Comparison of the Analgesic Effects of Two Quadratus Lumborum Blocks (QLBs), QLB Type II vs QLB Type III, in Caesarean Delivery: A Randomised Study

Abstract

Background Quadratus lumborum blocks (QLBs) are relatively novel regional anaesthesia techniques, and the efficacy of all three types of QLB for postoperative analgesia in caesarean delivery (CD) has been demonstrated in separate studies. The aim of the present study is to compare the analgesic efficacy of the QLB-II and QLB-III blocks performed at the end of surgery in patients undergoing spinal anaesthesia for CD. Methods We conducted a comparative, blinded, prospective, randomised and efficiency study. A total of 80 patients scheduled for elective CD under spinal anaesthesia were randomly allocated to receive either bilateral ultrasound-guided QLB-II or QLB-III block in a 1:1 ratio. The primary outcome was opioid consumption administered by a patient-controlled analgesia in the first 24 hours postoperatively. The secondary outcome of the study was pain intensity. Also, the time of first opioid requirement and the presence of nausea and vomiting were recorded. Results Morphine consumption was statistically significantly lower in the QLB-III group when compared with the QLB-II group at the 3rd, 6th, 12th and 24th hours (P < .001, P < .001, P = .004, and P = .015, respectively). The QLB-III group showed significantly lower pain scores at rest at the 1st, 3rd, 6th, 9th and 24th hours after surgery (P < .001, P < .001, P < .001, P = .007 and P < .001, respectively). The QLB-III group also showed significantly lower pain score on movement at all measurement times (P < .001). Conclusions The analgesic efficacy of QLB-III was superior to QLB-II in patients who had undergone CD under spinal anaesthesia without use of intrathecal opioids and nonsteroidal anti-inflammatory drugs.