Fernando Squeff Nora

Anestesia venosa total em regime de infusão alvo-controlada: uma análise evolutiva

BACKGROUND AND OBJECTIVES Total intravenous anesthesia (TIVA) has seen several developments since it was first used. Since the synthesis of the first intravenous anesthetics, with the introduction of barbiturates (1921) and thiopental (1934), TIVA has evolved until the development of TIVA with target-controlled infusion pumps (TCI). The first pharmacokinetic model for the use of TCI was described by Schwilden in 1981. From that moment on, it was demonstrated that it is possible to maintain the desired plasma concentration of a drug using an infusion pump managed by a computer. CONTENTS The objective of this report was to describe the theoretical bases of TCI, propose the development of a common TCI vocabulary, which has not been done in Brazil and make a critical analysis of the current aspects of TCI in the world and in Brazil. CONCLUSIONS The advent of new infusion pumps with pharmacokinetic models of remifentanil, sufentanil and propofol opens a new chapter in TIVA and aligns Brazil with the world tendency in TCI. Those systems will allow TCI of hypnotics and opioids concomitantly. However, the most important conclusion refers to the economy, since drugs used in those pumps will not be restricted to only one drug company, similar to what happened with propofol. Nowadays, TCI devices for the use of propofol and opioids, which accept any pharmaceutical presentation, with the advantage of changing the concentration of the drug in the syringe according to the dilution desired are available.BACKGROUND AND DOBJECTIVES: Total intravenous anesthesia (TIVA) has seen several developments since it was first used. Since the synthesis of the first intravenous anesthetics, with the introduction of barbiturates (1921) and thiopental (1934), TIVA has evolved until the development of TIVA with target-controlled infusion pumps (TCI). The first pharmacokinetic model for the use of TCI was described by Schwilden in 1981. From that moment on, it was demonstrated that it is possible to maintain the desired plasma concentration of a drug using an infusion pump managed by a computer. CONTENTS: The objective of this report was to describe the theoretical bases of TCI, propose the development of a common TCI vocabulary, which has not been done in Brazil and make a critical analysis of the current aspects of TCI in the world and in Brazil. CONCLUSIONS: The advent of new infusion pumps with pharmacokinetic models of remifentanil, sufentanil and propofol opens a new chapter in TIVA and aligns Brazil with the world tendency in TCI. Those systems will allow TCI of hypnotics and opioids concomitantly. However, the most important conclusion refers to the economy, since drugs used in those pumps will not be restricted to only one drug company, similar to what happened with propofol. Nowadays, TCI devices for the use of propofol and opioids, which accept any pharmaceutical presentation, with the advantage of changing the concentration of the drug in the syringe according to the dilution desired are available.

Total intravenous anesthesia as a target-controlled infusion: an evolutive analysis

