Influence of different local anesthetics on atracurium neuromuscular blockade on rats / Influência de diferentes anestésicos locais no bloqueio neuromuscular produzido pelo atracúrio em ratos

Abstract Introduction: The association between local anesthetics (LA) and neuromuscular blocking (NMB) drugs in clinical practice, and the possibility of interaction between these drugs has been investigated. LAs act on neuromuscular transmission in a dose-dependent manner and may potentiate the effects of NMB drugs. Objective: The aim of this study was to evaluate, in an experimental model, the effect of lidocaine and racemic bupivacaine on neuromuscular transmission and the influence on neuromuscular blockade produced by atracurium. Methods: Male Wistar rats, weighing from 250 to 300 g were used. The preparation was set up based on a technique proposed by Bülbring. Groups were formed (n = 5) according to the drug studied: lidocaine 20 µg.mL−1 (Group I); racemic bupivacaine 5 µg.mL−1 (Group II); atracurium 20 µg.mL−1 (Group III); atracurium 20 µg.mL−1 in a preparation previously exposed to lidocaine 20 µg.mL−1 and racemic bupivacaine 5 µg.mL−1, Groups IV and V, respectively. The following parameters were assessed: 1) Amplitude of hemi diaphragmatic response to indirect stimulation before and 60 minutes after addition of the drugs; 2) Membrane potentials (MP) and miniature endplate potentials (MEPPs). Results: Lidocaine and racemic bupivacaine alone did not alter the amplitude of muscle response. With previous use of lidocaine and racemic bupivacaine, the neuromuscular blockade (%) induced by atracurium was 86.66 ± 12.48 and 100, respectively, with a significant difference (p = 0.003), in comparison to the blockade produced by atracurium alone (55.7 ± 11.22). These drugs did not alter membrane potential. Lidocaine initially increased the frequency of MEPPs, followed by blockade. With the use of bupivacaine, the blockade was progressive. Conclusions: Lidocaine and racemic bupivacaine had a presynaptic effect expressed by alterations in MEPPs, which may explain the interaction and potentiation of NMB produced by atracurium.

Resumo Introdução: A associação de anestésicos locais (AL) com bloqueadores neuromusculares (BNM) na prática clínica e a possibilidade de interação entre esses fármacos têm sido investigadas. Objetivo: Avaliar, em modelo experimental, o efeito da lidocaína e da bupivacaína racêmica na transmissão neuromuscular e sua influência no bloqueio neuromuscular produzido pelo atracúrio. Método: Ratos machos da linhagem Wistar, peso entre 250 e 300 g. A preparação foi feita de acordo com a técnica proposta por Bulbring. Grupos (n = 5) de acordo com o fármaco em estudo: lidocaína 20 µg.mL-1 (Grupo I); bupivacaína racêmica 5 µg.mL-1 (Grupo II); atracúrio 20 µg.mL-1 (Grupo III); atracúrio 20 µg.mL-1 em preparação previamente exposta a lidocaína 20 µg.mL-1 e bupivacaína racêmica 5 µg.mL-1, Grupos IV e V, respectivamente. Foram avaliados: 1) A amplitude das respostas do hemidiafragma à estimulação indireta antes e 60 minutos após a adição dos fármacos; 2) Os potenciais de membrana (PM) e os potenciais de placa terminal em miniatura (PPTM). Resultados: Os AL, isoladamente, não alteraram a amplitude das respostas musculares. Com o uso prévio dos AL, o bloqueio neuromuscular (%) do atracúrio foi 86,66 ± 12,48 e 100, respectivamente, com diferença significante (p= 0,003) em relação ao produzido pelo atracúrio isoladamente (55,7 ± 11,22). Não alteraram o PM. A lidocaína inicialmente aumentou a frequência dos PPTM, seguido de bloqueio; com a bupivacaína, o bloqueio foi progressivo. Conclusão: A lidocaína e a bupivacaína racêmica apresentaram efeito pré-sináptico expresso por alterações nos PPTM, podem justificar a potencialização do bloqueio neuromuscular produzido pelo atracúrio.

