Lidocaine combined with magnesium sulfate preserved hemodynamic stability during general anesthesia without prolonging neuromuscular blockade: a randomized, double-blind, controlled trial.

BACKGROUND: Lidocaine and magnesium sulfate have become increasingly utilized in general anesthesia. The present study evaluated the effects of these drugs, isolated or combined, on hemodynamic parameters as well as on the cisatracurium-induced neuromuscular blockade (NMB). METHODS: At a university hospital, 64 patients, ASA physical status I and II, undergoing elective surgery with similar pain stimuli were randomly assigned to four groups. Patients received a bolus of lidocaine and magnesium sulfate before the tracheal intubation and a continuous infusion during the operation as follows: 3 mg.kg- 1 and 3 mg.kg- 1.h- 1 (lidocaine - L group), 40 mg.kg- 1 and 20 mg.kg- 1.h- 1 (magnesium - M group), equal doses of both drugs (magnesium plus lidocaine - ML group), and an equivalent volume of isotonic solution (control - C group). Hemodynamic parameters and neuromuscular blockade features were continuously monitored until spontaneous recovery of the train of four (TOF) ratio (TOFR > 0.9). RESULTS: The magnesium sulfate significantly prolonged all NMB recovery features, without changing the speed of onset of cisatracurium. The addition of lidocaine to Magnesium Sulfate did not influence the cisatracurium neuromuscular blockade. A similar finding was observed when this drug was used alone, with a significantly smaller fluctuation of mean arterial pressure (MAP) and heart rate (HR) measures during anesthesia induction and maintenance. Interestingly, the percentage of patients who achieved a TOFR of 90% without reaching T1-95% was higher in the M and ML groups. Than in the C and L groups. There were no adverse events reported in this study. CONCLUSION: Intravenous lidocaine plays a significant role in the hemodynamic stability of patients under general anesthesia without exerting any additional impact on the NMB, even combined with magnesium sulfate. Aside from prolonging all NMB recovery characteristics without altering the onset speed, magnesium sulfate enhances the TOF recovery rate without T1 recovery. Our findings may aid clinical decisions involving the use of these drugs by encouraging their association in multimodal anesthesia or other therapeutic purposes. TRIAL REGISTRATION: NCT02483611 (registration date: 06-29-2015).

Electroconvulsive Therapy Under General Anesthesia With Cisatracurium, Laryngeal Mask Airways, and Bispectral Index.

OBJECTIVES: Electroconvulsive therapy (ECT) has dramatically reduced musculoskeletal complications when carried out with muscle relaxants under general anesthesia. However, seizure quality can be affected by the depth of anesthesia and choice of anesthetic agent. The purpose of this study was to describe a general anesthetic technique for ECT by using laryngeal mask, bispectral index (BIS), and muscle relaxant monitoring. METHODS: Twenty-one patients, between ages 18 and 70 years (American Society of Anesthesiologists physical status I-III), who underwent a total of 89 sessions of ECT were examined in a retrospective study. Anesthesia was induced by use of propofol (1.0 mg/kg) followed by cisatracurium (0.2 mg/kg). The BIS, train-of-four, and end-tidal carbon dioxide were all monitored continuously. A laryngeal mask airway was used to maintain and protect the airway during the procedure. Electroconvulsive therapy stimuli were applied bilaterally when the train-of-four was assessed as being zero and BIS scores were 70. All patients then received 5 µg sufentanil and 2 mg midazolam, while titrated to maintain the BIS value at 40 to 50, before the muscle relaxation exhibited complete recovery. RESULTS: The mean duration of treatment process takes approximately 82.5 minutes. Mean (SD) seizure length was 58.8 (28.3) seconds, with 4.5% incidence of restimulation per treatment. Incidence of awareness was 0%. No patients exhibited delirium, nausea, vomiting, or myalgia in the postseizure phase. CONCLUSIONS: Bispectral index monitoring of the depth of anesthesia may have improved seizure quality, and awareness did not occur.