BACKGROUND AND OBJECTIVES Total intravenous anesthesia (TIVA) has seen several developments since it was first used. Since the synthesis of the first intravenous anesthetics, with the introduction of barbiturates (1921) and thiopental (1934), TIVA has evolved until the development of TIVA with target-controlled infusion pumps (TCI). The first pharmacokinetic model for the use of TCI was described by Schwilden in 1981. From that moment on, it was demonstrated that it is possible to maintain the desired plasma concentration of a drug using an infusion pump managed by a computer. CONTENTS The objective of this report was to describe the theoretical bases of TCI, propose the development of a common TCI vocabulary, which has not been done in Brazil and make a critical analysis of the current aspects of TCI in the world and in Brazil. CONCLUSIONS The advent of new infusion pumps with pharmacokinetic models of remifentanil, sufentanil and propofol opens a new chapter in TIVA and aligns Brazil with the world tendency in TCI. Those systems will allow TCI of hypnotics and opioids concomitantly. However, the most important conclusion refers to the economy, since drugs used in those pumps will not be restricted to only one drug company, similar to what happened with propofol. Nowadays, TCI devices for the use of propofol and opioids, which accept any pharmaceutical presentation, with the advantage of changing the concentration of the drug in the syringe according to the dilution desired are available.BACKGROUND AND DOBJECTIVES: Total intravenous anesthesia (TIVA) has seen several developments since it was first used. Since the synthesis of the first intravenous anesthetics, with the introduction of barbiturates (1921) and thiopental (1934), TIVA has evolved until the development of TIVA with target-controlled infusion pumps (TCI). The first pharmacokinetic model for the use of TCI was described by Schwilden in 1981. From that moment on, it was demonstrated that it is possible to maintain the desired plasma concentration of a drug using an infusion pump managed by a computer. CONTENTS: The objective of this report was to describe the theoretical bases of TCI, propose the development of a common TCI vocabulary, which has not been done in Brazil and make a critical analysis of the current aspects of TCI in the world and in Brazil. CONCLUSIONS: The advent of new infusion pumps with pharmacokinetic models of remifentanil, sufentanil and propofol opens a new chapter in TIVA and aligns Brazil with the world tendency in TCI. Those systems will allow TCI of hypnotics and opioids concomitantly. However, the most important conclusion refers to the economy, since drugs used in those pumps will not be restricted to only one drug company, similar to what happened with propofol. Nowadays, TCI devices for the use of propofol and opioids, which accept any pharmaceutical presentation, with the advantage of changing the concentration of the drug in the syringe according to the dilution desired are available.

Atitudes atuais de anestesiologistas e médicos em especialização com relação à anestesia venosa total

BACKGROUND AND OBJECTIVES In the past, time, cost, information, training, and the evaluation of the plane of anesthesia limited the acceptance of total intravenous anesthesia (TIVA). The objective of this study was to determine the attitude of anesthesiologists and other anesthesiology residents regarding total intravenous anesthesia. METHODS A questionnaire was sent to 150 anesthesiologists and 102 residents. The concordance (C) and disaccord (D) of each item were compared by z tests (consensus if p < 0.05). RESULTS There were 98 responses. The data represent the number of answers for each category. The majority of the participants agreed that the quality of the awakening stimulates the use of the TIVA (C/D = 86/8; p < 0.05); that the future depends on the development of drugs with a fast onset of action and immediate recovery (C/D = 88/5; p < 0.05); that they would like to use TIVA more often (C/D = 72/21; p < 0.05); and to have more information about TIVA (C/D = 77/14; p < 0.05). There was no agreement about the level of knowledge necessary to administer this technique when compared to inhalational anesthesia (C/D = 48/47); the majority of those who answered the questionnaire did not express any concerns with intra-surgical consciousness (C/D = 20/77; p < 0.05) but agreed that de availability of consciousness monitors would increase the use of TIVA (C/D = 64/25; p < 0.05). There was no consensus whether the need for infusion pumps (C/D = 52/40) and costs (CD = 52/39) limit its use. CONCLUSIONS The attitude regarding TIVA was predominantly positive. There was no consensus on the influence of the level of knowledge, of the infusion pumps, and of the costs on the use of TIVA.JUSTIFICATIVA Y OBJETIVOS: Antiguamente, tiempo, costes, informaciones, capacitacion y evaluacion de la profundidad de la anestesia limitaban la aceptacion de la anestesia venosa total (TIVA). El objetivo de este estudio fue el de determinar las actitudes de anestesiologos y medicos en especializacion con relacion a la anestesia venosa total. METODO: Un cuestionario fue enviado a 150 anestesiologos y 102 residentes. La concordancia (C) y discordancia (D) en cada item se compararon por pruebas z (consenso, si p < 0,05). RESULTADOS: Hubo 98 respuestas. Los datos representaron numeros de respuestas por categoria. La mayoria de los participantes concordo en que la calidad del despertar estimula el uso de TIVA (C/D = 86/8; p < 0,05); que el futuro reside en el desarrollo de farmacos con un rapido inicio de accion y una rapida recuperacion (C/D = 88/5; p < 0,05); que les gustarian utilizar TIVA con mas frecuencia (C/D = 72/21; p < 0,05) y saber mas sobre TIVA (C/D = 77/14; p < 0,05). No hubo consenso sobre el nivel de conocimiento para realizarla, comparada con la anestesia de inhalacion (C/D = 48/47); la mayoria no expreso preocupacion con la conciencia intraoperatoria (C/D = 20/77; p < 0,05), pero concordo en que la disponibilidad de monitores de conciencia, aumentaria la utilizacion de TIVA (C/D = 64/25; p < 0,05). No hubo consenso sobre la necesidad de bombas de infusion (C/D = 52/40) y costes (C/D = 52/39) limitan su uso. CONCLUSIONES: Las actitudes con relacion a la TIVA fueron predominantemente positivas. No hubo consenso sobre las contribuciones del nivel de conocimiento, de los dispositivos de infusion y de los costes para el uso de TIVA.

