Fluid Responsiveness in Post-cardiac Surgery

Study Overview
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Brief Summary
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the study aims to examine the validity of combined end-expiratory and end-inspiratory occlusion test and tidal volume challenge test for prediction of fluid responsiveness in immediate post-cardiac surgery patients

Detailed Description
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multiple studies prove that dynamic variables based on heart-lung interactions accurately can predict fluid responsiveness in mechanically ventilated patients, including pulse pressure variation (PPV) and stroke volume (SV) variation. Furthermore, passive leg raising (PLR), end-expiratory occlusion test, and tidal volume challenge test, Mini-fluid challenge are currently available to assess fluid responsiveness.

Official Title
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The Validity of Combined End-expiratory and End-inspiratory Occlusion Test and Tidal Volume Challenge Test for Prediction of Fluid Responsiveness in Immediate Post-cardiac Surgery Patients

Conditions
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Fluid Overload, Cardiac Surgery, Postoperative Complications

Intervention / Treatment
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* Procedure: Combined end-expiratory occlusion and end-inspiratory occlusion test
* Procedure: Tidal volume challenge test


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients on mechanical ventilation Patients ≥18 years of age patients undergoing cardiac surgery (coronary artery bypass graft, valve repair/ replacement, combined cardiac surgery) patients with normal systolic function of the left and right ventricle patient is mechanically ventilated with a protective lung strategy Exclusion Criteria: Patients with Spontaneously breathing activity Patients undergoing emergent cardiac surgery. Patient with severe peripheral arterial occlusive disease Pregnant women Contraindication of passive leg raising test unstable post-operative course Post-operative complications such as uncontrolled bleeding, severe neurologic impairment, or accidental mechanical complications; presence of residual severe tricuspid or any valvular regurgitations low cardiac output, low ejection fractions (EF ≤45%) open chest,Pao2/Fio2 ≤ 200

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
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: occlusions test<br>Combined end expiratory (EEO) and inspiratory occlusion (EIO) test. A 15-s EEO separated by a time window of 1 minute to allow the hemodynamic parameters to return to baseline followed by a 15-s EIO | Procedure: Combined end-expiratory occlusion and end-inspiratory occlusion test<br>* The EEO test will be performed by interrupting the mechanical ventilation at end-expiration over 15 seconds using the end-expiratory hold button available on the ventilator. The EIO test will be performed by interrupting the mechanical ventilation at end-inspiration over 15 seconds using the end-inspiratory hold button available on the ventilator.<br>|
| Active Comparator: challenge test<br>Tidal volume (TV) challenge test (transient increase of TV from 6 to 8 mL/kg for 1 minute) | Procedure: Tidal volume challenge test<br>* elevating tidal volume from 6 ml/kg to 8 ml/kg for only 60 seconds<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The number of volume responder participants could be detected using each fluid responsiveness test | The number of volume responder participants could be detected using each fluid responsiveness test including tidal volume challenge test and combined end-expiratory occlusion and end-inspiratory occlusion test | immediate postoperative period |