Echocardiographic Evaluation of the Change on Pulmonary Blood Flow and Cardiac Function During One-lung Ventilation

Study Overview
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Brief Summary
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The investigators used transesophageal echocardiography (TEE) to assess the change of pulmonary blood flow and bi-ventricular function during lung isolation. The investigators hypothesized that changes in pulmonary venous flow with lung isolation may be related the shunt fraction and oxygenation during one lung ventilation (OLV). The investigators also observed the cardiac function during two lung ventilation (TLV) and OLV in supine and lateral position by TEE.

Conditions
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Video-assisted Thoracic Surgery

Intervention / Treatment
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* Procedure: transesophageal echocardiography(TEE)


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 and II Thoracic surgical procedure (video-assisted) Exclusion Criteria: severe functional liver or kidney disease cardiac disease arrhythmia 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: one lung group<br> | Procedure: transesophageal echocardiography(TEE)<br>* Transesophageal echocardiography examination will be performed TLV in supine and lateral position, 10, 20 and 30 min during OLV in left lateral decubitus position. By using the transesophageal echocardiography, we will evaluate the changes of pulmonary blood flow and cardiac function.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The change of pulmonary blood flow | 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 | two-lung ventilation in the supine (T1) and lateral position (T2) and 10 (T3), 20 (T4), and 30 min (T5) during OLV in the left lateral decubitus position. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The changes of respiratory 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 | two-lung ventilation in the supine (T1) and lateral position (T2) and 10 (T3), 20 (T4), and 30 min (T5) during OLV in the left lateral decubitus position. | 
| The change of cardiac function |  | two-lung ventilation in the supine (T1) and lateral position (T2) and 10 (T3), 20 (T4), and 30 min (T5) during OLV in the left lateral decubitus position. |