Influência dos Hipnóticos no bloqueio neuromuscular produzido pelo cisatracúrio: emprego da aceleromiografia / Influence of hypnotics on cisatracurium-induced neuromuscular block: use of acceleromyograhpy / Influencia de los hipnóticos en el bloqueo neuromuscular producido por el cisatracurio: uso de la aceleromiografía

JUSTIFICATIVA E OBJETIVOS: Os efeitos farmacodinâmicos dos bloqueadores neuromusculares (BNM) podem ser influenciados por diferentes drogas, entre elas os hipnóticos. O objetivo deste estudo foi avaliar a influência do propofol e do etomidato sobre o bloqueio neuromuscular produzido pelo cisatracúrio. MÉTODO: Foram incluídos 60 pacientes, ASA I e II, submetidos a cirurgias eletivas sob anestesia geral, distribuídos aleatoriamente em dois grupos de acordo com o hipnótico empregado: GI (propofol) e GII (etomidato). As pacientes receberam midazolam (0,1 mg.kg-1) por via muscular como medicação pré-anestésica, a indução foi com propofol (2,5 mg.kg-1) ou etomidato (0,3 mg.kg-1) precedido de fentanil (250 µg) e seguido de cisatracúrio (0,1 mg.kg-1). Os pacientes foram ventilados com oxigênio a 100% até a obtenção de redução de 95% ou mais na amplitude da resposta do adutor do polegar, quando foi feita a laringoscopia e a intubação traqueal. A função neuromuscular foi monitorizada com aceleromiografia. Avaliaram-se o início de ação do cisatracúrio, as condições de intubação traqueal e as repercussões hemodinâmicas. RESULTADOS: Os tempos médios e os desvios padrão para o início de ação do cisatracúrio foram: GI (86,6 ± 14,3") e GII (116,9 ± 11,6"), com diferença significativa (p < 0,0001). As condições de intubação traqueal foram aceitáveis em 100% dos pacientes do GI e em 53,3% no GII (p < 0,0001). CONCLUSÕES: A instalação do bloqueio neuromuscular com o cisatracúrio foi mais rápida e as condições de intubação traqueal foram melhores nos pacientes que receberam propofol em relação ao grupo que recebeu etomidato, sem repercussões hemodinâmicas.

BACKGROUND AND OBJECTIVE: Different drugs, including hypnotics, may influence the pharmacodynamic effects of neuromuscular blockers (NMB). The aim of this study was to evaluate the influence of propofol and etomidate on cisatracurium-induced neuromuscular blockade. METHOD: We included 60 patients, ASA I and II, undergoing elective surgery under general anesthesia in the study and randomly allocated them into two groups, according to their hypnotic drug: GI (propofol) and GII (etomidate). Patients received intramuscular (IM) midazolam (0.1 mg.kg-1) as premedication and we performed induction with propofol (2.5 mg.kg-1) or etomidate (0.3 mg.kg-1), preceded by fentanyl (250 mg) and followed by cisatracurium (0.1 mg.kg-1). The patients were ventilated with 100% oxygen until obtaining a reduction of 95% or more in the adductor pollicis response amplitude, with subsequent laryngoscopy and tracheal intubation. Neuromuscular function was monitored by acceleromyograhpy. We evaluated the onset of action of cisatracurium, tracheal intubation conditions, and hemodynamic repercussions. RESULTS: The mean time and standard deviations of cisatracurium onset were: GI (86.6 ± 14.3 s) and GII (116.9 ± 11.6 s), with a significant difference (p < 0, 0001). Intubation conditions were acceptable in 100% of GI and 53.3% of GII patients (p < 0.0001). CONCLUSION: Induction of neuromuscular blockade with cisatracurium was faster, with better intubation conditions in patients receiving propofol compared to those receiving etomidate, without hemodynamic repercussions.

