Application of ultrasound-guided anterior quadratus lumborum block approach at the lateral supra-arcuate ligament in elderly patients undergoing colorectal cancer surgery.

Objective: To investigate the anesthetic and analgesic effects of combining general anesthesia with an anterior quadratus lumborum block at the lateral supra-arcuate ligament (SA-AQLB) in elderly patients undergoing laparoscopic radical resection for colorectal cancer (CRC).

Methods: In this prospective study, 92 elderly patients scheduled for radical CRC resection were randomly divided into three groups: ultrasound-guided SA-AQLB group (SA group, n=31), ultrasound-guided subcostal AQLB (SC-AQLB) group (SC group, n=31), and a general anesthesia-only group (GA group, n=30). Measurements included mean arterial pressure (MAP) and heart rate (HR) at predefined time points, ranging from pre-operation to the end of surgery.