Department of Anesthesiology, Qianfo Mountain Hospital of Shandong University, Jinan, China.;
Department of Clinical Medicine, Shandong University, Jinan, China;
Department of Orthopedics, Qilu Hospital of Shandong Uni- versity, Jinan, China;
Stroke; Volume; Variations; Heart-Lung; Sternotomy; Monitoring; Functional; Hemodynamic; Cardiac; Surgery;