JUSTIFICATIVA Y OBJETIVOS: Los efectos farmacodinámicos de los bloqueantes neuromusculares (BNM) pueden estar influenciados por diferentes fármacos, entre ellos los hipnóticos. El objetivo de este estudio, fue evaluar la influencia del propofol y del etomidato sobre el bloqueo neuromuscular producido por el cisatracurio. MÉTODO: Se incluyeron en el estudio 60 pacientes, con ASA I y II, sometidos a cirugías electivas bajo anestesia general, distribuidos aleatoriamente en dos grupos de acuerdo con el hipnótico usado: GI (propofol) y GII (etomidato). Las pacientes recibieron midazolam (0,1 mg.kg-1) por vía muscular como medicación preanestésica, la inducción fue con propofol (2,5 mg.kg-1) o etomidato (0,3 mg.kg-1) precedido de fentanilo (250 µg) y seguido de cisatracurio (0,1 mg.kg-1). Los pacientes fueron ventilados con oxígeno al 100% hasta la obtención de la reducción de un 95% o más en la amplitud de la respuesta del aductor del pulgar cuando se hizo la laringoscopia y la intubación traqueal. La función neuromuscular fue monitorizada con aceleromiografía. Se evaluaron el inicio de acción del cisatracurio, las condiciones de intubación traqueal y las repercusiones hemodinámicas. RESULTADOS: Los tiempos promedios y las desviaciones estándar para el inicio de acción del cisatracurio fueron: GI (86,6 ± 14,3") y GII (116,9 ± 11,6"), con una diferencia significativa (p < 0,0001). Las condiciones de intubación traqueal fueron aceptables en un 100% de los pacientes del GI y en 53,3% en el GII (p < 0,0001). CONCLUSIONES: La instalación del bloqueo neuromuscular con el cisatracurio fue más rápida y las condiciones de intubación traqueal fueron mejores en los pacientes que recibieron propofol con relación al grupo que recibió etomidato, sin repercusiones hemodinámicas.

Influence of hypnotics on cisatracurium-induced neuromuscular block. Use of acceleromyograhpy.

BACKGROUND AND OBJECTIVE: Different drugs, including hypnotics, may influence the pharmacodynamic effects of neuromuscular blockers (NMB). The aim of this study was to evaluate the influence of propofol and etomidate on cisatracurium-induced neuromuscular blockade. METHOD: We included 60 patients, ASA I and II, undergoing elective surgery under general anesthesia in the study and randomly allocated them into two groups, according to their hypnotic drug: GI (propofol) and GII (etomidate). Patients received intramuscular (IM) midazolam (0.1mg.kg(-1)) as premedication and we performed induction with propofol (2.5mg.kg(-1)) or etomidate (0.3mg.kg(1)), preceded by fentanyl (250mg) and followed by cisatracurium (0.1mg.kg(-1)). The patients were ventilated with 100% oxygen until obtaining a reduction of 95% or more in the adductor pollicis response amplitude, with subsequent laryngoscopy and tracheal intubation. Neuromuscular function was monitored by acceleromyograhpy. We evaluated the onset of action of cisatracurium, tracheal intubation conditions, and hemodynamic repercussions. RESULTS: The mean time and standard deviations of cisatracurium onset were: GI (86.6±14.3s) and GII (116.9±11.6s), with a significant difference (p<0, 0001). Intubation conditions were acceptable in 100% of GI and 53.3% of GII patients (p<0.0001). CONCLUSION: Induction of neuromuscular blockade with cisatracurium was faster, with better intubation conditions in patients receiving propofol compared to those receiving etomidate, without hemodynamic repercussions.

Comparison of the variability of the onset and recovery from neuromuscular blockade with cisatracurium versus rocuronium in elderly patients under total intravenous anesthesia

This study was designed to compare the variability of the onset and offset of the effect of two neuromuscular blocking drugs with different elimination pathways in adult and elderly patients during total intravenous anesthesia (TIVA). After Ethics Committee approval and patients’ informed consent, the drugs were compared in 40 adult and 40 elderly patients scheduled for elective surgery under TIVA with tracheal intubation who were randomized to receive a single bolus dose of 0.15 mg/kg cisatracurium or 0.9 mg/kg rocuronium. The time of onset of maximum depression, duration of action, and recovery index time were measured and recorded for each patient and variability is reported as means ± standard deviation. Time of onset was significantly shorter for rocuronium than cisatracurium for the adult and elderly groups (P = 0.000), but the variability of cisatracurium was significantly greater compared with rocuronium for the same age groups (93.25 vs 37.01 s in the adult group and 64.56 vs 33.75 s in the elderly group; P = 0.000). The duration of the effect in the elderly group receiving rocuronium was significantly longer than in the elderly group receiving cisatracurium, and the variability of the duration was significantly greater in the rocuronium group than in the cisatracurium group. Mean time of recovery was significantly longer for the elderly group receiving rocuronium than for the elderly group receiving cisatracurium (P = 0.022), and variability was also greater (P = 0.002). Both drugs favored good intubating conditions. In conclusion, cisatracurium showed less variability in these parameters than rocuronium, especially in the elderly, a fact that may be of particular clinical interest.

