Effects of anterior quadratus lumborum block versus erector spinae plane block on postoperative acute pain in percutaneous nephrolithotomy: a prospective, observational study

The study aimed to compare the pain-relieving effectiveness of anterior quadratus lumborum block (QLB3) and erector spinae plane block (ESPB), both of which have been documented to provide relief during abdominal surgery.

This prospective observational study, conducted between February and July 2023, included 96 patients who had undergone percutaneous nephrolithotomy (PCNL). Patients were divided into three groups: QLB3, ESPB, and control (no block) and received the corresponding nerve block in the preanesthetic room for regional block. Cumulative morphine consumption during the initial 24 h after PCNL, numerical rating scale resting/movement scores, intraoperative remifentanil usage, rescue analgesic requirements, time when the first analgesic was requested, and postoperative nausea and vomiting scores were documented and compared between the groups.

Total median morphine consumption in the first 24 h postoperatively was similar in the QLB3 and ESPB groups but higher in the control group (QLB3, 7 mg [(Q1-Q3) 7–8.5]; ESPB, 8 mg [6.5–9]; control, 12.5 [10–17]; P < 0.001). Similarly, median intraoperative remifentanil consumption did not differ between the block groups but was higher in the control group (QLB3, 1082 µg [IQR 805.5–1292.7]; ESPB, 1278 µg [940.2–1297.5]; control, 1561 µg [1315–2068]; P < 0.001). The number of patients receiving rescue analgesic medication was similar in the block groups but higher in the control group (QLB3, n = 9 [30%]; ESPB, n = 14 [46.7%]; control, n = 21 [70%]; P = 0.008).

QLB3 and ESPB were adequate and comparable in providing postoperative analgesia as part of multimodal analgesia after PCNL.

The study was registered on ClinicalTrials.gov (Identifier: NCT05822492).