Journal Article

Modulation of brain activity in brain-injured patients with a disorder of consciousness in intensive care with repeated 10-Hz transcranial alternating current stimulation (tACS): a randomised controlled trial protocol

Williams, Virginie, Arbour, Caroline, Williamson, David, Deshaies, Amelie A, Duclos, Catherine, Maschke, Charlotte, Blain-Moraes, Stefanie, De Beaumont, Louis, Briand, Marie-Michele, De Koninck, Béatrice P, Brazeau, Daphnee, Bernard, Francis

2024

Overview

IntroductionTherapeutic interventions for disorders of consciousness lack consistency; evidence supports non-invasive brain stimulation, but few studies assess neuromodulation in acute-to-subacute brain-injured patients. This study aims to validate the feasibility and assess the effect of a multi-session transcranial alternating current stimulation (tACS) intervention in subacute brain-injured patients on recovery of consciousness, related brain oscillations and brain network dynamics.Methods and analysesThe study is comprised of two phases: a validation phase (n=12) and a randomised controlled trial (n=138). Both phases will be conducted in medically stable brain-injured adult patients (traumatic brain injury and hypoxic-ischaemic encephalopathy), with a Glasgow Coma Scale score ≤12 after continuous sedation withdrawal. Recruitment will occur at the intensive care unit of a Level 1 Trauma Centre in Montreal, Quebec, Canada. The intervention includes a 20 min 10 Hz tACS at 1 mA intensity or a sham session over parieto-occipital cortical sites, repeated over five consecutive days. The current’s frequency targets alpha brain oscillations (8–13 Hz), known to be associated with consciousness. Resting-state electroencephalogram (EEG) will be recorded four times daily for five consecutive days: pre and post-intervention, at 60 and 120 min post-tACS. Two additional recordings will be included: 24 hours and 1-week post-protocol. Multimodal measures (blood samples, pupillometry, behavioural consciousness assessments (Coma Recovery Scale-revised), actigraphy measures) will be acquired from baseline up to 1 week after the stimulation. EEG signal analysis will focus on the alpha bandwidth (8–13 Hz) using spectral and functional network analyses. Phone assessments at 3, 6 and 12 months post-tACS, will measure long-term functional recovery, quality of life and caregivers’ burden.Ethics and disseminationEthical approval for this study has been granted by the Research Ethics Board of the CIUSSS du Nord-de-l’Île-de-Montréal (Project ID 2021–2279). The findings of this two-phase study will be submitted for publication in a peer-reviewed academic journal and submitted for presentation at conferences. The trial’s results will be published on a public trial registry database (ClinicalTrials.gov).Trial registration number NCT05833568.

• Publisher: British Medical Journal Publishing Group,BMJ Publishing Group LTD,BMJ Publishing Group
• Subject: Adult / Adult intensive & critical care / Adult neurology / Brain - physiopathology / Brain Injuries - complications / Brain Injuries - physiopathology / Brain Injuries - therapy / Brain Injuries, Traumatic - complications / Brain Injuries, Traumatic - physiopathology / Brain Injuries, Traumatic - therapy / Brain research / Caregivers / Coma / Consciousness / Consciousness Disorders - etiology / Consciousness Disorders - physiopathology / Consciousness Disorders - therapy / Critical Care - methods / Electric currents / Electroencephalography / Female / Glasgow Coma Scale / Humans / Hypoxia-Ischemia, Brain - physiopathology / Hypoxia-Ischemia, Brain - therapy / Informed consent / Intensive care / Intervention / Male / Neurological injury / Neurology / Neurophysiology / Patients / Quality of life / Randomized Controlled Trials as Topic / Spectrum allocation / Transcranial Direct Current Stimulation - methods / Traumatic brain injury