Rhomboid Intercostal Block With Sub-Serratus Plane Block Versus Erector Spinae Block

This randomized controlled trial aims to evaluate the analgesic efficacy of two ultrasound-guided regional anesthesia techniques-Rhomboid Intercostal Block with Sub-Serratus Plane Block (RIB + SSP) and Erector Spinae Plane Block (ESB)-in patients undergoing Modified Radical Mastectomy (MRM) for breast cancer. Eighty female patients aged 18-65 years with ASA physical status II or III will be enrolled and randomly assigned to receive either RIB + SSP or ESB prior to surgery. Both blocks will be performed under ultrasound guidance 30-45 minutes before induction of general anesthesia. The primary outcomes are postoperative pain scores measured using the Visual Analog Scale (VAS) and total opioid consumption in the first 24 hours after surgery. Secondary outcomes include intraoperative and postoperative hemodynamic parameters, time to first analgesic request, total intraoperative opioid use, recovery time, patient satisfaction, and incidence of adverse effects such as nausea and vomiting. The study will be conducted at the National Cancer Institute - Cairo University from June 2025 to June 2026. Ethical approval will be obtained, and written informed consent will be collected. This study aims to identify the more effective and safer regional technique to improve postoperative recovery and reduce opioid dependence in breast cancer patients.