[Pain assessment in non-communicative patients]. / Mesurer la douleur chez le patient non communicant.

Pain is a subjective experience. Its assessment is based on the subject's direct verbal report. This method of assessment is, however, impossible in patients who cannot communicate their feelings. In this context, indirect measurements such as behavioral observations or physiological measurements are needed. To facilitate the assessment of pain in non-communicative patients, numerous standardized behavioral scales have been developed. The aim of this review is to discuss the main validated pain scales employed in end-stage dementia, newborn and preverbal children, and severely brain damaged patients with a disorder of consciousness such as coma, the vegetative state or the minimally conscious state.

[Behavioural assessment and functional neuro-imaing in vegetative state patients]. / Evaluation comportementale et par neuroimagerie fonctionnelle des patients en état végétatif.

Currently, there remains a high rate of misdiagnosis of the vegetative state. This should incite clinicians to use the most sensitive "coma scales" to detect signs of consciousness in these patients. The gold standard remains the Glasgow Coma Scale (GCS, Teasdale and Jennet, 1974), with the Glasgow Liège Scale (GLS, Born, 1988) adding standardized assessment of brainstem reflexes. New sensible behavioral assessment tools for use in the acute neurocritical care setting include the Full Outline of UnResponsiveness (FOUR, Wijdicks et al., 2005). The Coma Recovery Scale-Revised (CRS-R, Giacino and Kalmar, 2004) specifically tests the diagnostic criteria differentiating vegetative from minimally conscious patients. Detecting signs of consciousness also depends on the employed methodology. We showed that for the assesment of the presence of visual pursuit, using a moving mirror is better suited than using a moving object or person. The clinical diagnosis can be confirmed by cerebral positron emission tomography studies objectively quantifying residual metabolic activity in vegetative and minimally conscious patients. Ongoing studies evaluate the prognostic value of functional magnetic resonance imaging studies in these challenging patient populations.

Neuron-specific enolase as a marker of in vitro neuronal damage. Part I: Assessment of neuron-specific enolase as a quantitative and specific marker of neuronal damage.

Enolase in cerebrospinal fluid is a sensitive marker for many types of neurological injuries including head injury and ischemia. We assessed neuron-specific enolase (NSE) as a quantitative and specific biochemical marker of neuronal damage in an experimental model of kainate neurotoxicity. Rat hippocampal cultures were treated with various concentrations of kainate. NSE release into the culture medium was compared with neuronal death estimated either by direct cell counting or by lactate dehydrogenase (LDH) release, largely used to quantify neuronal injury. A dose-response relationship was observed between kainate concentration and the amount of NSE released (r = -0.69; p < 0.05) as well as a significant correlation between NSE release and neuronal death (r = 0.64; p < 0.05). Likewise, a significant correlation was found between LDH and NSE release (r = 0.85; p < 0.05). The specificity of NSE as an indicator of neuronal death was demonstrated using immunocyto-chemistry labeling and measurement of NSE release by pure astrocyte cultures. We concluded that NSE is a reliable, quantitative, and specific marker of neuronal injury.