Remifentanil: o regime de infusão faz diferença na prevenção das respostas circulatórias à intubação traqueal?

JUSTIFICATIVA Y OBJETIVOS: Los opioides en dosis elevadas disminuyen la respuesta circulatoria a la intubacion traqueal. Sin embargo, el lento perfil de recuperacion de los opioides tradicionales puede limitar la utilizacion en altas dosis. El remifentanil posee tiempo de inicio y de termino de accion rapidos y previsibles, lo que lo diferencia de los demas. El objetivo primario de este estudio fue verificar la hipotesis de que no hay necesidad de iniciar la administracion de remifentanil antes de la induccion con el propofol. METODO: Fueron evaluados 30 pacientes, divididos en dos grupos, que recibieron anestesia general intravenosa total. En el Grupo 1, la infusion de remifentanil (0,3 µg.kg-1.min-1) se inicio dos minutos antes de la induccion y, en el Grupo 2, conjuntamente con la induccion. Se evaluaron las presiones arteriales sistolica, diastolica y promedio (PAS, PAD, PAM), frecuencia cardiaca (FC), concentraciones en el local efector de propofol (CEF-prop) y de remifentanil (CEF-remi) en tres momentos: basal (M0); despues de la perdida del contacto verbal (M1); y despues de la intubacion traqueal (M2). RESULTADOS: Las presiones arteriales presentaron reducciones significativas en los dos grupos: M1 y M2. La CEF-remi fue mayor en el Grupo 1, en M1 y mayor en el Grupo 2, en M2 (p < 0,05). Hubo correlaciones estadisticas significativas entre el indice de sobrecarga vascular (ISV) y la variacion de tension sistolica despues de la perdida del contacto verbal en el Grupo 1 (r = -0,80; p < 0,01) y despues de la intubacion traqueal en el Grupo 2 (r = -0,60; p < 0,01). CONCLUSIONES: El remifentanil administrado dos minutos antes de la induccion con el propofol no causo proteccion cardiovascular adicional a las maniobras de intubacion traqueal. Eso nos sugiere que el inicio de la infusion de remifentanil dos minutos antes de la induccion sea innecesario.BACKGROUND AND OBJECTIVES High doses of opioids decrease the hemodynamic response to tracheal intubation. However, the slow recovery profile of traditional opioids may limit the use of high doses. Remifentanil has a fast time of onset and is short acting, which differentiates it from the other drugs in this class. The primary objective of this study was to verify the hypothesis that there is no need to initiate the administration of remifentanil before the induction with propofol. METHODS Thirty patients, divided in two groups, who received total intravenous anesthesia, were evaluated. In Group 1, the infusion of remifentanil (0.3 microg.kg-1.min-1) was initiated two minutes before induction, and in Group 2, at the same time of the induction. Systolic, diastolic, and mean arterial blood pressure (SBP, DBP, MAP), heart rate (HR), concentration of propofol (CEF-prop) and remifentanil (CEF-remi) in the effector area in three moments: baseline (M0), after losing verbal contact (M1), and after tracheal intubation (M2) were evaluated. RESULTS There were significant reductions in blood pressure in both groups at M1 and M2. CEF-remi was greater in Group 1, at M1, and greater in Group 2, at M2 (p < 0.05). There was a significant statistical correlation between the vascular overload index (VOI) and the variation of the systolic pressure after the loss of verbal contact in Group 1 (r = -0.80; p < 0.01) and in Group 2 after tracheal intubation (r = -0.60; p < 0.01). CONCLUSIONS Remifentanil administered two minutes before induction with propofol did not offer additional cardiovascular protection to tracheal intubation. This suggests that it is not necessary to start the infusion of remifentanil two minutes before anesthetic induction.