Effects of atracurium besylate on corneal endothelium of chickens: in vitro study / Avaliação dos efeitos do besilato de atracúrio no endotélio corneano de galinhas: estudo in vitro

The aim of this study was to investigate the acute effects of atracurium besylate on cellular damage in corneal endothelium of chickens. Twenty healthy chicken eyes were assigned to the following groups: Group 1 (G1), experimental group (n=10); and Group 2 (G2), control (n=10). Excised corneoscleral buttons were immediately placed on glass microscopy slides with endothelial region faced up. Corneal endothelium of eyes in G1 were covered with AB (0.2mL, 10mg/mL) for 3 min and then rinsed with balanced salt solution (BSS), while the corneal endothelium of eyes in G2 were covered with BBS for 3 min. Corneas from both groups were stained with alizarin red/trypan blue and visualized by light microscopy. Ten random photographs were taken from each cornea. The area of cellular damage was measured by software in all samples and cell loss of each group was averaged and compared. Endothelial area of denudation and Descemet's membrane exposure were higher in G1 than G2. In conclusion, atracurium besylate induced an acute damage on corneal endothelium of chickens.(AU)'

Objetivou-se avaliar os efeitos agudos do besilato de atracúrio sobre o endotélio corneano de galinhas. Vinte olhos saudáveis de galinhas foram aleatoriamente separados em dois grupos com 10 olhos cada, sendo G1 o grupo controle e G2 o grupo tratamento. Imediatamente após a excisão dos botões corneoesclerais estes foram colocados em lâminas de microscopia de vidro com o lado endotelial voltado para cima. No Grupo 1, o endotélio corneano foi recoberto com 0,2ml de besilato de atracúrio (10mg/ml) durante 3 minutos e depois lavado com solução salina balanceada. No Grupo 2, o endotélio corneano foi recoberto apenas com solução salina balanceada durante 3 min. As córneas de ambos os grupos foram coradas com vermelho de alizarina e azul de tripano e visualizadas com microscópio óptico. Foram obtidas dez fotografias aleatórias de cada amostra. As imagens foram analisadas e com auxílio de um software as áreas com ausência de células endoteliais calculadas. A perda celular endotelial foi significativamente maior no grupo tratamento comparativamente ao grupo controle. Com base nos resultados apresentados foi possível concluir que o besilato de atracúrio induziu dano agudo nas células do endotélio da córnea de galinhas.(AU)

Estimation of the effect-site equilibration rate constant using the time-to-peak effect of muscle relaxants measured by train-of-four stimulation during general anesthesia induction / 대한마취과학회지

BACKGROUND: The concept of the effect-site concentration of anesthetic agents is important. The effect compartment model can be explained using the concepts of effect-site concentration and effect-site equilibration rate constant (k e0). This study confirms that the time-to-peak effect (tpe ) can be measured easily in clinical practice by applying a priming dose and train-of-four (TOF) during general anesthesia induction, and k e0 can be calculated from the tpe of the four muscle relaxants that are commonly used in general anesthesia. METHODS: Eighty patients who received general anesthesia were divided into the succinylcholine, rocuronium, atracurium, or vecuronium groups. Priming doses of muscle relaxants were administered. The effects of muscle relaxants were quantified by recording the twitch response of the adductor pollicis muscle after stimulating the ulnar nerve. The tpe was measured at the lowest TOF value. k e0 was calculated from the measured tpe . RESULTS: The k e0 values of the succinylcholine, rocuronium, atracurium, and vecuronium groups were 0.076 (0.030)/min, 0.228 (0.122)/min, 0.062 (0.011)/min, and 0.077 (0.019)/min, respectively. CONCLUSIONS: It is possible to estimate k e0 from the tpe of muscle relaxants using a priming dose and TOF during general anesthesia induction.

Seguridad en anestesia: error en la administración de fármacos LASA / Safety in anesthesia: an error in the administration of LASA drugs / Segurança na anestesia: um erro na administração de drogas LASA

La seguridad del paciente es prioritaria en el ámbito anestésico quirúrgico. El error en la administración de fármacos es una causa frecuente de incidentes críticos en el perioperatorio. Una forma de error, es la administración del medicamento equivocado debido a las presentaciones similares. El objetivo de este trabajo es la descripción de fallas en las barreras de prevención de incidentes críticos con medicamentos, en base al estudio de un caso clínico y al análisis de sus consecuencias. Metodología : Descripción de un caso clínico y estudio sistemático de la situación de riesgo en base al análisis taxonómico del paciente, individuo, tarea, equipo humano, lugar de trabajo y organización (PITELO) sugerido por el Sistema Español de Notificación en Seguridad en Anestesia y Reanimación (SENSAR). Resultados : Mujer sana que presentó paro respiratorio luego de la administración intravenosa de un fármaco en el postoperatorio. Se requirió 24 hs de terapia intensiva y múltiples estudios, luego de lo cual se diagnosticó un error en la administración de fármaco. La confusión se presentó con una dupla de ampollas LASA (del inglés: look-alike, sound-alike) de los fármacos atracurio y ranitidina. La documentación fotográfica evidencia la similitud y el diagrama identifica fallas latentes del sistema. Se estimaron los costos del error y se realizaron propuestas de mejora. Discusión y conclusiones : Se evidencia una falla en las barreras de prevención de eventos adversos y en el sistema de reporte de los mismos. Es necesario incrementar la cultura de seguridad en todos los niveles del sistema: regulatorio, institucional y personal.

