Transcutaneous Cranial Electrical Stimulation Research Articles

P 4. Cerebral blood flow modulation by transcutaneous cranial electrical stimulation with Limoge’s current

Objectives TCES delivers a high-frequency (166 kHz) pulsed biphasic balanced current with a pulse repetition frequency of 100 Hz with 40% duty cycle through a negative electrode and two positive electrodes over the skull. TCES has a proven ability to potentiate anesthesia and analgesia, although the physiological mechanisms of this effect remain unclear. We hypothesized that the mechanism is a modulation of CBF in the central endogenous opioid system. This study aimed at determining the effects of TCES on CBF to elucidate its physiological mechanism. Methods Thirty-six healthy volunteers were randomly assigned to active or placebo TCES, and all assessments were double blind. TCES was performed using the Anesthelec™ device. In the stimulated group, an active cable was used, and in the control group (sham), the cable was inactive. CBF was measured by XeCT™ before and after two hours of TCES. Results Globally, CBF was unchanged by TCES. However, locally, TCES induced a significant CBF decrease in the brainstem and thalamus, which are structures involved in pain and anxiety (TCES and control CBF decrease were 18.5 and 11.9 mL/100 g brain tissue/min, respectively). Conclusion TCES can modulate local CBF but it has no effect on overall CBF. [Clinical Trials.gov number: NCT00273663].

P 203. A historical development of transcranial electrical stimulation: Dose development from 1900 to contemporary approaches

Transcranial Electrical Stimulation (TES) encompasses all forms of non-invasive current application to the brain in regards to research and clinical applications. Approaches to TES have evolved in both terminology and dosage over the past 100 years of research. We outline the dose and historical development of TES since 1900 through modern approaches. Contemporary transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) and NeuroElectric Therapy (NET) descended from Electrosleep (ES) while others like Transcutaneous Cranial Electrical Stimulation (TCES), and Limoge, descended from Electroanesthesia (EA). Contemporary approaches such as transcranial Direct Current Stimulation (tDCS) and transcranial Alternating Current Stimulation (tACS) have historical analogues. We consider the role of seminal conferences and medical device regulations in the evolution of techniques and terminology. Select commercial devices and brands are noted for context. We clarify and disambiguate TES terminology including varied conventions across countries, and non-TES techniques. Understanding the roots of contemporary TES approaches in comparable approaches spanning decades, as well as the resurgence and abandonment of past techniques, may inform ongoing TES research.

Cerebral blood flow modulation by transcutaneous cranial electrical stimulation with Limoge's current

Transcutaneous cranial electrical stimulation (TCES) delivers a high-frequency (166 kHz) pulsed biphasic balanced current with a pulse repetition frequency of 100 Hz with 40% duty cycle through a negative electrode and two positive electrodes over the skull. TCES has a proven ability to potentiate anesthesia and analgesia, although the physiological mechanisms of this effect remain unclear. We hypothesized that the mechanism is a modulation of CBF in the central endogenous opioid system. This study aimed at determining the effects of TCES on CBF to elucidate its physiological mechanism. Thirty-six healthy volunteers were randomly assigned to active or placebo TCES, and all assessments were double blind. TCES was performed using the Anesthelec™ device. In the stimulated group, an active cable was used, and in the control group (sham), the cable was inactive. CBF was measured by XeCT™ before and after two hours of TCES. Globally, CBF was unchanged by TCES. However, locally, TCES induced a significant CBF decrease in the brainstem and thalamus, which are structures involved in pain and anxiety (TCES and control CBF decrease were 18.5 and 11.9 mL/100g brain tissue/min, respectively). TCES can modulate local CBF but it has no effect on overall CBF. [Clinical Trials. gov number: NCT00273663].

Comparisons of the effects of acupuncture, electroacupuncture, and transcutaneous cranial electrical stimulation on the minimum alveolar concentration of isoflurane in dogs

To compare the effects of acupuncture (AP), electroacupuncture (EA), and transcutaneous cranial electrical stimulation (TCES) with high-frequency intermittent currents on the minimum alveolar concentration (MAC) of isoflurane and associated cardiovascular variables in dogs. 8 healthy adult female Beagles. Each dog was anesthetized with isoflurane on 4 occasions, allowing a minimum of 10 days between experiments. Isoflurane MAC values were determined for each dog without treatment (controls) and after treatment with AP and EA (AP points included the Large Intestine 4, Lung 7, Governing Vessel 20, Governing Vessel 14, San Tai, and Baihui) and TCES. Isoflurane MAC values were determined by use of noxious electrical buccal stimulation. Heart rate, mean arterial blood pressure (MAP), arterial blood oxygen saturation (Spo2) measured by use of pulse oximetry, esophageal body temperature, inspired and expired end-tidal isoflurane concentrations, end-tidal carbon dioxide concentration, and bispectral index (BIS) were monitored. Blood samples were collected for determination of plasma cortisol concentration. Mean +/- SD baseline MAC of isoflurane was 1.19 +/- 0.1%. Acupuncture did not significantly change MAC of isoflurane. Treatments with EA and TCES significantly lowered the MAC of isoflurane by 10.1% and 13.4%, respectively. The Spo2, heart rate, MAP, BIS, esophageal body temperature, and plasma cortisol concentration were not significantly different after AP, EA, TCES, and control treatments at any time interval. Use of EA and TCES decreased MAC of isoflurane in dogs without inducing adverse hemodynamic effects. However, the reduction in isoflurane MAC by EA andTCES treatments was not considered clinically relevant.

