Key Determinants of Immediate Postoperative Pain, Nausea, and Vomiting in Orthognathic Surgery: Insights From a Retrospective Cohort Study.

Introduction Orthognathic surgery frequently leads to immediate postoperative pain (IPP) and postoperative nausea and vomiting (PONV), impacting patient recovery and satisfaction. This study aims to identify key determinants contributing to IPP and PONV following orthognathic surgery. Methods A retrospective cohort study was conducted involving patients who underwent orthognathic surgery at Kurume University Hospital between January 2020 and December 2023. Patients were divided into two groups: "mandible alone" and "bimaxillary." Independent variables, including patient-related, surgery-related, and anesthesia-related variables, were evaluated against IPP and PONV using multivariate logistic regression analysis. Results The study enrolled 181 patients who underwent orthognathic surgery with an average age of 26.6 ± 8.1 years (range: 16-54 years), of which 139 patients (76.8%) were women. Multivariate analysis identified low body mass index (BMI) as a common significant related factor for both IPP (adjusted odds ratio {OR}, 3.70; P= 0.0034) and PONV (adjusted OR, 2.80; P = 0.022). Inhalation anesthesia was significantly associated with IPP (adjusted OR, 9.07; P = 0.049), while higher blood loss and increased local anesthesia volumes were associated with PONV (adjusted OR, 0.35 and 0.31; P = 0.005 and 0.016, respectively). Conclusion BMI, total blood loss, anesthesia method, and the total amount of local anesthesia may be significant related factors of postoperative complications following orthognathic surgery. These findings can inform preoperative assessments and anesthesia management to improve patient outcomes.