Thoracic epidural block compared to intravenous morphine in the treatment of pain in hepatic post-embolization syndrome: a randomized controlled clinical trial

BACKGROUND: Hepatic transarterial embolization and chemoembolization are surgical procedures used to treat patients with hepatic tumors of primary and metastatic origin, however they cause significant pain in the postoperative period. The objective of the study was to compare thoracic epidural block with intravenous morphine in the treatment of pain in hepatic post-embolization syndrome. METHODS: A total of 50 patients undergoing hepatic transcatheter arterial embolization were randomized and allocated into two groups: intravenous morphine group (IG) underwent to a morphine dose in the operating room; and thoracic epidural block group (EG) underwent to a single-shot epidural injection. All patients used intravenous patient-controlled analgesia (PCA) in postoperative period. Intravenous morphine consumption in the postoperative period, pain measured by the numerical rating scale (NRS), length of hospital stay, nausea, vomiting, pruritus, urinary retention, respiratory depression and drowsiness were analyzed. RESULTS: There was no difference in the mean morphine consumption and NRS in the immediate postoperative (IPO) period. On postoperative day 1, the IG mean morphine consumption was 6.3 mg vs. 0.45 mg in EG, p<0.01. NRS in IG was 3.77 vs. 0.82 in EG, p<0.01. Morphine consumption in post-operative period in IG was 6.91 mg vs. 0.5 mg in EG, p<0.01. Only two patients in the EG were hospitalized for more than one day, while in the GV eight patients were discharged from the second postoperative day, however there was no statistically significant difference in the length of hospital stay. Pruritus was observed in 18.2% of EG patients and none in the IG, p = 0.04. CONCLUSIONS: Thoracic epidural block was superior to intravenous morphine in the treatment of pain in hepatic post embolization syndrome.