Epidural Against Systemic Analgesia An International Registry Analysis on Postoperative Pain and Related Perceptions After Abdominal Surgery

Background: The PAIN OUT registry collected data from > 30,000 patients on pain on the first postoperative day in hospitals worldwide. Utilizing the database, we compared systemic and epidural analgesia (EA) on postoperative pain and related side-effects in patients after abdominal surgeries (ASs). Methods: ASs were identified through the ICD9-Code and sub-grouped into laparoscopic surgery and open surgery. After identifying patients in this subset with and without EA, propensity-score matching was performed on the basis of demographics and comorbidities. Primary outcomes were different qualities of pain, and secondary outcomes were pain-related sensations and treatment-related side effects measured with the numeric rating scale. They were calculated as the risk ratio (RR) using the median as the divisor. Results: The database contained 29,108 cases, with 5365 AS, and 646 cases remained after matching. A risk analysis revealed that for the AS group, EA posed a significantly lower risk for the perception of worst pain (RR, 0.75; confidence interval [CI], 0.64-0.87), least pain (RR, 0.61; CI, 0.5-0.75), time in severe pain (RR, 0.61; CI, 0.5-0.75), in-bed activity interference of pain (RR, 0.71; CI, 0.59-0.85), pain interference with coughing (RR, 0.68; CI, 0.57-0.82) or sleeping (RR, 0.73; CI, 0.61-0.87), and a higher chance of pain relief (RR, 1.5; CI, 1.23-1.83). The risk for itchiness (RR, 2.23; CI, 1.62-3.07) appeared to be higher, as did the probability of satisfaction (RR, 1.25; CI, 1.03-1.51). The risk for feeling helpless (RR, 0.83; CI, 0.7-0.99) and drowsiness (RR, 0.74; CI, 0.63-0.88) was reduced. Both subgroups showed similar tendencies. Discussion: Regarding the pain intensity, satisfaction, and relatable side-effects, EA seems to be superior compared with systemic analgesia after AS.