Antinociceptive Effect of Transauricular Electrical Vagal Nerve Stimulation

Not Applicable

• Conditions: Pain, Acute
• Interventions: Device: TENS eco 2 Transauricular vagal nerve stimulation; Device: Sham TENS eco 2

• Registration Number: NCT04448990
• Lead Sponsor: University Medicine Greifswald

Brief Summary

This investigation is going to study whether electrical tVNS applied at the cymba of auricular conchae reduces central sensitization of experimentally induced pain in comparison with electrical sham stimulation applied at the earlobes and whether the hypoalgesic effects of tVNS disappear after pharmacological block of muscarinic receptors. Also, this investigation will examine whether tVNS is associated with activation in brain areas, involved in processing of thermal pain stimuli and emotional and vegetative modulation of thermal pain in subjects who will respond with antinociceptive reaction to tVNS.

Detailed Description

Not available

Study Timeline

• Status Verified: 2020-06
• Study First Submitted: 2020-06-23
• Study First Submitted QC: 2020-06-25
• Last Update Submitted: 2020-06-25
• Study First Posted: 2020-06-26
• Last Update Posted: 2020-06-26
• Study Start: 2021-05
• Primary Completion: 2023-04
• Study Completion: 2023-08

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 66

Inclusion Criteria

• healthy volunteers aged 18-45 years old, who have given informed consent
• at least two days free from consume of recreational drugs
• no local infection at the site of tVNS and pain stimulation

Exclusion Criteria

• psychiatric disorders
• abnormal skin conditions (infection, scars, psoriasis, eczema) at the site of tVNS
• contra-indications for MRI (e.g. claustrophobia, pregnancy, tattoos, metallic implants)
• history of coronary heart disease, cardiac arrhythmia, glaucoma, allergy to sulphates

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
tVNS	TENS eco 2 Transauricular vagal nerve stimulation	Stimulation will be applied using TENS device eco 2 (Schwa-Medico, Pierenkemper GmbH, Ehringshausen, Germany) bilaterally at the cymba conchae of the auricles for 20 minutes. Current intensity (1-max. 10 mA) will be individually adjusted for each ear separately until the maximal tVNS intensity, which is not uncomfortable or painful, will be achieved.
Sham	Sham TENS eco 2	Same stimulation will be applied using TENS device eco 2 (Schwa-Medico, Pierenkemper GmbH, Ehringshausen, Germany) to bilaterally to the earlobes for 20 minutes. Current intensity (1-max. 10 mA) will be individually adjusted for each ear separately until the maximal tVNS intensity, which is not uncomfortable or painful, will be achieved.

Primary Outcome Measures

Name	Time	Method
Unpleasantness of pain	Continuously 5 minutes during the experimental heat pain stimulation	perceived unpleasantness of pain, which participants will rate continuously during the repetitive heat stimulation using a computerized visual analogue scale (CoVAS, Medoc Advanced Medical Systems, Ramat Yishai, Israel) ranging from 0 (= not unpleasant at all) to 100 (= intolerable pain).

Secondary Outcome Measures

Name	Time	Method
Heart rate	Continuously 5 minutes during the experimental heat pain stimulation	Heart rate (bpm)
Blood pressure	4 times during 5 minutes of the experimental heat pain stimulation	Systolic and diastolic blood pressure

Trial Locations

Locations (1)

University Medicine of Greifswald; 🇩🇪 Greifswald, Germany