The impact of EEG in the diagnosis and management of patients with acute impairment of consciousness

Abstract

With the advent of neuroimaging techniques, such as high resolution MRI, PET and SPECT, the importance of the electroencephalogram (EEG) in cerebral disease studies had decreased. However, nowadays, it has received high attention as an important source of information, especially in situations such as unexplained impairment of consciousness [1][2][3] , since it may offer valuable real time information about brain activity, which can be decisive in some life-threatening situations, as convulsive status epilepticus (CSE) and nonconvulsive status epilepticus (NCSE), in which early recognition and ABStrAct Objectives: To assess the frequency of electroencephalogram (EEG) requests in the emergency room (ER) and intensive care unit (ICU) for patients with impairment of consciousness (IC) and its impact in the diagnosis and management. Methods: We followed patients who underwent routine EEG from ER and ICU with IC until discharge or death. Results: During the study, 1679 EEGs were performed, with 149 (8.9%) from ER and ICU. We included 65 patients and 94 EEGs to analyze. Epileptiform activity was present in 42 (44.7%). EEG results changed clinical management in 72.2% of patients. The main reason for EEG requisition was unexplained IC, representing 36.3% of all EEGs analyzed. Eleven (33%) of these had epileptiform activity. Conclusion: EEG is underused in the acute setting. The frequency of epileptiform activity was high in patients with unexplained IC. EEG was helpful in confirming or ruling out the suspected initial diagnosis and changing medical management in 72% of patients.Key words: emergency EEG, impaired of consciousness, emergency room, intensive care unit. reSUMO Objetivo: Avaliar a frequência de exames de eletroencefalograma (EEG) solicitados no pronto-socorro (PS) e na unidade de terapia intensiva (UTI) em pacientes com rebaixamento do nível de consciência, bem como seu impacto no diagnóstico e na conduta. Métodos: Acompanhamos pacientes submetidos ao EEG do PS e da UTI com rebaixamento do nível de consciência até a alta ou óbito. Resultados: Realizamos 1679 EEGs no período de estudo; destes, 149 (8,9%) foram solicitados no PS e na UTI. Incluímos 65 pacientes e 94 EEGs para análise; destes, 42 (44,7%) apresentavam atividade epileptiforme. O EEG mudou a conduta em 72% dos pacientes. A razão principal para solicitação do EEG foi rebaixamento do nível de consciência de origem inexplicável (36,3% dos EEGs). Destes, 33% tinham atividade epileptiforme. Conclusão: Embora o EEG seja pouco usado em condições agudas, a frequência de atividade epileptiforme foi alta nos pacientes com rebaixamento do nível de consciência de origem inexplicável. O EEG foi decisivo para o esclarecimento diagnóstico e implicou mudança da conduta em 72% dos pacientes.Palavras-Chave: EEG de emergência, rebaixamento de consciência, pronto-socorro, unidade de terapia intensiva.immediately treatment may not only prevent death, but also offer better outcomes [1][2][3][4][5][6][7][8] . It might also give important clues in the diagnosis of certain...

Nível Cognitivo De Pacientes Admitidos Em Asilos E Sua Correlação Ocupacional

“…A grande maioria dos estudos encontrados na literatura acerca do EEG os descrevem associados a uma patologia específica (BORGES et al, 2004;KING et al, 1998;MARINO JÚNIOR;CUKIERT;PINHO, 1986) Quanto ao gênero, o estudo em voga apresentou uma proporção de homens para mulheres de 0,81% que se assemelha às taxas já descritas por outros trabalhos. (BORGES et al, 2004;OLEJNICZAK, 2006;RICARDO et al, 2012;SENEVIRATNE et al, 2013) Entretanto, é de se esperar que em estudos que tratem do EEG em uma doença específica, as taxas de frequência de sexo e idade obedeça a epidemiologia associada a esta. Grande parte dos EEGs analisados foram solicitados para investigação de cefaleia e este distúrbio é classicamente descrito como mais comum no sexo feminino, o que corrobora com o maior número de solicitações neste sexo.…”

“…Por fim, contribui-se com a literatura ao demonstrar aquilo que é classicamente descrito, de que alterações em termos de modulação, simetria e sincronia não necessariamente prediz padrões patológicos nos EEG. (OLEJNICZAK, 2006;PRALINE et al, 2007;RICARDO et al, 2012) Haja vista que foram encontradas ondas mal moduladas, assimétricas e assincrônicas em exames sem nenhum grau de disfunção.…”

StatNet Electroencephalogram: A Fast and Reliable Option to Diagnose Nonconvulsive Status Epilepticus in Emergency Setting

“…Critically ill patients with unexplained alteration of mental status in ICU and ED might also suffer this condition. Epileptic activity was recently found in the EEG of almost half of patients with acute impairment of consciousness, 18 and it has been demonstrated that delayed diagnosis and treatment of NCSE may lead to increased neurological complications and mortality 16 19 There is currently no standardized protocol for identifying the patients with suspected NCSE, and no after-hours urgent EEG availability even in some tertiary care centers 20 .…”

How valuable is inpatient electroencephalogram for medical decision‐making?

“…In previous studies, EEGs confirmed diagnosis and altered management in 0-22% of the patients [4,11,14]. Higher yield of abnormal findings and higher rates of contribution to making the diagnosis (42-100%) were reported in the emergent setting, when EEGs were performed for diagnosis of nonconvulsive and subtle status epilepticus, follow-up of convulsive status epilepticus and suspected cerebral death in patients presented to the emergency department or admitted in intensive care units with altered mental states, although low rates of 5% and 10Á7% of status epilepticus confirmation were reported in these patients as well [15][16][17][18][19][20][21].…”