Risk factors of patients with and without postoperative nausea (PON).

This purpose of this analysis was to study risk factors of postoperative nausea (PON) and their strength. Data were obtained during the screening phase of a controlled clinical trial of aromatherapy for PON. In a sample of 1151 postsurgical subjects, 301 (26.2%) reported PON. Significant risk factors identified in the order of odds ratios for nausea were female gender, gastrointestinal surgery, use of volatile anesthesia gases, history of PON, history of motion sickness, and use of opioids after surgery. Although still over 1.0, the risk factors of length of surgery over 1 hour and gynecologic surgery had the lowest odds ratios. Likelihood of nausea increased significantly with the number of significant risk factors (P<.0001). Administration of preventive antiemetic medication also increased with the number of significant risk factors (P<.0001). Among 301 subjects reporting nausea, 49 (16.28%) received preventive medication. Despite prevention efforts, PON remains a substantial side effect for many surgical patients.