Frecuencia relativa de ocurrencia de casos probables de «despertar intraoperatorio¼ (DIO) en pacientes sometidos a anestesia general balanceada en el Hospital Central Militar / Relative frequency of occurrence of probable cases of intraoperative awareness (IA) in patients undergoing general balanced anaesthesia in the Central Military Hospital

Resumen Introducción El despertar intraoperatorio (DIO) es un fenómeno poco frecuente que afecta aproximadamente a 0.1-0.2% de los pacientes sometidos a anestesia general balanceada (AGB). Material y métodos Estudio de tipo observacional, descriptivo y transversal para detectar casos probables de DIO en sujetos que fueron sometidos a AGB en el Hospital Central Militar. El método estadístico fue la frecuencia relativa de ocurrencia. Resultados Se realizó con una muestra de 105 pacientes mediante la aplicación del cuestionario de Brice al paciente en la Unidad de Cuidados Postanestésicos en el postoperatorio inmediato y a las 24 horas tras su procedimiento quirúrgico. En un periodo de estudio de seis meses, se estudiaron 105 individuos que cumplieron con criterios de inclusión para el estudio, 51% (54/105) fueron mujeres y 49% (51/105) hombres. La intervención más común fue la colecistectomía laparoscópica (29%). A todos los individuos incluidos en el estudio (100%; 105/105) se les aplicó el cuestionario de Brice en el postoperatorio inmediato. Se detectaron tres casos probables de DIO, lo que representa el 2.8% del universo de estudio. Conclusiones El cuestionario de Brice fue una herramienta de fácil empleo, barata, viable y libre de impacto clínico organizacional negativo para detectar casos probables de DIO en la institución.

Abstract Introduction Intraoperative awareness (IA) is a rare phenomenon that affects approximately 0.1-0.2% of patients undergoing general anesthesia balanced (GBA). Material and methods Observational, descriptive and transversal study to detect probable cases of IA in subjects who were undergoing GBA in the Central Military Hospital. The statistical method used was the relative frequency of occurrence. Results We included a sample of 105 patients to whom we applied the questionnaire of Brice in the immediate postoperative period and 24 hours after their surgical procedure. In a six-month study period, were studied 105 individuals who met the inclusion criteria for the study, 51% (54/105) were female and 49% (51/105) men. Laparoscopic cholecystectomy (29%) was the most common intervention. We applied the questionnaire of Brice in the immediate postoperative period to all individuals included in the study (100%; 105/105). Three probable cases of IA were detected, representing 2.8% of the universe of study. Conclusions The questionnaire of Brice was a tool that was easy to use, inexpensive, viable, and free of negative clinical organizational impact to detect probable cases of IA in the institution.

Investigation into memory formation according to the level of hypnotic depth using process dissociation

BACKGROUND: Process dissociation procedure has been used to evaluate explicit and implicit memories. Two process-dissociation measurement models are described. METHODS: This prospective study evaluated intraoperative memory formation in Korean patients undergoing elective surgery under general anesthesia and its relation to the depth of hypnotic state. A total of 270 patients enrolled were randomly assigned to three groups based on Bispectral Index (BIS) values in the following ranges: 30 to 40, BIS 40 to 50, and BIS 50 to 60 according to the level of hypnotic depth induced by propofol or sevoflurane during the presentation of wordlists. When the level of hypnotic depth was maintained at the target BIS range, words were played for 15 minutes via headphones to patients. Within 24 hours after the word presentation, memory was assessed using an auditory word stem completion test. The probability of explicit and implicit memory was calculated using original and extended measurement models. Brice interviews were performed within 1 and 24 hours after surgery. RESULTS: A total of 119 patients who did not deviate from the target BIS range were included in the analysis. The 95% confidence interval (CI) of the probability of occurrence of implicit memory evaluated by the original model did not include zero. However, when the extension model was used, 0 was included in the 95% CI. Explicit memory evaluated via Brice interviews did not occur in any group. CONCLUSIONS: When BIS was maintained in the range of 30 to 60 during surgery, no explicit or implicit memory was observed.

