Evaluation of the Potentiating Effect of tDCS on Opioid Analgesia of Pain Threshold in Humans
- Conditions
- Acute Pain
- Interventions
- Registration Number
- NCT02432677
- Lead Sponsor
- Hospital de Clinicas de Porto Alegre
- Brief Summary
The purpose of this study is to evaluate the potential additive effect of tDCS compared to placebo-sham in opioid analgesia on pain thresholds in nociceptive experimental model in healthy volunteers .
- Detailed Description
Pain is a prevalent symptom in medicine and the role of various opioids is valuable in the treatment of moderate to severe pain. Several technologies of brain stimulation , including transcranial direct current stimulation ( tDCS) are emerging as therapeutic options for many pain conditions. The effect of tDCS was demonstrated in sensory perception , decreasing the threshold for acute pain in healthy volunteers and in various chronic pain conditions . There is evidence about the use of tDCS with the participation through many mechanisms in cortical modulation , including the regulation of neurotransmitters, including opioids. In the context of neurostimulation, opioidergic system and cortical pain modulation, emerge the hypothesis of a possible potentiating effect of tDCS on clinical application of opioid analgesia.
Recruitment & Eligibility
- Status
- UNKNOWN
- Sex
- Male
- Target Recruitment
- 48
- Male
- Healthy
- Without medication
- Sign the informed consent
- Patients who did not understand the Portuguese
- Acute or chronic pain conditions
- Medical or psychiatric disorders
- History of sleep disorders (apnea, hypersomnia, somnambulism...)
- History of alcohol or substance abuse
- Neurological disorder
- Use of anti-inflammatory drugs, steroids and non-steroids, opioid and non-opioid analgesics, psychiatric medications, anticonvulsants, alpha and beta blockers
- Traumatic brain injury
- Neurosurgery
- Metallic implant in the brain
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Placebo + Active tDCS Active tDCS * tDCS session: the procedure will initiate by placing an anode electrode on the primary motor cortex (contralateral to the dominant cortex) and the cathode electrode on the contralateral supra-orbital region. The current employed is 2mA of transcranial direct-current stimulation administered for 20 minutes. * Placebo: Saline infusion - Infusion 10min before the tDCS session, during the tDCS session and after the tDCS session, until the end of pain tests. Remifentanil + Active tDCS Active tDCS * tDCS session: the procedure will initiate by placing an anode electrode on the primary motor cortex (contralateral to the dominant cortex) and the cathode electrode on the contralateral supra-orbital region. The current employed is 2mA of transcranial direct-current stimulation administered for 20 minutes. * Remifentanil - 0,06mcg.kg.min - Infusion 10min before the tDCS session, during the tDCS session and after the tDCS session, until the end of pain tests. Remifentanil + Sham tDCS Sham tDCS * Sham tDCS: consists in the same montage of the active tDCS, but the device is turned off 30 seconds after starting stimulation (without letting the patient notice it). The rest of the montage is kept identical to the active one during the 20 minutes session. * Remifentanil - 0,06mcg.kg.min - Infusion 10min before the tDCS session, during the tDCS session and after the tDCS session, until the end of pain tests. Placebo + Sham tDCS Sham tDCS * Sham tDCS: consists in the same montage of the active tDCS, but the device is turned off 30 seconds after starting stimulation (without letting the patient notice it). The rest of the montage is kept identical to the active one during the 20 minutes session. * Placebo: Saline infusion - Infusion 10min before the tDCS session, during the tDCS session and after the tDCS session, until the end of pain tests. Placebo + Active tDCS Placebo * tDCS session: the procedure will initiate by placing an anode electrode on the primary motor cortex (contralateral to the dominant cortex) and the cathode electrode on the contralateral supra-orbital region. The current employed is 2mA of transcranial direct-current stimulation administered for 20 minutes. * Placebo: Saline infusion - Infusion 10min before the tDCS session, during the tDCS session and after the tDCS session, until the end of pain tests. Placebo + Sham tDCS Placebo * Sham tDCS: consists in the same montage of the active tDCS, but the device is turned off 30 seconds after starting stimulation (without letting the patient notice it). The rest of the montage is kept identical to the active one during the 20 minutes session. * Placebo: Saline infusion - Infusion 10min before the tDCS session, during the tDCS session and after the tDCS session, until the end of pain tests. Remifentanil + Active tDCS Remifentanil * tDCS session: the procedure will initiate by placing an anode electrode on the primary motor cortex (contralateral to the dominant cortex) and the cathode electrode on the contralateral supra-orbital region. The current employed is 2mA of transcranial direct-current stimulation administered for 20 minutes. * Remifentanil - 0,06mcg.kg.min - Infusion 10min before the tDCS session, during the tDCS session and after the tDCS session, until the end of pain tests. Remifentanil + Sham tDCS Remifentanil * Sham tDCS: consists in the same montage of the active tDCS, but the device is turned off 30 seconds after starting stimulation (without letting the patient notice it). The rest of the montage is kept identical to the active one during the 20 minutes session. * Remifentanil - 0,06mcg.kg.min - Infusion 10min before the tDCS session, during the tDCS session and after the tDCS session, until the end of pain tests.
- Primary Outcome Measures
Name Time Method Thresholds of pain to the cold pressor test (CPT) 20min
- Secondary Outcome Measures
Name Time Method Serum levels of BDNF 20min Threshold of pain to the thermal stimulus (TT) 20min Intensity of electrical brain activity in the bi-spectral index (BIS) 60min Sedation level in the visual analogue scale (VAS) 60min Conditioned pain modulation (CPM) 20min A nociceptive tonic conditioning stimulus - immersion of the non-dominant hand in cold water (0°C for 1 minute) - will be applied concomitant to the progressive thermal stimulus in the dominant forearm as applied in the QST pattern until it reaches the 6/10 pain temperature previously determined by the participant.
Temperature of tolerance to the thermal stimulus (TTTS) 20min Hemodynamic changes of brain using fNIRSNear-infrared spectroscopy (NIRS) 60 The vascular response will be assessed using functional near infrared spectroscopy (fNIRS). Emerging technique that allows the functional mapping of the brain, with a better understanding of the neuro-vascular coupling, the neurophysiological fluctuations and cerebral hemodynamics.
Trial Locations
- Locations (1)
Hospital de Clinicas e Porto Alegre (HCPA)
🇧🇷Porto Alegre, Rio Grande do Sul, Brazil