ClinicalTrials.gg
Status unknownNCT03826407Updated Feb 6, 2023

Development of a Point of Care System for Automated Coma Prognosis

An observational study in Coma, Disorder of Consciousness and Minimally Conscious State, sponsored by McMaster University. Status unknown at 1 site in Canada. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2023-02-06.

Sponsored by McMaster University · Observational

The sponsor has not verified this record recently (last verified Feb 2023), so the status shown — last known as Active, not recruiting — may be out of date.
Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
33
Ages
18 Years and older
Sex
All
01

Study summary

Electroencephalogram/event-related potentials (EEG/ERP) data will be collected from 50 participants in coma or other disorder of consciousness (DOC; i.e., Unresponsive Wakefulness Syndrome [UWS] or Minimally Conscious State [MCS]), clinically diagnosed using the Glasgow Coma Scale (GCS). For coma patients, EEG recordings will be conducted for up to 24 consecutive hours at a maximum of 5 timepoints, spanning 30 days from the date of recruitment, to track participants' clinical state. For DOC patients, there will be an initial EEG recording up to 24 hours, with possible subsequent weekly recordings up to 2 hours. An additional dataset from 40 healthy controls will be collected, each spanning up to a 12-hour recording period in order to formulate a baseline. Collected data are to form the basis for automatic analysis and detection of ERP components in DOC, using a machine learning paradigm. Salient features (i.e., biomarkers) extracted from the ERPs and resting-state EEG will be identified and combined in an optimal fashion to give an accurate indicator of prognosis.

Read the detailed description

The Problem: Coma is a state of unconsciousness with a variety of causes. Traditional tests for coma outcome prediction are mainly based on a set of clinical observations (e.g., pupillary constriction). Recently however, event-related potentials (ERPs; which are transient electroencephalogram [EEG] responses to auditory, visual, or tactile stimuli) have been introduced as useful predictors of a positive coma outcome (i.e., emergence). However, such tests require a skilled neurophysiologist, and such people are in short supply. Also, none of the current approaches has sufficient positive and negative predictive accuracies to provide definitive prognoses in the clinical setting.

Objective: The investigators will apply innovative machine learning methods to analyze patient EEGs (50 patients and 40 healthy controls) to develop a simple, objective, replicable, and inexpensive point of care system which can significantly improve the accuracy of coma prognosis relative to current methods. The physical requirements of the proposed system consist only of an EEG system (inexpensive in terms of medical equipment) and a conventional laptop computer.

Methodology: The investigators intend to extend the team's newest algorithms and develop machine learning tools for automatic analysis and detection of ERP components. Preliminary results by the team in this respect have been very promising. The most salient features (i.e., biomarkers) extracted from the ERP will be identified and combined in an optimal fashion to give an accurate indicator of prognosis. Features will be extracted from resting state brain networks and from network trajectories associated with the processing of ERP signals.

Significance: The proposed work will enable critical care physicians to assess coma prognosis with speed and accuracy. Thus, families and their health care team will be provided the most accurate information possible to guide discussions of goals of care and life-sustaining therapies in the context of dealing with the consequences of devastating neurological injury.

02

Conditions studied

  • Coma
  • Disorder of Consciousness
  • Minimally Conscious State
  • Vegetative State
  • Neuropathology

Keywords

  • Coma
  • Machine Learning
  • Prognosis
  • Electrophysiology
  • Event-related potentials
  • Electroencephalography
  • Mismatch Negativity
  • Auditory Brainstem Response
  • Disorders of Consciousness
  • EEG
  • ERP
03

In context

Coma

138 studies on the registry are indexed under Coma; 35 are open to participants now.

This study's enrollment of 33 is below the median of 100 across 58 observational studies indexed under Coma.

Browse Coma studies →

Lead sponsor

McMaster University is the lead sponsor of 741 studies on the registry; 127 are open to participants now.

