Primary observation indices : ( 1 ) postoperative time and additional amount of morphine ; ( 2 ) rate of postoperative delirium ( POD ) and postoperative cognitive dysfunction ( POCD ) at 3 days , 1 week , 3 months and 6 months postoperation ( T1-T4 ) ; ( 3 ) se rum levels of NSE and S-100 were measured at the timepoints of before analgesia ( t0 ) , before anesthesia ( t1 ) , end of surgery ( t2 ) and 6 hours , 24 hours , 48 hours postoperation ( t3-t5 ) ; ( 4 ) other serious complications .