Echocardiographic Evaluation of the Change on Pulmonary Blood Flow and Cardiac Function Induced by Capnothorax During One Lung Ventilation

Study Overview
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Brief Summary
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Video-assisted thoracoscopic extended thymectomy (VATET) is a minimally-invasive method for excision of mediastinal mass instead of open thymectomy. The iatrogenic capnothorax with one-lung ventilation during VATET may cause hemodynamic instability due to the compression of intrathoracic structures. The purpose of this study is to evaluate the effects of capnothorax on the pulmonary blood flow and cardiac function during the VATET by using the transesophageal echocardiography.

Detailed Description
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Video-assisted thoracoscopic extended thymectomy (VATET) is a minimally-invasive method for excision of mediastinal mass instead of open thymectomy. The iatrogenic capnothorax with one-lung ventilation during VATET may cause hemodynamic instability due to the compression of intrathoracic structures. The purpose of this study is to evaluate the effects of capnothorax on the pulmonary blood flow and cardiac function during the VATET by using the transesophageal echocardiography

Official Title
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Echocardiographic Evaluation of the Change on Pulmonary Blood Flow and Cardiac Function Induced by Capnothorax During One Lung Ventilation

Conditions
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Mediastinal Tumors

Intervention / Treatment
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* Procedure: capnothorax


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Above 20 years of age. American Society of Anesthesiologists (ASA) Physical Status I, II, III. Thoracic surgical procedure (video-assisted thoracoscopic extended thymectomy ) Exclusion Criteria: Severe functional liver or kidney disease Diagnosed HF ( NYHA class >3) Arrhythmia or received treatment with antiarrhythmic drug . Exceed BMI > 30 kg/ m2 COPD Pathologic esophageal lesion (esophageal stricture or varix ) Pregnancy

Ages Eligible for Study
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Minimum Age: 20 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

Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: capnothorax group<br>After patient positioning, the capnothorax will be created by insufflation of carbon dioxide in patients undergoing video-assisted thoracoscopic extended thymectomy. | Procedure: capnothorax<br>* After patient positioning, the capnothorax will be created by insufflation of carbon dioxide in patients undergoing video-assisted thoracoscopic extended thymectomy.<br>* Other names: VATET, capnothorax, TEE;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The changes of the echocardiographic indices | pulmonary blood flow = PVA(cross sectional area of LUPV) x VTI(velocity time integral) x HR , Fractional area change = [(LVAd-LVAs)/LVAd] × 100 Ejection fraction = [(LVEDV(LV end-diastolic volume) -LVESV(LV end-systolic volume)/LVEDV] × 100 | four time points during the operation. (1)10 min after induction (baseline); (2) 1 min after CO2 insufflation; (3)10 min after of CO2 insufflation; and (4)20 min after CO2 insufflation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The changes of the oxygenation and respiratory dynamic parameters | shunt fraction Qs/Qt = (CcO2- CaO2)/(CcO2- CvO2) CcO2 = Hgb x 1.34 x ScO2 + PcO2 x 0.003, lung compliance : Compliance= Vt / Pplat, physiologic dead space : Vd/Vt = 1.14 x (PaCO2 - PETCO2)/PaCO2- 0.005 | four time points during the operation, an expected average of 3 hours. (1)10 min after induction (baseline); (2) 1 min after CO2 insufflation; (3)10 min after of CO2 insufflation; and (4)20 min after CO2 insufflation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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mediastinal mass, one-lung ventilation, capnothorax, transesophageal echocardiography