Rebound pain after patient-controlled epidural analgesia for major abdominal surgery : a retrospective study

Background Rebound pain (RP) is recognized after locoregional analgesia, yet its incidence and determinants remain insufficiently characterized in major abdominal oncologic surgery patients managed with patient-controlled epidural analgesia (PCEA).Methods We conducted a retrospective single-center study of patients undergoing major abdominal oncologic surgery with PCEA (n = 199). Maximal Daily Pain Scores (MDPS) were recorded during and after PCEA withdrawal. RP was defined as an increase of ≥3 points on the 11-point Numeric Rating Scale within 8 hours of discontinuation. Data on timing, modality, and prescriptions of systemic relay analgesics were collected. Descriptive, univariate, and multivariate logistic regression analyses evaluated risk factors for RP.Results Of 199 patients, 92(46%) developed RP within 8 hours after PCEA withdrawal. Median PCEA duration was shorter in RP patients (93.3 h) compared with non-RP patients (112.5 h); p = 0.001, despite most receiving anticipatory relay prescriptions. Longer PCEA duration remained independently associated with a lower risk of RP in multivariate analysis (OR 0.81 per 12-hour increase; 95%CI,0.70–0.92; p = 0.002). The choice of relay analgesia was significantly associated with pain intensity during the two days before PCEA discontinuation, suggesting possible confounding by indication.Conclusion RP affected nearly half of patients after PCEA withdrawal. Extended PCEA duration significantly reduced its incidence.