Survey of postoperative residual curarization, acute respiratory events and approach of anesthesiologists / Pesquisa de curarização residual no pós-operatório, eventos respiratórios agudos e abordagem de anestesiologistas

BACKGROUND AND OBJECTIVES: residual paralysis following the use of neuromuscular blocking drugs (NMBDs) without neuromuscular monitoring remains a clinical problem, even when NMBDs are used. This study surveys postoperative residual curarization and critical respiratory events in the recovery room, as well as the clinical approach to PORC of anesthesiologists in our institution. METHODS: This observational study included 415 patients who received general anesthesia with intermediate-acting NMBDs. Anesthesia was maintained by non-participating anesthesiologists who were blinded to the study. Neuromuscular monitoring was performed upon arrival in the recovery room. A CRE was defined as requiring airway support, peripheral oxygen saturation <90% and 90-93% despite receiving 3 L/min nasal O2, respiratory rate >20 breaths/min, accessory muscle usage, difficulty with swallowing or speaking, and requiring reintubation. The clinical approach of our anesthesiologists toward reversal agents was examined using an 8-question mini-survey shortly after the study. RESULTS: The incidence of PORC was 43% (n = 179) for TOFR <0.9, and 15% (n = 61) for TOFR <0.7. The incidence of TOFR <0.9 was significantly higher in women, in those with ASA physical status 3, and with anesthesia of short duration (p < 0.05). In addition, 66% (n = 272) of the 415 patients arriving at the recovery room had received neostigmine. A TOFR <0.9 was found in 46% (n = 126) of the patients receiving neostigmine. CONCLUSIONS: When routine objective neuromuscular monitoring is not available, PORC remains a clinical problem despite the use of NMBDs. The timing and optimal antagonism of the neuromuscular blockade, and routine objective neuromuscular monitoring is recommended to enhance patient safety.

JUSTIFICATIVA E OBJETIVOS: A paralisia residual após o uso de bloqueadores neuromusculares (BNMs) sem monitoração neuromuscular continua sendo um problema clínico, mesmo quando BNMs são usados. Este estudo pesquisou a curarização residual pós-operatória e os eventos respiratórios críticos em sala de recuperação, bem como a abordagem clínica da CRPO feita pelos anestesiologistas em nossa instituição. MÉTODOS: Este estudo observacional incluiu 415 pacientes que receberam anestesia geral com BNMs de ação intermediária. A manutenção da anestesia foi feita por anestesiologistas não participantes, "cegos" para o estudo. A monitoração neuromuscular foi realizada no momento da chegada à sala de recuperação. Um ERC foi definido como necessidade de suporte ventilatório; saturação periférica de oxigênio <90% e 90-93%, a despeito de receber 3 L/min de O2 via cânula nasal; frequência respiratória >20 bpm; uso de musculatura acessória; dificuldade de engolir ou falar e necessidade de reintubação. A abordagem clínica de nossos anestesiologistas, em relação aos agentes de reversão, foi avaliada usando um miniquestionário de oito perguntas logo após o estudo. RESULTADOS: A incidência de CRPO foi de 43% (n = 179) para a SQE <0 e 15% (n = 61) para a SQE <0,7. A incidência de SQE <0,9 foi significativamente maior em mulheres, pacientes com estado físico ASA III e com anestesia de curta duração (p < 0,05). Além disso, 66% (n = 272) dos 415 pacientes que chegam à sala de recuperação haviam recebido neostigmina. Uma SQE <0,9 foi encontrada em 46% (n = 126) dos pacientes que receberam neostigmina. CONCLUSÃO: Quando a monitoração neuromuscular objetiva de rotina não está disponível, a CRPO continua sendo um problema clínico, a despeito do uso de BNMs. O momento e o antagonismo ideais do bloqueio neuromuscular e a monitoração neuromuscular objetiva de rotina são recomendados para aumentar a segurança do paciente.

Comparison of Post-operative Analgesic Efficacy of Caudal Epidural Bupivacaine Versus Bupivacaine and Neostigmine Combination in Infraumbilical Surgeries in Children.

