RESUMO
OBJECTIVE: Reflex anoxic cerebral crises are due to depression of nerve function caused by a vagotonic state or vagal hypersensitivity. In this paper we propose to review the physiopathology, clinical features and diagnostic procedures of these crises. DEVELOPMENT: There are three types of reflex anoxic cerebral crises: asphyxiating anoxic crises, ischemic anoxic crises and asphyxiating-ischemic anoxic crises. They are caused by sudden activation of the so-called syncopal reflex. They are characterized by diverse clinical manifestations and may often be mistaken for epileptic crises. They are related to various precipitating factors such as a blow, often to the head, an emotional stimulus or something which upsets or molests, hyperthermia, abdominal pain, headache, physical exertion, prolonged standing-up, exposure to heat, the sight of blood, feeling of fear and other factors. CONCLUSIONS: Important elements for the diagnosis of these crises are the presence of a family history of vagal crises, the presence of precipitating factors, brief duration of the crises (seconds) in most patients, and clinical signs of facial or perioral pallor or cyanosis. The test involving pressure on the eyeball and the tilting table are useful for diagnosis. However, they should be used sensibly.
Assuntos
Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico , Hipóxia Encefálica/diagnóstico , Hipóxia Encefálica/etiologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Humanos , LactenteRESUMO
OBJECTIVE: Reflex anoxic cerebral crises are due to depression of nerve function caused by a vagotonic state or vagal hypersensitivity. In this paper we propose to review the physiopathology, clinical features and diagnostic procedures of these crises. DEVELOPMENT: There are three types of reflex anoxic cerebral crises: asphyxiating anoxic crises, ischemic anoxic crises and asphyxiating-ischemic anoxic crises. They are caused by sudden activation of the so-called syncopal reflex. They are characterized by diverse clinical manifestations and may often be mistaken for epileptic crises. They are related to various precipitating factors such as a blow, often to the head, an emotional stimulus or something which upsets or molests, hyperthermia, abdominal pain, headache, physical exertion, prolonged standing-up, exposure to heat, the sight of blood, feeling of fear and other factors. CONCLUSIONS: Important elements for the diagnosis of these crises are the presence of a family history of vagal crises, the presence of precipitating factors, brief duration of the crises (seconds) in most patients, and clinical signs of facial or perioral pallor or cyanosis. The test involving pressure on the eyeball and the tilting table are useful for diagnosis. However, they should be used sensibly (AU)
Assuntos
Humanos , Pré-Escolar , Criança , Estudo Comparativo , Hipóxia Encefálica/diagnóstico , Hipóxia Encefálica/etiologia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/complicações , Diagnóstico DiferencialRESUMO
INTRODUCTION: Ischemic anoxic cerebral crises are linked to cardio-inhibition in response to vagal hypersensitivity which causes cerebral ischemic. OBJECTIVE: In this paper we proposed to describe the clinical and electrophysiological features seen during the ocular compression test. PATIENTS AND METHODS: We studied 200 children with clinical findings suggesting ischemic anoxic cerebral crises with positive results on ocular compression testing. RESULTS: The ocular compression test provoked signs and symptoms, on average, in between 48.5% and 62.5% of the patients; generalized hypotonia and loss of consciousness were the most frequent signs. We found that the presence of clinical changes depended on the duration of the pause in heartbeat. There was also an association between the duration of the pause in heartbeat and the electroencephalographic findings. CONCLUSIONS: Identification of a state of vagal hypersensitivity is of considerable value in the positive differential diagnosis of cerebral crises in children, and of definite prognostic value.