Rhomboid Intercostal Sub-serratus Plane Block Versus External Oblique Intercostal Block in Open Nephrectomy

Ultrasound Guided Rhomboid Intercostal Sub-serratus Plane Block Versus External Oblique Intercostal Block in Open Nephrectomy: Randomized Controlled Study

This study aims to compare time of first request of analgesia among patients undergoing rhomboid intercostal sub-serratus plane block versus external oblique intercostal block for perioperative pain management in open nephrectomy.

Study Overview

• Status: Recruiting
• Conditions: Open Nephrectomy; External Oblique Intercostal Block; Rhomboid Intercostal Sub-serratus Plane Block
• Intervention / Treatment: Other: Rhomboid intercostal subserratus plane block; Other: External oblique intercostal block; Drug: Intravenous morphine

Detailed Description

Open nephrectomy is a common surgery usually performed for malignant and non-malignant renal pathologies. Open nephrectomy incision is associated with a high incidence of intense immediate postoperative pain and chronic pain the months following surgery.

The rhomboid intercostal block has previously been used for pain management in thoracic wall surgery.

Subserratus plane block in the treatment of post-abdominal surgical pain and the combination of the two blocks was subsequently renamed the "RISS block". The nerves targeted by the RISS block include the lateral cutaneous branches of the ventral branches of the thoracic intercostal nerves, located between the rhomboid muscle and the intercostal muscles, and deep into the scapula serratus anterior muscle. RISS block provides analgesia from T4 to T9 thoracic dermatomes and has been used in postoperative pain management for thoracic surgeries and upper abdominal surgeries.

• Study Type: Interventional
• Enrollment (Estimated): 90
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Amr R Seif, MD; Phone Number: 00201066588692; Email: amroseifo40404@gmail.com

Study Locations

• Egypt
  • Cairo, Egypt, 12613
    • Recruiting
    • Cairo University
    • Contact: Amr R Seif, MD; Phone Number: 00201066588692; Email: amroseifo40404@gmail.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Both sexes.
• American Society of Anesthesiologists (ASA) physical status II, III.
• Body mass index (BMI): > 20 kg/ m2 and < 35 kg/ m2.
• Patients undergoing open nephrectomy.

Exclusion Criteria:

• Patient refusal.
• BMI <20 kg/m2 and >35 kg/m2
• Known sensitivity or contraindication to drug used in the study (local anesthetics, opioids).
• History of psychiatric and cognitive disorders or chronic pain.
• Contraindication to regional anesthesia e.g pre- existing peripheral neuropathies.
• Severe respiratory or cardiac disorders.
• Advanced liver or kidney disease.
• Pregnancy.
• Physical status ASA IV.
• Coagulopathy with INR ≥ 1.6: hereditary (e.g. hemophilia, fibrinogen abnormalities & deficiency of factor II) - acquired (e.g. impaired liver functions with prothrombin concentration less than 60 %, vitamin K deficiency & therapeutic anticoagulants drugs).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group (A); Patients will receive the rhomboid intercostal subserratus plane block.	Other: Rhomboid intercostal subserratus plane block; Patients will receive the rhomboid intercostal subserratus plane block.
Experimental: Group (B); Patients will receive the external oblique intercostal block.	Other: External oblique intercostal block; Patients will receive the external oblique intercostal block.
Active Comparator: Control group; Patients will not receive any interventions (IV morphine 0.1mg/kg after induction of general anesthesia).	Drug: Intravenous morphine; Patients will not receive any interventions (Intravenous morphine 0.1mg/kg after induction of general anesthesia).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time of first request of analgesia	Time of first request of analgesia will be recorded from the end of surgery till first dose of morphine administrated.	24 hours postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Heart rate	Heart rate will be noted immediately on arrival and at 0, 4, 8, 12, 18 and 24 h postoperatively.	24 hours postoperatively
Mean arterial blood pressure	Mean arterial blood pressure will be noted immediately on arrival and at 0, 4, 8, 12, 18 and 24 h postoperatively.	24 hours postoperatively
Total amount of fentanyl	Fentanyl 0.5 μg / kg will be given in case of heart rate or mean arterial blood pressure ≥ 20% of the baseline	24 hours postoperatively
Total morphine consumption	Intravenous morphine (3 mg) will be provided as rescue of analgesia. The total amount of morphine given in 24 h will be recorded.	24 hours postoperatively
Degree of pain	Each patient will be instructed about postoperative pain assessment with the numeric rating scale (NRS) score. NRS (0 represents "no pain" while 10 represents "the worst pain imaginable"). NRS will be recorded at 30 minutes, 2,4, 8, 12, 16, 24 hours postoperatively.	24 hours postoperatively
Incidence of block related complications	Incidence of block related complications such as local anesthetic toxicity, hematoma formation, and pneumothorax will be recorded.	24 hours postoperatively

Collaborators and Investigators

• Sponsor: Cairo University

Study record dates

Study Major Dates

• Study Start (Actual): May 2, 2026
• Primary Completion (Estimated): December 30, 2026
• Study Completion (Estimated): December 30, 2026

Study Registration Dates

• First Submitted: June 7, 2026
• First Submitted That Met QC Criteria: June 7, 2026
• First Posted (Actual): June 11, 2026

Study Record Updates

• Last Update Posted (Actual): June 11, 2026
• Last Update Submitted That Met QC Criteria: June 7, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: AP2604-501-160-209

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The data will be available upon a reasonable request from the corresponding author after the end of study for one year.
• IPD Sharing Time Frame: After the end of study for one year.
• IPD Sharing Access Criteria: The data will be available upon a reasonable request from the corresponding author.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No