Spinal muscarinic M1 receptors are believed to be involved in the analgesic properties of spinal neostigmine. Aims were to determine the effect of adding neostigmine to bupivacaine on the duration of caudal analgesia as compared with caudal bupivacaine alone, to determine the need for rescue analgesics in the post-operative period. Material and Methods: 50 patients of ASA Grade I and II, aged between 2 to 8 years, of either sex underwent infraumbilical surgeries. Post-operative caudal epidural analgesia was activated after completion of the surgery and before recovery from anaesthesia Group-A (n=25) received caudal epidural injection of preservative free bupivacaine 0.125%. 2 mg/kg, Group-B (n=25) received both preservative free bupivacaine 0.125% and neostigmine 2μg/kg. Results and Analysis: After extubation children were evaluated for pain using the CHEOPS pain scale, shows no significant difference between the two study groups at 2 post-operative hours. Group B patients required less rescue analgesic than Group A patients in 24 hrs postoperative period. Conclusion: Addition of neostigmine to bupivacaine in caudal epidural bupivacaine prolonged the duration of caudal analgesia in the post-operative period compared to caudal bupivacaine alone.

The use of rocuronium in giant Amazon turtle Podocnemis expansa (Schweigger, 1812) (Testudines, Podocnemididae) / Uso do rocurônio em tartaruga da Amazônia Podocnemis expansa (Schweigger, 1812) (Testudines, Podocnemididae)

PURPOSE: To determine whether rocuronium would provide safe, short-term immobilization in Podocnemis expansa. METHODS: Twenty P. expansa, weighing on average 1.59 ± 0.28 kg, were subjected to two protocols: G1 0.25 mg/kg IM of rocuronium and 0.07 mg/kg IM of neostigmine, while G2 received 0.50 mg/kg IM of rocuronium and 0.07 mg/kg IM of neostigmine. The drugs were applied, respectively, in the left and right thoracic members. Assessments were made of the anesthetic parameters of respiratory frequency, heartbeat, righting reflex, cloacal relaxation, palpebral and pupilar reflexes, easy handling, muscle relaxation, locomotion, response to pain stimuli in the right thoracic members, pelvic members and tail, ambient humidity and temperature. RESULTS: They were not found statistical differences between the dosages for the majority of the assessments. G1 was as efficient as G2. A consistent neuromuscular blockade effect was recorded 12 ± 4.21 minutes in G1 and G2. All the animals were recovered in 150 minutes. CONCLUSIONS: Administration of rocuronium at dose of 0.25 to 0.5 mg/kg IM is a safe and effective adjunct to clinical proceedings or pre-anesthetics in P. expansa. Because rocuronium does not provide any analgesic or sedative effects, the duration of neuromuscular blockade without anesthesia should be minimized to avoid undue stress.

OBJETIVO: Determinar se o rocurônio promove imobilização segura e de curta duração em Podocnemis expansa. MÉTODOS: Vinte P. expansa com média de peso 1,59 ± 0,28 kg, foram submetidas a dois protocolos: G1 recebeu rocurônio 0,25 mg/kg IM e neostigmina 0,07 mg/kg IM enquanto G2 rocurônio 0,50 mg/kg IM e neostigmina 0,07 mg/kg IM, aplicados no membro torácico esquerdo e direito, respectivamente. Observaram-se os parâmetros anestésicos: freqüência respiratória e cardíaca, reflexo de endireitamento, relaxamento do esfíncter da cloaca, reflexo palpebral e pupilar, facilidade de manipulação, relaxamento muscular, locomoção, resposta aos estímulos dolorosos no membro torácico direito, nos membros pelvinos e na cauda, temperatura e umidade ambiental. RESULTADOS: Não foram encontradas diferenças estatísticas entre as doses para a maioria dos parâmetros e o G1 foi tão eficiente quanto o G2. Um bloqueio neuromuscular consistente foi observado aos 12 ± 4,21 minutos tanto no G1 como no G2. A recuperação de todos os animais ocorreu em até 150 minutos. CONCLUSÕES: Administração de rocurônio nas doses 0,25 e 0,50 mg/kg IM é segura e efetiva para os procedimentos clínicos ou pré-anestésicos em P. expansa. Como o rocurônio não produz efeitos sedativos ou analgésicos, a duração do bloqueio neuromuscular sem anestesia deverá ser minimizado para evitar estresse.