Comparison of the variability of the onset and recovery from neuromuscular blockade with cisatracurium versus rocuronium in elderly patients under total intravenous anesthesia.

This study was designed to compare the variability of the onset and offset of the effect of two neuromuscular blocking drugs with different elimination pathways in adult and elderly patients during total intravenous anesthesia (TIVA). After Ethics Committee approval and patients' informed consent, the drugs were compared in 40 adult and 40 elderly patients scheduled for elective surgery under TIVA with tracheal intubation who were randomized to receive a single bolus dose of 0.15 mg/kg cisatracurium or 0.9 mg/kg rocuronium. The time of onset of maximum depression, duration of action, and recovery index time were measured and recorded for each patient and variability is reported as means ± standard deviation. Time of onset was significantly shorter for rocuronium than cisatracurium for the adult and elderly groups (P = 0.000), but the variability of cisatracurium was significantly greater compared with rocuronium for the same age groups (93.25 vs 37.01 s in the adult group and 64.56 vs 33.75 s in the elderly group; P = 0.000). The duration of the effect in the elderly group receiving rocuronium was significantly longer than in the elderly group receiving cisatracurium, and the variability of the duration was significantly greater in the rocuronium group than in the cisatracurium group. Mean time of recovery was significantly longer for the elderly group receiving rocuronium than for the elderly group receiving cisatracurium (P = 0.022), and variability was also greater (P = 0.002). Both drugs favored good intubating conditions. In conclusion, cisatracurium showed less variability in these parameters than rocuronium, especially in the elderly, a fact that may be of particular clinical interest.

Hemodynamic effects of atracurium and cisatracurium and the use of diphenhydramine and cimetidine.

BACKGROUND AND OBJECTIVES: Since atracurium can cause hypotension in humans, the hemodynamic effects of atracurium and cisatracurium as well as the hemodynamic protection of diphenhydramine and cimetidine were investigated in rats. METHODS: 1) Wistar rats were anesthetized with sodium pentobarbital and prepared according to Brown et al. to evaluate different doses of atracurium and cisatracurium in the reduction of T4/T1 equal or greater than 95%. 2) Assessment of the hemodynamic changes caused by the intravenous administration of atracurium and cisatracurium by monitoring the blood pressure in the carotid artery and the electrocardiogram of rats. 3) Observation of the hemodynamic protection of prior treatment with the intravenous administration of diphenhydramine (2 mg.kg(-1)) and/or cimetidine (4 mg.kg(-1)). STATISTICAL ANALYSIS: Student t test and ANOVA. RESULTS: Doses of 1 mg.kg(-1) and 0.25 mg.kg(-1) of atracurium and cisatracurium respectively did not change the mean arterial pressure (MAP). Doses of 4 mg.kg(-1) of atracurium and cisatracurium decreased MAP to 62.8 +/- 4.5% and 82.5 +/- 2.3% respectively when compared to control levels. When the rats were pre-treated with diphenhydramine and cimetidine, diastolic pressure was reduced to 95.4% +/- 2.5%. With cimetidine, diastolic pressure was reduced to 82.7 +/- 8.4% when compared to the control group. The effects on systolic and diastolic blood pressure were reflected in the levels of MAP. CONCLUSIONS: The isolated administration of diphenhydramine and cimetidine did not prevent the reduction in mean arterial pressure induced by atracurium. However, the association of both drugs was able to prevent the hemodynamic effects of atracurium. The doses of cisatracurium used in this study did not cause a reduction in blood pressure significant enough to justify the use of the preventive measures used in the atracurium groups.