Patient safety is a priority in the surgical anesthetic area, and errors in drug administration area frequent cause of critical incidents in the perioperative period. One type of error is the administration of the wrong medication due to similar presentations. The objective of this study is to describe the failure of barriers to prevent critical drug incidents; this is based on the study of a clinical case and an analysis of its consequences. Methodology . Description of a clinical case and systematic study of the risk situation based on the taxonomic analysis of the patient, individual, task, human team, workplace, and organization (PITELO), as suggested by the Spanish System of Safety Notification in Anesthesia and Resuscitation (SENSAR). Results . A healthy woman presented in respiratory arrest after the intravenous administration of a drug in the postoperative period. It took 24 hours of intensive care and multiple studies before an error in drug administration was diagnosed. The confusion was presented with a pair of LASA (look-alike, sound-alike) ampoules of atracurium and ranitidine drugs. Photographic documentation evidences the similarity of the ampoules themselves, and the diagram identifies latent system failures. The costs of the error are estimated and proposals for improvement are provided. Discussion and Conclusions . There is evidence of a failure in the barriers to the prevention of adverse events and in the reporting system. It is necessary to increase the safety culture at all levels of the system: regulatory, institutional, and personal.

A segurança do paciente é prioritária no âmbito anestésico cirúrgico. O erro na administração de fármacos é uma causa frequente de incidentes críticos no perioperatório. Uma forma de erro é a administração de medicação errada devido a uma apresentação similar. O objetivo deste trabalho é a descrição de falhas nas barreiras de prevenção de incidentes críticos com medicamentos, em base no estudo de um caso clínico e ao análise de suas consequências. Metodologia . Descrição de um caso clínico e estudo sistemático da situação de risco em base ao análises taxonômico do doente, tarefa, equipamento humano, lugar de trabalho e organização (PITELO) sugerido pelo Sistema Espanhol de Notificação em Segurança em Anestesia e Reanimação (SENSAR). Resultados . Mulher sem patologia que apresentou paro respiratório a pois a administração intravenosa de um fármacos no pós-operatório. Requereu-se de 24 hs na UTI e múltiplos estudos, logo dos quais foi diagnosticado um erro na administração do fármaco. A confusão se apresentou como causa deduplas ampolas LASA (do inglês: aparência parecida com o som) dos fármacos atracurio y ranitidina. A documentação fotográfica evidencia a similitude e o diagrama identificafalhas latentes no sistema. Foram analisados os custos do erro e realizou-se propostas de melhora. Discussão y conclusões . Evidencia-se uma falla nas barreiras de prevenção de eventos adversos e no sistema de reporte dos mesmos. É necessário incrementar a cultura de segurança em todos os níveis do sistema: regulatório, institucional e pessoal.

Pharmacokinetics of a cisatracurium dose according to fat-free mass for anesthesia induction in morbidly obese patients / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the pharmacokinetics of cisatracurium between normal weight patients and morbidly obese patients.</p><p><b>METHODS</b>Twelve obese ASA I-II patients (BMI≥35 kg/m) undergoing laparoscopic Roux-en-Y gastric bypass and 12 normal weight ASA I-II patients (BMI of 18.5-24 kg/m) undergoing laparoscopic surgery were enrolled. The obese patients were given a cisatracurium dose of 0.15 mg/kg according to the fat-free mass (FFM), and the non-obese patients received a dose of 0.15 mg/kg according to the total body weight. Plasma concentrations of cisatracurium was monitored in the patients with high-performance liquid chromatography (HPLC) before anesthetic induction and at 1, 2, 4, 6, 8, 10, 12, 15, and 20 min after cisatracurium administration and the pharmacokinetic parameters were computed. SBP, DBP, HR, MAP, SpOand PetCOwere recorded before anesthetic induction (T) and at 1 min (T), 2 min (T), 4 min (T) after cisatracurium administration.</p><p><b>RESULTS</b>Compared with those measured at T, SBP, DBP and MAP in the 2 groups were significantly decreased at the time points of T(P<0.05). Compared with the non-obese patients, the obese patients showed significantly increased Hct level (P<0.05). The total clearance, apparent volume of distribution, and distribution and elimination half-life of the drug were similar between the 2 groups (P>0.05). The plasma concentration of cisatracurium at Twas significantly decreased in the obese patients compared with that in the non-obese patients (P<0.05).</p><p><b>CONCLUSION</b>Cisatracurium doses according to fat-free mass is clinically reasonable for inducing anesthesia in morbidly obese patients, but due to a prolonged muscle relax onset time, the timing of tracheal intubation should be delayed by 1-2 min.</p>

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.

