[How to quantify the severity of brain injury during intensive care after adult head trauma]

Adequate early assessment of brain damage is essential. Location, extension and severity of structural damage affect brain function and ultimately determine the outcome. The extent of functional impairment, and the morphology of intracranial lesions, require specific treatment, often a combination of medical and surgical interventions. Brain damage usually evolves over time, and repeated assessments are necessary. Clinical evaluation is often biased by concomitant sedation and/or anesthesia, but remains necessary. A revision of the literature is presented. Brain damage is assessed combining clinical and instrumental data. Clinical examination is performed assessing the 3 components of the Glasgow Coma Scale. Spontaneous or stimulated (pain stimulus) eye opening, verbal and motor responses are observed after hemodynamic and respiratory stabilisation. Unfortunately a significant proportion of patients can not be properly examined for several reasons: eye opening can be altered by palpebral and facial injuries, verbal response can be impaired by maxillo-facial injuries or by endotracheal intubation, and motor response remains the most consistent parameter. Sedation, analgesia and myorelaxants, however, can profoundly diminish or abolish the motor response to maximal stimulation, so that examination should be performed after clearance of drugs. Often alcohol or other substances can further impair the neurological performances. Pupils diameter and reactivity to light should be observed, excluding pharmacologic effects (as dilation due to catecholamines) and direct ocular or orbital damage. The CT scan is necessary for disclosing surgical masses and for identifying the extent of diffuse damage and the location of focal lesions. These data should be combined with additional functional exploration, as provided by cerebral extraction of oxygen and electrophysiologic data. Early estimation of cerebral damage is complex and prone to mistakes. Accurate, repeated evaluations, based on the combination of clinical observation and imaging, are necessary.