Background: Minimally invasive repair of pectus excavatum (MIRPE) is now performed in adults.Managing adult patients' pain postoperatively has been challenging due to increased chest wall rigidity and the pressure required for supporting the elevated sternum. The optimal pain management regimen has not been determined. We designed this prospective, randomized trial to compare postoperative pain management and outcomes between thoracic epidural analgesia (TEA) and bilateral subcutaneous infusion pump catheters (On-Q). Methods: Patients undergoing MIRPE (modified Nuss) underwent random assignment to TEA or On-Q group. Both groups received intravenous, patient-controlled opioid analgesia, with concomitant delivery of local anesthetic. Primary outcomes were length of stay (LOS), opioid use, and pain scores. Results: Of 85 randomly assigned patients, 68 completed the study [52 men, 76.5%; mean (range) age, 32.2 (20.0-58.0) years; Haller index, 5.9 (range, 3.0-26.7)]. The groups were equally matched for preoperative variables; however, the On-Q arm had more patients (60.3%). No significant differences were found between groups in mean daily pain scores (P=0.52), morphine-equivalent opioid usage (P=0.28), or hospital stay 3.5 vs. 3.3 days (TEA vs. On-Q; P=0.55). Thirteen patients randomized to TEA refused the epidural and withdrew from the study because they perceived greater benefit of the On-Q system.Conclusions: Postoperative pain management in adults after MIRPE can be difficult. Both continuous local anesthetic delivery by TEA and On-Q catheters with concomitant, intravenous, patient-controlled anesthesia maintained acceptable analgesia with a reasonable LOS. In our cohort, there was preference for the On-Q system for pain management.