Presynaptic M1, M2, and A1 receptors play roles in tetanic fade induced by pancuronium or cisatracurium.

PURPOSE: We investigated whether presynaptic facilitatory M1 and/or inhibitory M2 muscarinic receptors contributed to pancuronium- and cisatracurium-induced tetanic fade. METHODS: Phrenic nerve-diaphragm muscle preparations of rats were indirectly stimulated with tetanic frequency (75 +/- 3.3 Hz; mean +/- SD). Doses of pancuronium, cisatracurium, hexamethonium, and d-tubocurarine for producing approximately 25% fade were determined. The effects of pirenzepine and methoctramine, blockers of presynaptic M1 and M2 receptors, respectively, on the tetanic fade were investigated. RESULTS: The concentrations required for approximately 25% fade were 413 microM for hexamethonium (26.8 +/- 2.4% 4% fade), 55 nM for d-tubocurarine (28.7 +/- 2.55% fade), 0.32 microM for pancuronium (25.4 +/- 2.2% fade), and 0.32 microM for cisatracurium (24.7 +/- 0.8% fade). Pirenzepine or methoctramine alone did not produce the fade. Methoctramine, 1 microM, attenuated the fade induced by hexamethonium (to 16.0 +/- 2.5% fade), d-tubocurarine (to 6.0 +/- 1.6 fade), pancuronium (to 8.0 +/- 4.0% fade), and cisatracurium (to 11.0 +/- 3.3% fade). 10 nM pirenzepine attenuated only the fades produced by pancuronium (to 5.0 +/- 0.11% fade) and cisatracurium (to 13.3 +/- 5.3% fade). Cisatracurium (0.32 microM) showed antiacetylcholinesterase activity (in plasma, 14.2 +/- 1.6%; 6%; in erythrocyt 17.2 +/- 2.66%) similar to that of pancuronium (0.32 microM). The selective A1 receptor blocker, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX; 2.5 nM), also attenuated the fades induced by pancuronium and cisatracurium. CONCLUSION: The tetanic fades produced by pancuronium and cisatracurium depend on the activation of presynaptic inhibitory M2 receptors; these agents also have anticholinesterase activities. The fades induced by these agents also depend on the activation of presynaptic inhibitory A1 receptors through the activation of stimulatory M1 receptors by acetylcholine.

[Effect of propofol in combination with ephedrine upon the onset time of cisatracurium]. / Efeito do propofol associado à efedrina no tempo de latência do cisatracúrio.

OBJECTIVE: The onset time of neuromuscular blocking drugs is partially determined by circulatory factors, including muscle blood flow and cardiac output. The aim of the present paper was to: 1) compare the haemodynamic effects of adding different doses of ephedrine to an induction dose of propofol and remifentanil. 2) onset time of cisatracurium. METHODS: Sixty patients were randomly allocated into three groups: G1 - 1% propofol; G2 - 1% propofol + 0.5 mg.ml-1 ephedrine and G3 - 1% propofol + 1.0 mg.ml-1 ephedrine. All patients received continuous infusion of remifentanil (0.5 mg.kg-1.min-1). The rate of propofol infusion was 180 ml.h-1 until loss of consciousness and a loading dose of cisatracurium (0.15 mg.kg-1) was then given. After induction of anesthesia, the ulnar nerve was stimulated supramaximally every 10s, and the evoked twitch response of the adductor pollicis was recorded by accelerometry. RESULTS: There was no statistical difference between groups with respect to age, weight, dose of propofol administered and onset time of cisatracurium. Heart rate, SpO2, systolic, diastolic and mean blood pressures were compared at 1 and 3 min post-induction. There were statistical differences in HR, SAP, DAP and MAP, without significant adverse clinical effects. CONCLUSIONS: There were no clinically important decreases in the hemodynamic parameters evaluated in the groups receiving ephedrine or not, and the onset time of cisatracurium was the same for all groups.

