An interventional study of Neurostimulation and Ultrasound in Hemorrhoids, sponsored by GCS Ramsay Santé pour l'Enseignement et la Recherche. Not yet recruiting at 1 site in France. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-06-11.
Sponsored by GCS Ramsay Santé pour l'Enseignement et la Recherche · Not applicable, Interventional, and Treatment
In a population of patients undergoing hemorrhoidal surgery under general anesthesia and divided into two equal groups based on the method used for intraoperative pudendal nerve block and its branches in the ischioanal fossa:
Group 1: Pudendal block guided by neurostimulation Group 2: Pudendal block guided by ultrasound
The primary objective of this study is to compare the maximum immediate postoperative pain score between the two groups (pain reported by the patients in the recovery room on a simple numeric scale before morphine titration).
This is a multicenter, prospective, randomized, double-blind study conducted on two parallel groups of patients undergoing hemorrhoidal surgery (pudendal block guided by neurostimulation versus pudendal block guided by ultrasound).
Study Duration The total study duration per patient is 7 days. The recruitment period is set at 12 months.
Justification of the Experimental Protocol The aim of this study is to compare two methods of performing a pudendal block. Patient allocation to either strategy will be determined by randomization. Bilateral pudendal nerve block and its branches in the ischioanal fossa will be performed after induction of general anesthesia.
To maintain double blinding, postoperative data will be collected by a physician other than the anesthesiologist performing the block, and by nursing staff under their supervision. None of these personnel will be informed of the patient's group allocation.
238 studies on the registry are indexed under Hemorrhoids; 73 are open to participants now.
This study's planned enrollment of 202 is above the median of 100 across 183 interventional studies indexed under Hemorrhoids.
Browse Hemorrhoids studies →GCS Ramsay Santé pour l'Enseignement et la Recherche is the lead sponsor of 207 studies on the registry; 99 are open to participants now.
Counted across the registry records on this site, refreshed daily.
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.
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.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
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.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Neurostimulation involves using an electrical impulse to trigger a nerve signal and a specific motor response. A short-bevel, insulated 80 mm needle connected to a neurostimulator is used. The puncture point lies midway between the ischial tuberosity and the anus. Stimulation starts at 2.5 mA, 1 Hz, and the needle is advanced 4-5 cm until anal sphincter contraction occurs ("anal wink"). The needle is adjusted to maintain the response while reducing intensity to 0.5 mA. If lost, intensity is increased; if too intense at 0.3 mA, the needle is repositioned. After confirming no vascular puncture, 1 mL of Ropivacaine 3.5 mg/mL is injected to stop contraction, followed by slow injection of 15 mL total. The procedure is repeated on the other side. If no motor response occurs, a blind injection is performed after negative aspiration at 5 cm depth using the same landmarks.
Procedure: Neurostimulation
A 6 MHz convex probe is placed in the frontal plane along the line between the ischial tuberosity and the anal margin to visualize the bony prominence. The pudendal artery and nearby nerves are identified using color Doppler. A 22-gauge, 80 mm echogenic needle is inserted out-of-plane in front of the probe, targeting the lateral ischioanal fossa just medial to the pudendal artery, if visible. The probe is adjusted to center the artery. Block confirmation is based on ultrasound visualization of local anesthetic spreading into the fatty tissue medial to the pudendal artery. The procedure is repeated on the other side. If the artery is not visible, the injection is performed after negative aspiration on the medial aspect of the ischial tuberosity, along the line to the anus, at a depth of 4-5 cm.
Procedure: Ultrasound
Procedure guided by neurostimulation
Procedure guided by ultrasound
Postoperative Pain assessment in the Post-Anesthesia Care Unit (PACU)
The primary endpoint of the study is the maximum pain score in the Post-Anesthesia Care Unit (PACU) before morphine titration. Postoperative pain in the recovery room will be recorded by the nursing staff using a simple numeric scale from 0 to 10 after questioning the patient, following standard departmental procedures. The maximum pain score before morphine titration constitutes the primary evaluation criterion.