BIS Monitoring on Intraoperative Awareness: A Meta-analysis / 华中科技大学学报（医学）（英德文版）

Intraoperative awareness is a very serious complication of general anesthesia.Several studies have evaluated the potential association between bispectral index (BIS) and intraoperative awareness,however,the results obtained were controversial.Therefore,we performed a meta-analysis to further assess the association between the BIS monitoring and the incidence of intraoperative awareness.A comprehensive search was conducted to identify all eligible studies from the online literature databases published prior to Feb.2017.A total of five studies with 17 432 cases and 16 749 controls were included.An odds ratio (OR) and a 95％ confidence interval (CI) were calculated to examine the strength of the association.The results showed that in the overall analysis,the association between the BIS monitoring and the incidence of intraoperative awareness was not significant (OR=0.58,95％ CI=0.22-1.58,P=0.29).A stratified analysis by comparing different anesthesia methods revealed that BIS monitoring group showed a lower incidence of intraoperative awareness in patients with intravenous anesthesia when compared with non-BIS monitoring group (OR=0.20,95％ CI=0.08-0.49,P=0.0004),whereas there was no statistically significant difference in the incidence of intraoperative awareness between BIS and non-BIS monitoring groups in patients with inhalation anesthesia (OR=1.13,95％ CI=0.56-2.26,P=0.73).In conclusion,our meta-analysis showed that BIS monitoring had no appreciable advantage in the reduction of the intraoperative awareness incidence in inhalation anesthesia,while showed a remarkable superiority in intravenous anesthesia.

BIS Monitoring on Intraoperative Awareness: A Meta-analysis / 华中科技大学学报（医学）（英德文版）

Intraoperative awareness is a very serious complication of general anesthesia.Several studies have evaluated the potential association between bispectral index (BIS) and intraoperative awareness,however,the results obtained were controversial.Therefore,we performed a meta-analysis to further assess the association between the BIS monitoring and the incidence of intraoperative awareness.A comprehensive search was conducted to identify all eligible studies from the online literature databases published prior to Feb.2017.A total of five studies with 17 432 cases and 16 749 controls were included.An odds ratio (OR) and a 95％ confidence interval (CI) were calculated to examine the strength of the association.The results showed that in the overall analysis,the association between the BIS monitoring and the incidence of intraoperative awareness was not significant (OR=0.58,95％ CI=0.22-1.58,P=0.29).A stratified analysis by comparing different anesthesia methods revealed that BIS monitoring group showed a lower incidence of intraoperative awareness in patients with intravenous anesthesia when compared with non-BIS monitoring group (OR=0.20,95％ CI=0.08-0.49,P=0.0004),whereas there was no statistically significant difference in the incidence of intraoperative awareness between BIS and non-BIS monitoring groups in patients with inhalation anesthesia (OR=1.13,95％ CI=0.56-2.26,P=0.73).In conclusion,our meta-analysis showed that BIS monitoring had no appreciable advantage in the reduction of the intraoperative awareness incidence in inhalation anesthesia,while showed a remarkable superiority in intravenous anesthesia.

Intraoperative awareness as an example of the influence of cardiac output on anesthetic dosing: case report / Despertar intraoperatorio como ejemplo de la influencia del gasto cardíaco en la dosificación anestésica. Reporte de caso

Abstract A case of intraoperative awareness during ablation of pulmonary veins-one of the most widely used techniques in interventional cardiology-is discussed. An infusion of isoproterenol was administered following the ablation of ectopic foci. A few seconds after the infusion the patient experienced increased heart rate and intraoperative awareness manifested as an abrupt patient movement and bispectral index elevation. This has been described in similar procedures, following the administration of isoproterenol. In our opinion, the isoproterenol infusion caused the increased heart rate and subsequent abrupt rise in cardiac output. As an inversely proportional relationship between the propofol concentrations and cardiac output has been described, we believe that this rise in cardiac output could have favored the decline in the concentrations of propofol, leading to an intraoperative awareness episode.

Resumen Presentamos un caso de despertar intraoperatorio durante la ablación de venas pulmonares, una de las técnicas más empleadas por los cardiólogos intervencionistas. Tras la ablación de focos ectópicos se procede a la infusión de isoproterenol. Segundos después de la infusión se produce un aumento de la frecuencia cardíaca seguido de un despertar intraoperatorio traducido como un movimiento brusco del paciente y un aumento en el índice bi-espectral (BIS). Esto ha sido descrito en procedimientos similares tras la administración de isoproterenol. En nuestra opinión, la infusión de isoproterenol provocó un aumento de la frecuencia cardiaca y secundariamente del gasto cardíaco de forma brusca. Dado que se ha descrito una relación inversamente propocional entre las concentraciones de propofol y el gasto cardíaco, pensamos que este aumento del gasto cardíaco pudo condicionar un descenso de las concentraciones de propofol y esto causar el episodio de despertar intraoperatorio.