Improvement of Postoperative Analgesia During Cancer Surgery with Limoge's Current: A Personal Experience

The anesthesiologist took advantage of a personal experience to determine whether transcutaneous cranial electrical stimulation using Limoge's current (TCES-LC) improved the level of postoperative analgesia by potentiating anesthetic agents used during the intra- and postoperative phases. Included were analgesics injected through an epidural thoracic catheter (T8-T9) positioned at the end of an esophagectomy. Another reason for a self-experimentation was to be able to evaluate the psycholeptic effects of TCES-LC to gain a better understanding of the problems linked with pain during treatment. The Limoge' current is bidirectional and consists of a high-frequency biphasic asymmetrical wave composed of modulated, high-frequency (166-kHz) pulse trains with a repetition cycle of 100 Hz. TCES-LC was initiated 2 hours before anesthetic induction without any tranquilizer or other medication. TCES-LC was continuously applied during the entire surgical procedure and continued 48 hours postoperatively in the intensive care unit (ICU). As the objective was not to obtain electrical anesthesia, the usual anesthetic protocol was used during surgery. During the initial 48 postoperative hours with continuous application of TCES-LC (D0-D1), a decrease of the epidural anesthetic dose requirement was observed for ropivacaine, and sufentanil (-25% and -60% respectively). A similar decrease in these medications was also measured on day 2 (D2), while TCESLC was terminated. This decrease was amplified day 3 (D3) for both ropivacaine and sufentanil (-50% and -73% respectively). On day 4 (D4) the epidural anesthetics were totally suppressed (1 day before the normal conventional schedule planned for by the ICU physician with this type surgery). Future clinical trials need to be conducted to show the significant advantages of TCES-LC in alternative and complementary medicine.

Transcranial Electrical Stimulation with Limoge's Currents Decreases Halothane Requirements in Rats Evidence for the Involvement of Endogenous Opioids

Transcutaneous cranial electrical stimulation with Limoge's currents has been shown to facilitate anesthesia/analgesia in surgical patients. However, the neurobiologic substrate of this effect remains unknown. The present study was designed to analyze the influence of transcranial electrical stimulation (TCES) on halothane requirements in rats and the contribution of the central endogenous opioid, alpha 2-adrenergic and 5-hydroxytryptamine (5-HT1 and 5-HT2) serotonergic systems to this effect. The influence of TCES on the MAC of halothane (MACH) and its reversibility by a subcutaneous 2 mg/kg naloxone injection were first determined in 20 rats using a randomized blinded protocol. MACH was decreased markedly in stimulated animals (TCES, n = 10) in comparison with sham-operated nonstimulated rats (controls, n = 10): MACH = 0.60 +/- 0.15, mean +/- SD, versus 1.07 +/- 0.05 vol%, P less than 0.001. In TCES animals, naloxone administration restored MACH values to the levels of controls but failed to affect MACH in controls. The influence of the duration of TCES applied prior to MACH determination was further investigated in 30 animals. The magnitude of MACH reduction was significantly increased with the cumulative duration of stimulation. For each duration of stimulation tested, administration of a 5-micrograms intracerebroventricular (icv) dose of the enkephalinase inhibitor thiorphan significantly enhanced TCES effects (P less than 0.05). Finally, the icv administration of a 15-micrograms naloxone dose appeared to reverse completely the MACH reduction elicited by TCES (n = 8, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Transcranial electrical stimulation with high frequency intermittent current (Limoge's) potentiates opiate-induced analgesia: blind studies

Transcutaneous cranial electrical stimulation (TCES) with high frequency (166 kHz) intermittent current (100 Hz; Limoge current) has been used for several years in cardiac, thoracic, abdominal, urological and micro-surgery. The main benefits are a reduced requirement for analgesic drugs, especially opiates, and a long-lasting postoperative analgesia. We have confirmed these clinical observations in rats using the tail-flick latency (TFL) test to measure pain threshold. TCES was not found to modify the pain threshold in drug-free rats, but it potentiated morphine-induced analgesia (systemic injection). To obtain a maximal effect, the stimulation must be initiated 3 h before the drug injection and be maintained throughout the duration of its pharmacological action. TCES potentiation was found to depend on the dose of the drug, the intensity of the current and the polarity of electrodes. These findings were confirmed by blind tests of the efficiency of TCES on several opiate analgesic drugs currently used in human surgery (morphine, fentanyl, alfentanil and dextromoramide). The analgesic effect of these 4 opiates (TFL as % of baseline without or with TCES) were respectively: 174%, 306%; 176%, 336%; 160%, 215%; and 267%, 392%. The results were obtained not only after systemic opiate treatment, but also after intracerebroventricular injection of morphine (10 μg; analgesic effect 152%, 207% with TCES) suggesting that TCES potentiation of opiate-induced analgesia is centrally mediated.