Efeito do propofol associado à efedrina no tempo de latência do cisatracúrio / Effect of propofol in combination with ephedrine upon the onset time of cisatracurium

OBJETIVOS: Este estudo teve por objetivo avaliar a eficácia da efedrina na prevenção dos efeitos hemodinâmicos induzidos pela associação do propofol e do remifentanil, assim como os efeitos sobre o tempo de latência do cisatracúrio. MÉTODOS: Sessenta pacientes com idade entre 18 e 52 anos, estado físico ASA I ou II, foram divididos em três grupos, aleatoriamente: G I - propofol 1 por cento; G II - propofol 1 por cento + efedrina 0,5 mg.ml-1 e G III - propofol 1 por cento + efedrina 1,0 mg.ml-1 (velocidade de infusão igual a 180 ml.h-1), até a perda da consciência. Administrou-se remifentanil (0,5 mg.kg-1.min-1) e cisatracúrio na dose de 0,15 mg.kg-1. Foram registrados os dados demográficos, os sinais vitais (PAS, PAM, PAD, FC e SpO2) e o tempo de latência do cisatracúrio. RESULTADOS: Os grupos foram homogêneos com relação aos dados demográficos. Houve diminuição estatisticamente significativa dos valores de PAS, PAM, PAD e FC, um e três minutos após a administração do propofol, porém sem significado clínico importante e sem diferença entre os grupos. As medianas para os tempos de latência do cisatracúrio foram: 178 s (G2 e G3) e 183 s (G1), mas sem diferença significante entre os grupos. CONCLUSÃO: Não houve diminuição clinicamente importante dos parâmetros hemodinâmicos avaliados nos grupos que receberam ou não a efedrina e o tempo de latência do cisatracúrio foi o mesmo para os diferentes grupos.

OBJECTIVE: The onset time of neuromuscular blocking drugs is partially determined by circulatory factors, including muscle blood flow and cardiac output. The aim of the present paper was to: 1) compare the haemodynamic effects of adding different doses of ephedrine to an induction dose of propofol and remifentanil. 2) onset time of cisatracurium. METHODS: Sixty patients were randomly allocated into three groups: G1 - 1 percent propofol; G2 - 1 percent propofol + 0.5 mg.ml-1 ephedrine and G3 - 1 percent propofol + 1.0 mg.ml-1 ephedrine. All patients received continuous infusion of remifentanil (0.5 mg.kg-1.min-1). The rate of propofol infusion was 180 ml.h-1 until loss of consciousness and a loading dose of cisatracurium (0.15 mg.kg-1) was then given. After induction of anesthesia, the ulnar nerve was stimulated supramaximally every 10s, and the evoked twitch response of the adductor pollicis was recorded by accelerometry. RESULTS: There was no statistical difference between groups with respect to age, weight, dose of propofol administered and onset time of cisatracurium (tables 1, 2). Heart rate, SpO2, systolic, diastolic and mean blood pressures were compared at 1 and 3 min post-induction. There were statistical differences in HR, SAP, DAP and MAP, without significant adverse clinical effects. CONCLUSIONS: There were no clinically important decreases in the hemodynamic parameters evaluated in the groups receiving ephedrine or not, and the onset time of cisatracurium was the same for all groups.

Cisatracurium: myographical and electrophysiological studies in the isolated rat muscle.

Myographical and electrophysiological studies of cisatracurium were performed, in vitro, in the isolated sciatic nerve-extensor digitorum longus muscle preparation of the rat. Indirect twitches were generated at 0.1 Hz and tetanic contractions at 50 Hz. endplate potentials (epps) were generated in trains of 50 Hz. The electrophysiological variables used in the analysis of the epps were: amplitude of the first epp in the train, average amplitude of the 30 degrees to the 59 degrees epp in the train (epps-plateau), tetanic rundown (percent loss in amplitude of epps-plateau relative to the first epp in the train), quantal size and quantal content. The myographical results showed that the inhibitory concentration 50% (IC(50)) of cisatracurium for the blockade of twitches (0.48 microm) is 12 times its IC(50) for the induction of tetanic fade (0.04 microm). The electrophysiological results showed a concentration dependent decrease in the amplitudes of first epps in the trains and of epps-plateau in the two used concentrations (0.13 microm and 0.38 microm). The tetanic rundown was intensified only in the presence of the higher (0.38 microm) concentration of cisatracurium. In cisatracurium 0.13 microm (a concentration which affects only tetanic contractions, inducing their fade, while leaving the twitch unaffected) there was a decrease in the quantal content of the first epp and of epps-plateau in the train. In cisatracurium (0.38 microm), a concentration, which affects the twitch, there was a decrease of the quantal size and of quantal content of epps-plateau, but not of the quantal content of the first epp in the train. The results indicate that the fade of the tetanic contraction induced by cisatracurium at the concentration of 0.13 microm is entirely because of a pre-synaptic blocking effect while the decrease in the twitch induced by cisatracurium at the concentration of 0.38 microm is due to a post-synaptic blocking effect.

