Epidural analgesia versus oral morphine for postoperative pain management following video-assisted thoracic surgery: A randomised, controlled, double-blind trial.

Abstract

The use of thoracic epidural analgesia for postoperative pain management in video-assisted thoracic surgery (VATS) is controversial. Still, the evidence on omitting it in favour of systemic opioids is inconclusive, and studies are small and non-blinded. We aimed to compare pain after VATS using epidural analgesia or enteral opioids for postoperative pain management. A randomised, double-blind, controlled trial at a Danish tertiary hospital. Adult patients scheduled for VATS were assigned to multimodal non-opioid baseline analgesia supplemented with either thoracic epidural analgesia (TE Group) or oral morphine (OM Group) for postoperative pain management. We recorded pain five times a day, both at rest and during activity, using the Numeric Rating Scale (NRS) and categorised it into "acceptable pain" or "unacceptable pain". Unacceptable pain was defined as NRS (at rest) ≥3 or NRS (with activity) ≥5 when supplementary analgesics were given. The primary outcomes were the proportions of patients experiencing "unacceptable pain" during the postoperative period and the use of intravenous "rescue" opioids. Of the 161 included patients, 146 received the allocated treatment and their data were analysed. At rest, 34% of patients in the TE Group and 64% of patients in the OM Group experienced unacceptable pain during the study period, a significant between-group difference of 30% ( P < 0.0005). During activity these percentages were 32% of patients in the TE Group and 59% in the OM group, a difference of 27% ( P < 0.005). The median intravenous rescue morphine consumption during the study period was 4.5 [interquartile range (IQR), 0-10.0] mg in the TE Group and 7.5 [0-19.0] mg in the OM Group ( P < 0.005). Epidural analgesia provided better pain relief after VATS than oral morphine. The between-group difference in rescue intravenous morphine consumption was statistically significant but clinically irrelevant. ClinicalTrials.gov (NCT02359175).