Randomized clinical trial of abdominal wound catheters (AWC) versus epidural analgesia (EP) following open liver resection (OLR): an interim analysis

Abstract

Background: To compare outcomes following OLR between patients receiving EP vs AWC plus PCA (morphine). This is the mid-point analysis of a RCT powered to detect a difference in hospital length of stay. Methods: Patients undergoing OLR were randomized 1:1 to receive EP or AWC/PCA for 60 hours within an enhanced recovery protocol (ERAS). Postoperative variables recorded included pain scores and peak flow twice a day, need for ionotropic support, intravenous fluid requirements and length of stay amongst others. Results: Between April 2015 and January 2017 45 patients were randomized to EP (n=25) or WC (n=20). No differences were noted in pre-operative variables including age, sex, ASA grade, diagnosis, resection type and wound length. EP patients required more inotropic support in theatre (52% v 35%, ns), immediately postoperatively on day 0 (52% vs 20%, p=0.028 and day 1 (20% v 5%, ns). Accordingly, mean HDU stay was longer in patients with EP (1.6 days v 0.9, ns). No significant differences were noted in pain scores between the two groups except at Day 0 (EP 0 (0-8) vs WC 3 (0-6), p=0.004). Peak flow measurements, intravenous fluid requirements and overall length of stay were similar in both groups. Conclusion: The utilization of AWC was not inferior to EP in OLR. EP-associated hypotension translates into a greater need for ionotropic support when compared with WC following open liver resection. Whether this leads to a longer length of hospital stay remains to be seen.