Automated Inferior Vena Cava Collapsibility Index Fluid Responsiveness in Ventilated Patients After Cardiac Surgery.

Study Overview
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Brief Summary
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Echocardiographic measurement of inferior vena cava (IVC) collapsibility index (CI) with automated software analyses has been introduced. This study aims to assess the accuracy of IVC-CI (caval index) measurements as well as the ability to track fluid responsiveness (FRes) over time comparing the automated echocardiographic method with the pulse pressure variation (PPV) technique and the manual echocardiographic method in cardiac surgery patients.

Detailed Description
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It is expected to have insights about the concordance rate. The automated echocardiographic method of measuring CI method may or may not meet the criteria for interchangeability with the thermodilution technique or the manual echocardiographic method.

Official Title
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Automated Inferior Vena Cava Collapsibility Index for Assessing Fluid Responsiveness in Ventilated Patients After Cardiac Surgery.

Conditions
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Hemodynamic Monitoring, ICU, Cardiac Surgery

Intervention / Treatment
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* Diagnostic Test: Automated echocardiographic inferior vena cava measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. Age more than18 years old. 2. Cardiac surgical patients including (coronary artery bypass graft surgery, valvular surgeries, and aortic dissection surgeries) 3. Need for decision to administer IV fluids (hypotension that require assessment and possible fluid boluses defined as a systolic blood pressure less than 90mmHg. Normotensive patients who require fluid therapy with any other manifestation of low perfusion including tachycardia, low urine output, increased core-peripheral temperature gradient, serial increase in serum lactate, and serial increase in base deficit, and normotensive). The endpoint of fluid resuscitation is return normal blood pressure Exclusion Criteria: -1. Contraindication for fluid administration including acute pulmonary edema. 2. Moderate or more tricuspid valve lesion or pulmonary hypertension (more 50 mmHg) where high central venous pressure is expected 3. Patients on hemodialysis. 4. Patient on intra-aortic balloon pump (IABP) or extracorporeal membrane oxygenation (ECMO) 5. Irregular cardiac rhythm: patients with atrial fibrillation or frequent ectopics are excluded. 6. Patients with chest open 7. Poor echocardiography window (The images will be stored and analyzed by senior physician within the ICU certified in echocardiography)

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| All patients<br>The IVC will be measured by the automated mode and manual measures will be recorded. All patients will have PPv by LiDCO | Diagnostic Test: Automated echocardiographic inferior vena cava measurement<br>* Patients will be place in supine position. view: subcostal view, importantly supine is standard position for IVC measurement, the IVC is larger in the right lateral decubitus position and vice versa, alternatively directly through a transhepatic approach. Measures will be performed in the two dimensional mode close to the hepatic vein (1 - 3cm from the IVC connection to the right atrium). The IVC will be measured by MM-Mode manually and with the automated mode (both measures will be recorded. In the manual mode this measure requires concurrent utilization of M-Mode and two dimensional mode<br>* Other names: LiDCO;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fluid responsiveness rate 500cc of colloids over 10 min. | defined as increase in the stoke volume by 15% after infusion of 500cc of colloids | 30 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| HR | before and after the fluid challenge | 30 minutes | 
| MAP | before and after the fluid challenge | 30 minutes | 
| VTI | before and after the fluid challenge | 30 minutes |