[en] Post-comatose disorders of consciousness (DoC) represent persistent neurological conditions with limited therapeutic options and a poor prognosis. Recent works advocate for exploring the effects of psychedelics to enhance brain complexity in DoC and ameliorate their consciousness. We investigated sub-anesthetic concentration of the atypical psychedelic ketamine for treating post-comatose prolonged DoC through a double-blind, placebocontrolled, cross-over trial involving three adult patients. Incremental concentrations of intravenous ketamine and saline were administered, alongside continuous EEG recording and assessments of conscious behaviors and spastic paresis. Brain complexity, measured by Lempel-Ziv Complexity (LZC) and Explainable Consciousness Indicator (ECI), revealed increased LZC during ketamine infusion but no change in ECI. Patients exhibited reduced spastic paresis and increased arousal as time spent with eyes open, but no change in diagnosis. No adverse effects were noted. This study contributes to understanding the relationship between consciousness and brain complexity and suggests a potential therapeutic role for ketamine in DoC.
Disciplines :
Neurology Neurosciences & behavior
Author, co-author :
Cardone, Paolo ; Université de Liège - ULiège > GIGA ; Bâtiment, Liège, Belgium
BONHOMME, Arthur ; Centre Hospitalier Universitaire de Liège - CHU > > Frais communs médecine - Pool assistants ; Bâtiment, Liège, Belgium
Bonhomme, Vincent ; Université de Liège - ULiège > Département des sciences cliniques > Anesthésie et réanimation
Lejeune, Nicolas ; Université de Liège - ULiège > GIGA > GIGA Consciousness - Coma Science Group ; William Lennox Rehabilitation Center, Ottignies, Belgium ; Institute of NeuroScience, UCLouvain, Brussels, Belgium ; Bâtiment, Liège, Belgium
Staquet, Cécile ; Centre Hospitalier Universitaire de Liège - CHU > > Service d'anesthésie - réanimation
DEFRESNE, Aline ; Centre Hospitalier Universitaire de Liège - CHU > > Service d'anesthésie - réanimation
Alnagger, Naji ; Université de Liège - ULiège > GIGA > GIGA Consciousness - Coma Science Group ; Bâtiment, Liège, Belgium
Ezan, Pauline; Psychedelic Society Belgium
Lee, Minji; Department of Biomedical Software Engineering, The Catholic University of Korea, Bucheon, Republic of Korea
Piarulli, Andrea ; Université de Liège - ULiège > GIGA > GIGA Consciousness - Coma Science Group ; Department of Surgical, Medical, Molecular, Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
Goethem, Sebastien; William Lennox Rehabilitation Center, Ottignies, Belgium
Montupil, Javier ; Centre Hospitalier Universitaire de Liège - CHU > > Service d'anesthésie - réanimation
Thibaut, Aurore ; Université de Liège - ULiège > GIGA > GIGA Consciousness - Coma Science Group ; Bâtiment, Liège, Belgium
Martial, Charlotte ✱; Université de Liège - ULiège > GIGA > GIGA Consciousness - Coma Science Group ; Bâtiment, Liège, Belgium
Gosseries, Olivia ✱; Université de Liège - ULiège > GIGA > GIGA Consciousness - Coma Science Group ; Bâtiment, Liège, Belgium
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