Difference Between Central and Peripheral Arterial Blood Oxygen Saturation With Different CPB Strategy

Femoro-femoral cardiopulmonary bypass with retrograde perfusion is needed for totally thoracoscopic cardiac surgery. one of the major complication of retrograde perfusion is organ hypoperfusion. Arterial blood gas analysis can help to detect hypoperfusion or hypoxia during retrograde perfusion. However,whether the arterial oxygenation status from different parts of the body are the same in the condition of retrograde perfusion have not been studied. The present study is aimed to determine if there is difference in the arterial oxygenation between peripheral arterial and aortic root during the period of retrograde perfusion.In addition, the impact of artificial ventilation on the difference of arterial oxygenation will also be investigated.