Elderly patients have high mortality and postoperative complications rate after surgery,
especially postoperative cardiac complications. A meta-analysis revealed haemodynamic
intraoperative events significantly increased the risk of postoperative cardiac
complications.To limit the risk, optimize the intraoperative management of circulation is
essential. Anesthetic drug may effect on the haemodynamic intraoperative, reduction of
postoperative complications should aimed at choosing the optimal anesthetic drug with minimal
effect on haemodynamic.So this study is to explore the comparative efficacy and safety of
anesthetic drug (etomidate or propofol) in elderly patients