Of its 7 completed or terminated interventional studies of FDA-regulated products, 3 (43%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
Yes
Sampling method
Non-probability sample

Study population

The Coma/DOC Group will include 50 patients from the Intensive Care Units, Neurological Step Down Unit, or Coronary Care Unit at Hamilton General Hospital (Ontario, Canada) who are in coma (GCS score =3-8), or who have other disorders of consciousness (MCS or UWS).

The Control Group of 40 matched healthy controls will be recruited primarily from the Hamilton community (Ontario, Canada).

Eligibility criteria

Inclusion Criteria:

  • Patients (≥ 18 years of age) primarily admitted to the Intensive Care Units, Neurological Step Down Unit, or Coronary Care Unit at Hamilton General Hospital who are in coma with Glasgow Coma Scale (GCS) score of 3-8, or;
  • Patients (≥ 18 years of age) who have other disorders of consciousness, primarily Minimally Conscious State (MCS) or Unresponsive Wakefulness Syndrome (UWS; also known as vegetative state).

Exclusion Criteria:

  • Severe liver failure (i.e., Class C)
  • Severe renal failure (i.e., Urea ≥ 40)
  • Previous open-head injury
  • Known primary and secondary central nervous system
  • Known hearing impairment
  • Previous intracranial pathology requiring neurosurgical interventions in the past 72 hours
  • Anyone who is deemed medically unsuitable for this study by the attending intensivists

Healthy Controls:

Inclusion:

  • ≥ 18 years of age
  • no visual, language, learning, or hearing problems
  • no history of neurological or psychiatric disorder
  • not currently taking any medications that act on the central nervous system, such as antidepressants, anxiolytics, or anti-epileptics

Exclusion:

(During the COVID-19 pandemic only)

  • ≥ 60 years of age
  • have a weakened immune system
  • have one or more of the COVID-19 high risk medical conditions, according to the government of Canada website: https://www.canada.ca/en/public-health/services/publications/diseases-conditions/people-high-risk-for-severe-illness-covid-19.html.
Terms in these criteria, in plain language(2)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Child-Pugh class

A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

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Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
33 participants (actual)
Patient registry
No

Groups and cohorts

  • DOC patients

    Patients in coma (GCS score of 3-8) or with other disorder of consciousness, primarily Minimally Conscious State (MCS) or Unresponsive Wakefulness Syndrome (UWS; also known as vegetative state)

  • Healthy Control

    Matched healthy controls without current neurological diagnoses

06

What researchers measure

Primary outcomes

  1. Change in multiple electrophysiological measures across specified time points during coma

    Event-related potentials (ERP) and resting state periods will be assessed at the specified intervals as a difference between successive timepoints. The ERP measures will include amplitude and latency values of N1, P2, MMN, P3a, P3b, and N400 to assess different levels of conscious processing and presence of signs of a conscious state predictive of subsequent emergence. Also, resting EEG measures will be obtained at regular intervals. EEG/ERP data will be recorded for up to 24 consecutive hours at a maximum of 5 timepoints spanning 30 days from the date of recruitment to track the participants' progression. The date of the initial assessment will be denoted as Day 0, and the subsequent assessments will take place ideally on Day 3, Day 10, Day 20 and Day 30, unless there is a ≥ 2 point of change in the patient's GCS score. Change in all specified measures will be assessed across the up to 24-hour recordings taken at 5 different timepoints.

    Time frame: up to 30 days from date of recruitment

  2. Change in multiple electrophysiological measures across specified time points during MCS or UWS

    Event-related potentials (ERP) and resting state periods will be assessed at the specified intervals as a difference between successive timepoints. The ERP measures will include amplitude and latency values of N1, P2, MMN, P3a, P3b, and N400 to assess different levels of conscious processing and presence of signs of a conscious state predictive of subsequent emergence. Also, resting EEG measures will be obtained at regular intervals. EEG/ERP data will be recorded for an initial period of up to 24 consecutive hours, followed by up to 2-hour long recordings that may be conducted approximately once a week until the patient either regains full consciousness, is no longer within the Hamilton Health Sciences system, or until 6 months from the date of their enrollment into the study, whichever occurs first. Change in all specified measures will be assessed across the recordings taken at each timepoint.

