Incidence and Risk Factors of Moderate to Severe Postoperative Pain Following the Placement of Primary and Secondary Orbital Implants: A Prospective Observational Study.

PURPOSE: To prospectively explore the incidence and risk factors of moderate to severe pain after primary and secondary orbital implantation following evisceration or enucleation surgery. METHODS: One hundred eighteen patients under general anesthesia for orbital implantation were enrolled in this study. In 91 patients, primary orbital implantation followed evisceration, and in 27 patients, the implantation was secondary after previous evisceration or enucleation surgery. Medical interventions for all participants were followed by standardized surgical, anesthetic, and analgesic protocols. Postoperative pain (POP) intensity was quantified by an 11-point numerical rating scale within 72 hours after the surgery, numerical rating scale >/=4 was considered moderate to severe POP. Multivariate logistic regression was utilized to identify the risk factors related to the development of POP. RESULTS: Thirty-five patients (29.7%) displayed moderate to severe POP, particularly within 6 to 24 hours after surgery, which peaked at 24 hours. Of these patients, 26 patients who were unable to tolerate the pain received additional doses of analgesics during in-hospital stay. Logistic regression model revealed that preoperative anxiety (odds ratios = 4.890; p = 0.002), congenital microphthalmia (odds ratios = 14.602; p = 0.038), and surgical time longer than 60 minutes (odds ratios = 5.586; p = 0.001) were significantly associated with moderate to severe POP after orbital implantation. CONCLUSIONS: Orbital implantation after evisceration or enucleation surgery is likely to cause moderate to severe pain intensity in the early postoperative period. Preoperative anxiety, prolonged surgical time, and congenital microphthalmia were the risk factors.