Factors Associated With Rebound Pain After Patient-controlled Epidural Analgesia in Patients Undergoing Major Abdominal Surgery: A Retrospective Study

Objectives: Although patient-controlled epidural analgesia (PCEA) is an effective form of regional analgesia for abdominal surgery, some patients experience significant rebound pain after the discontinuation of PCEA. However, risk factors for rebound pain associated with PCEA in major abdominal surgery remain unknown. This study evaluated the incidence of rebound pain related to PCEA and explored potential associated risk factors.

Materials and methods: We performed a retrospective review of 236 patients using PCEA following hepatobiliary and pancreas surgery between 2018 and 2020 in a tertiary hospital in South Korea. Rebound pain was defined as an increase from well-controlled pain (numeric rating scale <4) during epidural analgesia to severe pain (numeric rating scale ≥7) within 24 hours of discontinuation of PCEA. Logistic regression analysis was performed to determine the factors associated with rebound pain.

Results: Patients were categorized into the nonrebound pain group (170 patients; 72%) and the rebound pain group (66 patients; 28%). Multivariable logistic regression analysis revealed that preoperative prognostic nutritional index below 45 (odds ratio=2.080, 95% confidential interval=1.061-4.079, P =0.033) and intraoperative transfusion (odds ratio=4.190, 95% confidential interval=1.436-12.226, P =0.009) were independently associated with rebound pain after PCEA discontinuation.

Discussion: Rebound pain after PCEA occurred in ~30% of patients who underwent major abdominal surgery, resulting in insufficient postoperative pain management. Preoperative low prognostic nutritional index and intraoperative transfusion may be associated with rebound pain after PCEA discontinuation.