Effect of addition of tramadol to one MAC sevoflurane on the haemodynamic response to laryngoscopy and tracheal intubation

To evaluate the effect of tramadol 2 mg/kg on haemodynamic response to tracheal intubation where the end tidal concentration of sevoflurane was kept constant at 1 MAC [2%]. study Design: Double blind randomized controlled trial. The Aga Khan University Hospital, Karachi, from January 2009 to April 2009. Thirty-four patients scheduled for surgery under general anaesthesia were randomly allocated to two groups, sevoflurane alone [2%] or sevoflurane [2%] and tramadol [2 mg/kg] combination. Anaesthesia was induced with thiopentone and atracurium and with either tramadol or placebo according to group allocation. Sevoflurane was administrated along with N2O and oxygen through the face mask till end tidal minimum alveolar concentration [MAC] of one [2%] was achieved. Haemodynamic changes were noted at 1, 2 and 3 minutes post induction and every minute upto 7 minutes post-intubation and compared with baseline values. A significant difference in heart rate was seen at 2 and 3 minutes post-induction and 1, 2 and 3 minutes postintubation between two groups with values higher in sevoflurane alone group. No significant difference was seen in systolic, diastolic, and mean blood pressure compared to baseline between the two groups. HR and SBP values following laryngoscopy and tracheal intubation in both groups were less than 20% of baseline. Addition of tramadol 2 mg/kg to 1 MAC sevoflurane displayed further depression of chronotropic response to laryngoscopy and intubation as compared to sevoflurane alone following thiopentone and atracurium induction

Anesthetic experience using total intravenous anesthesia in a patient with Isaacs' syndrome: A case report / 대한마취과학회지

We report on an anesthetic experience with a 74-year-old female with Isaacs' syndrome, who underwent elective surgery for open rotator cuff repair. Isaacs' syndrome is a rare peripheral motor neuron disorder with clinical manifestations such as involuntary muscle twitching, cramps, mild weakness and increased sweating. To avoid prolonged neuromuscular blockade, the patient was observed with neuromuscular monitoring during total intravenous anesthesia with propofol, remifentanil, and atracurium. No adverse events were observed during the anesthetic management, and the patient recovered smoothly from the neuromuscular blockade. We describe the clinical characteristics of Isaacs' syndrome and its specific considerations in anesthesia.

Anesthesiologist's satisfaction using between cisatracurium and rocuronium for the intubation in the anesthesia induced by remifentanil and propofol / 대한마취과학회지

BACKGROUND: Although cisatracurium has many advantages in anesthetic practices, the best choice of a nondepolarizing neuromuscular blocking agent that can replace succinylcholine is rocuronium. However, it is reported that remifentanil with propofol might provide reliable intubating condition, even without a neuromuscular blocking agent; therefore, it might improve the intubating condition with cisatracurium. This study examined intubating conditions after administering rocuronium or cisatracurium in a rapid sequence induction with remifentanil-propofol. METHODS: Fifty two ASA physical status 1 or 2 adult patients scheduled for an elective surgery were enrolled in a randomized double-blinded trial. Anesthesia was induced in all patients with propofol 2.0 mg/kg and remifentanil 0.5 microgram/kg, administered over 60 seconds. Rocuronium 0.9 mg/kg (3 x ED95, R group, n = 23) or cisatracurium 0.15 mg/kg (3 x ED95, C group, n = 29) was administered after the induction sequence. Laryngoscopy was attempted when the anesthesiologist thought it was 90 seconds after drug administration and appropriate time for intubation. The examiner, another anesthesiologist, recorded the exact time to intubation and suppression of maximal T1 on TOF. The intubating condition was assessed by the first anesthesiologist, as excellent, good, poor or not possible. RESULTS: The best time to laryngoscopy was predicted by measuring TOF and was found to be significantly longer in the C group (197 +/- 53 s) than in the R group (102 +/- 49 s) (P value < 0.05). However, time to larygoscopy, intubating condition during the laryngoscopy, and hemodynamic changes after intubation was similar in both groups. CONCLUSIONS: Despite fundamentally slower onset time, cisatracurium can provide quite good intubating conditions, which were comparable to those achieved with equipotent doses of rocuronium, which is more expensive in anesthesia inducted with remifentanil and propofol.

