Comatose, Critical Care, Prognosis
Conditions
Keywords
Prognostication, Somatosensory evoked - potentials, Neurocritical care, Machine learning, Continuous EEG
Brief summary
The main aim of this study is to develop a new technique for the passive diagnosis of cognitive-motor dissociation, with the detection of motor intention in a comatose patient by analysing the EEG signal and in particular the ERD/ERS amplitudes in the motor cortex after stimulation of the median nerve.
Detailed description
The utilisation of brain-computer interfaces (BCI) employing median nerve stimulation has the potential to yield novel insights into the enhancement of neuroprognostication. The application of painless, low-intensity electrical stimulation to the median nerve has been shown to activate the somatosensory cortex and the motor cortex via cutaneous and proprioceptive afferents. The activation in question has been shown to induce specific modulations of the electroencephalogram (EEG) signal, characterised by event-related desynchronisation (ERD) during stimulation, followed by resynchronisation (ERS) afterwards. The application of this stimulation during a motor task - that is to say, voluntary movement or motor imagery - results in a marked attenuation of post-stimulation ERS, or even its complete absence. The intention to move a hand, when coinciding with median nerve stimulation, amplifies the cortical ERD/ERS signatures, and is made more easily detectable by machine learning algorithms. The main aim of this study is to develop a new technique for the passive diagnosis of cognitive-motor dissociation, with the detection of motor intention in a comatose patient by analysing the EEG signal and in particular the ERD/ERS amplitudes in the motor cortex after stimulation of the median nerve.
Interventions
OTHEREEGs
All patients included in the study will receive electroencephalograms (EEGs) of post-stimulation event-related desynchronisation (ERD)/event-related synchronisation (ERS) amplitudes of the median nerve on two occasions per week. These recordings will be made twice a day, once in the morning and once in the afternoon/evening, in order to take account of the patients' inherent nycthemeral rhythm. A recording of 12 EEG electrodes from the scalp will be made during painless stimulation of the median nerve. The intensity of this stimulation will range from 3 to 14 mA, with a duration of 0.1 ms and a frequency of 5 Hz. This will result in a multiplication of the recording periods during and after stimulation. A final period of approximately 15 minutes of recording will be carried out with headphones on the patient, using simple, pre-recorded, standardized commands. These recordings will be continued for a period of three weeks following their inclusion.
Sponsors
University Hospital, Bordeaux
Inria, the French National Institute for computer science and applied mathematics
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
This prospective interventional study involves the use of passive somaesthetic stimulation, which is defined as painless electrical stimulation of the median nerve, in conjunction with electroencephalogram (EEG) recordings. The study is being conducted in a single centre, specifically the neuro-resuscitation department of the Pellegrin Hospital in Bordeaux
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Patients must be aged 18 years or over; * Patients must be admitted to the intensive care unit with a cerebrovascular pathology; * Patients must be in a comatose state with a Glasgow score strictly less than 8, 24 hours after stopping sedation. * Representative of the patient informed of the research and not objecting to it, information and collection of the participant's non-objection if recovery of the ability to understand the content of the information note, * The patient is a recipient of or affiliated with a social security scheme.
Exclusion criteria
* Bilateral lesions of the motor cortex or cortico-spinal fasciculus, * Cutaneous infection of the scalp or any other lesion making surface electroencephalography impossible, * Patient whose short-term survival (48 - 72 hours) seems compromised, * Severe peripheral neuromyopathy, * Severe Acute Respiratory Distress Syndrome at the time of screening, * Hearing-impaired patients with hearing aids, * Pregnant or breastfeeding woman, * Patient under legal protection (persons deprived of their liberty or under guardianship).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Alterations in the electroencephalogram | 3 weeks after inclusion | The alterations in the electroencephalogram (EEG) signal in the event-related desynchronisation/event-related synchronisation cortical signature following median nerve stimulation will be analysed and correlated with the emergence of clinical motor intention. The detection of cognitive-motor dissociation will rely on classification algorithms that detect the presence of motor activity in EEG signals following median nerve stimulation (MNS). The EEG signals recorded immediately after MNS will be represented as one or more covariance matrices, and several classifiers, including Riemannian classifiers, will then be trained on these matrices to classify a state of rest or motor activity in the EEG. |
| CRS-R score | 3 weeks after inclusion | Progression of the Clinical Rating Scale-Revised (CRS-R) score: Standardized clinical scale assessing level of consciousness across six subdomains: auditory, visual, motor, oromotor/verbal, communication, and arousal. Total score: 0 to 23 Interpretation: Lower scores indicate absence or very low levels of consciousness (coma or vegetative state/unresponsive wakefulness syndrome). Intermediate scores indicate minimal but definite behavioral evidence of consciousness (minimally conscious state). Higher scores indicate more complex behaviors consistent with a higher level of consciousness (emergence from the minimally conscious state). |
| Glasgow score | 3 weeks after inclusion | Glasgow Coma Scale (GCS) Standardized clinical scale assessing level of consciousness based on three components: eye opening, verbal response, and motor response. Total score: 3 to 15 Interpretation: Lower scores indicate severe impairment of consciousness (coma or deep unconsciousness). Intermediate scores indicate moderate impairment of consciousness. Higher scores indicate mild or no impairment of consciousness. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| GOS-E | 6 months after inclusion | The functional neurological prognosis in the period subsequent to the event will be evaluated by the Glasgow Outcome Scale-Extended (GOS-E) Standardized clinical scale assessing functional outcome and disability following brain injury, based on overall level of independence and social functioning. Total score: 1 to 8 Interpretation: Lower scores indicate severe disability or death. Intermediate scores indicate moderate disability with some level of independence. Higher scores indicate good recovery with return to independent functioning. |
| SF36 | 6 months after inclusion | The functional neurological prognosis in the period subsequent to the event will be evaluated by the Short Form-36 Health Survey (SF-36) Standardized patient-reported outcome measure assessing health-related quality of life across eight domains: physical functioning, role limitations due to physical health, bodily pain, general health perception, vitality, social functioning, role limitations due to emotional problems, and mental health. Score range: 0 to 100 for each domain (and summary scores) Interpretation: Lower scores indicate poorer health-related quality of life. Higher scores indicate better health-related quality of life. |
Countries
France
Contacts
CONTACTGeoffroy MOUCHEBOEUF, MD
CONTACTGrégoire CANE, MD
PRINCIPAL_INVESTIGATORGeoffroy MOUCHEBOEUF, MD
University Hospital, Bordeaux
STUDY_DIRECTORGrégoire CANE, MD
University Hospital, Bordeaux
STUDY_CHAIRFabien LOTTE
Institut National de Recherche en Informatique et en Automatique
Outcome results
None listed