 The study will include patients, male and female, between the ages of 3 months to 14 years of all ethnic and race groups. Patients with a history of clinically significant cardiovascular, pulmonary, hepatic, renal, neurologic, psychiatric or metabolic disease will be excluded. After obtaining consent from a legal guardian, patients will be randomly assigned to the placebo or treatment group. Both groups will receive rescue opioids for postoperative pain management via either patient-controlled analgesia PCA or nurse-controlled analgesia NCA administration for younger patients. The intraoperative anesthetic management will be standardized in all patients. 