Preanesthetic dexmedetomidine 1 microg/kg single infusion is a simple, easy, and economic adjuvant for general anesthesia / 대한마취과학회지

BACKGROUND: Dexmedetomidine is an alpha2-adrenoreceptor agonist with sedative, analgesic and anxiolytic effects, and it has more selective alpha2-adrenergic effect than clonidine. We evaluate the effect of preansethetic dexmedetomidine 1 microg/kg single infusion on sedation, hemodynamics, anesthetic consumption, and recovery profiles during anesthesia. METHODS: Forty-two female patients with American Society of Anesthesiologists physical status I or II undergoing gynecologic surgery with anticipated operation time of 2 h, were randomly assigned to receive dexmedetomidine 1 microg/kg (Dex group) or saline (control group) iv over 10 min before anesthetic induction. After tracheal intubation with propofol 2 mg/kg, cisatracurium 0.15 mg/kg iv, anesthesia was maintained with sevoflurane, O2 50%, N2O 50% around a BIS value of 40. RESULTS: After study drug infusion, BIS of Dex group was lower than that of control group (93.9 +/- 3.1 vs 51.5 +/- 5.2, P < 0.05). Mean arterial pressure (MAP) and heart rate (HR) after intubation were increased in control group, but did not change in Dex group. During maintenance, there was no difference in MAP between groups, but HR of Dex group was lower compared to that of control group. End-tidal concentration (2.0 +/- 0.5 vol% vs 1.4 +/- 0.3 vol%, P < 0.05) and total cumulative consumption of sevoflurane (34.6 +/- 3.8 ml vs 26.5 +/- 5.3 ml, P < 0.05) were lower in Dex group than in control group. Recovery profiles, modified Aldrete score, postoperative nausea vomiting, and visual analogue pain score were not significantly different between groups. CONCLUSIONS: Preanesthetic dexmetomidine 1 microg/kg single infusion is a simple, easy, and economic general anesthetic adjuvant that maintains stable hemodynamics and decrease anesthetic consumption without the change of recovery profiles.

Anaphylactic reactions after cisatracurium administration in two patients: a report of two cases / 대한마취과학회지

Cisatracurium was initially characterized to have no evident histamine-releasing potential with excellent cardiovascular stability. However, severe anaphylactic reactions to cisatracurium that resulted in bronchospasms and cardiovascular collapse have been reported worldwide. Two cases of severe anaphylactic reactions after the administration of cisatracurium are presented. The anesthetics used in both cases were lidocaine, midazolam, propofol (microemulsion propofol in the second case), remifentanil and cisatracurium. After the administration of these drugs, bronchospasm and hypotension manifested, leading to the diagnosis of anaphylaxis and appropriate treatment. Skin intradermal testing confirmed that both cases were due to immune-mediated anaphylaxis to cisatracurium, despite the fact that neither of the patients had been exposed to the allergen previously. The anaphylaxis may be due to cross-reactivity between neuromuscular blocking agents and substances with quaternary ammonium ions. Anesthesiologists should be aware that cisatracurium has the potential to trigger severe anaphylactic reactions via an immune-mediated mechanism.

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.

Effects on Intubating Conditions of Pretreatment with Remifentanil before Administration of Cisatracurium / 전남의대학술지

Cisatracurium provides superior hemodynamic stability with only minor release of histamine, and its metabolism via Hoffman elimination is independent of organ function. However, use of cisatracurium is limited because of reportedly slower onset and unsatisfactory intubating conditions. Many studies have shown that remifentanil might provide reliable intubating conditions; thus, we hypothesized that pretreatment with remifentanil before administration of cisatracurium might result in acceptable intubating conditions. Sixty healthy patients scheduled for elective surgery were enrolled and randomly divided into three groups: saline (Group I, n=20), remifentanil 0.5 microg/kg (Group II, n=20), and remifentanil 1.0 microg/kg (Group III, n=20). The anesthesia was induced with propofol 2.0 microg/kg given intravenously over 30 s followed by injection over 30 s of a different dose of remifentanil according to the study protocol. We examined the intubating condition by jaw relaxation, vocal cord state, and diaphragmatic response 90 s after administering cisatracurium. We also measured mean blood pressure, heart rate, and the onset time, which is the interval from the end of neuromuscular blocking agent administration until suppression of maximal T1 on a train-of four sequence. The mean values of the intubating condition after endotracheal intubation in Groups II and III were significantly lower than that in Group I (p<0.005), although the overall onset time of cisatracurium did not differ significantly between the three groups. Our results suggest that supplementation with remifentanil in an induction regimen with cisatracurium improves the quality of the intubating condition even though the onset time of cisatracurium is not shortened.

The effect of low dose ketamine and priming of cisatracurium on the intubating condition and onset time of cisatracurium / 대한마취과학회지

