Venous Oxygen Saturation During ECMO Support

Study Overview
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Brief Summary
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Extracorporeal veno-arterial membrane oxygenation (ECMO-VA), are used to manage refractory cardiogenic shocks by replacing the failed heart-lung block. The Extracorporeal Life Support Organisation guidelines considers that the effectiveness of these techniques must be evaluated on the adequacy of tissue perfusion biomarker, of which is O2 saturation of venous blood found in the pulmonary artery using a Swan-Ganz catheter (SVO2) or in the superior vena cava/right atrium using a central venous catheter (ScVO2). During ECMO support, it can be also measured directly in the venous ECMO cannula (SmVO2). However, due to the difference in tips locations of the venous cannula of ECMO-VA, the central venous catheter and the Swan-Ganz catheter, and rheological issues, the SmVO2, SVO2 and ScVO2 values obtained may be different. Further we hypothesised that the level of admission flow may also affect the correlation between these different variables. The aim of this experimental study is to investigate the concordance of the saturation of venous blood collected from these 3 measurement sites. The primary objectives is to compare the concordance of ScVO2 and the SmVO2, the two more easily and systematically available variables The secondary objectives were : to evaluate the concordance of the 3 variables describing oxygen saturation to analyse the primary objectives during prespecified and calibrated flow changes analyse the association between these 3 variables with prognosis variables (Perfusion index, lactatemia, CO2 veno-arterial differences, SOFA score, SAPS II, successful weaning from the ECMO) analyse in an ancilary study the concordance between SmVO2 measured using blood sample and the value obtained using a continuous monitoring of SVO2 through the circuit.

Detailed Description
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Extracorporeal veno-arterial membrane oxygenation (ECMO-VA), are used to manage refractory cardiogenic shocks by replacing the failed heart-lung block. The Extracorporeal Life Support Organisation guidelines considers that the effectiveness of these techniques must be evaluated on the adequacy of tissue perfusion biomarker, of which is O2 saturation of venous blood found in the pulmonary artery using a Swan-Ganz catheter (SVO2) or in the superior vena cava/right atrium using a central venous catheter (ScVO2). During ECMO support, it can be also measured directly in the venous ECMO cannula (SmVO2). However, due to the difference in tips locations of the venous cannula of ECMO-VA, the central venous catheter and the Swan-Ganz catheter, and rheological issues, the SmVO2, SVO2 and ScVO2 values obtained may be different. Further we hypothesised that the level of admission flow may also affect the correlation between these different variables. The aim of this experimental study is to investigate the concordance of the saturation of venous blood collected from these 3 measurement sites. The primary objectives is to compare the concordance of ScVO2 and the SmVO2, the two more easily and systematically available variables The secondary objectives were : to evaluate the concordance of the 3 variables describing oxygen saturation to analyse the primary objectives during prespecified and calibrated flow changes analyse the association between these 3 variables with prognosis variables (Perfusion index, lactatemia, CO2 veno-arterial differences, SOFA score, SAPS II, successful weaning from the ECMO) analyse in an ancilary study the concordance between SmVO2 measured using blood sample and the value obtained using a continuous monitoring of SVO2 through the circuit.

Official Title
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Comprehensive and Comparative Analysis of Venous Oxygen Saturation During ECMO Support: a Pilot Study

Conditions
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Cardiogenic Shock

Intervention / Treatment
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* Other: ECMO flow


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Weight >50 kg Veno-arterial ECMO with impending removal (for recovery, heart transplantation or LVAD/BIVAD implantation or support futility) Venous catheter tip positioned in the superior vena cava or right heart Arterial line for blood pressure monitoring Given informed consent Exclusion Criteria: Pregnancy Absence of arterial line or central venous catheter Hemodynamic instability under ECMO support Malposition of ECMO venous canula

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: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: patients<br>patients receiving temporary veno-arterial assistance whose weaning, or transfer to a heart transplant, or to long-term assistance or discontinuation is envisaged. | Other: ECMO flow<br>* Dynamic changes in ECMO flow and SvO2 measurement at the 3 different sites.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the intraclass correlation coefficient (ICC) between SECMOO2, and ScVO2 in the initial assist condition of 2-3 L/min (after 30 minutes of stability) | the intraclass correlation coefficient (ICC) between SECMOO2, and ScVO2 in the initial assist condition of 2-3 L/min (after 30 minutes of stability). Due to the importance of patient position, measurements will be standardized in supine position or with head of bed inclination less than 30% SVO2 measured on ECMO circuit and in patient's superior vena cava. | after 30 minutes of stability in the initial assistance condition (condition 1) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ICC between SVO2 and SECMOO2 measured after 30 minutes of stability in the initial assist condition (2-3 L/min), in patients with a Swan-Ganz catheter | The intraclass correlation between SVO2 and SECMOO2 measured after 30 minutes of stability in | after 30 minutes of stability in the initial assistance condition (condition 1) | 
| ICC between ScVO2 and SVO2 measured after 30 minutes of stability | Intracclass correlation between ScVO2 and SVO2 measured respectively in superior vena cava and pulmonary artery | after 30 minutes of stability in the initial assistance condition (condition 1) | 
| Association between changes in SCVO2 and SECMOO2 measured at differents flow levels | Changes in ScVO2 and SECMOO2 are measured at 4 differents conditions from Baseline (Condition 1). Those condictions will consist in 2 successive increaments in ECMO flow of 1000 ml each (Condition 2 and condition 3), followed by a return to the baseline ECMO Flow ( Condition 4) | More than 30 minutes of stability between each condition | 
| Association between changes in SVO2 and SECMOO2 measured at differents flow levels | Changes in ScVO2 and SECMOO2 are measured at 4 differents conditions from Baseline (Condition 1). Those condictions will consist in 2 successive increaments in ECMO flow of 1000 ml each (Condition 2 and condition 3), followed by a return to the baseline ECMO Flow ( Condition 4) | More than 30 minutes of stability between each condition | 
| Association between each SVO2 derived variable with macrocirculatory, microcirculatory variables | Association between ScVO2, SVO2, SECMOO2 with VIS score , Peripheral Perfusion Index and capillary refill time and arterial lactate | More than 30 minutes of stability between each condition | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Refractory cardiogenic shock, Extracorporeal life support, venous oxygen saturation, physiology