Posterior quadratus lumborum block versus epidural analgesia for postoperative pain management after open radical cystectomy: A randomized clinical trial

Background: In open abdominal surgery, continuous epidural analgesia is commonly used method for postoperative analgesia. However, ultrasound (US)-guided fascial plane blocks may be a reasonable alternative.

Methods: In this randomized controlled trial, we compared posterior quadratus lumborum block (QLB) with epidural analgesia for postoperative pain after open radical cystectomy (ORC). Adult patients aged 18-85 with bladder cancer (BC) scheduled for open RC were randomized in two groups. Exclusion criteria were complicated diabetes mellitus type I, lack of cooperation, and persistent pain for reasons other than BC. In one group, a bilateral US-guided single injection posterior QLB was performed with 3.75 mg/ml ropivacaine 20 ml/side. In the other group, continuous epidural analgesia with ropivacaine was used. Basic analgesia was oral paracetamol 1000 mg three times daily, and long-acting opioid twice daily in both groups. All patients had patient-controlled rescue analgesia with oxycodone. Postoperative cumulative rescue opioid consumption was recorded for the day of surgery, and the following 2 postoperative days (POD 0-2). Secondary outcomes were postoperative pain and nausea and vomiting.

Results: In total, 20 patients (QLB), and 19 patients (epidural analgesia) groups, were included in the analyses. Cumulative rescue opioid consumption on POD 0, being of duration 9-12 h, was 14 mg (7.6-33.3) in the QLB group versus 6.1 mg (2.0-16.1) in the epidural analgesia group, p = 0.089, and as doses, 8 doses (3.6-15.7) versus 4 doses (1.3-8.5), p = .057. On POD 1 consumption was 25.3 mg (11.0-52.9) versus 18.0 mg (14.4-43.7), p = .749, and as doses 12 (5.5-23.0) versus 10 (8-20), p > .9, respectively. On POD 2 consumption was 19.1 mg (7.9-31.0) versus 18.0 mg (5.4-27.6) p = .749, and as doses 8.5 (5.2-14.7) versus 11 (3.0-18.0) p > .9, respectively.

Conclusion: Opioid consumption did not differ significantly between posterior QLB and an epidural infusion with ropivacaine for the first 2 postoperative days following RC.

Trial registration: ClinicalTrials.gov identifier NCT03328988.