Principles of anesthesia for craniotomy in awake patients / Principios de la anestesia para craneotomía en paciente vigil

La realización de una craneotomía con el paciente despierto se está utilizando cada vez más en diversas situaciones, como en neurocirugía funcional sobre la estimulación cerebral para tratar la enfermedad de Parkinson y la cirugía para tratar la epilepsia, así como los procedimientos neuroquirúrgicos destinadas a resección de tumores cerebrales en áreas elocuentes. Los principios anestésicos para realizar la craneotomía despierta tienen el objetivo de realización de una analgesia adecuada,sedación, la estabilidad hemodinámica sistémica y la permeabilidad de la vía aérea con el tipo de procedimiento neuroquirúrgico a realizar. El objetivo de este estudio es revisar los principios que rigen la conducta de la anestesia para la neurocirugía que es necesario para lograr la craneotomía con el paciente despierto.

Craniotomy in awake patients is becoming more widely used in a range of situations, such as functional neurology, brain stimulation for treatment of Parkinson disease, surgery for treating epilepsy, as well as in neurological procedures to resect brain tumors in eloquent area. The main anesthesia regimen for craniotomy in the awake patient is chosen to provide the appropriate analgesia, sedation, systemic hemodynamic stability and airway patency for the type of neurosurgical procedure being carried out. The objective of the present study was to conduct a review of the principles governing anesthesia for neurosurgeries involving craniotomy in awake patients.

Unexpected anesthetic leakage from a damaged O-ring on the Selectatec back bar: A case report

The Selectatec mounting system was devised to provide easy and quick on-site fitting of various vaporizers for the anesthetic machine. However, a quick changing system for the vaporizer can also damage the O-ring due to friction between the vaporizer and the Selectatec back bar. We herein report a case of an unexpected anesthetic gas leakage from a damaged O-ring on the Selectatec back bar, which resulted from exchanging the vaporizers between two operations. In cases using the Datex Ohmeda machine, it is not easy to detect leakages from the vaporizers because of the location of the check valve near to the fresh gas outlet. This complicates the use of the positive pressure leakage test to detect a low pressure system leakage on the Selectatec back bar. We recommend the preanesthetic negative pressure or low-flow leakage test to detect a low pressure leakage when exchanging vaporizers on the Selectatec system.

Uso de monitorizacion cerebral para el despertar intraoperatorio / The use of cerebral monitoring for intraoperative awareness

Introduction: the bispectral index monitoring system (BIS) was introduced in the United States in 1994 and approved by the FDA in 1996 with the objective of measuring the level of consciousness through an algorithm analysis of the electroencephalogram (EEG) during general anesthesia. This novelty allowed both the surgeon and the anesthesiologist to have a more objective perception of anesthesia depth. The algorithm is based on different EEG parameters, including time, frequency, and spectral wave. This provides a non-dimensional number, which varies from zero to 100; with optimal levels being between 40 and 60. Objectives: Perform an analysis of the advantages and limitations of the anesthetic management with the bispectral index monitoring, specifically for the management and prevention of intraoperative awareness. Methodology: A non-systematic review was made from literature available in PubMed between the years 2001 and 2015, using keywords such as "BIS", "bispectral monitoring", "monitoreo cerebral", "despertar intraoperatorio", "recall" and "intraoperative awareness". Results: A total of 2526 articles were found, from which only the ones containing both bispectral monitoring and intraoperative awareness information were taken into consideration. A total of 68 articles were used for this review. Conclusion: BIS guided anesthesia has documented less immediate postoperative complications such as incidence of postoperative nausea/vomit, pain and delirium. It also prevents intraoperative awareness and its complications.

