Effect of intraoperative vs. preoperative interpectoral-pectoserratus plane block on postoperative pain, analgesic use, shoulder range of motion, and muscle strength in breast cancer surgery

BACKGROUND: Pain following breast cancer surgery can slow recovery and limit shoulder range of motion (ROM). Recently, fascial plane blocks have gained attention for managing postoperative pain. The aim of this study was to compare the effects of intraoperative and preoperative interpectoral-pectoserratus plane (PECS) blocks on acute postoperative pain and early shoulder rehabilitation outcomes. METHODS: Patients undergoing breast cancer surgery were divided into three groups based on anesthesia type: general anesthesia + intraoperative PECS block (group 1, N.=23); general anesthesia + preoperative PECS block (group 2, N.=22); and general anesthesia only (group 3, N.=20). Postoperative pain was assessed using the Visual Analogue Scale (VAS). Shoulder ROM was measured with a goniometer and shoulder girdle muscle strength with a handheld dynamometer. At the 10-day follow-up of patients enrolled in a shoulder exercise program, in addition to VAS, ROM, and muscle strength measurements, disability was assessed using the Quick Disability of the Arm, Shoulder, and Hand (QuickDASH) questionnaire, depression with the Beck Depression Inventory (BDI), and Quality of Life with the Short Form-36 (SF-36). RESULTS: At 1- and 2-hours postsurgery, group 2 showed significantly lower VAS scores than the other groups (P<0.05). At 6, 12, and 24 hours, groups 1 and 2 had lower pain scores than the control group (P=0.05, P=0.001, and P=0.001, respectively), with no difference between them. On postoperative day 1, group 2 had significantly better shoulder abduction and flexion ROM, and greater extension strength (P=0.01, P=0.05, and P=0.001, respectively). On day 10, no significant difference was observed in ROM changes, but muscle strength improvements (abduction, extension, and flexion) remained significantly higher in group 2 (P=0.001, P=0.001, and P=0.004, respectively). Group 2 also had better QuickDASH and BDI scores (P=0.03 for both). CONCLUSIONS: Preoperative ultrasound-guided PECS block was more effective overall, while the intraoperative PECS block outperformed the control group in pain control, muscle strength, and Quality of Life measures.