A prospective, multiple-center, double-blinded, randomized, controlled clinical study to evaluate the antalgic effects between distal-proximal acupoints combination and regional acupoints combination stimulated with electroacupuncture on patients undergoing Off-Pump Coronary-Artery Bypass Grafting(OP-CABG).This clinical trial is to investigate whether electroacupuncture(EA) anesthesia can reduce analgesic in OP-CABG surgery in distal-proximal group.The origins of therapeutic acupuncture can be traced back at least 2,500 years in China. There has been an explosion of interest in Western medicine within the United States and Europe in application of acupuncture technique. Acupuncture enjoys worldwide acceptance for treating diseases such as migraine, chronic low back pain, and knee osteoarthritis. In 2002, WHO recommended 107 symptoms, syndromes, and diseases definitively shown to be effectively treated by acupuncture. Coronary heart disease (angina pectoris) is among these pathologies. A recent clinical trial demonstrated an acupuncture-assisted anesthesia strategy reduces postoperative morbidity and medical costs in open-heart surgery under cardiopulmonary bypass. Previous researches in animal models have demonstrated that electroacupuncture pretreatment protects the heart from ischemic injury. The investigators observed that electroacupuncture pretreatment (EAP, 30-minute electric stimulation through 4 electrodes attached to the bilateral forearm acupoints) before surgery significantly attenuated serum troponin levels during and shortly post-surgery in adult heart valve replacement patients and children undergoing cardiac surgery correcting congenital heart malformation.However, whether electroacupuncture anesthesia may reduce analgesic in OP-CABG surgery,especially in different combination of acupoints,has never been previously investigated.

The anesthesia will be performed in a standard way. The propofol and sufentanil will be infused in target-controlled infusion mode. The dosage of analgesic will be assessed by the consumption of sufentanil. And the electroacupuncture anesthesia will be implemented by a device named "Hua Tuo" electronic acupuncture treatment instrument.

Inclusion Criteria:

• American Society of Anesthesiologists I-III
• Scheduled for Off-Pump Coronary-Artery Bypass Grafting surgery
• First thoracotomy
• Signed written informed consent obtained

Exclusion Criteria:

• American Society of Anesthesiologists IV
• Undergoing surgery within 12 h of admission to hospital
• Life expectancy < 1 year at the time of enrollment
• Hemodynamic instability as defined by a systolic blood pressure <90 mmHg
• Preoperative Intra-aortic Balloon Pumping or Ventricular Assisted Device
• Severe hepatic or renal dysfunction
• Not the first thoracotomy
• Mediastinal fiber thickening or severe pleural adhesions
• Severe adverse reactions
• Severe systemic infection
• With contraindications to the use of electroacupuncture, such as skin damage or infection at the acupoints
• Suffering from nervous system disease or abnormal mental state
• Participate in the other clinical trial 3 month before the enrollment