Participants in this arm receive three interventions: (1) Traditional Chinese Medicine acupoint patch applied to bilateral Neiguan, Taichong, and Sanyinjiao four hours before surgery. The patch contains Angelica sinensis, Sinapis alba, Mosla chinensis, Cinnamomum cassia, and Corydalis yanhusuo. (2) Five-Element Music Therapy (predominantly Jiao mode) delivered via headphones from operating room entry until the end of surgery, with volume maintained at 40-60 decibels. (3) Standard local anesthesia protocol: intramuscular tramadol 100 mg half an hour before surgery plus intraurethral tetracaine perfusion for 10 minutes during surgery.

Participants in this arm receive standard local anesthesia only (intramuscular tramadol 100 mg half an hour before surgery plus intraurethral tetracaine perfusion for 10 minutes during surgery). A placebo acupoint patch (identical in appearance but containing no active ingredients) is applied to the same acupoints at the same time points. Participants wear headphones from operating room entry until the end of surgery but no music is played.

A topical herbal patch containing Angelica sinensis, Sinapis alba, Mosla chinensis, Cinnamomum cassia, and Corydalis yanhusuo. The patch is applied to bilateral Neiguan, Taichong, and Sanyinjiao acupoints four hours before surgery and removed two hours after surgery. The intervention aims to provide sustained analgesia, stabilize intraoperative vital signs, and reduce perioperative anxiety through transdermal absorption of active herbal components. This is an experimental intervention specific to the treatment arm.

Pain intensity measured by the Visual Analog Scale (VAS) at the time of ureteral access sheath placement (T2). The VAS is a 10-centimeter linear scale ranging from 0 (no pain) to 10 (worst possible pain). Participants mark their perceived pain level on the scale, and the score is recorded by a study nurse who is not involved in the surgical procedure. Higher scores indicate greater pain intensity.

Anxiety level assessed by the State Anxiety Inventory (S-AI) preoperatively (before entering the operating room) and postoperatively at 2 hours after surgery (T6, after returning to the ward). The S-AI consists of 20 items, each scored from 1 to 4, with total scores ranging from 20 to 80. Higher scores indicate greater anxiety. The scale is administered by a trained research assistant using standardized instructions.