Introducción: El índice de monitoreo biespectral (BIS) fue introducido en Norte América en 1994 y aprobado por la FDA en 1996 con el objetivo de medir el nivel de conciencia realizando un análisis algorítmico del electroencefalograma (EEG) durante la anestesia general. Esta novedad permitió que tanto el cirujano como el anestesiólogo tuvieran una percepción más objetiva de la profundidad anestésica. El algoritmo está basado en diferentes parámetros del EEG, incluyendo tiempo, frecuencia y onda espectral. Esto provee un número no dimensional, que varía desde cero, hasta 100; siendo los niveles óptimos entre 40 y 60. Objetívos: Realizar un análisis de las ventajas y limitaciones del manejo anestésico con el monitor de análisis biespectral, específicamente en el manejo y prevención del despertar intraoperatorio. Metodología: Se realizó una revisión no sistemática de literatura disponible en PubMed entre los años 2001-2015, utilizando palabras clave como "BIS", "bispectral monitoring" "moni-toreo cerebral", "despertar intraoperatorio" "recall" y "intraoperative awareness". Resultados: Se encontraron un total de 2526 artículos, de los cuales solo se tomaron en cuenta aquellos que contenían información de tanto monitoria biespectral como despertar intraoperatorio. Un total de 68 artículos fueron utilizados para esta revisión. Conclusión: En la anestesia guiada por BIS se han documentado menores complicaciones postoperatorias inmediatas como la incidencia de nausea/vómito, dolor y delirium. Además de prevenir el despertar intraoperatorio y sus complicaciones.

Mechanisms underlying brain monitoring during anesthesia: limitations, possible improvements, and perspectives / 대한마취과학회지

Currently, anesthesiologists use clinical parameters to directly measure the depth of anesthesia (DoA). This clinical standard of monitoring is often combined with brain monitoring for better assessment of the hypnotic component of anesthesia. Brain monitoring devices provide indices allowing for an immediate assessment of the impact of anesthetics on consciousness. However, questions remain regarding the mechanisms underpinning these indices of hypnosis. By briefly describing current knowledge of the brain's electrical activity during general anesthesia, as well as the operating principles of DoA monitors, the aim of this work is to simplify our understanding of the mathematical processes that allow for translation of complex patterns of brain electrical activity into dimensionless indices. This is a challenging task because mathematical concepts appear remote from clinical practice. Moreover, most DoA algorithms are proprietary algorithms and the difficulty of exploring the inner workings of mathematical models represents an obstacle to accurate simplification. The limitations of current DoA monitors - and the possibility for improvement - as well as perspectives on brain monitoring derived from recent research on corticocortical connectivity and communication are also discussed.

A comparative study between dexmedetomidine and propofol for maintaining depth of anesthesia in elective craniotomy: a prospective randomized double blind study.

Background: The objective of present study was to assess the efficacy of dexmedetomidine over propofol in maintaining depth of anesthesia in patients undergoing elective craniotomy. Methods: Ninety patients of American Society of Anaesthesiologists (ASA) physical status 1 or 2, of either sex, with Glasgow Coma Score (GCS) 14 or 15, scheduled for elective craniotomy, were allocated in two groups, Group D and Group P. Each group consisted of 45 patients. Anesthesia was induced with propofol and maintained with nitrous oxide in oxygen, atracurium and intermittent fentanyl. Patients in Group D received continuous infusion of dexmedetomidine 0.4 μg/kg/hour which was started after induction and stopped after closure of dura in and patients in Group P received continuous infusion of propofol 100 μg/kg/min in same manner. Heart Rate (HR), mean arterial pressure (MAP), and bispectral index (BIS) were recorded and compared at specific time points which are known to have hemodynamic alterations throughout the intraoperative period. Results: Dexmedetomidine was comparable and even better (after intubation p 0.02, head pin fixation p 0.00, opening of dura p <0.00) than propofol in maintaining depth of anesthesia. It also attenuated HR and MAP at intubation, head pin fixation, skin incision, making of burr hole, opening of dura and at extubation (p 0.00). But Ramsay sedation score of patients after extubation in both groups did not differ significantly (p 0.36). No patient had recall. Conclusions: Dexmedetomidine is comparable with propofol in maintaining depth of anesthesia during elective craniotomy. It can be used as a sole anesthetic agent during craniotomy.

Awareness and recall during general anesthesia / 대한마취과학회지

Anesthesia awareness is defined as both consciousness and recall of surgical events. New research has been conducted out to test this phenomenon. However, testing methods have not proven reliable, including those using devices based on electroencephalographic techniques to detect and prevent intraoperative awareness. The limitations of a standard intraoperative brain monitor reflect our insufficient understanding of consciousness. Moreover, patients who experience an intraoperative awareness can develop serious post-traumatic stress disorders that should not be overlooked. In this review, we introduce the incidence of intraoperative awareness during general anesthesia and discuss the mechanisms of consciousness, as well as risk factors, various monitoring methods, outcome and prevention of intraoperative awareness.

