Using smells to help predict recovery in comatose or unresponsive ICU patients
Official title: Consciousness Prognosis Evaluation Using Olfactory Stimulations in Comatose Patients
Run by Centre Hospitalier St Anne · NCT07127224 · Data updated 2026-11-12
This will test whether brief smell challenges and a patient's 'sniff' response can help predict neurological and functional status three months later for adults who remain unresponsive after stopping sedation in the neuro-ICU.
Quick facts
| Study type | Interventional |
|---|---|
| Ages | 18 Years and up |
| Sex | All |
| Enrollment | 96 (estimated) |
| Sponsor | Centre Hospitalier St Anne Academic / other |
| Locations | 1 site (Paris, GHU Psychiatrie Et Neurosciences) |
| Status | Recruiting |
| Started | February 5, 2024 |
| Main results expected | May 5, 2027 |
| Study ends | May 5, 2027 |
| Registry record updated | August 17, 2025 |
| Trial ID | NCT07127224 on ClinicalTrials.gov |
Is this trial a fit for you?
✓Likely a good fit
Adults (≥18) admitted to the neuro-ICU who remain unresponsive with a CRS-R score <16 at 72 hours after sedation withdrawal and are breathing spontaneously, with consent from a legal representative or emergency waiver.
✕Probably not a fit
Patients with brain death, known ENT/olfactory pathway damage, neurodegenerative disease, or other conditions that prevent olfactory perception are unlikely to benefit from this olfactory prognostic test.
A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.
What this trial studies
This is an observational protocol that adds standardized olfactory stimulation to routine neurophysiological evaluation in adult neuro-ICU patients with persistent disorders of consciousness after sedation withdrawal. Investigators will record the presence or absence of a bedside 'sniff' response and compare olfactory-evoked signals with somatosensory and auditory evoked responses. Participants are followed at three months for clinical, neurological, and functional outcomes to determine whether the olfactory response provides additional prognostic information. No experimental treatment is given; the procedure consists of extra sensory testing performed during the hospital stay.
Why it matters
Potential benefit: If successful, this could provide a simple, noninvasive bedside marker to improve early prognostication and help guide clinical decisions for unresponsive ICU patients.
How similar studies have gone: Use of olfactory stimulation for prognostication is relatively novel compared with somatosensory and auditory tests, with some preliminary data suggesting promise but limited definitive evidence to date.
Who can join: the full rules
Show full inclusion / exclusion criteria
Inclusion Criteria: * Admission to neuro-intensive care unit (neuro-ICU) * Age ≥ 18 years * Patients with persistent disorders of consciousness defined by an abnormal CRS-R score (\<16) at 72 hours after sedation withdrawal and spontaneous ventilation * Consent obtained from legal representatives or activation of emergency waiver * Patient covered by or affiliated with a social security system Exclusion Criteria: * Pregnancy * Brain death * Pre-existing ENT or olfactory bulb pathologies that may affect olfactory functions * Acute or chronic peripheral neurological diseases that may alter evoked potentials * Known neurodegenerative diseases (e.g., Parkinson's disease, Alzheimer's disease) * Patients under legal guardianship or protective supervision (safeguard or protection measures)
Where it's running
-
GHU Psychiatrie et Neurosciences
Paris, GHU Psychiatrie Et Neurosciences, France Recruiting
Study contacts
- Study coordinator: Eleonore BOUCHEREAU, MD, PhD
- Email: e.bouchereau@ghu-paris.fr
- Phone: 0145658902
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How to take part
- Review the eligibility criteria above with your treating physician.
- Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
- Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.