Perioperative Rescue Transesophageal Echocardiography in Intensive and Critical Status

Study Overview
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Brief Summary
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We initiate this study to assess the diagnostic efficiency of PReTEE, a simplified TEE scan sequence with a combination of 3 valuable views of ME 4C, ME AV LAX and TG SAX, in identifying cardiac pathologies in the phase of difficult cardiopulmonary bypass separation among patients who will undergo high-risk cardiac surgical procedures.

Detailed Description
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There are 6 TEE operators who will participate in our trial, which is of restriction. Also, the participants we scheme to include are all junior TEE operators at our institute, who have already skilled at images obtainment and interpretation. Prior to the trial initiation, all these TEE operators will be randomly assigned into either the PReTEE group or the conventional TEE group with a 1:1 ratio (3 per group). Due to another limitation of eligible patients, TEE examinations thereby for patients are not conducted by equal numbers of operators stratified by groups. Furthermore, patients will be examined by 1-4 operators and 1 expert without removing the probe when separated from cardiopulmonary bypass. The ultimate sample size we calculate is 46 TEE examinations.

Official Title
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Establishment and Verification of Clinical Thinking Flowchart of Rescue Transesophageal Echocardiography in the Diagnosis and Treatment of Perioperative Patients in Intensive and Critical Status

Conditions
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Transesophageal Echocardiography

Intervention / Treatment
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* Diagnostic Test: The PReTEE group
* Diagnostic Test: The conventional TEE group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age of 18 yr and greater; High-risk cardiac surgery (one of the followings): Baseline left ventricular ejection fraction < 50%, Coronary artery bypass graft combined with valve procedures, Multiple valve procedures (≥ 2), Aortic root or arch involved, Euroscore > 6, Previous cardiovascular surgery Exclusion Criteria: Lack of patient consent; Esophageal pathology (stricture, tumor, perforation/laceration, ulcer or fistula, diverticulum); Hiatus hernia; Perforated viscus; Active/recent upper gastrointestinal (GI) bleed; Non-elective cardiac procedures; Preoperative mechanical cardiac support (ECMO, LVAD or IABP)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 100 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: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: The PReTEE group<br>Prior to clinical application of PReTEE, all participants designated must receive professional training. Within the given 120 seconds participants in the PreTEE group need to provide the leading cause with regard to difficult separation from cardiopulmonary bypass among high-risk cardiac surgical procedures. | Diagnostic Test: The PReTEE group<br>* Prior to clinical application of PReTEE, all participants designated must receive professional training. They need to receive lectures focusing on the clinical thinking flowchart of rescue transesophageal echocardiography, in conjuntion with the simulator-based training. The discriminating ability of PReTEE will be further assessed in real clinical scenario, that is, within the specified 120 seconds participants in the PreTEE group need to provide the leading causes with regard to difficult separation from cardiopulmonary bypass in high-risk cardiac surgical procedures. All examinations will be supervised by a TEE expert owning to safety considerations but without help in views acquirement or interpretation. After completion of study assessments, the TEE expert will perform a standard comprehensive TEE, the results of which was reported to the attending cardiac anesthesiologist in charge of the patient and the recorders.<br>|
| Active Comparator: The conventional TEE group<br>The routine intra-operative TEE examinations are performed within the given 120 seconds before patients are separated from the cardiopulmonary bypass. | Diagnostic Test: The conventional TEE group<br>* Before cardiopulmonary bypass separation, conventional TEE examinations will be performed within the specified 120 seconds. Then, the expert will also perform a standard comprehensive TEE; the leading cause should also be presented to the attending anesthesiologists and recorders.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time taken in seconds in seeking out the leading cause of difficult CPB separation. | Time will be recorded in rea-time fashion from the appearance of midesophageal 4 chamber view to the diagnose of leading cause of difficult CPB separation in both the PReTEE group and the conventional group. | From the time of appearance of midesophageal 4 chamber view until the time of discrimination of the leading cause of difficult separation from cardiopulmonary bypass by the TEE operator, assessed up to 120 seconds. | 
| The rate of successful diagnosis. | Following the completion of TEE assessment by operators in the PreTEE group or in the conventional TEE group, the TEE expert in our center will then perform a standard comprehensive examination. The TEE expert will also be required to provide the leading cause of difficult separation, which then be presented to the attending anesthesiologist and cardiac surgeons as the reference of therapeutic approaches. The successful diagnosis is defined as the agreement of cause between operators in the PreTEE group or in the conventional TEE group and the expert. | From the time of appearance of midesophageal 4 chamber view until the time of discrimination of the leading cause of difficult separation from cardiopulmonary bypass by the TEE operator, assessed up to 120 seconds. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Detection rate of hypovolemia | Reduction in the LV cavity indicates hypovolemia. | From the time of appearance of midesophageal 4 chamber view until the time of discrimination of the leading cause of difficult separation from cardiopulmonary bypass by the TEE operator, assessed up to 120 seconds. | 
| Detection rate of left ventricular outflow tract obstruction | The occurrence of SAM | From the time of appearance of midesophageal 4 chamber view until the time of discrimination of the leading cause of difficult separation from cardiopulmonary bypass by the TEE operator, assessed up to 120 seconds. | 
| Detection rate of regional wall motion abnormality | Regional wall motion is commonly classified as 1) normal or hyperkinetic, 2) hypokinetic (reduced thickening), 3) akinetic (absence of thickening), and 4) dyskinetic (systolic thinning or aneurysmal changes | From the time of appearance of midesophageal 4 chamber view until the time of discrimination of the leading cause of difficult separation from cardiopulmonary bypass by the TEE operator, assessed up to 120 seconds. | 
| Detection rate of left ventricular systolic dysfunction | Left ventricular systolic dysfunction can be assessed as a reduction in systolic function and an increase in diastolic dimension. | From the time of appearance of midesophageal 4 chamber view until the time of discrimination of the leading cause of difficult separation from cardiopulmonary bypass by the TEE operator, assessed up to 120 seconds. | 
| Detection rate of right ventricular systolic dysfunction | A TEE with a D-shaped LV on trans-gastric short axis view is suggestive of RV volume overload and systolic dysfunction | From the time of appearance of midesophageal 4 chamber view until the time of discrimination of the leading cause of difficult separation from cardiopulmonary bypass by the TEE operator, assessed up to 120 seconds. | 
| Detection rate of right ventricular outflow tract obstruction | The occurrence of pulmonary embolism, residual thrombus or tumor is seen in the RA/ RV, leftward shift of the interatrial septum or moderate to severe tricuspid regurgitation. | From the time of appearance of midesophageal 4 chamber view until the time of discrimination of the leading cause of difficult separation from cardiopulmonary bypass by the TEE operator, assessed up to 120 seconds. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Transesophageal Echocardiography, Surgery, Rescue