Comparison of Intrathecal Morphine and Rectus Sheath Block for Postoperative Pain Management After Lower Abdominal Surgery With Midline Incision

NCT07489872 | Active Not Recruiting

• 1 other identifier: 09.2025.174
• Study Type: interventional
• Target: 66
• Locations: 1 country
• Sites: 2

Brief Summary

This study aims to evaluate the efficacy of intrathecal morphine and rectus sheath block compared with standard postoperative analgesia for pain management in patients undergoing lower abdominal surgery with a midline incision. Effective postoperative analgesia is essential to enhance recovery, reduce opioid consumption, and improve overall patient comfort. In this prospective randomized controlled trial, eligible patients scheduled for lower abdominal surgery through a midline incision will be randomly assigned to one of three groups: intrathecal morphine, rectus sheath block, or control (standard postoperative analgesia without regional intervention). Postoperative outcomes will include pain scores, quality of recovery (QoR) scores, functional recovery parameters, patient satisfaction, incidence of postoperative nausea and vomiting, and rescue analgesic requirements. The findings of this study may provide evidence on the comparative effectiveness of these analgesic strategies and contribute to the development of optimized multimodal pain management protocols in lower abdominal surgery.

Conditions

Postoperative Analgesia; Pain Management

Keywords

intrathecal morphine; rectus sheath block; lower abdominal surgery; postoperative analgesia

Outcome Measures

Primary Outcomes (1)

• Opioid Consumption

  The total amount of intravenous tramadol administered during the first 24 hours after surgery will be recorded to evaluate postoperative analgesic requirements.

  24 hours postoperatively

Secondary Outcomes (4)

• Change in QoR-15 score

  preoperative baseline and 24 hours postoperatively

• NRS Score

  24 hours postoperatively

• Functional recovery

  24 hours postoperatively

• Rescue Analgesic Consumption

  24 hours postoperatively

Study Arms (2)

Intrathecal Morphine

ACTIVE COMPARATOR

Patients in this group will receive intrathecal morphine administered prior to general anesthesia as part of their perioperative analgesic regimen for postoperative pain control following lower abdominal surgery with a midline incision. Standard postoperative care will also be provided.

Procedure: Intrathecal Morphine

Bilateral Rectus Sheath Block

ACTIVE COMPARATOR

Patients in this group will receive a bilateral rectus sheath block administered after general anesthesia but prior to surgical incision, in addition to standard postoperative analgesia for pain management following lower abdominal surgery via midline incision.

Procedure: Rectus Sheath Block

Interventions

Intrathecal Morphine PROCEDURE

Patients in this group will receive 200 mcg of intrathecal morphine administered at the L3-L4 interspace prior to general anesthesia as part of their perioperative analgesic regimen for postoperative pain control following lower abdominal surgery with a midline incision. As part of standard perioperative care, all patients will receive 8 mg dexamethasone and 1.5 mg/kg intravenous tramadol. Postoperatively, all patients will have intravenous tramadol PCA (10 mg/kg). Rescue analgesia with 3 mg intravenous morphine will be administered if the numeric rating scale (NRS) pain score is 4 or higher.

Intrathecal Morphine

Rectus Sheath Block PROCEDURE

Patients in this group will receive a bilateral rectus sheath block after induction of general anesthesia but prior to surgical incision, with 20 ml solution (10 ml of 0.25% bupivacaine and 10 ml of normal saline) administered to each side, in addition to standard perioperative analgesia. As part of standard care, all patients will receive 8 mg dexamethasone and 1.5 mg/kg intravenous tramadol. Postoperatively, all patients will have intravenous tramadol PCA (10 mg/kg). Rescue analgesia with 3 mg intravenous morphine will be administered if the numeric rating scale (NRS) pain score is 4 or higher.

Bilateral Rectus Sheath Block

Eligibility Criteria

• Age: 18 Years - 90 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients over 18 years old
• Patients undergoing lower abdominal surgery via midline incision.

You may not qualify if:

• Patients with solid organ dysfunction
• Patients who receive opioid or corticosteroid medication prior to surgery
• Patients with bleeding diathesis
• Patients with psychiatric disorders
• Patients who can not be contacted after surgery

Sponsors & Collaborators

• Marmara University: lead

Study Sites (2)

Marmara University School of Medicine, Istanbul

Istanbul, Turkey (Türkiye)

Location

Marmara University School of Medicine

Istanbul, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Agnosia

Condition Hierarchy (Ancestors)

Perceptual Disorders; Neurobehavioral Manifestations; Neurologic Manifestations; Nervous System Diseases; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 18, 2026
• First Posted: March 24, 2026
• Study Start: February 24, 2025
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): July 30, 2026
• Last Updated: March 30, 2026

Record last verified: 2026-03

Data Sharing

• IPD Sharing: Will not share

Locations

TU (2)