Time frame: Hour 2
Quantitative Opioid Consumption
Mean amount of morphine administered in each group
Time frame: Hour 2
Qualitative Opioid Consumption
Percentage of patients in each group with zero morphine use
Time frame: Hour 2
Postoperative recovery assessment
QOR-15 accurately assesses postoperative recovery across five key domains: pain, physical comfort, physical independence, psychological support, and emotional state. Each item is rated from 0 (poor) to 10 (excellent), with a total score ranging from 0 (no recovery) to 150 (full recovery).
Time frame: Day 1
Postoperative recovery assessment
QOR-15 accurately assesses postoperative recovery across five key domains: pain, physical comfort, physical independence, psychological support, and emotional state. Each item is rated from 0 (poor) to 10 (excellent), with a total score ranging from 0 (no recovery) to 150 (full recovery).
Time frame: Day 3
Postoperative recovery assessment
QOR-15 accurately assesses postoperative recovery across five key domains: pain, physical comfort, physical independence, psychological support, and emotional state. Each item is rated from 0 (poor) to 10 (excellent), with a total score ranging from 0 (no recovery) to 150 (full recovery).
Time frame: Day 7
Postoperative Pain assessment at rest
Postoperative pain will be measured by nursing staff during the patient's ambulatory stay, and the maximum score will be recorded in the Case Report Form (CRF). Pain will be self-reported by the patient using a simple numeric scale from 0 to 10.
Time frame: Day 1
Postoperative Pain assessment at rest
Postoperative pain will be measured by nursing staff during the patient's ambulatory stay, and the maximum score will be recorded in the Case Report Form (CRF). Pain will be self-reported by the patient using a simple numeric scale from 0 to 10.
Time frame: Day 3
Postoperative Pain assessment at rest
Postoperative pain will be measured by nursing staff during the patient's ambulatory stay, and the maximum score will be recorded in the Case Report Form (CRF). Pain will be self-reported by the patient using a simple numeric scale from 0 to 10.
Time frame: Day 7
Postoperative Pain assessment during walking
Postoperative pain will be measured by nursing staff during the patient's ambulatory stay, and the maximum score will be recorded in the Case Report Form (CRF). Pain will be self-reported by the patient using a simple numeric scale from 0 to 10.
Time frame: Day 1
Postoperative Pain assessment during walking
Postoperative pain will be measured by nursing staff during the patient's ambulatory stay, and the maximum score will be recorded in the Case Report Form (CRF). Pain will be self-reported by the patient using a simple numeric scale from 0 to 10.
Time frame: Day 3
Postoperative Pain assessment during walking
Postoperative pain will be measured by nursing staff during the patient's ambulatory stay, and the maximum score will be recorded in the Case Report Form (CRF). Pain will be self-reported by the patient using a simple numeric scale from 0 to 10.
Time frame: Day 7
Postoperative Pain assessment during First defecation
Postoperative pain will be measured by nursing staff during the patient's ambulatory stay, and the maximum score will be recorded in the Case Report Form (CRF). Pain will be self-reported by the patient using a simple numeric scale from 0 to 10.
Time frame: Day 7
Non-Opioid Postoperative Medication Use
Use of non-opioid analgesics and antiemetics during hospitalization. Use of analgesics as reported by the patients.
Time frame: Day 1
Pudendal block procedure duration
Duration of pudendal block procedure
Time frame: Hour 2
Sensory block duration
Duration of sensory block
Time frame: Day 7
Length of stay in the PACU
Length of stay in the PACU
Time frame: Day 1
Total hospital stay duration
Total hospital stay duration
Time frame: Day 1
Time to first defecation
Time to first defecation
Time frame: Day 7
Tolerance
Procedure tolerance will be assessed by recording all adverse events (serious or non-serious) with a potential causal link to analgesia
Time frame: Day 7
Start is estimated for Aug 2025; primary completion for Aug 2026, 12 months later.
Of 65 non-industry interventional studies with no phase under Hemorrhoids, half reached primary completion within 23 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 35. This study's planned 12 months is below that.
Counting every sponsor, half of 70 studies reached it within 23 months; a quarter within 10 and three quarters within 35.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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