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 subgrouped 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.