 16 hours per session 2, 4
Complete (180°) prone positioning is recommended over incomplete positioning as it has a stronger effect on oxygenation and better clinical outcomes 4
Maintain lung-protective ventilation strategies during prone positioning, including low tidal volume ventilation (4-8 mL/kg predicted body weight) 5
Plateau pressures should be less than 30 cm H₂O 5
Prevention of derecruitment is crucial 2
Integration of spontaneous breathing components when appropriate 4

Relative contraindications where prone positioning should be considered only after interdisciplinary risk-benefit assessment include open abdomen 3, spinal instability 3, increased intracranial pressure (ICP) 3, cardiac arrhythmias with hemodynamic consequences 3, and shock 4
For patients with increased ICP risk, continuous monitoring is required with the head positioned in a centered position and lateral rotation avoided 4

Consider terminating prone positioning if improvement in supine oxygenation persists (4 hours after repositioning: PaO₂/FiO₂ ≥ 150 with PEEP ≤ 10 cm H₂O and FiO₂ ≤ 0.6) 4
Discontinue prone therapy if at least two positioning attempts have been unsuccessful in improving oxygenation 4

Prone positioning is suggested for ARDS patients receiving veno-venous ECMO therapy 2, 3
Consider ECMO if hypoxemia persists (PaO₂ < 55 mmHg) despite optimal mechanical ventilation and other rescue therapies including prone positioning 6
Optimization of conventional treatments (lung-protective ventilation, prone positioning) should always be undertaken before considering ECMO 7

ECMO should only be considered in carefully selected patients with severe ARDS due to its resource-intensive nature 5
ECMO programs require highly experienced staff and minimum case volumes per year 7
Organized regional or national networks with mobile ECMO teams are necessary 8
Regular staff training and continuing education are crucial 7
Quality assurance through regular audits is essential 7, 8
For hospitals without ECMO capabilities, establishing relationships with ECMO-capable institutions is advisable to facilitate timely transfer of eligible patients 6

Failure to implement prone positioning early enough in the course of ARDS 4
Inadequate duration of prone sessions (should be at least 12 hours) 2, 4
Delaying ECMO consideration in appropriate candidates with refractory hypoxemia despite optimal conventional management 6
Lack of established protocols for combined prone positioning and ECMO therapy 7