[The development of a unit devoted to the study of the autonomous nervous system]. / Desarrollo de una unidad dedicada al estudio del Sistema Nervioso Autónomo.

INTRODUCTION: The noninvasive evaluation of the autonomic nervous system (ANS) has been developed in the last decades. The implementation of an specialized unit requires qualified personnel, adequate equipment, location and support. The purpose of the present review is to summarize some theorical and practical aspects of 11 years experience in an ANS Section within a Neurophysiology Department. DEVELOPMENT: During this time we have examined 4,082 patients, using the basic reflex screen in 58% of them with a mean of 100 minutes and 159 Euros per patient. When other types of tests were applied, the time consumed oscillated between 75 and 300 minutes. The patients age ranged from 1 to 91 years, 8% of children among them. From 4,082 patients, the screen was conclusive with some condition related to ANS in 34% of them. The most frequent cause of ANS evaluation was the existence of dizziness, loss of consciousness of unknown origin or syncopal episodes (72%). When patients had at least one spell, sincopal or not, the evaluation was positive in 43%. Patients came from Neurology (67%), Cardiology (8%), Otorhinolaryngology (8%), Endocrinology (7%), and other Departments (10%). CONCLUSION: The different disciplines dealing with autonomic functions promote the diverse origin of autonomic evaluation demand. We suggest the convenience of making an accurate estimation of tests, time and cost per patient, to achieve the best unit management.

Desarrollo de una unidad dedicada al estudio del sistema nervioso autónomo / The development of a unit devoted to the study of the autonomous nervous system

Introducción. Las técnicas de estudio del sistema nervioso autónomo (SNA) por métodos no invasivos se han desarrollado a lo largo de las últimas décadas. La puesta en marcha de una unidad específica requiere recursos humanos cualificados, infraestructura y equipamiento. El objetivo del presente trabajo es revisar aspectos teóricos y prácticos sobre la experiencia de 11 años de funcionamiento de una sección dedicada al estudio del SNA, implantada en un Servicio de Neurofisiología Clínica. Desarrollo. Se han atendido 4.082 pacientes a los que, con mayor frecuencia, se aplicó el estudio básico SNA (58 por ciento), en el que se invierte una media de 100 minutos, con un coste por proceso de 159 EUR. Cuando se utilizaron otras pruebas, el tiempo osciló entre 75 y 300 minutos. La edad de los pacientes es de 1-91 años, con un 8 por ciento de pacientes pediátricos. El estudio SNA resultó patológico en el 34 por ciento de los casos. El motivo de consulta más frecuente fue el relacionado con mareos y pérdida de conciencia de origen indeterminado o con clínica sincopal (72 por ciento). De los pacientes que habían sufrido al menos una pérdida de conciencia, sincopal o no, el estudio SNA resultó positivo en el 43 por ciento de los casos. Los pacientes se remitieron desde Neurología (67 por ciento), Cardiología (8 por ciento), Otorrinolaringología (8 por ciento), Endocrinología (7 por ciento) y otros (10 por ciento). Conclusiones. Las diferentes disciplinas involucradas con las funciones autonómicas son la causa de la diversidad de procedencia de las peticiones de estudio. Señalamos la conveniencia de llevar a cabo una imputación individualizada de pruebas, tiempo y coste por paciente (AU)

Introduction. The noninvasive evaluation of the autonomic nervous system (ANS) has been developed in the last decades. The implementation of an specialized unit requires qualified personnel, adequate equipment, location and support. The purpose of the present review is to summarize some theorical and practical aspects of 11 years experience in an ANS Section within a Neurophysiology Department. Development. During this time we have examined 4,082 patients, using the basic reflex screen in 58% of them with a mean of 100 minutes and 159 Euros per patient. When other types of tests were applied, the time consumed oscillated between 75 and 300 minutes. The patients age ranged from 1 to 91 years, 8% of children among them. From 4,082 patients, the screen was conclusive with some condition related to ANS in 34% of them. The most frequent cause of ANS evaluation was the existence of dizziness, loss of consciousness of unknown origin or syncopal episodes (72%). When patients had at least one spell, sincopal or not, the evaluation was positive in 43%. Patients came from Neurology (67%), Cardiology (8%), Otorhinolaryngology (8%), Endocrinology (7%), and other Departments (10%). Conclusion. The different disciplines dealing with autonomic functions promote the diverse origin of autonomic evaluation demand. We suggest the convenience of making an accurate estimation of tests, time and cost per patient, to achieve the best unit management (AU)

[Orthostatic postural tachycardia: study of 8 patients]. / Taquicardia postural ortostática: estudio de ocho pacientes.

The occurrence of syncopal episodes is a very frequent event. In the absence of a structural systemic or cardiac disease, syncope is resulting of an anomalous cardiovascular response neurally mediated by the autonomic nervous system. It is the final common manifestation of different abnormal mechanisms and is frequently precipitated by orthostatism. Orthostatic intolerance syndrome refers to the development of symptoms during the upright posture that disappear in supine position. Tachycardia may be one of the clinical features of the syndrome. During orthostatic stress a hyperadrenergic response, with maintained increment of heart rate and associated symptoms, is developed. Changes in blood pressure may be diverse and in some cases hypotension and syncope occurs. Eight patients with symptoms of orthostatic intolerance who underwent autonomic evaluation and were diagnosed from postural tachycardia are presented. In all the cases an abnormal increment of heart rate during tilting was found and it was associated to hyperadrenergic symptoms. Evidence of restricted sympathetic impairment was observed in six cases with distal reduction of sudomotor function and abnormal adrenergic response during Valsalva manoeuvre. Symptoms disappeared or mostly subsided with pharmacological (amitriptyline in one case, phenobarbital in another one and non-cardioselective beta-blockers in six patients) and non-pharmacological treatment. In further examinations heart rate and blood pressure were normal.