The Effectiveness of External Oblique Intercostal Plane Block

The Effectiveness of External Oblique Intercostal Plane Block Application in the Treatment of Acute Pain After Nephrectomy

The aims of the study are as follows:To examine postoperative opioid consumption.To assess the effectiveness of external oblique intercostal plane block in managing postoperative pain in nephrectomy patients.To evaluate pain at postoperative hours 0, 2, 4, 6, 12, and 24 using the Numerical Rating Scale (NRS).To assess pain increase with movement and effort at postoperative hours 0, 2, 4, 6, 12, and 24 using NRS.

Study Overview

• Status: Completed
• Conditions: Pain, Postoperative
• Intervention / Treatment: Other: External oblique intercostal plane block; Other: intavenous tramadol

Detailed Description

The Effectiveness of External Oblique Intercostal Plane Block in the Management of Acute Pain Following NephrectomyNephrectomy is a commonly performed surgical procedure in urology due to benign or malignant reasons. Depending on the underlying pathology and the patient, the surgical procedure can vary in scale, including simple nephrectomy, partial nephrectomy, and radical nephrectomy, and may be performed either openly or laparoscopically. Postoperative pain can prolong the patient's hospital stay and impair comfort. Due to pain, patients may develop atelectasis and hypertension after surgery, leading to an increased need for narcotic analgesia. The increased demand for narcotic analgesics according to patients' age and characteristics can affect renal functions and may not improve patient comfort due to nausea and vomiting. Regional anesthesia of the torso and abdominal wall has generally focused on epidural analgesia. However, the increased use of minimally invasive laparoscopic techniques, the significance of postoperative anticoagulation regimens, and early ambulation have led to changes in analgesia selection. Although transversus abdominis plane blocks and rectus sheath blocks are frequently applied, their inability to adequately manage abdominal pain alone, along with the challenges posed in obese patients, has led to a recent shift towards the external oblique intercostal plane block.The application of the EOIP block involves the patient being in a supine position, with either the clavicle or mid-axillary line palpated to locate the 6th rib. An ultrasound probe is placed 1-2 cm lateral to the midclavicular line over the 6th rib. Under aseptic conditions, a 22-gauge 25-50 mm block needle is advanced to the 6th rib using the in-plane technique. Two ml of saline is injected for hydrodissection to ensure accurate placement. Avoiding subperiosteal injection, hydrodissection is performed between the external oblique muscle and the 6th rib. Subsequently, 20-30 ml of 0.25% bupivacaine is injected into this area. The block is then repeated on the other side.

In our clinic, a multimodal analgesia approach is preferred for patients undergoing nephrectomy. Plan blocks (administered to every suitable and consenting patient) are used in conjunction with intravenous analgesic agents. Blocks are routinely applied to patients undergoing nephrectomy, who are monitored in the postoperative intensive care unit. Our study will include suitable patients who have undergone nephrectomy and received this block. The anesthesiologist managing anesthesia will be different from the anesthetist monitoring pain. Our study is entirely observational, and no randomization will be conducted. There will be no intervention in either analgesia or anesthesia management. Patients who consent to participate will be included in the study in the recovery room after the block is administered.

The aims of the study are as follows:To examine postoperative opioid consumption.To assess the effectiveness of external oblique intercostal plane block in managing postoperative pain in nephrectomy patients.To evaluate pain at postoperative hours 0, 2, 4, 6, 12, and 24 using the Numerical Rating Scale (NRS).To assess pain increase with movement and effort at postoperative hours 0, 2, 4, 6, 12, and 24 using NRS.

• Study Type: Interventional
• Enrollment (Actual): 60
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey
  • Ankara, Turkey
    • Gizem Avcı

Participation Criteria

Eligibility Criteria

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

Study Population

Patients who have undergone nephrectomy surgery

Description

Inclusion Criteria:

• Patients who have undergone nephrectomy surgery.
• Aged 18-80 years
• ASA (American Society of Anesthesiologists) I-II-III risk group that underwent nephrectomy.

Exclusion Criteria:

• Patients under 18 or over 80 years of age
• Patients with a history of bleeding diathesis
• Patients with infections at the block site

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: External Oblique Intercostal Plane Block group; The External Oblique Intercostal Plane Block was administered bilaterally with local anesthetic mixture of 20 ml volume (10 ml bupivacaine 0.5%, 5 ml lidocaine 2% and 5 ml isotonic saline) after completion of surgery.	Other: External oblique intercostal plane block; The external oblique intercostal plane block is applied to the patients at the end of the surgery.; Other: intavenous tramadol; Intravenous tramadol will be administered with patient-controlled analgesia
Placebo Comparator: Control group; At the end of the surgery, an isotonic solution was administered to the control group patients by inserting a needle through the entry site compatible with the external oblique intercostal block.	Other: intavenous tramadol; Intravenous tramadol will be administered with patient-controlled analgesia

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total opioid consumption	All patients will receive tramadol with a patient-controlled analgesia during the postoperative period	24 hours postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Numeric rating scale (NRS)	NRS range will from 0- 10 with 0 being no pain and 10 the worst pain possible.	0 hours postoperatively
Numeric rating scale (NRS)	NRS range will from 0- 10 with 0 being no pain and 10 the worst pain possible.	2 hours postoperatively
Numeric rating scale (NRS)	NRS range will from 0- 10 with 0 being no pain and 10 the worst pain possible.	4 hours postoperatively
Numeric rating scale (NRS)	NRS range will from 0- 10 with 0 being no pain and 10 the worst pain possible.	6 hours postoperatively
Numeric rating scale (NRS)	NRS range will from 0- 10 with 0 being no pain and 10 the worst pain possible.	12 hours postoperatively
Numeric rating scale (NRS)	NRS range will from 0- 10 with 0 being no pain and 10 the worst pain possible.	24 hours postoperatively

Collaborators and Investigators

• Sponsor: Ankara Etlik City Hospital
• Investigators: Principal Investigator: Gizem Avci, Ankara Etlik City Hospital

Publications and helpful links

General Publications

• White L, Ji A. External oblique intercostal plane block for upper abdominal surgery: use in obese patients. Br J Anaesth. 2022 May;128(5):e295-e297. doi: 10.1016/j.bja.2022.02.011. Epub 2022 Mar 3. No abstract available.
• Elsharkawy H, Kolli S, Soliman LM, Seif J, Drake RL, Mariano ER, El-Boghdadly K. The External Oblique Intercostal Block: Anatomic Evaluation and Case Series. Pain Med. 2021 Nov 26;22(11):2436-2442. doi: 10.1093/pm/pnab296.

Study record dates

Study Major Dates

• Study Start (Actual): April 2, 2025
• Primary Completion (Actual): May 15, 2025
• Study Completion (Actual): May 30, 2025

Study Registration Dates

• First Submitted: October 10, 2024
• First Submitted That Met QC Criteria: October 10, 2024
• First Posted (Actual): October 15, 2024

Study Record Updates

• Last Update Posted (Actual): June 29, 2025
• Last Update Submitted That Met QC Criteria: June 25, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Keywords: Nephrectomy; Postoperative pain; External Oblique Intercostal Plane Block
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Postoperative Complications; Pathologic Processes; Pain, Postoperative; Physiological Effects of Drugs; Peripheral Nervous System Agents; Central Nervous System Depressants; Sensory System Agents; Analgesics; Analgesics, Opioid; Narcotics; Tramadol
• Other Study ID Numbers: Gizem001

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