Skip to main content

Or 34,00 After 66% tax deduction

I make a monthly donation I make an IFI donation
Research, science & health

A multimodal approach to better predict recovery in patients with disorders of consciousness

Published on: 30/05/2024 Reading time: 1 min
Une tête de statue de l'île de Pâques sur laquelle sont posées des éléctrodes

When a patient is admitted to intensive care due to a disorder of consciousness—such as a coma—establishing their neurological prognosis is a crucial yet challenging task. To reduce the uncertainty that precedes the medical decision, a group of clinicians and researchers from the Paris Brain Institute and the Pitié-Salpêtrière Hospital in Paris have assessed the efficacy of a multimodal approach that combines various clinical, electrophysiological, behavioural and neuroimaging indicators. The team's findings, published in Nature Medicine, show that this approach leads to better prognosis.

After a severe cranial trauma or cardiac arrest, some patients admitted to intensive care show little or no reaction to their environment—and are sometimes unable to communicate. This condition is called a disorder of consciousness (DoC), which includes comas, vegetative states and states of “minimal consciousness.”

 

This disorder sometimes persists for several days or weeks. In such cases, healthcare teams and relatives must obtain the most accurate information on the patient's cognitive recovery capacities. Usually, a neurological prognosis is established using several indicators—including standard measurements of brain anatomy (CT and MRI scans) and function (electroencephalogram).

 

Despite having these data at our disposal, there remains a degree of uncertainty about the prognosis, which can significantly impact medical decision-making. These patients are often in a fragile state and prone to numerous complications, which raises questions about the appropriateness of the care they receive,” explains Benjamin Rohaut (AP-HP, Sorbonne University), neurologist, researcher and lead author of the study. “Moreover, doctors sometimes observe a discrepancy between the patient's behaviour and their brain activity: some patients in a vegetative state seem to understand what is being said to them but are unable to let their caregivers know.”

 

To improve the description of the state of consciousness of these patients, the “PICNIC team”, co-led by Lionel Naccache at the Paris Brain Institute, has been working for around fifteen years to define new brain measurements and clinical examination signs. Their approach has gradually evolved towards “multi-modality”, combining PET scans, multivariate EEG analysis, functional MRI, cognitive evoked potentials (electrical responses to sensory stimulation) and other tools.

Consciousness markers under scrutiny

To assess the clinical value of this approach, the team worked with the “Neurologically Oriented Intensive Care Unit” at the Pitié-Salpêtrière Hospital in Paris. Led by Benjamin Rohaut and Charlotte Calligaris (AP-HP), the clinicians and researchers followed and assessed 349 intensive-care patients between 2009 and 2021. At the end of each multimodal evaluation, they formulated a “good”, “uncertain”, or “unfavourable” prognostic opinion.

 

Their results indicate that patients with a “good prognosis” (22% of cases) showed a much more favourable evolution of their cognitive abilities than patients with a prognosis judged “uncertain” (45.5% of cases) or “unfavourable” (32.5% of cases); none of the patients assessed as “unfavourable” regained consciousness after one year. Above all, this prognostic performance was correlated with the number of modalities: the greater the number of indicators used, the greater the accuracy of the prognosis, and the greater the team's confidence in its assessments.

This long-term study shows for the first time the benefit of the multimodal approach, which is essential information for intensive care units worldwide. It also provides empirical validation of the recent recommendations of the European and American Neurology Academies.

Jacobo Sitt (Inserm) Co-supervised this study with Lionel Naccache
Towards a standardised neuroprognostic approach

However, the multimodal approach is not a magic wand. It provides the best possible information to caregivers and families in situations of uncertainty—an ethical advance in patient care—but does not guarantee bias-free decision-making.

Finally, there is the question of access to assessment tools, which are expensive and require specific expertise. “We are aware that multimodal assessment is not accessible to all the intensive care units that receive these patients”, continues Lionel Naccache (Sorbonne University, AP-HP). “We therefore propose to build a network of collaborations at the national and European levels. Thanks to telemedicine tools and automated EEG or brain imaging analysis, all intensive care units could have a first level of access to multimodal assessment. Should this prove insufficient, recourse to a regional expert centre would provide a more in-depth assessment. Finally, in the most complex situations, it would be possible to call on all available experts, wherever they may be. We aim to ensure that all patients with a disorder of consciousness can benefit from the highest standards of neurological prognosis.”

Funding

This study was funded by the James S. McDonnell Foundation, the Foundation for Medical Research (FRM), UNIM, the Lamonica Prize of the French Academy of Sciences, the European Partnership for Personalised Medicine (PerMed), and the Investissements d’avenir program.

Conflict of interest

Jacobo Sitt and Lionel Naccache are co-founders and shareholders of Neurometers, a company dedicated to the medical use of electroencephalogram (EEG) to quantify the brain signatures of consciousness and cognition.

Image

Crédit : Nicolas Decat.

Sources

Rohaut, B., Calligaris, C., … Sitt J.D., Naccache L. Multimodal assessment improves neuroprognosis performance in clinically unresponsive critical care patients with brain injury. Nature Medicine. (Mai 2024).

DOI : 10.1038/s41591-024-03019-1.

Our news on the subject

Interneurones. Crédit : UCLA Broad Stem Cell Research Center.
Stimulating specific neurons in the striatum stops compulsive behaviour
What if we could resist compulsions? These irrational behaviours, particularly common in obsessive-compulsive disorder (OCD), are hard to suppress. At Paris Brain Institute, Éric Burguière's team shows that we can anticipate them and block them ...
09.10.2024 Research, science & health
Les nerfs moteurs présents dans la moelle épinière se projettent vers la périphérie, où ils entrent en contact avec les muscles, formant des connexions appelées jonctions neuromusculaires. Crédit : James N. Sleigh.
Ultrasound show unexpected effects on motor neuron disease
Over the past fifteen years, neurosurgeons have been perfecting a fascinating technique: using ultrasound to temporarily open the blood-brain barrier to facilitate the action of therapeutic molecules in the central nervous system. At Paris Brain ...
09.05.2024 Research, science & health
Un neurone
Rett syndrome: a new gene therapy on the way
Gene therapy could be our best chance of treating Rett syndrome, a neurological disorder that causes severe intellectual and motor impairments. At Paris Brain Institute, Françoise Piguet and her colleagues have looked closely at brain cholesterol ...
07.16.2024 Research, science & health
Lésions d’un patient à l’inclusion dans le protocole (M0) disparues après 2 ans de traitement à la Leriglitazone (M24)
The dual effect of leriglitazone in X-linked Adrenoleukodystrophy (X-ALD)
In 2023, the team led by Professor Fanny Mochel (AP-HP, Sorbonne University), a Paris brain Institute researcher, showed that daily dose of leriglitazone slow down the progression of myelopathy in patients with X-linked adrenoleukodystrophy, and ...
06.28.2024 Research, science & health
Population de bactéries commensales (en rouge) dans un intestin grêle de souris. Crédit : University of Chicago
The composition of the gut microbiota could influence decision-making
The way we make decisions in a social context can be explained by psychological, social, and political factors. But what if other forces were at work? Hilke Plassmann and her colleagues from the Paris Brain Institute and the University of Bonn show ...
05.16.2024 Research, science & health
Leucodystrophie
New gene therapy for metachromatic leukodystrophy proves effective in mice
Metachromatic leukodystrophy is a rare genetic disorder that mainly affects young children and results in severe neurological symptoms accompanied by a loss of motor and intellectual capacities. At Paris Brain Institute, Françoise Piguet and her ...
04.22.2024 Research, science & health
See all our news