Current attitude of anesthesiologists and anesthesiology residents regarding total intravenous anesthesia

BACKGROUND AND OBJECTIVES In the past, time, cost, information, training, and the evaluation of the plane of anesthesia limited the acceptance of total intravenous anesthesia (TIVA). The objective of this study was to determine the attitude of anesthesiologists and other anesthesiology residents regarding total intravenous anesthesia. METHODS A questionnaire was sent to 150 anesthesiologists and 102 residents. The concordance (C) and disaccord (D) of each item were compared by z tests (consensus if p < 0.05). RESULTS There were 98 responses. The data represent the number of answers for each category. The majority of the participants agreed that the quality of the awakening stimulates the use of the TIVA (C/D = 86/8; p < 0.05); that the future depends on the development of drugs with a fast onset of action and immediate recovery (C/D = 88/5; p < 0.05); that they would like to use TIVA more often (C/D = 72/21; p < 0.05); and to have more information about TIVA (C/D = 77/14; p < 0.05). There was no agreement about the level of knowledge necessary to administer this technique when compared to inhalational anesthesia (C/D = 48/47); the majority of those who answered the questionnaire did not express any concerns with intra-surgical consciousness (C/D = 20/77; p < 0.05) but agreed that de availability of consciousness monitors would increase the use of TIVA (C/D = 64/25; p < 0.05). There was no consensus whether the need for infusion pumps (C/D = 52/40) and costs (CD = 52/39) limit its use. CONCLUSIONS The attitude regarding TIVA was predominantly positive. There was no consensus on the influence of the level of knowledge, of the infusion pumps, and of the costs on the use of TIVA.JUSTIFICATIVA Y OBJETIVOS: Antiguamente, tiempo, costes, informaciones, capacitacion y evaluacion de la profundidad de la anestesia limitaban la aceptacion de la anestesia venosa total (TIVA). El objetivo de este estudio fue el de determinar las actitudes de anestesiologos y medicos en especializacion con relacion a la anestesia venosa total. METODO: Un cuestionario fue enviado a 150 anestesiologos y 102 residentes. La concordancia (C) y discordancia (D) en cada item se compararon por pruebas z (consenso, si p < 0,05). RESULTADOS: Hubo 98 respuestas. Los datos representaron numeros de respuestas por categoria. La mayoria de los participantes concordo en que la calidad del despertar estimula el uso de TIVA (C/D = 86/8; p < 0,05); que el futuro reside en el desarrollo de farmacos con un rapido inicio de accion y una rapida recuperacion (C/D = 88/5; p < 0,05); que les gustarian utilizar TIVA con mas frecuencia (C/D = 72/21; p < 0,05) y saber mas sobre TIVA (C/D = 77/14; p < 0,05). No hubo consenso sobre el nivel de conocimiento para realizarla, comparada con la anestesia de inhalacion (C/D = 48/47); la mayoria no expreso preocupacion con la conciencia intraoperatoria (C/D = 20/77; p < 0,05), pero concordo en que la disponibilidad de monitores de conciencia, aumentaria la utilizacion de TIVA (C/D = 64/25; p < 0,05). No hubo consenso sobre la necesidad de bombas de infusion (C/D = 52/40) y costes (C/D = 52/39) limitan su uso. CONCLUSIONES: Las actitudes con relacion a la TIVA fueron predominantemente positivas. No hubo consenso sobre las contribuciones del nivel de conocimiento, de los dispositivos de infusion y de los costes para el uso de TIVA.