Fatores de risco para o despertar intraoperatório / Risk factor for intraoperative awareness / Factores de riesgo para el despertar intraoperatorio

JUSTIFICATIVA E OBJETIVOS: O despertar intraoperatório, evento adverso na anestesia geral, pode ocorrer em cerca de 20.000 casos por ano, o que em si justifica o estudo dos fatores de risco deste evento. O objetivo deste estudo foi fazer uma revisão sobre o tema com a finalidade de diminuir a incidência do despertar intraoperatório e das sequelas psicológicas decorrentes deste incidente, que podem resultar em síndrome de estresse pós-traumático com repercussões negativas sobre o desempenho social, psíquico e funcional do paciente cirúrgico. CONTEÚ;DO: Foi realizada revisão sobre o despertar intraoperatório, avaliando suas diferentes fases durante anestesia geral, sonhos, vigília, memória explicita e implícita, assim como análise, consequências e prevenção dos principais fatores relacionados ao mesmo. CONCLUSÕES: A diminuição na incidência do despertar durante anestesia está ligada ao melhor desempenho cientifico e técnico do anestesiologista, envolvendo questões como a monitoração, a compreensão sobre os componentes da atividade anestésica, drogas hipnóticas, analgésicas, bloqueadores neuromusculares, controle de reflexos autonômicos e motores, além dos fatores de risco envolvidos neste evento.

BACKGROUND AND OBJECTIVES: The intraoperative awareness is an adverse event in the general anesthesia, and may occur in approximately 20,000 cases per year, which justifies the study of the risk factors for this event. The objective of this study was to review this subject in order to reduce the incidence of intraoperative awareness and psychological sequelae incurring from this incident, which may result in post-traumatic stress disorder with negative repercussions on the surgical patient social, psychic and functional development. CONTENT: It was conducted a review of the intraoperative awareness assessing its different phases during general anesthesia such as dreaming, wakefulness, explicit and implicit memory, as well as the analysis, consequences and prevention of its main related factors. CONCLUSIONS: The reduction of awareness incidence during anesthesia is related to the anesthesiologist improved scientific and technical performance, involving issues such as monitoring, comprehension of the anesthesia activity components, hypnotic and analgesic drugs, neuromuscular blocking agents, autonomic and motor reflex control, in addition to the risk factors involved in this event.

JUSTIFICATIVA Y OBJETIVOS: El despertar intraoperatorio, que es un evento adverso en la anestesia general, puede ocurrir en aproximadamente 20.000 casos por año, justificando, por lo tanto, el estudio de sus factores de riesgo. El objetivo de este estudio, fue hacer una revisión sobre el tema, con la finalidad de disminuir la incidencia del despertar intraoperatorio y de las secuelas psicológicas provenientes de ese incidente que pueden resultar en el síndrome de estrés postraumático con repercusiones negativas sobre el desempeño social, psíquico y funcional del paciente quirúrgico. CONTENIDO: Se hizo una revisión del despertar intraoperatorio evaluando sus diferentes fases durante la anestesia general, como el sueño, la vigilia, la memoria explicita e implícita, y también el análisis, las consecuencias y la prevención de los principales factores relacionados con el despertar. CONCLUSIONES: La reducción en la incidencia del despertar durante la anestesia, está vinculada al mejor desempeño científico y técnico del anestesiólogo, involucrando cuestiones como la monitorización, la comprensión sobre los componentes de la actividad anestésica, fármacos hipnóticos, analgésicos, bloqueantes neuromusculares, control de reflejos autonómicos y motores, además de los factores de riesgo involucrados en este evento.

