Patients older than 65 years old are at higher risk of postoperative morbidity and mortality. With the increasing number of old patients scheduled for digestive surgery, exploring methods to decrease postoperative morbidity is very important. Noninvasive methods may be easier to clinically use. Transcutaneous electric acupoint stimulation (TEAS)has been proved to decrease need for general anesthetics during anesthesia, and to alleviate systemic inflammatory response. Considering the morbidity and mortality after surgery is closely related to use of anesthetics and inflammatory response,TEAS may be a good selection for improving postoperative outcomes.Among the postoperative complications, pulmonary complication and systemic inflammatory response syndrome is with higher incidence, so we will focus on these two complications in our study.