AIM: To monitor the changes of total systemic vascular resistance (TSVR) and stroke volume (SV) during fluid therapy by transesophageal echo Doppler and to explore the correlation between TSVR and SV.

• 目的:应用经食管超声多普勒血液动力学监测仪,观察液体治疗时每搏量(SV)与全身血管阻力(TSVR)的变化,并分析两者的相关性。