Anestesia venosa total para laringectomia parcial em paciente na 28ª semana de gestação: relato de caso / Total intravenous anesthesia for partial laryngectomy in 28 weeks pregnant patient: case report

JUSTIFICATIVA E OBJETIVOS: Uma anestesia para paciente gestante constitui um desafio ao anestesiologista em virtude dos riscos para a mãe e para o feto. São muitas as complicações descritas pela literatura como malformações fetais, parto prematuro, instabilidade hemodinâmica materna e até morte fetal. O objetivo deste caso é mostrar uma paciente gestante de 28 semanas, submetida a laringectomia parcial sob anestesia geral venosa total com propofol, remifentanil e cisatracúrio. RELATO DO CASO: Paciente com 29 anos, 59 kg, primigesta de 28 semanas com diagnóstico prévio de carcinoma epidermóide próximo à corda vocal direita, sendo indicada laringectomia. A monitorização inicial constituiu-se de pressão arterial não-invasiva e invasiva, cardioscopia, oxicapnografia e cardiotocografia contínua realizada pela obstetra. Punção venosa no membro superior direito e membro superior esquerdo com cateter 16G e 18G, respectivamente. Foram administrados por via venosa midazolam (1 mg), cefazolina (1 g), metoclopramida (10 mg) e dipirona (1 g). A paciente recebeu oxigênio a 100 por cento sob máscara por 3 minutos e indução venosa foi feita com o uso de propofol em infusão na dose alvo de 3 æg.mL-1 e remifentanil contínuo (1 æg.kg-1 em bolus e 0,2 æg.kg-1.min-1 de manutenção). Como bloqueador neuromuscular, foi administrado cisatracúrio (13 mg) e procedeu-se a intubação traqueal com tubo 6,5 mm aramado com balonete. Foi mantida em plano anestésico com propofol e remifentanil em bomba, além de complementações de cisatracúrio. O feto permaneceu monitorizado continuamente com cardiotocografia realizada e analisada pela obstetra. Após o término da cirurgia foram desligadas as bombas infusoras de propofol e remifentanil, tendo a paciente despertado 10 minutos depois. Acordou sem dor e hemodinamicamente estável, sendo então encaminhada à sala de recuperação pós-anestésica. CONCLUSÕES: A anestesia venosa total com propofol e remifentanil proporcionou estabilidade hemodinâmica para a mãe e o feto, com um despertar precoce e suave.

Uso de bloqueadores neuromusculares em pacientes em miastenia gravis: relato de dois casos / Neuromuscular blockers in myasthenia gravis patients: report of two cases

