Ear Acupuncture Preventing Delayed Gastric Emptying.

Inclusion Criteria: * Patients who underwent pancreaticoduodenectomy; * No delayed gastric emptying or gastrointestinal obstruction before operation. * ECOG score 0-2; * No opioid analgesia or gastrointestinal motility drugs were administered for more than one week before operation. * Adequate blood cell counts were available during the screening period. * The blood biochemical indexes during screening period were as follows (48 hours before operation to 14 days before operation): AST (SGOT), ALT (SGPT) were less than or equal to the upper limit of 2.5 times normal value (ULN). Total bilirubin is less than or equal to 300 micromol/L. ULN serum creatinine is within the normal limit, or the level of serum creatinine is higher or lower than the normal value of institutions, but the calculated clearance rate is greater than or equal to 60 mL/min/1.73 m2. If the creatinine clearance rate is used, the actual body weight should be used to calculate the creatinine clearance rate (e.g. using the Cockroft-Gault formula). * Coagulation function is normal. * Male or non-pregnant and non-lactating women who were older than or equal to 18 years old signed the informed consent. If a female patient is of childbearing age (regular menstrual proof), the pregnancy test (such as serum beta-hCG) before the first study of drug administration must be negative. If patients are sexually active, they must agree to use contraceptive methods that researchers believe are adequate and appropriate during the study of drug administration. In addition, male and female patients must take contraceptive measures after treatment, as recommended by the product prescription information provided in the study manual. * The patient has been informed of the nature of the study and has agreed to participate in the study and signed an informed consent before participating in any research-related activities. * Ability to comply with research visits and other programme requirements Exclusion Criteria: * The patient did not receive standard pancreaticoduodenectomy. * Myocardial infarction, severe or unstable angina pectoris, coronary artery or peripheral artery bypass grafting, New York Heart Association (NYHA) grade III-IV heart failure, cerebrovascular accident, transient ischemic attack or epileptic seizure occurred within 30 days before operation. * Any condition that may impair patient safety or the integrity of research data, including serious medical risk factors, medical events, laboratory abnormalities or psychiatric disorders; * The patient's access to any other clinical study or to a trial of an interventional drug may interfere with the evaluation of this study procedure. * Patients are unwilling or unable to follow the research procedure; * Researchers do not think it is suitable for inclusion. * Acupuncture and moxibustion is currently used or used in the past 30 days. * Ear trauma or unhealed ear wound * Stainless steel allergists