Electrostimulation cérébrale transcutanée par les courants de Limoge au cours de l'accouchement

In order to test the analgesic efficacy of Anesthelec (transcutaneous cranial electrical stimulation with Limoge currents) during labour and delivery, a double blind study was performed in 20 cases for whom analgesia was necessary. In 10 cases Anesthelec was used with the Limoge currents on and in 10 cases as a sham. Labour and delivery were carried out by a medical team different from that which set up the Anesthelec. The results showed that this method, with or without nitrous oxide inhalation, decreased by 80% the number of epidural and general anaesthesias that would otherwise have been unavoidable. To define the effects of this new method, maternal and foetal parameters of 50 deliveries carried out under Anesthelec were compared with 50 deliveries carried out under epidural analgesia. Anesthelec was used only if analgesia was required. This study was a retrospective comparison between two similar non paired series. Despite the fact that analgesia obtained with Anesthelec was less powerful than with epidural analgesia, this method showed many advantages : total safety for the child and the mother, easy utilization, shorter labour time, decreased number of instrumental extractions and potentially reduced costs. Good acceptance and satisfaction for the mother should allow a rapid evolution of this new method.

Transcutaneous cranial electrical stimulation experimental pain and plasma B-endorphin in man

Transcutaneous cranial electrical stimulation experimental pain and plasma B-endorphin in man

Transcutaneous Cranial Electrical Stimulation Decreases Narcotic Requirements During Neurolept Anesthesia and Operation in Man

The influence of transcutaneous cranial electrical stimulation (TCES) on fentanyl requirements was evaluated in 50 patients undergoing urologic operations with pure neuroleptanesthesia (droperidol, diazepam, fentanyl, and air oxygen) with (group I) or without (group II) simultaneous TCES. All patients had silver electrodes (three) applied between the eyebrows and behind each mastoid process and attached to a 167-kHz current generator. Current was delivered only to group I. The wave form was a complex nonsinusoidal, nonsquare wave pattern which was applied intermittently in a 3-msec-on 10-msec-off sequence. All patients had anesthesia induced with droperidol (0.20 mg/kg IV), diazepam (0.2 mg/kg IV), and pancuronium (0.08 mg/kg IV), and, after tracheal intubation, had anesthesia maintained with fentanyl in 100-microgram intravenous increments every 3 minutes whenever and as long as systolic arterial blood pressure and/or heart rate were greater than 20% of control (preanesthetic induction) values. Fentanyl requirements averaged 6.1 +/- 0.5 and 7.9 +/- 0.4 microgram/kg/min for a mean total dosage of 9.0 +/- 0.9 and 12.5 +/- 0.8 microgram/kg for the entire operation in groups I and II, respectively. These differences between groups were statistically significant (p less than 0.05). The data demonstrate that TCES augments the analgesic effects of fentanyl and thus reduces fentanyl requirements during urologic operations with neuroleptanesthesia.

Transcutaneous Cranial Electrical Stimulation Increases the Potency of Nitrous Oxide in Humans

Department of Anestheswlogy, University of Utah School of Medicine, Salt Lake City, Utah; The Necker Hospital, Pans, France; and the Institute De Recherche D'Electroanesthesie, Faculté de Chirurgie-Dentaire, Universite René Déscartes, Montrouge, France

Transcutaneous cranial electrical stimulation increases the potency of nitrous oxide in humans.

The potency, amnesic, and postanesthetic analgesic effects of transcutaneous cranial electrical stimulation (TCES) were evaluated during N2O anesthesia in 120 unpremedicated patients, prior to urologic or general surgical operations. The patients were divided into six groups of 20 each with respect to what concentration of N2O in oxygen they were allowed to breathe (75, 62.5, and 50%), and whether they were or were not stimulated with TCES. Recordings of heart and respiratory rates, systolic arterial blood pressure, and minute ventilation were made prior to and after 20 min of N2O, and one minute later following application of a Kocker clamp to the upper inner thigh for one minute. The presence or absence of movement during the painful stimulus, memory of the painful stimulus, and postanesthetic pain at the clamp site (20 min after anesthesia) were also evaluated. Patients who received TCES had significantly lower incidences of movement, memory of the painful stimulus, and postanesthetic pain at the stimulation site at each N2O concentration than patients not getting TCES. TCES did not alter circulatory and respiratory dynamics prior to painful stimulation and prevented an increase in arterial blood pressure during painful stimulation in patients receiving 50% N2O. These data indicate that TCES significantly increases the analgesic potency of N2O and probably also the depth of anesthesia.

Transcutaneous Cranial Electrical Stimulation Decreases Narcotic Requirements during Neurolept Anesthesia and Operation in Man

Transcutaneous Cranial Electrical Stimulation Decreases Narcotic Requirements during Neurolept Anesthesia and Operation in Man