An interventional study of Erector Spinae Plane Block and Modified External Oblique Intercostal Plane Block in Postoperative Pain and Open Nephrectomy, sponsored by Namik Kemal University. Recruiting at 1 site in Turkey (Türkiye). Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-09-25.
Sponsored by Namik Kemal University · Not applicable, Interventional, and Treatment
This prospective, randomized, assessor-blinded clinical trial aims to compare the postoperative analgesic efficacy of ultrasound-guided Erector Spinae Plane Block (ESPB) and Modified External Oblique Intercostal Plane Block (EOIPB) in patients undergoing elective open nephrectomy under general anesthesia. Sixty adult patients will be randomized to receive either ESPB or EOIPB before surgical incision. All participants will receive standardized general anesthesia and postoperative multimodal analgesia. Postoperative pain scores, opioid consumption, rescue analgesic requirements, and postoperative nausea and vomiting will be assessed during the first 24 hours after surgery. The study aims to determine whether one fascial plane block technique provides superior postoperative pain control and recovery following open nephrectomy.
Open nephrectomy is associated with substantial postoperative pain that may impair recovery, delay mobilization, and increase opioid consumption. Regional anesthesia techniques have become important components of multimodal analgesia strategies aimed at improving postoperative outcomes while minimizing opioid-related adverse effects.
The erector spinae plane block (ESPB) and modified external oblique intercostal plane block (EOIPB) are ultrasound-guided fascial plane blocks that have demonstrated effectiveness in providing thoracoabdominal analgesia. However, evidence directly comparing these techniques in patients undergoing open nephrectomy remains limited.
This study is a prospective, randomized, controlled, assessor-blinded clinical trial conducted at a single tertiary academic center. Sixty patients aged 18 to 65 years with ASA physical status I-II who are scheduled for elective open nephrectomy will be enrolled and randomized in a 1:1 ratio to one of two study groups.
Participants assigned to the ESPB group will receive an ultrasound-guided erector spinae plane block with 30 mL of 0.25% bupivacaine after induction of general anesthesia and before surgical incision. Participants assigned to the EOIPB group will receive an ultrasound-guided modified external oblique intercostal plane block using the same volume and concentration of local anesthetic.
All patients will receive standardized general anesthesia, postoperative intravenous patient-controlled analgesia with tramadol, scheduled paracetamol, and rescue analgesics according to institutional protocols. Patients will be followed in the post-anesthesia care unit and at postoperative 2, 6, 12, and 24 hours.
The primary objective is to compare postoperative pain intensity between the two groups during the first 24 postoperative hours. Secondary objectives include comparison of opioid consumption, rescue analgesic requirements, postoperative nausea and vomiting, and perioperative hemodynamic parameters.
The results of this study may help identify the optimal regional analgesia technique for patients undergoing open nephrectomy and contribute to enhanced postoperative recovery.
5,640 studies on the registry are indexed under Pain, Postoperative; 1,230 are open to participants now.
This study's planned enrollment of 60 is below the median of 75 across 4,821 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →Namik Kemal University is the lead sponsor of 61 studies on the registry; 17 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive an ultrasound-guided erector spinae plane block with 30 mL of 0.25% bupivacaine after induction of general anesthesia and before surgical incision. Standardized general anesthesia and postoperative multimodal analgesia will be provided to all participants.
Procedure: Erector Spinae Plane Block
Participants will receive an ultrasound-guided modified external oblique intercostal plane block with 30 mL of 0.25% bupivacaine after induction of general anesthesia and before surgical incision. Standardized general anesthesia and postoperative multimodal analgesia will be provided to all participants.
Procedure: Modified External Oblique Intercostal Plane Block
Ultrasound-guided erector spinae plane block performed after induction of general anesthesia using 30 mL of 0.25% bupivacaine before surgical incision.
Ultrasound-guided modified external oblique intercostal plane block performed after induction of general anesthesia using 30 mL of 0.25% bupivacaine before surgical incision.
Pain intensity at rest
Postoperative pain intensity will be assessed at rest using the 11-point Numeric Rating Scale, ranging from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate greater pain intensity.
Time frame: 0, 2, 6, 12, and 24 hours after surgery
Pain intensity during movement
Postoperative pain intensity will be assessed during movement using the 11-point Numeric Rating Scale, ranging from 0 to 10, where 0 indicates no pain and 10 indicates the worst imaginable pain. Higher scores indicate greater pain intensity.
Time frame: 0, 2, 6, 12, and 24 hours after surgery
Total Opioid Consumption
Total postoperative tramadol consumption recorded from patient-controlled analgesia during the first 24 postoperative hours.
Time frame: 24 hours after surgery
Rescue Analgesic Requirement
Number of patients requiring rescue analgesia during the first 24 postoperative hours.
Time frame: 24 hours after surgery
Postoperative Nausea and Vomiting
Incidence of postoperative nausea and vomiting during the first 24 postoperative hours.
Time frame: 24 hours after surgery
Heart Rate
Intraoperative heart rate measured in beats per minute at predefined intraoperative time points.
Time frame: From induction of anesthesia until the end of surgery
Mean Arterial Pressure
Intraoperative mean arterial pressure measured in millimeters of mercury at predefined intraoperative time points.
Time frame: From induction of anesthesia until the end of surgery
Plan to share: No — De-identified individual participant data are not planned to be shared because no formal data-sharing infrastructure or approved data-sharing plan has been established for this study.
No publications or documents are linked to this record.
Started Aug 2026 (actual). Primary completion is estimated for Feb 2027, 6 months after the start.
Of 2,089 non-industry interventional studies with no phase under Pain, Postoperative, half reached primary completion within 11 months of starting (the median), counting those still running; a quarter within 6 and three quarters within 23. This study's planned 6 months is below that.
Counting every sponsor, half of 2,102 studies reached it within 11 months; a quarter within 6 and three quarters within 23.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Namik Kemal University