The Effect of Transmuscular Quadratus Lumborum Block on Postoperative Opioid Consumption in Patients Undergoing Percutaneous Nephrolithotomy: A Randomized Controlled Study

Background This study aimed to investigate the effect of ultrasound-guided transmuscular quadratus lumborum block (QLB) on postoperative opioid consumption in patients undergoing percutaneous nephrolithotomy (PCNL). Methodology A total of 40 patients aged between 18 and 60 who were classified as American Society of Anesthesiologists status I-II and scheduled for unilateral PCNL were randomly divided into two groups. Patients in Group QLB (n = 20) received a single-shot QLB with 20 mL of 0.25% bupivacaine in the preoperative period. No intervention was performed in the control group (Group C, n = 20). Dermatomes affected by the block procedure were evaluated in the preoperative period in the group of patients who were administered the block procedure. General anesthesia was administered to all patients in both groups. In the postoperative period, opioid consumption, pain scores, side effects related to opioid consumption, and additional analgesic requirements were recorded. Results Opioid consumption was significantly lower in Group QLB compared to Group C at all times (p < 0.05). Postoperative visual analog scale (VAS) scores during the movement were significantly lower in Group QLB compared to Group C at all times (p < 0.05). VAS scores at rest were reported to be significantly lower in Group QLB compared to Group C, except for the eighth and twelfth hours (p < 0.05). The requirement for additional analgesic agents was significantly lower in Group QLB compared to Group C (p < 0.05). Conclusions QLB reduced postoperative opioid consumption and VAS scores by providing more effective analgesia compared to the control group in patients who underwent PCNL.