Effect of TEAS on PONV After Spinal Surgery

Inclusion Criteria:

* Male and female patients , 18 or older
* American Society of Anesthesiologists (ASA) classification I or II or III
* Undergoing elective spinal surgery expected to last no more than four hours (from induction of anesthesia to extubation).
* Capable and willing to consent

Exclusion Criteria:

* Neuraxial (intrathecal or epidural) block
* Significant ongoing history of vestibular disease or dizziness
* Nausea or vomiting within 24 hours prior to surgery, use of antiemetic or emetogenic drugs within 3 days of surgery
* Documented alcohol or substance abuse within 3 months before the surgery
* Limb abnormalities such as burn and amputation.
* Poorly controlled diabetes mellitus (fasting plasma glucose \>126 mg/dL or \<70 mg/dL)
* Implantation of metal/electrical devices, such as nerve stimulator, cardiac pacemaker, cardioverter, defibrillator and internal hearing aids
* Rash, local infection, keloid, any dermatologic condition that could interfere with the acupoint stimulation area
* Documented alcohol or substance abuse within 3 months before surgery
* Presence of clinically diagnosed major psychiatric condition such as bipolar disorder, uncontrolled major depression, or schizophrenia
* Chemotherapy or radiation therapy within 7 days before surgery
* Investigational product use within 3 months prior surgery
* Any condition, which in the opinion of the investigator would make subject ineligible for participation in the study (history of unstable cardiovascular, pulmonary, renal, hepatic, seizures)
* Special population (prisoners, pregnant and lactating women)