Justificativa e objetivos - Existe uma grande diversidade na gravidade da Miastenia Gravis, assim como na dose e resposta aos bloqueadores neuromusculares (BNM). O objetivo deste relato é apresentar dois casos de bloqueio neuromuscular prologando com cisatracúrio e mivacúrio, em pacientes com Miastenia Gravis. Relatos dos Casos - Caso n§1 - Paciente masculino, 55 anos, 82 kg, com história de Miastenia Gravis submetido a timectomia por via transternal, sob anestesia geral com propofol, alfentanil, isoflurano e óxido nitroso. Para intubaçäo traqueal foi utilizado cisatracúrio (1,2mg). Após 3:45h de cirurgia, a reversäo com neostigmina foi considerada insatisfatória e o paciente teve que permanecer intubado por duas horas. Somente após este período a descurarizaçäo considerada satisfatória (T4/T1 em 0,9) e o paciente foi extubado. Caso n§2 - Paciente do sexo feminino, 42 anos, 59 kg, submetida à histerectomia por via vaginal sob anestesia combinada (peridural e geral). Foi feita monitorizaçäo da transmissäo neuromuscular antes da injeçäo de mivacúrio (0,2mg.kg-1) e notou-se intensa fadiga. Após 3:30h a relaçäo T4/T1 estava 0,15, havendo resposta a injeçäo de neostigmina (0,05µg.kg-1). Posteriormente foi diagnosticada Miastenia Gravis. Conclusöes - O uso de monitores de transmissäo neuromuscular, näo deve ficar restrito aos pacientes miastênicos, pois a diversidade das respostas aos BNM é comum nos pacientes normais

Farmacodinâmica do cisatracúrio no transplante renal / Pharmacodynamics of cisatracurium in renal transpantation

Objetivo: Determinar, em doentes portadores de insuficiência renal crônica, a farmacodinâmica do cisatracúrio durante o transplante renal. Métodos: Foram estudados 30 doentes divididos em dois grupos, 15 com funçao renal normal submetidos a cirurgia bucomaxilo-facial e 15 portadores de insuficiência renal crônica submetidos a transplante renal, submetidos a anestesia geral com etomidato, sufentanil e sevoflurano em concentraçoes inferiores a 1 por cento de fraçao expirada. Receberam dose venosa de 0,15 mg.kg-' de cisatracúrio na induçao e 0,05 mg.kg-' todas as vezes que Ti recuperava 25 por cento. A funçao neuromuscular foi monitorizada de forma contínua no membro superior pelo monitor TOF guard (Dinamark), utilizando o padrao de estimulaçao TOF (train-of-four ou sequência de quatro estímulos), através da estimulaçao supramáxima do nervo ulnar. Resultados: Os resultados referentes à farmacodinâmica do cisatracúrio mostram que o início de açao, a duraçao clínica e o índice de recuperaçao foram semelhantes entre os grupos. Os tempos para a relaçao T4/T1 atingir 0,7 e 0,9 a partir do último 25 por cento de Ti apresentaram diferença estatisticamente significante entre os grupos, com os maiores valores no grupo renal. Conclusao: Dos parâmetros farmacodinâmicos estudados, apenas a recuperaçao tardia prolongada nos doentes portadores de insuficiência renal crônica submetidos a transplante renal

Total intravenous anesthesia with midazolam, remifentanil, propofol and cistracurium in morbid obesity.

BACKGROUND: According to physical impairments of massive obesity, cardiac, respiratory and gastrointestinal physiology must be considered as much as pharmacokinetic behavior. Anesthetic management of morbidly obese patients has to be carefully planned, in order to minimize the increased risks of aspirative pneumonitis, hemodynamic instability and delay in recovery. The ideal anesthesia should provide a smooth and quick induction, allowing rapid airway control, prominent hemodynamic stability, and rapid emergence from anesthesia. To approach these ideal conditions, a Total Intravenous Anesthesia (TIVA) with midazolam, remifentanil, propofol and cisatracurium was designed and analyzed. METHODS: 10 consenting morbidly obese patients scheduled for elective Laparoscopic Adjustable Gastric Banding participated in the study. TIVA with midazolam, remifentanil, propofol and cisatracurium was used in all cases. Time to loss of consciousness, tracheal intubation, perianesthetic physiological parameters and complications, incidence of awareness with recall, recovery times, postoperative analgesia and costs of drugs were evaluated. RESULTS: The analyzed data showed adequate time and physiological conditions for induction and tracheal intubation, stable maintenance with easy handling of deepness, low incidence of perianesthetic complications, excellent recovery performance and institutional efficiency. CONCLUSIONS: TIVA with midazolam, remifentanil, propofol and cisatracurium was found to be effective, secure, predictable and economic for the anesthetic management of morbidly obese patients.