Construction and evaluation of a PONV prediction model in patients undergoing orthopedic surgery under spinal anesthesia: a prospective cohort study

Postoperative nausea and vomiting (PONV) is a common complication following anesthesia. Most existing studies have focused on patients undergoing non-orthopedic surgeries with general anesthesia, neglecting the occurrence of PONV in patients receiving spinal anesthesia. This study aims to investigate the potential risk factors for PONV in patients undergoing orthopedic surgery with spinal anesthesia through a prospective cohort study and to construct and evaluate a clinical prediction model. Relevant factors associated with PONV in patients undergoing elective orthopedic surgery with spinal anesthesia from March11,2024, to October5,2024, were collected based on a literature review and clinical experience. Univariate and multivariate logistic regression analyses were conducted to identify potential predictive factors and construct a clinical prediction model. The model was evaluated using receiver operating characteristic (ROC) curves, calibration plots, and decision curve analysis (DCA), and was ultimately visualized using a nomogram. A total of 765 patients were ultimately included in this study, with a PONV incidence of 32.8% (251 cases). Multivariate logistic regression analysis revealed that female gender (OR = 2.51,95%CI:1.55–4.06, P < 0.001), a history of PONV (OR = 3.13,95% CI:1.73–5.67, P < 0.001), and preoperative pain scores (OR = 1.46,95% CI:1.08–1.98, P = 0.013) were independent predictive factors for PONV in patients undergoing orthopedic surgery with spinal anesthesia. Although non-smoking history, motion sickness history, preoperative high anxiety, and prolonged fasting did not demonstrate statistical significance, the study integrated these seven indicators based on clinical relevance to successfully construct a nomogram. The incidence of PONV is relatively high in patients undergoing orthopedic surgery with spinal anesthesia. Female gender, a history of PONV, and preoperative pain scores are identified as independent risk factors for the occurrence of PONV. The nomogram model constructed based on these factors demonstrates good predictive performance and clinical utility, aiding clinicians in the early identification of high-risk patients and the implementation of preventive strategies. This study was registered on April 23, 2024, in the Chinese Clinical Trial Registry (Registration Number ChiCTR2400083373).This trial is retrospectively registered.