Influence of Total Intravenous Anesthesia, Entropy and Laparoscopy on Oxidative Stress

BACKGROUND AND OBJECTIVES Recent studies have correlated postoperative mortality with anesthetic mortality, especially with the depth of anesthesia and systolic blood pressure (SBP). The aim of this study is to evaluate the effects of the depth of total intravenous anesthesia (TIVA) using remifentanil and propofol, performed with monitoring of response entropy (RE) on blood concentrations of oxidative stress markers (TBARS and glutathione) during laparoscopic operations. METHOD Twenty adult patients, ASA I, BMI 20-26 kg.m(-2), aged 20 to 40 years, were randomly distributed into two groups: Group I underwent anesthetic-surgical procedure with RE maintained between 45 and 59, and Group II underwent anesthetic-surgical procedure with RE between 30 and 44. In both groups, the remifentanil and propofol infusion was controlled by the effector site (Es), adjusted to maintain RE desired values (Groups I and II) and always assessing the suppression rate (SR). Patients were evaluated in six periods: M1 (immediately before anesthesia), M2 (before tracheal intubation [TI]), M3 (5-minutes after TI), M4 (immediately before pneumoperitoneum [PPT]), M5 (1-minute after PPT), and M6 (1-hour after the operation). The following parameters were assessed at all times: SBP, DBP, HR, RE, SR, TBARS, and glutathione. RESULTS We found increases in TBARS and glutathione in M5, both in Group I and Group II (p<0.05), with higher values in Group II, and SR in three patients in Group II, immediately after PPT. CONCLUSIONS Increased markers in Group I (M5) suggests an increase in anaerobic metabolism (AM) in the splanchnic circulation while the highest values seen in Group II (GII > GI in M5, p<0.05%) suggest interference of another factor (deep anesthesia) responsible for the increase in AM, probably as a result of increased autonomic nervous system depression and minor splanchnic self-regulation.

Target-controlled total intravenous anesthesia associated with femoral nerve block for arthroscopic knee meniscectomy

JUSTIFICATIVA Y OBJETIVOS: El aumento de la popularidad de tecnicas operatorias minimamente invasivas, redujo los tiempos de recuperacion de procedimientos que anteriormente se asociaban a un extenso periodo de ingreso. Este trabajo presenta una tecnica de anestesia general venosa total con propofol y remifentanil combinada con el bloqueo del nervio femoral por acceso perivascular inguinal. METODO: Se incluyeron 90 pacientes sometidos a artroscopia de la rodilla para meniscectomias. La induccion anestesica se hizo con propofol en infusion objeto controlada (IAC) (objetivo = 4 µg.mL-1) y con remifentanil en IAC (objeto = 3 ng.mL-1). Las alteraciones de las concentraciones de propofol y remifentanil eran realizadas de acuerdo con la electroencefalografia bispectral (BIS) y la presion arterial promedio (PAM). La ventilacion era mecanica y controlada a volumen; la via aerea se mantenia con mascara laringea. Los valores de las concentraciones en el local efector de propofol y remifentanil se obtenian a traves de los modelos farmacocineticos de los farmacos, insertados en las bombas de IAC y correspondieron a las concentraciones predictibles. El local efector se refiere al local de accion de los farmacos. El tiempo de alta comprendio el espacio de tiempo entre la llegada del paciente a la sala de recuperacion hasta el momento del alta. RESULTADOS: Las concentraciones promedios en el local efector (ng.mL-1), maximas y minimas de remifentanil fueron de 3,5 y 2,4 respectivamente. Las concentraciones promedios en el local efector (µg.mL-1), maximas y minimas de propofol, fueron respectivamente de 3,1 y 2,6. El caudal promedio de infusion de propofol y de remifentanil fue de 8,54 mg.kg-1.h-1 y de 0,12 µg.kg-1.min-1, respectivamente. Los tiempos de alta fueron como promedio de 180 min. CONCLUSIONES: Todos los pacientes se mantuvieron dentro de los parametros establecidos.BACKGROUND AND OBJECTIVES The increased popularity of minimally invasive surgical techniques reduced recovery time of procedures that were usually associated with prolonged hospitalization. This study reports the technique of total intravenous anesthesia with propofol and remifentanil associated with femoral nerve block using the inguinal perivascular approach. METHODS Ninety patients undergoing knee arthroscopy for meniscectomy were included in this study. Target-controlled infusion (TCI) of propofol (target = 4 microg.mL(-1)) and remifentanil (target = 3 ng.mL(-1)) was used for induction of anesthesia. The concentrations of propofol and remifentanil were changed according to the bispectral index (BIS) and mean arterial pressure (MAP). Volume-controlled mechanical ventilation with a laryngeal mask was used. The concentrations of propofol and remifentanil at the effector site, corresponding to the predictive concentrations, were obtained using the pharmacokinetic models of the drugs inserted in the TCI pumps. Time for hospital discharge encompassed the period between the moment the patient arrived at the recovery room and hospital discharge. RESULTS Maximal and minimal mean concentrations at the effector site (ng.mL(-1)) of remifentanil were 3.5 and 2.4, respectively. Maximal and minimal mean concentrations of propofol at the effector site (microg.mL(-1)) were 3.1 and 2.6, respectively. The mean flow of infusion of propofol and remifentanil was 8.54 mg.kg(-1).h(-1) and 0.12 microg.kg(-1).min(-1), respectively. Mean hospital discharge time was 180 min. CONCLUSIONS All patients were maintained within established parameters.

