Inclusion Criteria:  age 60 to 80; ASA physical status score of I, II or III; Scheduled to undergo a posterior lumbar surgery; Ideal body weight≤80 kg;  Exclusion Criteria:  Those who are refused to be included; Those who are allergic to the drugs used in this study; Emergency operation Degree II or III atrioventricular block heart failure History of ALS, preexcitation or active dysrhythmia Severe liver injury (bilirubin > 1.46 mg/dl) Severe renal injury (creatinine clearance < 30 ml/min) or Renal failure History of epilepsy History of porphyria Preoperative hypotension (SBP< 90mmHg) Drug contraindications of NSAIDs Allergic to anaesthetic