BACKGROUND: Both ketamine and priming may accelerate the onset time of neuromuscular blocking agents. We investigate the effect of low dose ketamine and cisatracurium priming on the intubating condition and onset time of cisatracurium. METHODS: After Institutional Review Board approval, 120 consecutive patients undergoing general anesthesia were randomly assigned to one of 4 groups. All patients were injected one of normal saline (group C), cisatracurium 0.01 mg/kg (group P), ketamine 0.5 mg/kg (group K) and combination of cisatracurium 0.01 mg/kg, and ketamine 0.5 mg/kg (group PK) diluted into a 5 ml solution, followed 3 minutes later by cisatracurium 0.15 mg/kg in group C and K, and 0.14 mg/kg cisatracurium in priming group. Onset time was recorded the electromyographical responses using single twitch and intubating conditions were evaluated at 60 seconds after cisatracurium administration. RESULTS: The mean onset time was most significantly accelerated in Group PK and was also significantly more accelerated in Group P and K compared with Group C (P < 0.008). It was 112.7 +/- 13.2, 91.4 +/- 17.9, 84.9 +/- 12.7 and 76.4 +/- 8.3 seconds in Group C, P, K, and PK, respectively. Intubating conditions were significantly improved in Group P, K and PK than Group C (P < 0.008). Especially, Group PK showed most significant improvement of intubating conditions. CONCLUSIONS: The combination of the low dose ketamine and cisatracurium priming accelerated the onset time and was improved the intubating conditions.

Effects on Intubating Conditions of Pretreatment with Remifentanil before Administration of Cisatracurium / 전남의대학술지

Cisatracurium provides superior hemodynamic stability with only minor release of histamine, and its metabolism via Hoffman elimination is independent of organ function. However, use of cisatracurium is limited because of reportedly slower onset and unsatisfactory intubating conditions. Many studies have shown that remifentanil might provide reliable intubating conditions; thus, we hypothesized that pretreatment with remifentanil before administration of cisatracurium might result in acceptable intubating conditions. Sixty healthy patients scheduled for elective surgery were enrolled and randomly divided into three groups: saline (Group I, n=20), remifentanil 0.5 microg/kg (Group II, n=20), and remifentanil 1.0 microg/kg (Group III, n=20). The anesthesia was induced with propofol 2.0 microg/kg given intravenously over 30 s followed by injection over 30 s of a different dose of remifentanil according to the study protocol. We examined the intubating condition by jaw relaxation, vocal cord state, and diaphragmatic response 90 s after administering cisatracurium. We also measured mean blood pressure, heart rate, and the onset time, which is the interval from the end of neuromuscular blocking agent administration until suppression of maximal T1 on a train-of four sequence. The mean values of the intubating condition after endotracheal intubation in Groups II and III were significantly lower than that in Group I (p<0.005), although the overall onset time of cisatracurium did not differ significantly between the three groups. Our results suggest that supplementation with remifentanil in an induction regimen with cisatracurium improves the quality of the intubating condition even though the onset time of cisatracurium is not shortened.

Effect of magnesium sulfate pretreatment on onset and recovery characteristics of cisatracurium / 대한마취과학회지

BACKGROUND: To determine how pretreatment with magnesium sulfate (MgSO4) potentiates neuromuscular blocking agents. We investigated how the onset and recovery characteristics of cisatracurium are changed by pretreatment with MgSO4. METHODS: After Institutional Review Board approval, a total of 48 ASA I and II patients were devided into 2 groups. Patients in each group received either the MgSO4 30 mg/kg (group M) in 0.9% normal saline (total volume 100 ml) or 0.9% normal saline (control group C) alone intravenously for 15 min before induction of anesthesia with propofol, remifentanil and cisatracurium 0.15 mg/kg. Anesthesia was maintained with propofol and remifentanil. Electromyographical responses were measured by train-of-four. Lag time, onset time, total recovery time, clinical duration, recovery index, and recovery time were measured. The mean arterial blood pressure, heart rate, and ionized magnesium were also measured. RESULTS: The lag time and onset time were significantly shorter in the MgSO4 group than the control group (P 0.05). Mean arterial pressure was more significantly increased in the MgSO4 group than in the control group at the time point immediately after the administration of MgSO4. Heart rate showed no significant changes in both groups. The concentrations of ionized magnesium were significantly more increased at the all time point (P < 0.05). CONCLUSIONS: MgSO4 results in about 29% shortening of onset time of cisatracurium (0.15 mg/kg) without prolongation on the recovery of neuromuscular block.

Effect of magnesium sulfate pretreatment on onset and recovery characteristics of cisatracurium / 대한마취과학회지

BACKGROUND: To determine how pretreatment with magnesium sulfate (MgSO4) potentiates neuromuscular blocking agents. We investigated how the onset and recovery characteristics of cisatracurium are changed by pretreatment with MgSO4. METHODS: After Institutional Review Board approval, a total of 48 ASA I and II patients were devided into 2 groups. Patients in each group received either the MgSO4 30 mg/kg (group M) in 0.9% normal saline (total volume 100 ml) or 0.9% normal saline (control group C) alone intravenously for 15 min before induction of anesthesia with propofol, remifentanil and cisatracurium 0.15 mg/kg. Anesthesia was maintained with propofol and remifentanil. Electromyographical responses were measured by train-of-four. Lag time, onset time, total recovery time, clinical duration, recovery index, and recovery time were measured. The mean arterial blood pressure, heart rate, and ionized magnesium were also measured. RESULTS: The lag time and onset time were significantly shorter in the MgSO4 group than the control group (P 0.05). Mean arterial pressure was more significantly increased in the MgSO4 group than in the control group at the time point immediately after the administration of MgSO4. Heart rate showed no significant changes in both groups. The concentrations of ionized magnesium were significantly more increased at the all time point (P < 0.05). CONCLUSIONS: MgSO4 results in about 29% shortening of onset time of cisatracurium (0.15 mg/kg) without prolongation on the recovery of neuromuscular block.

