Effects of SPSIP Block on Perioperative Inflammation and TLR4 in Breast Cancer Surgery

This study will investigate whether the serratus posterior superior intercostal plane (SPSIP) block improves postoperative recovery after breast cancer surgery. Participants will be randomly assigned to one of two groups. One group will receive an ultrasound-guided SPSIP block, while the other group will undergo a similar procedure without active medication (sham procedure). Both groups will receive standard general anesthesia and postoperative pain management. Postoperative pain intensity, need for additional pain medication, nausea and vomiting, length of hospital stay, and persistent pain at 3 months after surgery will be assessed. Blood samples collected before surgery and at predetermined postoperative time points will be used to evaluate the body's inflammatory response to surgery and innate immune system activity. These assessments will include toll-like receptor 4 (TLR4), an immune-system marker, and selected inflammatory markers. The main question of this study is whether the SPSIP block, compared with the sham procedure, reduces the surgery-related inflammatory response and improves postoperative pain outcomes.

Inclusion Criteria: * Female patients aged 18 to 85 years. * Scheduled for elective breast cancer surgery under general anesthesia. * American Society of Anesthesiologists (ASA) physical status I-III. * Able to provide written informed consent. Exclusion Criteria: * Refusal to participate or inability to provide informed consent. * Allergy or contraindication to the study local anesthetic. * Coagulopathy or ongoing anticoagulant treatment contraindicating regional anesthesia. * Infection at the planned injection site. * Pre-existing chronic pain condition or regular opioid use. * Inability to communicate pain scores or comply with study assessments.