    Time frame: up to 6 months from date of recruitment

  3. Correlation between behavioral and electrophysiological measures after coma/DOC emergence

    Patient emergence will be monitored using the Glasgow Outcome Scale (GOS). In the case of patient emergence, the full electrophysiological test procedures are recorded to correlate with traditional behavioral measures. The electrophysiological measures obtained at this timepoint (emergence) will be compared to the same measures obtained at the different time points during coma/DOC (Outcome 1/2) to detect both clinically relevant change and possible prognostic markers that may have been obtained at an earlier test point.

    Time frame: Within a 30-day time period post recruitment

  4. Sensitivity and specificity of prognostic capabilities of electrophysiological measures

    Analyses will compare the electrophysiological measures as outcome predictors to traditional behaviorally-based tools.

    Time frame: Within a 30-day time period post recruitment

  5. Feasibility of procedure

    The team will also evaluate whether the repeated EEG sessions, lasting up to 24 hours, during the coma/DOC duration is a feasible approach to predict the emergence and outcome from coma.

    Time frame: up to 6 months from date of recruitment

Secondary outcomes

  1. Correlation between individual patient factors, EEG results, and outcome for coma

    The study also collects demographic, medical history, injury information, and other physiological markers from the patient's health record and concurrent physiological assessment during the study period. Analyses will assess correlations between these factors and coma outcome and EEG findings.

    Time frame: up to 30 days from date of recruitment

  2. Correlations between individual patient factors, EEG results, and outcome for DOC

    The study also collects demographic, medical history, injury information, and other physiological markers from the patient's health record and concurrent physiological assessment during the study period. Analyses will assess correlations between these factors and DOC outcome and EEG findings.

    Time frame: up to 6 months from date of recruitment

07

Study locations

1 site
  • McMaster University Hamilton Health Sciences / Hamilton General Hospital
    Hamilton, Ontario L8L 2X2, Canada
08

