Device no longer available in Singapore

This study evaluates the use of ultra-protective ventilation, where very low ventilation volumes are used, in patients with severe acute respiratory distress syndrome (ARDS) meeting criteria to nurse in the prone position. Half the patients will receive ultra-protective ventilation support by extracorporeal carbon dioxide removal, while the other half will receive conventional lung protective ventilation.

Current best practices for management of severe ARDS include lung protective ventilation and nursing in the prone position. However, the best lung protective strategy is not currently established and using smaller ventilation volumes than standard lung protective ventilation suggest lung recovery is improved.

Application of smaller ventilation volumes requires extracorporeal carbon dioxide removal, using a device similar to a dialysis to remove carbon dioxide directly from the blood. One such device in the Prismalung, it removes blood through a catheter, much like a dialysis catheter, pumps it through a gas exchange cartridge which removes carbon dioxide. The gas exchange cartridge functions in a similar way to a dialysis filter, except it allow gases to pass through, unlike dialysis filters which allow passage of fluid and small molecules.

Inclusion Criteria:

• Admitted to MICU with respiratory failure and intubated
• ARDS criteria per Berlin definition
• PaO2:FiO2 ratio ≤ 200 mmHg for > 6 hours with FiO2 ≥0.5
• Expected to require mechanical ventilation for >48 hours
• Reversible disease

Exclusion Criteria:

• Anticoagulation contraindicated
• Proven HIT
• Unable to obtain central venous access
• Refractory hypoxia (PaO2:FiO2 ≤80 after recruitment and proning) or other indication for ECMO
• Home oxygen use
• Severe COPD
• Interstitial lung disease
• > 7 days of mechanical ventilation
• Immunocompromised patient (bone marrow, untreated HIV, PJP)
• Advanced malignancy with life expectancy ≤ 6months

Data analysis will be blinded.