Comparison of two approaches to quadratus lumborum block for postoperative analgesia in radical cystectomy: a randomized clinical trial.

Abstract

Background: The aim of this study was to evaluate the analgesic effects following radical cystectomy using two ultrasound guided quadratus lumborum block (QLB) techniques: anterior and intramuscular.

Methods: Sixty patients aged 40-60 years old with ASA I, II were considered for this study. They were divided into two equal groups. Bilateral ultrasound guided QLB was performed via either the anterior (QLBa) or intramuscular (QLBi) approach with 2.5 mg/kg of 0.25% bupivacaine diluted to 20 mL of normal saline after surgery. The primary outcome was the time to the first request for analgesia, while the secondary outcomes were the dose of postoperative morphine consumption, numerical rating scale (NRS) at rest and on movement, Bromage Scale, adverse events, and patient satisfaction.

Results: The mean time to first request for analgesia was significantly prolonged in group QLBa (14.7±1.33 hours) compared to group QLBi (9.8±0.72 hours) (P<0.001). NRS either at rest or on movement were not statistically significant until six hours postoperatively. At 10, 12, and 14 h, Group QLBi had a significantly higher NRS Score at rest and on movement (P<0.001). Group QLBa had a significantly lower total morphine consumption (5.37±0.49 mg) compared to Group QLBi (6.4±0.77 mg) (P<0.001). The QLBa had higher patient satisfaction than the QLBi.

Conclusions: Compared with QLBi, bilateral ultrasound guided QLBa provided a longer time to the first analgesic request, less postoperative opioid consumption, lower NRS at rest and on movement, and higher patients' satisfaction after radical cystectomy under general anesthesia.