References and documents

Publications

  • Jones C. Glasgow coma scale. Am J Nurs. 1979 Sep;79(9):1551-3. No abstract available. PubMed 258560 ↗
  • Chiappa KH, Hill RA. Evaluation and prognostication in coma. Electroencephalogr Clin Neurophysiol. 1998 Feb;106(2):149-55. doi: 10.1016/s0013-4694(97)00118-1. PubMed 9741776 ↗
  • de Sousa LC, Colli BO, Piza MR, da Costa SS, Ferez M, Lavrador M. Auditory brainstem response: prognostic value in patients with a score of 3 on the Glasgow Coma Scale. Otol Neurotol. 2007 Apr;28(3):426-8. doi: 10.1097/MAO.0b013e3180326170. PubMed 17303965 ↗
  • Logi F, Fischer C, Murri L, Mauguiere F. The prognostic value of evoked responses from primary somatosensory and auditory cortex in comatose patients. Clin Neurophysiol. 2003 Sep;114(9):1615-27. doi: 10.1016/s1388-2457(03)00086-5. PubMed 12948790 ↗
  • Lew HL, Poole JH, Castaneda A, Salerno RM, Gray M. Prognostic value of evoked and event-related potentials in moderate to severe brain injury. J Head Trauma Rehabil. 2006 Jul-Aug;21(4):350-60. doi: 10.1097/00001199-200607000-00006. PubMed 16915010 ↗
  • Kane NM, Butler SR, Simpson T. Coma outcome prediction using event-related potentials: P(3) and mismatch negativity. Audiol Neurootol. 2000 May-Aug;5(3-4):186-91. doi: 10.1159/000013879. PubMed 10859412 ↗
  • Morlet D, Fischer C. MMN and novelty P3 in coma and other altered states of consciousness: a review. Brain Topogr. 2014 Jul;27(4):467-79. doi: 10.1007/s10548-013-0335-5. Epub 2013 Nov 27. PubMed 24281786 ↗
  • Fischer C, Morlet D, Bouchet P, Luaute J, Jourdan C, Salord F. Mismatch negativity and late auditory evoked potentials in comatose patients. Clin Neurophysiol. 1999 Sep;110(9):1601-10. doi: 10.1016/s1388-2457(99)00131-5. PubMed 10479027 ↗
  • Holeckova I, Fischer C, Giard MH, Delpuech C, Morlet D. Brain responses to a subject's own name uttered by a familiar voice. Brain Res. 2006 Apr 12;1082(1):142-52. doi: 10.1016/j.brainres.2006.01.089. PubMed 16703673 ↗
  • Garrido MI, Kilner JM, Stephan KE, Friston KJ. The mismatch negativity: a review of underlying mechanisms. Clin Neurophysiol. 2009 Mar;120(3):453-63. doi: 10.1016/j.clinph.2008.11.029. Epub 2009 Jan 31. PubMed 19181570 ↗
  • Sonnadara RR, Alain C, Trainor LJ. Occasional changes in sound location enhance middle latency evoked responses. Brain Res. 2006 Mar 3;1076(1):187-92. doi: 10.1016/j.brainres.2005.12.093. Epub 2006 Feb 17. PubMed 16487494 ↗
  • Duncan CC, Barry RJ, Connolly JF, Fischer C, Michie PT, Naatanen R, Polich J, Reinvang I, Van Petten C. Event-related potentials in clinical research: guidelines for eliciting, recording, and quantifying mismatch negativity, P300, and N400. Clin Neurophysiol. 2009 Nov;120(11):1883-1908. doi: 10.1016/j.clinph.2009.07.045. Epub 2009 Sep 30. PubMed 19796989 ↗
  • Schnakers C, Vanhaudenhuyse A, Giacino J, Ventura M, Boly M, Majerus S, Moonen G, Laureys S. Diagnostic accuracy of the vegetative and minimally conscious state: clinical consensus versus standardized neurobehavioral assessment. BMC Neurol. 2009 Jul 21;9:35. doi: 10.1186/1471-2377-9-35. PubMed 19622138 ↗
  • Guldenmund P, Stender J, Heine L, Laureys S. Mindsight: diagnostics in disorders of consciousness. Crit Care Res Pract. 2012;2012:624724. doi: 10.1155/2012/624724. Epub 2012 Nov 14. PubMed 23213492 ↗
  • Giacino JT, Fins JJ, Laureys S, Schiff ND. Disorders of consciousness after acquired brain injury: the state of the science. Nat Rev Neurol. 2014 Feb;10(2):99-114. doi: 10.1038/nrneurol.2013.279. Epub 2014 Jan 28. PubMed 24468878 ↗
  • Laureys S, Celesia GG, Cohadon F, Lavrijsen J, Leon-Carrion J, Sannita WG, Sazbon L, Schmutzhard E, von Wild KR, Zeman A, Dolce G; European Task Force on Disorders of Consciousness. Unresponsive wakefulness syndrome: a new name for the vegetative state or apallic syndrome. BMC Med. 2010 Nov 1;8:68. doi: 10.1186/1741-7015-8-68. PubMed 21040571 ↗
  • Armanfard N, Komeili M, Reilly JP, Mah R, Connolly JF. Automatic and continuous assessment of ERPs for mismatch negativity detection. Annu Int Conf IEEE Eng Med Biol Soc. 2016 Aug;2016:969-972. doi: 10.1109/EMBC.2016.7590863. PubMed 28268485 ↗
