Overview
This study compares two ultrasound-guided nerve block techniques for pain control after mastectomy for breast cancer: the pectoral nerve block (PECS II) and the serratus posterior superior intercostal plane (SPSIP) block. Both techniques involve injecting local anesthetic near nerves supplying the surgical area.
The study will include 78 adults aged 18 to 85 years undergoing elective mastectomy under general anesthesia. Participants will be randomly assigned to receive one of the two blocks before surgery. Both groups will receive postoperative pain treatment, including a patient-controlled device that delivers tramadol when needed.
The main aim is to compare postoperative opioid consumption. The study will also assess pain at rest and during movement, the need for additional pain medication, side effects, recovery quality, and persistent pain. Pain scores and tramadol consumption will be recorded at 0, 2, 4, 8, 16, and 24 hours after surgery. Recovery quality will be assessed at 24 hours, and persistent pain will be assessed by telephone at 3 months.
Description
This prospective, randomized study will be conducted at Bursa City Hospital in adults undergoing elective mastectomy for breast cancer. Participants will be assigned to an ultrasound-guided serratus posterior superior intercostal plane (SPSIP) block or a pectoral nerve block (PECS II) using a computer-generated randomization sequence.
Both blocks will be performed before induction of general anesthesia. The SPSIP group will receive 30 mL of 0.25% bupivacaine in the fascial plane between the serratus posterior superior and intercostal muscles at the third rib. The PECS II group will receive 10 mL of 0.25% bupivacaine between the pectoralis major and pectoralis minor muscles and 20 mL between the pectoralis minor and serratus anterior muscles.
General anesthesia and postoperative multimodal analgesia will be standardized. On arrival in the recovery room, participants will receive intravenous patient-controlled analgesia with tramadol at a concentration of 5 mg/mL, a bolus dose of 10 mg, a lockout interval of 20 minutes, and no basal infusion. Intravenous meperidine at 0.5 mg/kg will be administered as rescue analgesia when the Numeric Rating Scale (NRS) score is 4 or higher.
Postoperative pain and opioid consumption will be assessed by an anesthesiologist who is unaware of group allocation. The clinician performing the block will know the assigned technique and will not collect postoperative outcome data.
NRS scores at rest and during movement will be recorded at 0, 2, 4, 8, 16, and 24 hours after surgery. The scale ranges from 0 (no pain) to 10 (the worst pain imaginable). Tramadol consumption will be recorded at the same time points. Rescue analgesic requirements, time to first rescue analgesia, time to first postoperative mobilization, length of hospital stay, adverse effects, and block-related complications will also be recorded.
Quality of recovery will be assessed using the Quality of Recovery-15 questionnaire at 24 hours after surgery. Postoperative nausea and vomiting will be monitored during the first 24 hours. Persistent postoperative pain will be assessed at 3 months using the McGill Pain Questionnaire during a telephone interview conducted with prior participant consent.
Eligibility
Inclusion Criteria:
- Age between 18 and 85 years.
- Scheduled for elective mastectomy for breast cancer under general anesthesia.
- American Society of Anesthesiologists (ASA) physical status I, II, or III.
- Willingness to participate in the study and provide informed consent.
Exclusion Criteria:
- Refusal to participate in the study.
- History of bleeding diathesis or coagulopathy.
- Receiving anticoagulant therapy.
- Allergy or hypersensitivity to local anesthetics or opioid medications.
- History of local anesthetic toxicity.
- Infection at the planned block injection site.
- Hepatic or renal failure.
- Uncontrolled diabetes mellitus.
- Uncontrolled hypertension.
- Intellectual disability.
- Receiving opioid treatment for chronic pain.
- Pregnancy, suspected pregnancy, or breastfeeding.
- Planned bilateral mastectomy.


