Informations générales
  • Catégorie de maladie Recherche de base (anatomie/physiologie) , Autre (BASEC)
  • Study Phase N/A (ICTRP)
  • État du recrutement recrutement terminé (BASEC/ICTRP)
  • Lieu de l’étude
    Zurich
    (BASEC)
  • Responsable de l'étude Prof Dr. med Urs Eichenberger anaesthesiologie@balgrist.ch (BASEC)
  • Source(s) de données BASEC: Importé de 24.11.2025 ICTRP: Importé de 14.12.2025
  • Date de mise à jour 14.12.2025 02:00
HumRes65926 | SNCTP000006151 | BASEC2024-01431 | NCT06668116

Determination of an anesthetic concentration that can be used in the future as a so-called active placebo.

  • Catégorie de maladie Recherche de base (anatomie/physiologie) , Autre (BASEC)
  • Study Phase N/A (ICTRP)
  • État du recrutement recrutement terminé (BASEC/ICTRP)
  • Lieu de l’étude
    Zurich
    (BASEC)
  • Responsable de l'étude Prof Dr. med Urs Eichenberger anaesthesiologie@balgrist.ch (BASEC)
  • Source(s) de données BASEC: Importé de 24.11.2025 ICTRP: Importé de 14.12.2025
  • Date de mise à jour 14.12.2025 02:00

Résumé de l'étude

Local nerve anesthesia with local anesthetics is used in pain medicine for various purposes: diagnostic blocks for pain relief, prognostic blocks to assess the effectiveness of future treatments, and therapeutic blocks for long-term pain relief. However, there is limited scientific evidence for their effectiveness and safety, as comprehensive placebo-controlled studies are lacking. A barrier to researching nerve blocks in such studies is the difficulty in ensuring successful blinding of participants and examiners, as nerve blocks often cause numbness and motor impairments. This study aims to determine the correct dosage of a placebo anesthetic to enable future studies that can more accurately examine the effects of nerve blocks. * Placebo-controlled means that in a study, in addition to the actual anesthetic, a sham anesthetic (placebo) is also used.

(BASEC)

Intervention étudiée

The concentration of the anesthetic (Ropivacaine) is determined using an up-down model. The initial concentration is 0.1% of the anesthetic, which is very likely to lead to a nerve block after 60 minutes. Depending on how the first subject reacts, the next subject will receive a higher or lower dose. The dose is increased (+0.025%) if: - the pain relief is less than 50%, OR - the pain relief is between 50% and 75% and there is no sensory or strength impairment. The dose is reduced (-0.025%) if: - the pain relief is between 50% and 75% and there is a sensory or strength impairment, OR - the pain relief is more than 75%. This method helps to reduce the number of people needed to find out how much Ropivacaine is needed to achieve pain relief without the affected individuals experiencing noticeable sensory or strength impairment. For safety reasons, the highest concentration of Ropivacaine to be used is limited to 0.5%. This corresponds to the concentration used in daily practice for nerve blocks in regional anesthesia to achieve complete anesthesia during surgical procedures.

(BASEC)

Maladie en cours d'investigation

Investigation of the dose-dependent effects of Ropivacaine, an anesthetic.

(BASEC)

Critères de participation
- Individuals in good health - Age: from ≥ 18 years to < 65 years - Written consent after information (BASEC)

Critères d'exclusion
- Known intolerance/hypersensitivity to the anesthetic being studied (Ropivacaine) - Chronic or acute pain - Use of pain-relieving medications (BASEC)

Lieu de l’étude

Zurich

(BASEC)

Switzerland (ICTRP)

Sponsor

Universitätsklinik Balgrist

(BASEC)

Contact pour plus d'informations sur l'étude

Personne de contact en Suisse

Prof Dr. med Urs Eichenberger

+41 44 386 38 32

anaesthesiologie@balgrist.ch

Anästhesie Universitätsklinik Balgrist

(BASEC)

Informations générales

Deputy Head of Anesthesiology,

0041 44 386 38 32

hagen.bomberg@balgrist.ch

(ICTRP)

Informations générales

Deputy Head of Anesthesiology

0041 44 386 38 32

hagen.bomberg@balgrist.ch

(ICTRP)

Informations générales

Deputy Head of Anesthesiology

(ICTRP)

Informations scientifiques

Deputy Head of Anesthesiology,

0041 44 386 38 32

hagen.bomberg@balgrist.ch

(ICTRP)

Nom du comité d'éthique approbateur (pour les études multicentriques, uniquement le comité principal)

Commission cantonale de Zurich

(BASEC)

Date d'approbation du comité d'éthique

18.10.2024

(BASEC)


Identifiant de l'essai ICTRP
NCT06668116 (ICTRP)

Titre officiel (approuvé par le comité d'éthique)
The impact of local anesthetic dilution on the possibility of blinding studies involving peripheral nerve blocks. A randomized, prospective, monocentric study on volunteers (BASEC)

Titre académique
The Impact of Local Anesthetic Dilution on the Possibility of Blinding Studies Involving Peripheral Nerve Blocks. A Randomized, Prospective, Monocentric Study on Volunteers (ICTRP)

Titre public
The Impact of Local Anesthetic Dilution on Possible Blinding for Nerve Blocks (ICTRP)

Maladie en cours d'investigation
Healthy (ICTRP)

Intervention étudiée
Drug: Ropivacaine 0,1%Other: NaCl (placebo) (ICTRP)

Type d'essai
Interventional (ICTRP)

Plan de l'étude
Allocation: Randomized. Intervention model: Crossover Assignment. Primary purpose: Other. Masking: Double (Participant, Investigator). (ICTRP)

Critères d'inclusion/exclusion
Inclusion Criteria:

- ASA I - II, both sexes

- = 18 years old

- < 65 years old

- Written informed consent as documented by signature

Exclusion Criteria:

- Known allergy or hypersensitivity to a ropivacaine, amide local anesthetics or
ultrasound gel

- Any history of chronic or acute pain at the moment of enrollment into the study

- Treatment with any substance having a relation to pain or pain modulation
(antidepressants, opioids, benzodiazepines, anticonvulsants)

- Intake of any analgesic 48 hours prior to the conduction of any of the study stages

- Severe coagulopathy

- History of cardiovascular disease

- History of alcohol abuse or the intake of psychotropic drugs

- Pregnancy, ruled out by history

- Infection at the injection site or a systemic infection

- Fever of unknown origin

- Motor or sensory abnormalities in the arm

- Previous enrollment into the current study (ICTRP)

non disponible

Critères d'évaluation principaux et secondaires
Heat pain sensitivity;Self-report of sensory block;Self-report of motor block (ICTRP)

Evaluation of the C-fiber block;Evaluation of the A-delta fiber block;Evaluation of the A-beta fiber block;Evaluation of the A-alpha fiber block (motor block);Offset analgesia (ICTRP)

Date d'enregistrement
30.10.2024 (ICTRP)

Inclusion du premier participant
non disponible

Sponsors secondaires
non disponible

Contacts supplémentaires
Hagen Bomberg, Medical Doctor;Hagen Bomberg, Medical Doctor, hagen.bomberg@balgrist.ch, 0041 44 386 38 32, Deputy Head of Anesthesiology, (ICTRP)

ID secondaires
2024-01431 (ICTRP)

Résultats-Données individuelles des participants
non disponible

Informations complémentaires sur l'essai
https://clinicaltrials.gov/study/NCT06668116 (ICTRP)

Résultats de l'essai

Résumé des résultats

non disponible

Lien vers les résultats dans le registre primaire

non disponible