Ultra-protective Pulmonary Ventilation Supported by Low Flow ECCO2R for Severe ARDS

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

Official Title
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Ultra-protective Pulmonary Ventilation Supported by Low Flow Extracorporeal Carbon Dioxide Removal (ECCO2R) and Prone Positioning for ARDS; a Pilot Study.

Conditions
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Respiratory Distress Syndrome, Adult

Intervention / Treatment
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* Device: Prismalung
* Other: Ultra-protective ventilation
* Other: Conventional Lung Protective Ventilation


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Conventional lung protective ventilation<br>Lung protective ventilation (6ml/kg predicted body weight). All other interventions per intensive care unit standardised ARDS management protocol | Other: Conventional Lung Protective Ventilation<br>* Ventilation with 6ml/kg predicted body weight<br>|
| Experimental: Ultra-protective ventilation<br>Ultra-protective ventilation (</= 3ml/kg predicted body weight) targeting plateau pressure of </= 25 cmH2O, supported by Prismalung. All other intervention per intensive care unit standardised ARDS management protocol | Device: Prismalung<br>* Prism lung (Baxter Healthcare/Gambro Lund, Sweden) is an extracorporeal carbon dioxide removal device. It removes blood through a double lumen catheter and pumps it through a hollow fiber gas exchange cartridge which is impervious to fluid. Carbon dioxide diffuses out, down a concentration gradient which is maintained by sweep gas flowing through the centre of the hollow fibres. The decarboxylated blood is returned to the patient through the double lumen catheter.<br>* Other names: Respiratory Dialysis;Other: Ultra-protective ventilation<br>* Ventilation with </= 3ml/kg predicted body weight<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Plateau Pressure | Ability to achieve a plateau pressure of </=25 cmH20 in the intervention arm | Duration of ventilation for severe ARDS, expected average time 10 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of stay in ICU stay |  | Duration of patient stay in ICU, expected average stay 2 weeks | 
| Length of hospital stay |  | Duration of patient stay in hospital | 
| Mortality | ICU mortality, hospital mortality, 30 day, 60 day and 90 day mortality | Monitored for 3 months | 
| Cardiac Imaging | Echocardiogram data will be collected before prone position, after prone positioning and following initiation of ultra-protective ventilation | One data set per patient during first 72 hours | 
| Extracorporeal carbon dioxide removal related complications | Complications or adverse events related to ECCO2R and associated anticoagulation | Duration of severe ARDS, expected average time frame 10 days | 
| Ventilator free days |  | 28 days | 
| All severe adverse events |  | Duration of ICU stay (anticipate average stay 1-2 weeks) | 
| Number of patient meeting proning criteria in each group |  | Duration of ICU stay | 
| Ability to successfully prone |  | Duration of ICU stay | 
| Incidence of dialysis in ICU, and ability to successfully initiate |  | Duration of ICU stay | 
| Incidence of referrals for ECMO |  | Duration of ICU stay | 
| Rate and reasons for declining consent to study participation |  | First 48 hours | 
| Enrolment rates |  | First 48 hours | 
| Lung recruitability |  | Duration of ICU stay | 
| Ventilation parameters | Data download from mechanical ventilation | Duration of mechanical ventilation | 
| Ventilator associated pneumonia rates |  | Duration of ICU stay | 
| Barotrauma complications |  | Duration of ICU stay | 
| Biomarkers of Pulmonary Inflammation | Serum will be drawn and stored for pulmonary biomarkers analysis at the above time points | Day 0, 4 and 7 |