This randomized clinical trial aims to evaluate and compare the analgesic efficacy of the Serratus Posterior Superior Intercostal Plane (SPSIP) and Rhomboid Intercostal Block in patients undergoing Breast Cancer Surgery With Axillary Lymph Node Dissection. The primary outcome is Visual Analog Scale (VAS) during the first 24 hours after surgery. Secondary outcomes include total opioid consumption, requirement for rescue analgesia, block performance time, block-related and systemic side effects (hematoma, pneumothorax, local anesthetic toxicity, vascular puncture, infection), Patient satisfaction assessed using a Likert scale, quality of recovery assessed using the QoR-15 questionnaire.
Female patients aged 18-65 years
ASA physical status I-III
Scheduled for elective breast cancer surgery with axillary lymph node dissection
Body mass index (BMI) between 18 and 35 kg/m²
Refusal to participate
Allergy to local anesthetics
Infection at the injection site
Coagulopathy or ongoing anticoagulant therapy