Avaliação clínica de duas ke0 no mesmo modelo farmacocinético de propofol: estudo da perda e recuperação da consciência / Clinical evaluation of two ke0 in the same pharmacokinetic propofol model: study on loss and recovery of consciousness / Evaluación clínica de dos ke0 en el mismo modelo farmacocinético de propofol: estudio de la pérdida y de la recuperación de la conciencia

JUSTIFICATIVA E OBJETIVOS: A constante de equilíbrio entre o plasma e o sítio efetor (ke0) é utilizada pelos modelos farmacocinéticos para prever a concentração do fármaco em seu local de ação (Ce). Seria interessante que a Ce de propofol fosse semelhante na perda e na recuperação da consciência. O objetivo deste estudo foi avaliar o desempenho clínico de duas diferentes ke0 (rápida = 1,21 min-1 e lenta = 0,26 min-1) com relação à Ce durante a perda e a recuperação da consciência, usando o modelo farmacocinético de Marsh. MÉTODO: Participaram deste estudo 20 voluntários adultos sadios do sexo masculino. Em todos os voluntários, administrou-se propofol em regime de infusão alvo-controlada, modelo farmacocinético de Marsh ke0 rápida e, em outra oportunidade, usou-se o mesmo modelo farmacocinético com a ke0 lenta. Inicialmente, o propofol foi infundido em concentração-alvo plasmática de 3,0µg.mL-1. A perda de consciência e a recuperação de consciência basearam-se na resposta ao estímulo verbal. A Ce foi anotada no momento da perda e da recuperação da consciência. RESULTADOS: Na perda e na recuperação da consciência a Ce pela ke0 rápida foi diferente (3,64 ± 0,78 e 1,47 ± 0,29µg.mL-1, respectivamente, p < 0,0001), enquanto com a ke0 lenta a Ce foi semelhante (2,20 ± 0,70 e 2,13 ± 0,43µg.mL-1, respectivamente, p = 0,5425). CONCLUSÕES: Do ponto de vista clínico, a ke0 lenta (0,26 min-1) incorporada ao modelo farmacocinético de Marsh apresentou melhor desempenho que a ke0 rápida (1,21 min-1), uma vez que a concentração de propofol prevista em seu local de ação na perda e recuperação da consciência foi semelhante.

BACKGROUND AND OBJECTIVE: The constant equilibrium between the plasma and effect site (ke0) is used by pharmacokinetic models to calculate a drug concentration in its site of action (Ce). It would be interesting if Ce of propofol was similar at loss and recovery of consciousness. The objective of this study was to evaluate the clinical performance of two different ke0 (fast = 1.21 min-1, and slow = 0.26 min-1) in relation to Ce during loss and recovery of consciousness using Marsh pharmacokinetic model. METHODS: Twenty healthy adult male volunteers participated in this study. In all volunteers propofol was administered as target-controlled infusion, Marsh pharmacokinetic model for fast ke0 and, at a different time, the same pharmacokinetic model with slow ke0 was used. Initially, propofol was infused with a serum target-controlled infusion of 3.0 µg.mL-1. Loss of consciousness and recovery of consciousness were based on response to verbal stimulus. Ce was recorded at the moment of loss and recovery of consciousness. RESULTS: On loss and recovery of consciousness, the Ce for fast ke0 was different (3.64 ± 0.78 and 1.47 ± 0.29 µg.mL-1, respectively, p < 0.0001), while with slow ke0 the Ce was similar (2.20 ± 0.70 and 2.14 ± 0.43 µg.mL-1, respectively, p = 0.5425). CONCLUSIONS: Clinically, the slow ke0 (0.26 min-1) incorporated in the Marsh pharmacokinetic model showed better performance than the fast ke0 (1.21 min-1), since the calculated concentration of propofol at the effect site on loss and recovery of consciousness was similar.

JUSTIFICATIVA Y OBJETIVOS: La constante de equilibrio entre el plasma y el sitio efector (ke0), se usa por los modelos farmacocinéticos para prever la concentración del fármaco en su región de acción (Ce). Sería interesante que el Ce de propofol fuese similar en la pérdida y en la recuperación de la conciencia. El objetivo de este estudio, fue evaluar el desempeño clínico de dos diferentes ke0 (rápida = 1,21 min-1 y lenta = 0,26 min-1), con relación a la Ce durante la pérdida y la recuperación de la conciencia, usando el modelo farmacocinético de Marsh. MéTODO: Participaron en este estudio, 20 voluntarios adultos sanos del sexo masculino. A todos los voluntarios se les administró propofol en régimen de infusión objeto controlada, modelo farmacocinético de Marsh ke0 rápida y en otro momento, se usó el mismo modelo farmacocinético con a ke0 lenta. Inicialmente, el propofol se infundió en concentración-objeto plasmática de 3,0 µg.mL-1. La pérdida de la conciencia y la recuperación de la conciencia estuvieron basadas en la respuesta al estímulo verbal. La Ce fue anotada en el momento de la pérdida y de la recuperación de la conciencia. RESULTADOS: En la pérdida y en la recuperación de la conciencia, la Ce por la ke0 rápida, fue diferente (3,64 ± 0,78 y 1,47 ± 0,29 µg.mL-1, respectivamente, p < 0,0001), mientras que con la ke0 lenta la Ce fue parecida (2,20 ± 0,70 y 2,13 ± 0,43 µg.mL-1, respectivamente, p = 0,5425). CONCLUSIONES: Desde el punto de vista clínico, la ke0 lenta (0,26 min-1) incorporada al modelo farmacocinético de Marsh, presentó un mejor desempeño que la ke0 rápida (1,21 min-1), pues la concentración de propofol prevista en su región de acción en la pérdida y en la recuperación de la conciencia fue similar.

