The Consistency of Cardiac Output Measurements by Different Methods in VA-ECMO Patients

Study Overview
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Brief Summary
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Objective： To evaluate the consistency of cardiac output measured by different hemodynamic monitoring methods in patients with VA-ECMO To evaluate whether different hemodynamic monitoring methods can accurately detect the trend of cardiac output changes

Detailed Description
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Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been used for profound cardiogenic shock to bridge to decision,ventricular assist devices,or transplant.Close monitoring of cardiac output, especially in patients before and after intervention (such as volume expansion, diuresis, vasoconstriction, vasodilation therapy), can help to adjust the treatment strategy. Hemodynamic monitoring in ECMO patients requires familiarity with the underlying pathophysiology and circulatory mechanics of extracorporeal flow.Limited to the actual clinical situation of patients, one or two hemodynamic monitoring methods may be accepted. Is there consistency between different hemodynamic monitoring results? And whether hemodynamic monitoring can accurately detect the changes of these parameters before and after intervention is an important issue in clinical practice. This study will provide important reference for VA-ECMO patients how to choose appropriate hemodynamic monitoring tools and how to interpret the results of hemodynamic monitoring.

Official Title
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The Consistency of Cardiac Output Measurements by Different Methods in VA-ECMO Patients

Conditions
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Extracorporeal Membrane Oxygenation

Intervention / Treatment
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* Diagnostic Test: Trendelenburg Maneuver
* Diagnostic Test: dobutamine stress test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: cardiac surgery treatment with VA-ECMO mechanical ventilation hemodynamic monitoring according to patient's condition (PAC, Flotrac, echocardiography) Exclusion Criteria: age < 18 cardiac arrhythmia moderate to severe aortic, mitral and tricuspid regurgitation active hemorrhage IABP spontaneous triggering of the ventilator

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Trendelenburg Maneuver<br>The Trendelenburg position is a common treatment in medicine.It is used either as a diagnostic tool to assess fluid loading response or as a therapeutic maneuver pending fluid resuscitation.With the advantage of autotransfusion readily available,the Trendelenburg position is used for expected instantaneous effect on cardiovascular performance. | Diagnostic Test: Trendelenburg Maneuver<br>* In the Trendelenburg position, the body is laid supine with the feet higher than the head by 15-30 degrees. The venous return increases in the trendelenburg position which in turn increases the stroke volume.<br>|
| Experimental: dobutamine stress test<br>Dobutamine is a selective beta 1 receptor agonist. It [<10 ug/(kg.min)] can effectively increase myocardial contractility. | Diagnostic Test: dobutamine stress test<br>* Dobutamine was infused intravenously at the initial dose of 2.5 ug/kg/min. Echocardiography was performed after 5-10 minutes of continuous infusion, and hemodynamic data were recorded.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Baseline Cardiac Output measurement | Cardiac Output measured at baseline position（ in a supine position with the head elevated to 15° for baseline measurements ） | within1 minute at baseline position | 
| Cardiac Output measurement afterTrendelenburg Maneuver | Cardiac Output measured after Trendelenburg Maneuver | 1 minute after starting Trendelenburg Maneuver | 
| Cardiac Output measurement after Dobutamine stress test | Cardiac Output measured after dobutamine stress test | 5 minutes after dobutamine stress test | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pulmonary artery catheter, echocardiography, fluid responsiveness, extracorporeal membrane oxygenation