Epidural analgesia is not superior to systemic postoperative analgesia with regard to preventing chronic or neuropathic pain after thoracotomy

BACKGROUND: To assess prospectively the incidence of chronic and neuropathic pain in patients undergoing anteroaxillary thoracotomy with postoperative epidural analgesia or controlled-release oxycodone pain regimen. METHODS: 77 patients who underwent anteroaxillary thoracotomy were enrolled in our observational study. 40 patients received postoperatively a standardized oral analgesic protocol with controlled-release oxycodone and IV non opioid (CRO Group), and 37 patients received epidural analgesia with ropivacaine 0.1% + 1 μg/ml sufentanil (EDA Group) and IV non opioid. The painDETECT questionnaire was completed from the patients with one of the authors (JL) on the 7th postoperative day and six months postoperatively. RESULTS: The data of 60 patients were eligible for statistical analysis, 28 patients in the CRO Group and 32 patients in the EDA Group. 17 patients did not reach the 6-months follow-up interval (12 drop outs in the CRO Group and 5 drop outs in the EDA Group). 79% percent of patients in the CRO Group and 74% percent of patients in the EDA Group had a numeric rating scale score (NRS) = 0 after 6 months. 22% percent of patients in the CRO Group and 16% percent of patients in the EDA Group experienced a NRS 1–3 6-months postoperatively. No patient in the CRO Group and 9% percent of patients in the EDA Group had 6-months postoperatively a NRS 4–6. Neither in the CRO Group nor in the EDA Group we could detect a neuropathic pain 6 months postoperatively corresponding to a painDETECT score > 18. Overall, with regard to NRS, there was no statistical difference between the two groups (p = 0.13). 90% percent of patients in the CRO Group and 90% percent of patients in the EDA Group showed 6-months postoperatively a painDETECT score < 13 (definitely no neuropathic pain), and 9% percent in the EDA Group and 11% in the CRO Group had a 6-months painDETECt score 13–18 (p = not significant). CONCLUSION: These pilot data indicate that epidural analgesia is not superior to systemic postoperative analgesia with regard to preventing chronic or neuropathic pain after thoracotomy.