Anestesia venosa total com infusão alvo-controlada de remifentanil e propofol para ablação de fibrilação atrial

CASE REPORT: This is a 49-year old female weighing 73 kg, 155 cm, and ASA II due to hypertension. The patient was monitored with a 12-lead ECG, pulse oximetry, heart rate, bispectral electroencephalography for BIS measurement, suppression rate (SR), and SEF95, and mean arterial pressure (MAP). Intravenous targetcontrolled infusion (TCI) of propofol with a target of 4 μg.mL-1, intravenous TCI of remifentanil with a target of 3 ng.mL-1, and intravenous bolus of rocuronium 0.2 mg.kg-1 were used for induction of anesthesia. The pharmacokinetic model of propofol described by Marsh was used and incorporated into the propofol PFS pump®. The pharmacokinetic model of remifentanil described by Minto was incorporated into the Alaris PK® infusion pump. Local effector, or biophase, concentrations corresponded to the information obtained from the infusion pumps and represented predictive measurements of the concentrations of both drugs on their sites of action. The concentrations of propofol and remifentanil were regulated according to BIS and MAP, respectively.

Total intravenous anesthesia with target-controlled infusion of remifetanil and propofol for ablation of atrial fibrillation

Summary Background and objectives Although ablation of atrial fibrillation (AF) is common in other centers, among us it is a new procedure. The choice of anesthesia, monitors, and anesthesiologic care for this procedure performed outside the surgical center has not been described. The objective of this report was to describe an anesthesia technique for ablation of AF. Case report This is a 49-year old female weighing 73 kg, 155 cm, and ASA II due to hypertension. The patient was monitored with a 12-lead ECG, pulse oximetry, heart rate, bispectral electroencephalography for BIS measurement, suppression rate (SR), and SEF95, and mean arterial pressure (MAP). Intravenous targetcontrolled infusion (TCI) of propofol with a target of 4 μg.mL -1 , intravenous TCI of remifentanil with a target of 3 ng.mL -1 , and intravenous bolus of rocuronium 0.2 mg.kg -1 were used for induction of anesthesia. The pharmacokinetic model of propofol described by Marsh was used and incorporated into the propofol PFS pump ® . The pharmacokinetic model of remifentanil described by Minto was incorporated into the Alaris PK ® infusion pump. Local effector, or biophase, concentrations corresponded to the information obtained from the infusion pumps and represented predictive measurements of the concentrations of both drugs on their sites of action. The concentrations of propofol and remifentanil were regulated according to BIS and MAP, respectively. Conclusions Total intravenous anesthesia for ablation of AF can be a safe option considering the lack of electrophysiological changes in accessory pathways. The literature on this subject is scarce and new publications could justify, or not, this type of anesthesia during ablation of AF.

