Pain Acute, Pain Perception
Conditions
Keywords
pain perception, tDCS, Hypnosis, cortical activity
Brief summary
Pain is a public health condition, which causes great functional disability. Its consequences pervade the personal and social life of the patient, leading to significant changes in their interpersonal relationships, including work, family and social spheres, reducing the ability to perform daily activities. Conventional treatment modalities have been show a very poor therapeutic response, in that most individuals end up becoming polymedicated patients and refractory to treatment. Among non-pharmacological techniques with promising analgesic effects it includes both the hypnotic analgesia and the transcranial stimulation of direct current (tDCS).
Detailed description
Introduction: Pain is a public health condition, which causes great functional disability. Its consequences pervade the personal and social life of the patient, leading to significant changes in their interpersonal relationships, including work, family and social spheres, reducing the ability to perform daily activities. Conventional treatment modalities have been show a very poor therapeutic response, in that most individuals end up becoming polymedicated patients and refractory to treatment. Among non-pharmacological techniques with promising analgesic effects it includes both the hypnotic analgesia and the transcranial stimulation of direct current (tDCS). Objective: To evaluate the synergistic effect of hypnotic analgesia associated with tDCS under metabolites parameters and pain levels in healthy individuals before a nociceptive stimulation pattern. Methods: it will be performed a blinded crossover sham controlled randomized clinical trial. It will be included 32 woman healthy subjects, Susceptible to the hypnosis technique according to the Scale of Hypnotic Susceptibility (WSGC) Scale of Hypnotic Scale score. aged 18 to 65. They will be allocated in one of the following groups: active tDCS + hypnotic analgesia, sham tDCS + hypnotic analgesia, hypnotic analgesia and tDCS . After a 7 days interval, the groups will be crossed in order to receive the opposite intervention of the first week. The primary endpoints will be the electrophysiological brain parameters, such as changes in the Theta, Alpha and Gamma waves, as measured by EEG. The secondary endpoints will be the level of pain, measured against nociceptive induced by the cold test and stimuli standardized pressure through algometry pressure and power down system modulatory pain, pain using the subject test - CPM - task. The intra and inter-group comparisons will be made by means of two-way ANOVA followed by Bonferroni. A p significance level of \<0.05 was established. Expected results: This study hypothesizes that a synergistic effect of analgesic techniques in pain levels in healthy subjects compared to isolated character.
Interventions
BEHAVIORALHypnotic analgesia
Subjects will receive hypnotic analgesia during 20 minutes
DEVICEa-tDCS
Subjects will receive transcranial direct stimulation over bilateral DLPFC left/anode right/cathodal, 2mA, 20 minutes
OTHERHypnotic analgesia + a-tDCS
Subjects will receive hypnotic analgesia associated to transcranial direct stimulation over bilateral DLPFC left/anode right/cathodal, 2mA, 20 minutes
DEVICEs-tDCS
Subjects will receive sham transcranial direct stimulation over bilateral DLPFC left/anode right/cathodal, 0mA, 20 minutes
Sponsors
Hospital de Clinicas de Porto Alegre
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Subjects are blinded to wether group they will be allocated Assessor will be blinded and the investigator not involved in subjects assessment will perform the hypnosis.
Intervention model description
1. Hypnotic analgesia + a-tDCS 2. Hypnotic analgesia + s-tDCS 3. Hypnotic analgesia 4. a-tDCS
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy * Female * 11 years of schooling * 12 cut-off at Waterloo-Stanford Group C (WSGC)
Exclusion criteria
* hearing loss subjects * formal contraindication to tDCS (pregnancy, deep brain device, epilepsy, seizure)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Alpha waves | 60 minutes | Variations in the alpha waves power from post to pre-intervention using electroencephalography during a cold pressor test |
| Change in Theta waves | 60 minutes | Variations in the theta waves power from post to pre-intervention using electroencephalography during a cold pressor test |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in beta waves | 60 minutes | Variations in the beta waves power from post to pre-intervention using electroencephalography during a cold pressor test |
| Change in gamma waves | 60 minutes | Variations in the gamma waves power from post to pre-intervention using electroencephalography during a cold pressor test |
| Change in delta waves | 60 minutes | Variations in the delta waves power from post to pre-intervention using electroencephalography during a cold pressor test |
| Change in Heat thermal threshold | 60 minutes | The measure will be assessed by Quantitative Sensorial Test - QST, in which a thermode delivers a heat stimulus of increasing magnitude. Heat thermal threshold (HTT) is the averaged temperature for 3 stimuli where participant indicates the first heat sensation. |
| Change in Heat pain threshold | 60 minutes | The measure will be assessed by Quantitative Sensorial Test - QST, in which a thermode delivers a heat stimulus of increasing magnitude. Heat pain threshold (HPT) is the averaged temperature for 3 stimuli where participant indicates the first heat pain sensation. |
| Change in Heat pain tolerance | 60 minutes | The measure will be assessed by Quantitative Sensorial Test - QST, in which a thermode delivers a heat stimulus of increasing magnitude. Heat pain tolerance (HPTo) is the temperature for the stimulus where participant indicates the maximum pain tolerance. |
| Change in Numeric pain scale during CPM task | 60 minutes | The measure will be assessed by the conditioned pain modulation (CPM) task in which an ice cold water (0 a 1 degrees Celsius) is the conditioning stimulus presented to the left hand and a moderate heat pain stimulus from the QST to the contralateral hand. The measure consists of the response using a numeric pain scale (0 - 10) for the heat pain stimulus during the CPM task. |
| Change in Cold Pressor Test 0 to 1 degree Celsius - time | 60 minutes | Participant puts his right hand in an ice cold water (0 a 1 degrees Celsius). Measure consists of the time (in seconds) the participant keeps his hand in the water the maximum he could tolerance. |
| Change in Cold Pressor Test 10 degree Celsius - time | 60 minutes | Participant puts his right hand in an ice cold water (10 degrees Celsius). Measure consists of the time (in seconds) the participant keeps his hand in the water the maximum he could tolerate. |
| Change in Cold Pressor Test 10 degree Celsius - pain | 60 minutes | Participant puts his right hand in an ice cold water (10 degrees Celsius). Measure consists of the response to a numeric pain scale (0 to 10) to the pain sensation when the participant withdraw his hand from the water. |
Countries
Brazil
Outcome results
None listed