Positive End-expiratory Pressure Effects to Predict Fluid Responsiveness

Study Overview
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Brief Summary
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Volume expansion is one of the main treatments for shock. A test to predict the effectiveness of volume expansion prior to administration would avoid the need for excess treatment if it proves to be unnecessary.PEEP test would be an easy alternative to the tests used in current practice.

Detailed Description
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Volume expansion is one of the main treatments for shock, with the goal of increasing cardiac preload and, consequently, cardiac output. However, this increase only occurs if there is a preload-dependence of cardiac output, which is present in 50% of cases. A test to predict the effectiveness of volume expansion prior to administration would avoid the need for excess treatment if it proves to be unnecessary. The end-expiratory pressure test (PEEP) would be to vary the PEEP in patients in shock conditions placed under mechanical ventilation. PEEP is the positive pressure maintained in the airways at the end of expiration. It opposes systemic venous return and lowers cardiac preload. It also distends the pulmonary vessels, increases their resistance and opposes the ejection of the right ventricle. The decrease in PEEP could alleviate the obstacle to venous return and thus increase cardiac preload, mimicking a volume expansion, increasing cardiac output only in the case of preload dependence. This test would be an easy alternative to the tests used in current practice. To evaluate the ability of the PEEP test to detect a preload-dependence condition, defined by a passive passive leg raising test, in patients in shock. The primary endpoint will be the area under the receiver operating characteristic (ROC) curve constructed to describe the ability of the PEEP test to detect a preload-dependency condition. We measure cardiac output by analysis of the pulse wave contour before and after the passive leg raising and PEEP test tests, then according to these tests, measurement of the cardiac output before and after volume expansion.

Official Title
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Positive End-expiratory Pressure Effects to Predict Fluid Responsiveness

Conditions
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Mechanical Ventilation

Intervention / Treatment
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* Procedure: PEEP-TEST


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years Coverage by a health insurance scheme Patient under mechanical invasive ventilation (tracheal intubation) PEEP level ≥10 cmH2O Cardiac flow monitoring device in place by the PiCCO2 system (Pulsion Medical Systems, Feldkirch, Germany). Decision by the doctors in charge of carrying out a passive leg raising test and / or a volume expansion Exclusion Criteria: Pregnancy Participation in another interventional study Patients under the protection of justice Thoracic drainage (preventing PEP changes from inducing intrathoracic and transpulmonary pressure changes from their hemodynamic effects).

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: 56 patients, one arm<br>All patients benefits of a passive leg raising test and a PEEP test to compare these two tests. | Procedure: PEEP-TEST<br>* The PEEP test will consist of lowering the PEEP level to 5 cmH2O for a maximum of 2 minutes and a minimum of 1 minute. Patients will be included if the physicians who care for them have decided to set a baseline PEEP level ≥10 cmH2O.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ability of the PEP test to detect a preload-dependency condition. | The primary endpoint will be the area under the receiver operating characteristic (ROC) curve constructed to describe the ability of the PEP test to detect a preload-dependency condition. | At the end of the hospitalization in intensive care unit (1 month maximum) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relationship between the ability of the PEEP test to detect a preload-dependancy and secondly the PEEP delta induced by the test | The secondary endpoint will be the relationship between the area under the curve constructed to describe the ability of the PEP test to detect a preload-dependency state and the PEP delta induced by the test (PEP starting, high, PEP during the test, at 5 cmH2O). | At the end of the hospitalization in intensive care unit (1 month maximum) | 
| Ability of the PEP test to detect a response to volume expansion. | The secondary endpoint will be the area under the curve constructed to describe the ability of the PEP test to detect a response to volume expansion. | At the end of the hospitalization in intensive care unit (1 month maximum) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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PEEP test preload dependancy fluid responsiveness