Temblores posanestésicos / Post-anesthetic shivering

Introducción: los temblores posanestésico son causa de una de las mayores insatisfacciones durante el posoperatorio inmediato. Es un fenómeno frecuente, potencialmente perjudicial por aumentar la demanda metabólica de oxígeno. Objetivo: hacer una actualización sobre los temblores Posanestésicos y su profilaxis. Métodos: constituyen una actividad muscular oscilatoria para aumentar la producción de calor. Su etiología es desconocida, aunque se le atribuyen numerosas causas. Su frecuencia oscila entre 6,3 y 66 por ciento. De 5 a 65 por ciento relacionadas con anestesia general y 30 por ciento con anestesia regional. Con anestesia general, la temperatura central disminuye entre 0,5 y 1,5 °C, en la primera hora posterior a la inducción, al igual que en la anestesia regional. Este mecanismo se produce por redistribución del calor del centro a la periferia. Todos los anestésicos, opioides y sedantes disminuyen la vasoconstricción y el control autonómico de la regulación térmica y facilitan la hipotermia. Se presenta con mayor frecuencia en pacientes jóvenes, del sexo masculino, en los cuales se administraron agentes anestésicos halogenados, con tiempo anestésico quirúrgico prolongado. Numerosos artículos señalan, que en las especies homeotérmicas se presenta un sistema termorregulador que coordina la defensa contra la temperatura ambiental, para mantener la temperatura interna en un umbral estrecho. La combinación de agentes inductores anestésicos y exposición al ambiente frío hacen que los pacientes presenten temblores posanestésicos. Su profilaxis está dada por el uso de meperidina, clonidina y tramadol. La ketamina, es una fenciclidina, que produce disociación electrofisiológica entre los sistemas límbico y cortical. Se une a dos dianas moleculares en el encéfalo: las terminaciones dopaminérgicas en el núcleo accumbens y los receptores de N-metil de aspartato. Cuando la ketamina se une a dichos receptores, inhibe la liberación de dopamina. Conclusiones: los temblores Posanestésicos constituyen un efecto adverso de la anestesia que pueden ser evitados. La ketamina, por su mecanismo de acción parece jugar un papel en su profilaxis, pues al bloquear dicho receptor se infiere que es posible que module, en alguna medida, la regulación térmica en varios niveles(AU)

Introduction: post-anesthetic shivering is caused by one of the greatest dissatisfactions during the immediate postoperative period. It is a common event, also potentially damaging because it increases the metabolic demand for oxygen. Objective: To make an update on post-anesthetic shivering and its prophylaxis. Methods: It constitutes an oscillatory muscle activity to increase heat production. Its etiology is unknown, although it is attributed to many causes. Its frequency varies between 6.3 and 66 percent. 5 to 65 percent are related to general anesthesia, and 30 percent to regional anesthesia. Under general anesthesia, the central temperature decreases from 0.5 to 1.5 °C in the first hour after induction, as in regional anesthesia. This mechanism is caused by redistribution of heat from the center to the periphery. All anesthetics, opioids and sedatives decrease vasoconstriction and the autonomic control of thermal regulation, and facilitate hypothermia. It occurs most often in young patients, male, to whom halogenated anesthetic agents are administered with anesthetic prolonged surgical time. Many items indicate that in the homeothermic species a thermoregulator system is present, which coordinates the defense against the environmental temperature to maintain the internal temperature in a narrow threshold. The combination of anesthetic inducing agents and exposure to cold environment make patients present post-anesthetic shivering. Prophylaxis is attained by using meperidine, clonidine and tramadol. Ketamine is a phencyclidine, which produces electrophysiological dissociation between the limbic and cortical systems. It is bound to two molecular targets in the brain: dopaminergic terminals in the accumbens nucleus and the N-methyl aspartate receptor. When ketamine binds to these receptors, it inhibits the release of dopamine. Conclusions: Post-anesthetic shivering constitutes an adverse effect of anesthesia, which can be avoided. Ketamine, for its action mechanism, seem to play a role in prevention, because when such receptor is blocked, it is inferred to module, at some extent, thermal regulation at various levels(AU)

Patients with essential tremor can have manual dexterity and attention deficits with no impairments in other cognitive functions / Pacientes com tremor essencial podem apresentar prejuízo na destreza manual e déficit de atenção sem prejuízo em outras áreas da cognição

ABSTRACT Essential tremor (ET) was long believed to be a monosymptomatic disorder. However, studies have evidenced structural changes and attention is now being focused on non-motor symptoms. The objective of the study is to describe and compare ET patients with control groups according to their cognitive functions, and secondarily, to compare their sociodemographic characteristics and other clinical features. All participants were assessed using the Fahn-Tolosa-Marin Tremor Rating Scale for the severity of tremor; a neuropsychological assessment battery and a screening questionnaire for mood and anxiety symptoms. There were no significant age and gender differences between all groups. As for neuropsychological assessment results, a significant difference was found only in the Pegboard test. We also found a significant negative correlation between a poorer cognitive test results and disease severity and a significant differences regarding depression or anxiety symptoms in patients with ET. The study results suggest that patients with ET have impaired manual dexterity and attention.

RESUMO O tremor essencial (TE) era considerado como um transtorno monossintomático. Contudo estudos tem demonstrado alterações anatômicas despertando o interesse para sintomas não-motores.O objetivo do estudo é descrever e comparar pacientes com grupos controles segundo suas funções cognitivas, e secundariamente, comparar suas características demográficas e outros sintomas clínicos. Todos os participantes foram submetidos à escala de Fahn, Tolosa e Marin para avaliação da intensidade do tremor, a uma bateria neuropsicológica e a um questionário para detecção de transtorno de humor e ansiedade. Não houve diferença significativa na idade e gênero entre todos os grupos. Quanto ao resultado da avaliação neuropsicológica, foi encontrado uma diferença significativa apenas no Test Pegboard. Nós também encontramos uma correlação negativa no desempenho dos testes cognitivos e intensidade do tremor, presença de sintomas depressivos e ansiosos. Os resultados deste trabalho sugerem que pacientes com TE apresentem alteração na destreza manual e na atenção.