Asystole during manipulation with a curved-blade laryngoscope and tracheal intubation in patient with a history of syncope: A case report

Vagal reflex during manipulation with a curved-blade laryngoscope and tracheal intubation may result in severe bradycardia and even, asystole. Manipulation with laryngoscope and tracheal intubation leaded to bradycardia and asystole at a 47-year-old woman during induction of anesthesia with propofol, remifentanil and cisatracurium and sevoflurane inhalation. Withdrawal of laryngoscope and atropine 0.5 mg injection, her heart rate was recovered to normal sinus rhythm. Intubation at secondary trial was done with bradycardia and heart rate was returned to normal sinus rhythm soon. She had a history of syncope in interview after surgery and was examined tilt test to find of cause of syncope. Although the result of the test was negative, the bradycardia and asystole seemed to be caused by vagal reflex.

Es necesario utilizar relajantes musculares en infusión continua durante la anestesia en pacientes sometidos a cirugía cardíaca? / Is necessary to use infusion of muscle relaxants for anesthesia in patients undergoing cardiac surgery?

El trasplante renopancreático es el tratamiento de elección para el paciente diabético con insuficiencia renal crónica. En el Hospital Universitario, desde junio de 2002 a mayo de 2010 se han realizado 35 trasplantes renopancreáticos. Los receptores presentaban una larga evolución de su diabetes y del tratamiento dialítico, con alta incidencia de patología médica asociada. En todos los pacientes se realizó anestesia general y a la monitorización estándar se agregó: monitorización invasiva de la presión arterial y de la presión venosa central, así como monitorización paraclínica seriada. Se administró insulina en infusión continua para control de la glicemia. La duración promedio del procedimiento fue de 407,9 ± 76,4 min. La reposición intraoperatoria se realizó en base a cristaloides y coloides (4.665 ± 2.127 ml y 1.015 ± 492 ml respectivamente). En 21 pacientes (60%) se administraron glóbulos rojos (858 ± 502 ml). El balance promedio fue positivo: 1.430 ± 832 ml. Para mantener la estabilidad hemodinámica se utilizaron fármacos vasoactivos y aporte de volumen. Ocho pacientes (22,8%) presentaron hipotensión severa transitoria; 14 (40%) presentaron acidosis metabólica, ocho pacientes (22,8%) hipokaliemia leve y tres (8,5%) hipoglicemia. Veintitrés pacientes (65%) requirieron al menos una reintervención en la internación inicial. La mortalidad global fue de 11,4% (cuatro pacientes): 2,8% (un paciente) en las primeras 48 horas. Ocho pacientes (22,8%) presentaron insuficiencia renal desde el inicio del postoperatorio. Se perdieron 15 páncreas (42,8%); cinco de ellos (14,2%) en las primeras 48 horas. Actualmente sobreviven 31 pacientes (88%), 25 preservan la función renal (80,6%) y 20 la función pancreática (64,5%). Se reveló una alta incidencia de complicaciones anestésico-quirúrgicas precoces, las cuales tienen gran importancia sobre los resultados a corto y largo plazo.

Avaliação do bloqueio neuromuscular em crianças no momento da reversão do bloqueio e da retirada da cânula endotraqueal / Assessment of neuromuscular blockade in children at the time of block reversal and the removal of the endotracheal tube