Uso correto do monitor de consciência / Proper use of the monitor of consciousness

O índice bispectral (BIS) é um parâmetro multifatorial que permite a monitorização da componente hipnótico da anestesia. O BIS provê medidas quantificáveis do efeito de anestésicos no cérebro que correlacionam com a profundidade da anestesia. A monito-rização da profundidade anestésica na indução e manutenção da anestesia geral previne consciência e despertar intraoperatório, permite titular a quantidade de anestésicos adequada para promover a rápida recuperação da anestesia e evitar efeitos adversos da superdosagem dos fármacos. Desde sua introdução, a monitorização com BIS vem se tornando comum na prática anestésica. Esta revisão tem o objetivo de elucidar o papel do BIS na monitorização da hipnose na anestesia geral. Foi realizada revisão sobre o conceito de anestesia geral e monitorização da profundidade anestésica com o uso do BIS, bem como atualizações dos benefícios de seu emprego para a qualidade da anestesia, interpretação dos artefatos e drogas que podem interferir na sua utilização...

The bispectral index (BIS) is a multifactorial parameter that allows monitoring of the hypnotic component of anesthesia. The BIS provides quantitiable measures of the effect of anesthetics in the brain that correia te with the depth of anesthesia. Monitoring anesthetic depth during induction and maintenance of general anesthesia prevents intraoperative awakening and conscience and allows to holder the amount of anesthetic agents appropriate to promote a speedy recovery of anesthesia and avoid adverse effects of an overdose of drugs. Since its introduction, the BIS monitoring is becoming acommonplace in anesthetic practice. This review has the objective of elucidating the role of BIS monitor- ing in hypnosis of general anesthesia. A Literature review was conducted on the concepts of general anesthesia and monitoring of anesthetic depth using the BIS Moreover, recent articles on studies of BIS and its benetits in the quality of general anesthesia as well as the presence of artifacts and drugs that may interfere in its utilization...

The Usefulness of the Bispectral Index during Propofol and Fentanyl Anesthesia for Coronary Bypass Surgery under Cardiopulmonary Bypass / 대한마취과학회지

BACKGROUND: The incidence of intraoperative awareness is known to be high in cardiac surgery using cardiopulmaonary bypass, and there is a tendency to use more anesthetics to maintain anesthesia without recall. We investigated the usefulness of the bispectral index monitor in reducing the amount of anesthetics without intraoperative awareness. METHODS: Forty patients scheduled for elective coronary artery bypass graft surgery under cardiopulmonary bypass were randomly allocated into two groups. In the control group, systemic blood pressure was a main indicator to contol the infusion rate of propofol and fentanyl. Infusion rate of propofol and fentanyl were controlled by the bispectral index in the BIS group. A post- anesthetic interview relating to intraoperative awareness was performed on the second postoperative day by a research assistant. RESULTS: The average flow rate of propofol (control group; 0.137+/-0.012 mg/kg/min, BIS group; 0.110+/-0.003 mg/kg/min, P<0.01) and fentanyl (control group; 6.485+/-0.413mug/kg/h, BIS group; 4.321+/-0.5mug/kg/h, P<0.01) were significantly different between groups. The postoperative extubation time was 6.8+/-1.9 h in the control group and 5.3+/-2.3 h in the BIS group (P<0.05). The average BIS was 43.1+/-5.6. No subjects showed positive results in the intraoperative awareness test. CONCLUSIONS: Intraoperative monitoring of the bispectral index in patients undergoing cardiopulmonary bypass for coronary bypass surgery reduced requirement of anesthetics without intraoperative awareness.