Veno-venous Extracorporeal CO2 Removal in ARDS-patients to Treat Respiratory Acidosis

Study Overview
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Brief Summary
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Hypothesis: Extracorporeal removal of CO2 can treat hypercapnia and respiratory acidosis, which allows application of lung protective ventilation. This downgrading of mechanical ventilation promotes better and more quickly lung recovery. Aim: The aim of the study is to treat respiratory acidosis and to reduce plateau pressures by using an extracorporeal removal of CO2 (ECCO2-R). This prospective study will include 10 patients with an Acute Respiratory Distress Syndrome (ARDS). ARDS is an inflammatory response in the lungs, the onset is acute with pulmonary oedema and shows bilateral densities on chest radiography. The take up of oxygen and the loss of CO2 in the lungs are difficult. Moreover the patient's blood can become acidic due to too much CO2. To promote a better gas-exchange, the patient with ARDS will be mechanically ventilated. This can be aggressive and harmful for the lungs. With the use of an extra-corporeal CO2-remover, CO2 can be removed so that the mechanical ventilation setting will be less aggressive and will decrease lesions in the lung. The veno-venous extracorporeal CO2-remover pumps blood from a vein via a catheter through an oxygenator (gas exchanger that adds oxygen to the blood and extracts carbon dioxide from the blood) and back into a vein. The investigators will use a standard dialysis catheter that will be put in a large vein. To prevent clotting of the system, the patient will receive heparin. In the study the investigators will work in periods of two hours, the situation before and after carbon dioxide removal will be compared. With this study the investigators want to prove that the CO2 in the blood decreases with at least 20 % with the use of the extracorporeal CO2 remover. More over the investigators want to prove that lower mechanical ventilation settings (thanks to CO2-removal by the ECCO2-R) will produce fewer lesions to the lungs.

Official Title
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Veno-venous Extracorporeal CO2 Removal in ARDS-patients to Treat Respiratory Acidosis.

Conditions
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ACUTE RESPIRATORY DISTRESS SYNDROME

Intervention / Treatment
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* Procedure: extracorporeal removal of CO2 (ECCO2-R)
* Procedure: No extracorporeal CO2-removal


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Acute onset of ARDS criteria on chest X-ray or CT scan Moderate (PaO2/ FiO2 <200) or severe ARDS (PaO2/ FiO2 <100) (FiO2: fraction of inspired oxygen) Respiratory acidosis with pH< 7,25, With plateau pressure of 28cmH20 or higher, Exclusion criteria: <18 years of age Pregnancy Obesity with BMI> 30 Contraindication for anticlotting therapy Chest wall abnormalities No presumed consent of representatives

Ages Eligible for Study
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Minimum Age: 18 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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: extracorporeal CO2<br> | Procedure: extracorporeal removal of CO2 (ECCO2-R)<br>* To promote a better gas-exchange, the patient with ARDS will be mechanically ventilated. This can be aggressive and harmful for the lungs. With the use of an extra-corporeal CO2-remover, CO2 can be removed so that the mechanical ventilation setting will be less aggressive and will decrease lesions in the lung. The veno-venous extracorporeal CO2-remover pumps blood from a vein via a catheter through an oxygenator (gas exchanger that adds oxygen to the blood and extracts carbon dioxide from the blood) and back into a vein.<br>Procedure: No extracorporeal CO2-removal<br>* Patients are their own control group.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To obtain a reduction of 20% in arterial partial CO2 pressure (PaCO2) after the first two hours of ECCO2-R therapy. | Arterial blood gasses, ventilator settings will be measured. | After the first two hours of ECCO2-R therapy, every 2 hours for a maximum of 5 days. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Reduction in Plateau pressures to levels between 25 and 28 cm H2O. | Arterial blood gasses and ventilator settings will be measured. | Every 2 hours during procedure for a maximum of 5 days. | 
| • Reduction in tidal volumes to 6ml/kg predicted body weight (PBW) or lower, with a minimum of 3ml/kg PBW. | Arterial blood gasses and ventilator settings will be measured. | Every 2 hours during the procedure for a maximum of 5 days. | 
| Increase in pH to the normal range of 7,35 to 7,45. | Arterial blood gasses and ventilator settings will be measured. | Every 2 hours during the procedure for a maximum of 5 days. |