PECS II vs. MTP for Analgesia After MRM

Ultrasound-Guided Modified Pectoral Plane (PECS II) Block Versus Midpoint Transverse Process to Pleura (MTP) Block for Postoperative Analgesia of Modified Radical Mastectomy

This randomized controlled study aims to compare the analgesic efficacy of the ultrasound-guided modified pectoral nerve block (PECS II) and the midpoint transverse process to pleura (MTP) block in female patients undergoing modified radical mastectomy (MRM). Postoperative pain intensity will be assessed using the Visual Analog Scale (VAS) over the first 24 hours, with additional evaluation of opioid consumption and complications.

Study Overview

• Status: Completed
• Conditions: Breast Neoplasm Female; Postoperative Pain Management
• Intervention / Treatment: Procedure: PECS II BLOCK; Procedure: MTP BLOCK

Detailed Description

Modified radical mastectomy (MRM) is associated with significant postoperative pain, which may increase opioid use, delay recovery, and contribute to chronic post-mastectomy pain syndrome. This study compares two regional analgesic techniques: the ultrasound-guided modified pectoral nerve block (PECS II) and the midpoint transverse process to pleura (MTP) block.

The PECS II block involves the injection of local anesthetic between the pectoralis minor and serratus anterior muscles, targeting the pectoral nerves and lateral cutaneous branches of intercostal nerves (T2-T6). It is widely used for anterior chest wall analgesia after breast surgery. The MTP block, a more recent paravertebral-domain technique, deposits anesthetic midway between the transverse process and the pleura, allowing spread to dorsal and ventral rami via the superior costotransverse ligament and potentially achieving broader thoracic segment coverage.

This randomized trial evaluates postoperative pain control using the Visual Analog Scale (VAS) over 24 hours, along with opioid consumption and adverse events. The aim is to determine whether the MTP block offers superior analgesia and an opioid-sparing effect compared to the PECS II block.

• Study Type: Interventional
• Enrollment (Actual): 88
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Egypt
  • Cairo, Egypt
    • Ain Shams University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Female patients scheduled for modified radical mastectomy (MRM).
2. Age between 40 and 65 years.
3. American Society of Anesthesiologists (ASA) physical status I-II.

Exclusion Criteria:

1. Known allergy to local anesthetics.
2. Coagulopathy.
3. Infection at the site of injection.
4. Patient refusal.
5. Inability to understand or use the pain scale.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: PECS II block group; Forty-four female patients (ASA I-II, 40-65 years) scheduled for modified radical mastectomy received an ultrasound-guided PECS II block with 20 mL of 0.25% bupivacaine (10 mL between pectoralis major and minor; 10 mL between pectoralis minor and serratus anterior).	Procedure: PECS II BLOCK; In the supine position, as described by Blanco et al., the ultrasound probe was placed transversely beneath the clavicle. After identifying the intermuscular plane between the pectoralis major and minor, 10 mL of 0.25% bupivacaine was injected. The probe was then repositioned laterally to identify the plane between the pectoralis minor and serratus anterior at the third to fourth ribs, where a further 10 mL of 0.25% bupivacaine was injected.
Active Comparator: MTP block group; Forty-four female patients (ASA I-II, 40-65 years) scheduled for modified radical mastectomy received an ultrasound-guided midpoint transverse process to pleura (MTP) block with 20 mL of 0.25% bupivacaine (10 mL injected at T2 and 10 mL at T6).	Procedure: MTP BLOCK; The block was performed with the patient in a seated position. The ultrasound probe was positioned parasagittally, approximately 3 cm lateral to the midline, at the T2 and T6 vertebral levels. A 22-gauge needle was advanced in-plane to the midpoint between the transverse process and pleura, and 10 mL of 0.25% bupivacaine was injected at each level. This protocol was adapted from the original technique described by Bhoi et al., with modifications in injection levels and volume.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Post-operative Pain Severity Assessed by VAS at Hour-4	Visual Analogue Scale is a scale for pain assessment ranging from 0 to 10 where 0 is minimum and means no pain while 10 is maximum and means maximum pain which means worse outcome	will be evaluated at hour-4 postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time of First Rescue Analgesia	Comparison between both groups regarding the time of first needed dose of nalbuphine	24 hours postoperatively
Cumulative Post-operative Nalbuphine Consumption in the First 24 Hours	Comparison between both groups regarding total consumed nalbuphine in first 24 hours postoperative	24 hours postoperatively
Incidence of Postoperative Side Effects and Complications	Comparison between both groups regarding postoperative side effects and complications	24 hours postoperatively
Post-operative Pain Severity Assessed by VAS on Admission to Postanesthesia Care Unit (PACU), at Hour-2, Hour-8, Hour-12, Hour-18 and Hour-24.	Comparison between postoperative pain severity after 2 hours, 4 hours, 8 hours, 12 hours, 18 hours and 24 hours postoperative between both groups using visual analogue score Visual Analogue Scale is a scale for pain assessment ranging from 0 to 10 where 0 is minimum and means no pain while 10 is maximum and means maximum pain which means worse outcome	24 hours postoperatively

Collaborators and Investigators

• Sponsor: Ain Shams University
• Investigators: Principal Investigator: Ahmed A. Khalifa, MD, Ain Shams University

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2024
• Primary Completion (Actual): July 1, 2024
• Study Completion (Actual): August 1, 2024

Study Registration Dates

• First Submitted: December 7, 2023
• First Submitted That Met QC Criteria: December 17, 2023
• First Posted (Actual): January 3, 2024

Study Record Updates

• Last Update Posted (Actual): January 21, 2026
• Last Update Submitted That Met QC Criteria: January 1, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Postoperative Pain; Nerve Block; Breast Neoplasms; Anesthesia, Conduction; Mastectomy, Modified Radical; Analgesia, Opioid
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Nervous System Diseases; Postoperative Complications; Pathologic Processes; Neoplasms by Site; Neoplasms; Neurobehavioral Manifestations; Skin Diseases; Breast Diseases; Perceptual Disorders; Pathological Conditions, Signs and Symptoms; Skin and Connective Tissue Diseases; Signs and Symptoms; Pain, Postoperative; Breast Neoplasms; Agnosia
• Other Study ID Numbers: FMASU MD311/2023

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data (IPD) will not be shared because of institutional policy and patient confidentiality concerns. Only summarized results will be made available in the published manuscript and upon reasonable request.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No