JUSTIFICATIVA E OBJETIVOS: Estudos evidenciam a importância da monitoração da função neuromuscular na prevenção do bloqueio residual. No entanto, a maioria dos anestesistas em sua prática diária se abaliza em dados clínicos para avaliar a recuperação da função neuromuscular. O objetivo deste estudo foi avaliar o grau de bloqueio neuromuscular em crianças submetidas à anestesia geral no momento da reversão do bloqueio e da retirada da cânula endotraqueal. MÉTODO: Foram avaliadas crianças entre 3 meses e 12 anos, submetidas à anestesia geral com uso de atracúrio ou rocurônio. A monitoração foi iniciada no momento da reversão do bloqueio neuromuscular e/ou retirada da cânula endotraqueal. O anestesiologista não era informado sobre o valor de T4/T1; apenas era alertado quando o momento era inadequado para a retirada da cânula endotraqueal. Houve registro do grau de bloqueio neuromuscular desde o início da monitoração, bem como do intervalo para a recuperação da relação T4/T1 > 0,9, doses de bloqueador e neostigmina utilizadas, fração expirada do agente inalatório, duração da anestesia, temperatura central e periférica. RESULTADOS: O bloqueio neuromuscular foi revertido em 80 por cento das crianças no Grupo Rocurônio e 64,5 por cento no Grupo Atracúrio. A reversão foi incorreta em 45,8 por cento do Grupo Rocurônio e 25 por cento do Grupo Atracúrio. A incidência de T4/T1 < 0,9 no momento da retirada da cânula endotraqueal foi de 10 por cento em ambos os grupos. CONCLUSÕES: Na decisão de retirada da cânula endotraqueal, com base em critérios clínicos, 10 por cento das crianças apresentavam T4/T1 < 0,9, independentemente do bloqueador recebido. Um número considerável de pacientes teve o bloqueio neuromuscular revertido de maneira incorreta, quando o bloqueio ainda era profundo demais ou mesmo já estava recuperado.

BACKGROUND AND OBJECTIVES: Studies show the importance of monitoring neuromuscular function in preventing the residual block. However, most anesthesiologists in their daily practice base their evaluation of the recovery of neuromuscular function on clinical data. The aim of this study was to assess the degree of neuromuscular blockade in children undergoing general anesthesia at the time of block reversal and the removal of the endotracheal tube. METHOD: We evaluated children between 3 months and 12 years of age undergoing general anesthesia with the use of atracurium or rocuronium. Monitoring was initiated at the time of reversal of neuromuscular blockade and/or removal of the endotracheal tube. The anesthesiologist was not informed about the T4/T1 value; he/she was only alerted when the time was inadequate for the removal of the endotracheal tube. Since the start of the monitoring process, the degree of neuromuscular blockade was registered, as well as the interval of recovery of the T4/T1 > 0,9 ratio, the doses of neostigmine and blocker used, the expired fraction of the inhalational agent, the duration of the anesthesia, and core and peripheral temperatures. RESULTS: Neuromuscular blockade was reversed in 80 percent of the children of the Rocuronium Group and in 64.5 percent of the Atracurium Group. The reversal was incorrect in 45.8 percent of the Rocuronium Group and in 25 percent of the Atracurium Group. The incidence of T4/T1 < 0.9 at the time of the removal of the endotracheal tube was 10 percent in both groups. CONCLUSIONS: When deciding to remove the endotracheal tube based on clinical criteria, 10 percent of children had T4/T1 < 0.9 regardless the blocker received. A considerable number of patients had the neuromuscular blockade incorrectly reversed when the blockade was still too deep or even already recovered.

JUSTIFICATIVA Y OBJETIVOS: Algunos estudios demuestran la importancia de la monitorización de la función neuromuscular en la prevención del bloqueo residual. Sin embargo, la mayoría de los anestesiólogos en su práctica diaria, se basa en datos clínicos para evaluar la recuperación de la función neuromuscular. El objetivo de este estudio fue evaluar el grado de bloqueo neuromuscular en niños sometidos a la anestesia general, en el momento de la reversión del bloqueo y de la retirada de la cánula endotraqueal. MÉTODO: Se evaluaron niños entre 3 meses y 12 años, sometidos a la anestesia general con el uso de atracurio o rocuronio. La monitorización se inició al momento de la reversión del bloqueo neuromuscular y/o retirada de la cánula endotraqueal. El anestesiólogo no conocía el valor de T4/T1; apenas se le avisaba cuando el momento no era el adecuado para la retirada de la cánula endotraqueal. Se registró el grado de bloqueo neuromuscular desde el inicio de la monitorización, como también el intervalo para la recuperación de la relación T4/T1 < 0,9, dosis de bloqueante y neostigmina utilizadas, fracción expirada del agente inhalatorio, duración de la anestesia, temperatura central y periférica. RESULTADOS: El bloqueo neuromuscular fue revertido en un 80 por ciento de los niños en el Grupo Rocuronio y en un 64,5 por ciento en el Grupo Atracurio. La reversión fue incorrecta en un 45,8 por ciento del Grupo Rocuronio y en un 25 por ciento del Grupo Atracurio. La incidencia de T4/T1 < 0,9 al momento de la retirada de la cánula endotraqueal fue de un 10 por ciento en los dos grupos. CONCLUSIONES: En la toma de decisión de la retirada de la cánula endotraqueal, en base a los criterios clínicos, el 10 por ciento de los niños presentaron T4/T1 < 0,9, independientemente del bloqueante recibido. Un número considerable de pacientes tuvo el bloqueo neuromuscular revertido de manera incorrecta, cuando el bloqueo todavía era muy profundo...