36 adolescent patients undergoing corrective surgery for idiopathic scoliosis were randomly assigned to receive either low-dose ketamine or a placebo intra- and post-operatively. The purpose of this study was to compare postoperative morphine consumption, pain, nausea and vomiting, sedation scores, and antiemetic medication consumption between groups. The results indicated that ketamine significantly reduced morphine and antiemetic consumption at up to 48 hours when compared to placebo. The study groups did not differ in terms of pain, sedation scores, or incidence of nausea and vomiting.