Overview
This randomized, double-blind study will compare the effectiveness of three different volumes of serratus posterior superior intercostal plane block for postoperative pain control in patients undergoing unilateral breast surgery with axillary lymph node dissection. Ninety participants will be randomly assigned to receive 20 mL, 30 mL, or 40 mL of 0.25% bupivacaine.
The primary outcome is total tramadol consumption during the first 24 hours after surgery. Pain scores, time to first analgesic request, rescue analgesic use, quality of recovery, postoperative nausea and vomiting, block success, and block-related complications will also be evaluated.
Eligibility
Inclusion Criteria:
- Aged 18 to 75 years
- American Society of Anesthesiologists physical status I-III
- Scheduled for elective unilateral breast surgery under general anesthesia
- Able to provide written informed consent
Exclusion Criteria:
- Refusal to participate
- Coagulopathy
- Known allergy to local anesthetics or a history of local anesthetic systemic toxicity
- Liver or kidney failure
- Uncontrolled diabetes mellitus
- Uncontrolled hypertension
- Cognitive impairment or inability to understand the study procedures
- Chronic pain requiring opioid therapy
- Current antidepressant use
- Neuropathic pain
- Infection at the block injection site
- Pregnancy, suspected pregnancy, or breastfeeding
- Clinically significant frailty