  • Ghosh-Dastidar S, Adeli H, Dadmehr N. Principal component analysis-enhanced cosine radial basis function neural network for robust epilepsy and seizure detection. IEEE Trans Biomed Eng. 2008 Feb;55(2 Pt 1):512-8. doi: 10.1109/TBME.2007.905490. PubMed 18269986 ↗
  • Guler I, Ubeyli ED. Multiclass support vector machines for EEG-signals classification. IEEE Trans Inf Technol Biomed. 2007 Mar;11(2):117-26. doi: 10.1109/titb.2006.879600. PubMed 17390982 ↗
  • Cao C, Tutwiler RL, Slobounov S. Automatic classification of athletes with residual functional deficits following concussion by means of EEG signal using support vector machine. IEEE Trans Neural Syst Rehabil Eng. 2008 Aug;16(4):327-35. doi: 10.1109/TNSRE.2008.918422. PubMed 18701381 ↗
  • Ravan M, Hasey G, Reilly JP, MacCrimmon D, Khodayari-Rostamabad A. A machine learning approach using auditory odd-ball responses to investigate the effect of Clozapine therapy. Clin Neurophysiol. 2015 Apr;126(4):721-30. doi: 10.1016/j.clinph.2014.07.017. Epub 2014 Aug 27. PubMed 25213349 ↗
  • Khodayari-Rostamabad A, Reilly JP, Hasey GM, de Bruin H, Maccrimmon DJ. A machine learning approach using EEG data to predict response to SSRI treatment for major depressive disorder. Clin Neurophysiol. 2013 Oct;124(10):1975-85. doi: 10.1016/j.clinph.2013.04.010. Epub 2013 May 15. PubMed 23684127 ↗
  • Wijdicks EF, Bamlet WR, Maramattom BV, Manno EM, McClelland RL. Validation of a new coma scale: The FOUR score. Ann Neurol. 2005 Oct;58(4):585-93. doi: 10.1002/ana.20611. PubMed 16178024 ↗
  • Jennett B, Bond M. Assessment of outcome after severe brain damage. Lancet. 1975 Mar 1;1(7905):480-4. doi: 10.1016/s0140-6736(75)92830-5. PubMed 46957 ↗
  • Armanfard N, Reilly JP, Komeili M. Local Feature Selection for Data Classification. IEEE Trans Pattern Anal Mach Intell. 2016 Jun;38(6):1217-27. doi: 10.1109/TPAMI.2015.2478471. Epub 2015 Sep 14. PubMed 26390448 ↗
  • Armanfard N, Reilly JP, Komeili M. Logistic Localized Modeling of the Sample Space for Feature Selection and Classification. IEEE Trans Neural Netw Learn Syst. 2018 May;29(5):1396-1413. doi: 10.1109/TNNLS.2017.2676101. Epub 2017 Mar 21. PubMed 28333643 ↗
  • Connolly JF, Reilly JP, Fox-Robichaud A, Britz P, Blain-Moraes S, Sonnadara R, Hamielec C, Herrera-Diaz A, Boshra R. Development of a point of care system for automated coma prognosis: a prospective cohort study protocol. BMJ Open. 2019 Jul 17;9(7):e029621. doi: 10.1136/bmjopen-2019-029621. PubMed 31320356 ↗

Individual participant data

Plan to share: Undecided — To be decided

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Ran from Oct 2019 to primary completion in Aug 2022, 34 months.

Of 24 observational studies under Coma, half reached primary completion within 34 months of starting (the median), counting those still running; a quarter within 14 and three quarters within 60. This study's 34 months is close to that.

How these figures are worked out, and which studies are left out of them.

Registered
Jan 18, 2019
First posted
Feb 1, 2019
StartActual
Oct 1, 2019
Primary completionActual
Aug 12, 2022
CompletionEst.
Dec 2023
Last update
Feb 6, 2023
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Feb 6, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT03826407
Collaborators
Canadian Institutes of Health Research (CIHR), Natural Sciences and Engineering Research Council, Canada, Hamilton Health Sciences Corporation, Brain Vision Solutions Inc., McGill University
Responsible party
Sponsor
First posted
Feb 1, 2019
Start date
Oct 1, 2019
Primary completion
Aug 12, 2022
Completion
Dec 2023 (estimated)
Last update
Feb 6, 2023

Study contacts

John F Connolly, PhD
principal investigator · McMaster University
Alison Fox-Robichaud, MD
study chair · Hamilton Health Sciences - Hamilton General site

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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