Coma e outros estados de consciência

Abstract

RESUMO: As alterações do nível de consciência podem variar entre dois extremos, desde uma desorientação têmporo-espacial até um estado de coma profundo. Na prática clínica é extremamente comum o médico se deparar frente a um paciente com alteração do nível de consciência. Em hospitais gerais, estudos indicam o alcoolismo, o traumatismo cranioencefálico e as doenças cardiovasculares como as principais causas de coma (82%). O médico deve saber reconhecer as principais causas de alteração da consciência, seus diagnósticos diferenciais, identifi car o paciente grave e tratar as possíveis alterações emergenciais que possam levar a um dano neurológico secundário. Nesta revisão destacamos os principais pontos no exame neurológico para determinar as diferentes alterações do nível de consciência. DESCRITORES: Coma/diagnóstico. Coma/fi siopatologia. Traumatismos encefálicos/etiologia. Consciência/classifi cação. Diagnóstico diferencial.

Current clinical approach to patients with disorders of consciousness

“…White blood cell count can identify neutrophilic leukocytosis, present in bacterial infections such as meningitis, where it is usually greater than 12,000/mm 3 . In some cases thyroid hormones and serum cortisol may be requested, such as in suspected myxedema coma and Addisonian crisis, respectively.…”

“…Altered levels of conscience can range from temporospatial disorientation to a state of deep coma. 3 Therefore, know how to correctly classify the patient's type of alteration is as important as defining appropriate medical conduct for the clinical symptoms.…”

“…This may be due to a structural injury or metabolic disorder, and information such as previous symptoms, his-tory of recent trauma, personal history, life habits and medications in use are valuable for clinical management. 3 Among the states that are characterized by altered content of consciousness are delirium and dementia. Delirium is characterized by disorientation, attention deficit, a feeling of fear, irritability and changes in the perception of sensory stimuli, such as visual hallucinations.…”

“…3 This usually occurs in patients with bilateral frontal lesions. Akinetic mutism presents symptoms similar to those of abulia but less severe; the patient shows an unwillingness/extreme difficulty to move or speak, with the level and content of consciousness preserved, and eyes following the observer or sound although the patient does not obey commands.…”

“…10 Catatonia is a state in which the individual may remain mute and with a marked decrease of motor activity, usually associated with psychiatric symptoms, but it can also occur due to metabolic disorders or induced by drugs. 3 The patient exhibits bizarre and repetitive behavior, posture disturbances and rigidity.…”