Respiratory Variations of the Diameter of Superior Vena Cava for Predicting Fluid Responsiveness After Cardiac Surgery

Study Overview
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Brief Summary
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In a recent study (Vignon 2017), respiratory variations of the diameter of superior vena cava had a greater diagnostic accuracy than pulse pressure variations and inferior vena cava respiratory variations in 540 medical and surgical ICU patients. But this indicator has not been investigated yet in cardiac surgery. The investigator aim to study respiratory variations of superior vena cava for predicting fluid responsiveness after cardiac surgery. In post-operative cardiac surgery patients with hemodynamic failure, the investigator will measure respiratory vena caval variations with TEE (Trans oesophageal echocardiography). Then, the investigator will evaluate fluid responsiveness after a fluid challenge (Trendelenburg). A ROC curve will be constructed in order to assess the optimal sensitivity and specificity of this parameter.

Official Title
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Respiratory Variations of the Diameter of Superior Vena Cava for Predicting Fluid Responsiveness After Cardiac Surgery

Conditions
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Transesophageal Echocardiography, Vena Cava Superior

Intervention / Treatment
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* Other: Trans oesophageal echocardiography
* Other: Trendelenburg test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Hemodynamic instability with hypotension, Low cardiac output or norepinephrine requirements in the first 6 post-operative hours. Exclusion Criteria: TEE (Trans oesophageal echocardiography) contra-indication Trendelenburg contra-indication

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Hemodynamic instability with hypotension<br> | Other: Trans oesophageal echocardiography<br>* Transoesophageal echocardiography : it's a standard practice for this patient<br>Other: Trendelenburg test<br>* Trendelenburg test : it's a standard practice for this patient<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| diameter of vena cava superior | measured with trans oesophageal echocardiography | at 6 post-operative hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| % of respiratory variations of maximal Doppler velocity in left ventricular outflow tract | measured with trans oesophageal echocardiography | at 6 post-operative hours | 
| % of respiratory variations of maximal Doppler velocity in pulmonary artery | measured with trans oesophageal echocardiography | at 6 post-operative hours | 
| % of pulse pressure respiratory variations | measured with trans oesophageal echocardiography | at 6 post-operative hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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fluid responsiveness, cardiac surgery