Pain, Acute
Conditions
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.
Interventions
DEVICETENS eco 2 Transauricular vagal nerve stimulation
Auricular electrical stimulation will be applied bilaterally using Transcutaneous Electrical Nerve Stimulation device TENS eco 2 (Schwa-Medico, Pierenkemper GmbH, Ehringshausen, Germany). tVNS will be applied bilaterally using electrical square impulses delivered in blocks of 9 impulses with a frequency of 100 Hz and a pulse width of 200 μs emitted twice per second resulting in mixed frequency pattern of 100 Hz/2 Hz with the current intensity, that will be individually adjusted for each ear separately until the maximal tVNS intensity, which is not uncomfortable or painful, will be achieved.
DEVICESham TENS eco 2
Sham
Sponsors
University Medicine Greifswald
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Real tVNS will be applied using pre-defined characteristics of tVNS device to cymba conchae of the auricle, sham procedure will be the same, however applied to tubule of the auricle
Intervention model description
Two periods (real and sham tVNS) randomized crossover investigation in healthy volunteers
Eligibility
Sex/Gender
ALL
Age
19 Years to 40 Years
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 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
| Measure | Time frame | Description |
|---|---|---|
| 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 |
Countries
Germany
Contacts
Primary ContactTaras Usichenko, MD, PhD
Outcome results
None listed