Inclusion Criteria:  scheduled for elective laparoscopic major abdominal surgeries; ASA class II-III  Exclusion Criteria:  - 1- Patients with severe infection or diseases in respiratory system 2- Patients with severe arrhythmia or bradycardia 3- Patients with severe diseases in liver, kidney, endocrine or immune system. 4- Patients with history of uncontrolled hypertension, A-V conduction block. 5- Patients who had administrated the α-adrenergic agonists or β-receptor antagonist.  6- Patients who received the chemotherapy, radiotherapy, or immunotherapy within one month before operation 7- Patients who had feverbefore operation