Anestesia venosa total em infusão alvo-controlada associada a bloqueio do nervo femoral para meniscectomia do joelho por acesso artroscópico

JUSTIFICATIVA Y OBJETIVOS: El aumento de la popularidad de tecnicas operatorias minimamente invasivas, redujo los tiempos de recuperacion de procedimientos que anteriormente se asociaban a un extenso periodo de ingreso. Este trabajo presenta una tecnica de anestesia general venosa total con propofol y remifentanil combinada con el bloqueo del nervio femoral por acceso perivascular inguinal. METODO: Se incluyeron 90 pacientes sometidos a artroscopia de la rodilla para meniscectomias. La induccion anestesica se hizo con propofol en infusion objeto controlada (IAC) (objetivo = 4 µg.mL-1) y con remifentanil en IAC (objeto = 3 ng.mL-1). Las alteraciones de las concentraciones de propofol y remifentanil eran realizadas de acuerdo con la electroencefalografia bispectral (BIS) y la presion arterial promedio (PAM). La ventilacion era mecanica y controlada a volumen; la via aerea se mantenia con mascara laringea. Los valores de las concentraciones en el local efector de propofol y remifentanil se obtenian a traves de los modelos farmacocineticos de los farmacos, insertados en las bombas de IAC y correspondieron a las concentraciones predictibles. El local efector se refiere al local de accion de los farmacos. El tiempo de alta comprendio el espacio de tiempo entre la llegada del paciente a la sala de recuperacion hasta el momento del alta. RESULTADOS: Las concentraciones promedios en el local efector (ng.mL-1), maximas y minimas de remifentanil fueron de 3,5 y 2,4 respectivamente. Las concentraciones promedios en el local efector (µg.mL-1), maximas y minimas de propofol, fueron respectivamente de 3,1 y 2,6. El caudal promedio de infusion de propofol y de remifentanil fue de 8,54 mg.kg-1.h-1 y de 0,12 µg.kg-1.min-1, respectivamente. Los tiempos de alta fueron como promedio de 180 min. CONCLUSIONES: Todos los pacientes se mantuvieron dentro de los parametros establecidos.BACKGROUND AND OBJECTIVES The increased popularity of minimally invasive surgical techniques reduced recovery time of procedures that were usually associated with prolonged hospitalization. This study reports the technique of total intravenous anesthesia with propofol and remifentanil associated with femoral nerve block using the inguinal perivascular approach. METHODS Ninety patients undergoing knee arthroscopy for meniscectomy were included in this study. Target-controlled infusion (TCI) of propofol (target = 4 microg.mL(-1)) and remifentanil (target = 3 ng.mL(-1)) was used for induction of anesthesia. The concentrations of propofol and remifentanil were changed according to the bispectral index (BIS) and mean arterial pressure (MAP). Volume-controlled mechanical ventilation with a laryngeal mask was used. The concentrations of propofol and remifentanil at the effector site, corresponding to the predictive concentrations, were obtained using the pharmacokinetic models of the drugs inserted in the TCI pumps. Time for hospital discharge encompassed the period between the moment the patient arrived at the recovery room and hospital discharge. RESULTS Maximal and minimal mean concentrations at the effector site (ng.mL(-1)) of remifentanil were 3.5 and 2.4, respectively. Maximal and minimal mean concentrations of propofol at the effector site (microg.mL(-1)) were 3.1 and 2.6, respectively. The mean flow of infusion of propofol and remifentanil was 8.54 mg.kg(-1).h(-1) and 0.12 microg.kg(-1).min(-1), respectively. Mean hospital discharge time was 180 min. CONCLUSIONS All patients were maintained within established parameters.