Efeitos da metadona ou do neostigmine, associados à lidocaína administrados pela via epidural em cães / Effects of methadone or neostigmine in combination with lidocaine for epidural anesthesia in dogs

Seis cães adultos, de raças e sexos variados, com peso de 13,3±3,4kg (média±DP), foram utilizados no estudo. Os animais foram tranqüilizados com acepromazina (0,1mg/kg, IV) e, após 30 minutos, foram aleatoriamente submetidos à anestesia epidural com um dos seguintes tratamentos: lidocaína 2 por cento 0,25ml/kg (controle); neostigmine 0,01mg/kg+lidocaína (NEO); metadona 0,3mg/kg+lidocaína (MET). Todos os animais foram submetidos aos três tratamentos com intervalo mínimo de uma semana. Foram mensuradas as freqüências cardíaca (FC) e respiratória (FR), a pressão arterial sistólica (PAS), o tempo para a perda do reflexo interdigital, a duração e a altura do bloqueio sensitivo, durante um período de 90 minutos. Não houve diferença significativa entre os tratamentos nos valores de FC, PAS e FR, bem como na duração do bloqueio sensitivo e no tempo para a perda do reflexo interdigital. No grupo MET, houve diminuição de FC dos 30 aos 90 minutos em relação ao valor basal. Bloqueio sensitivo mais cranial também foi observado em MET. A associação de neostigmine ou metadona não prolongou o período hábil de anestesia epidural produzido pela lidocaína em cães. A metadona, mas não o neostigmine, parece estender mais cranialmente o bloqueio epidural pela lidocaína.

Six mature mongrel dogs of both genders, weighing 13.3±3.4kg (mean±SD) were used in the present research. Thirty minutes after premedication with intravenous acepromazine (0.1mg/kg, IV), dogs were randomly assigned to receive epidural administration of one of following three treatments: 2 percent lidocaine 0.25ml/kg (control), or neostigmine 0.01mg/kg plus lidocaine (NEO), or methadone 0.3mg/kg plus lidocaine (MET). All dogs received all treatments in a cross-over design with at least one-week interval. Heart rate (HR), respiratory rate (RR), systolic arterial pressure (SAP), time to loss of pedal withdrawal reflex, duration of epidural anesthesia, and cranial spread of epidural anesthesia were evaluated for 90 minutes. No differences among treatments in HR, RR, SAP, duration of anesthesia, and time to loss of pedal withdrawal reflex were found. In MET, HR decreased from 30 to 90 minutes compared to baseline and there was a higher cranial spread of epidural anesthesia than in controls and NEO animals. Neostigmine or methadone did not prolong epidural anesthesia with lidocaine in dogs. Methadone, but not neostigmine, appeared to result in more cranial spread of epidural anesthesia with lidocaine.

Neostigmine does not prolong the duration of analgesia produced by caudal bupivacaine in children undergoing urethroplasty.

CONTEXT: Neostigmine extends the duration of analgesia produced by caudal bupivacaine in children. AIMS: To study the effect of different doses of caudal neostigmine on the duration of postoperative analgesia. SETTINGS AND DESIGN: A randomized, double-blind study was conducted in 120 boys aged 1-12 years undergoing urethroplasty under combined general and caudal anesthesia. MATERIALS AND METHODS: Children were administered 1.875 mg/kg bupivacaine alone (Group B) or with 2, 3 or 4 microg/kg of neostigmine (groups BN 2, BN 3 or BN 4 respectively) as caudal drug (0.75 ml/kg). Children with a pain score of 4 or more (OPS and NRS) postoperatively were administered rescue analgesic. Time to first analgesic and the number of analgesic doses administered in the 24h were recorded. STATISTICAL ANALYSIS: Parametric data were analyzed using ANOVA. Kaplan-Meier survival curves for the time to first analgesic administration were plotted and compared using log rank analysis. Chi-square test was used to analyze the incidence data. RESULTS: The median [IQR] time to first analgesic in Group B (540 [240-1441] min) was similar to that in Groups BN 2 (450 [240-720]), BN 3 (600 [360-1020]) and BN 4 (990 [420-1441]). Significantly more patients in Groups B (9 [34.6%]) and BN 4 (13 [44.8%]) required no supplemental analgesic for 24h than those in Groups BN 2 and BN 3 (4 [13.8%] and 4 [13.3%]). The number of analgesic doses required in 24h in the four groups was similar. CONCLUSION: Addition of neostigmine to 1.875 mg/kg of caudal bupivacaine did not prolong the analgesia following urethroplasty in children.

Analgesic efficacy and safety of intrathecal neostigmine in patients undergoing total knee replacement

In recent human and animal studies, intrathecal administration of various doses of neostigmine produces analgesia without neurotoxicity. Intrathecal neosrtigmine has been used as an adjunct to intrathecal local anaesthetic or opioid to prolong regional analgesia and improve haemodynamic stability, with variable results. The present study was designed to compare the effects of the addition of IT neostigmine or IT morphine on the characteristics of spinal anesthesia with bupivacaine and to assess their postoperative analgesic efficacy and safety in patients undergoing total knee replacement surgery under spinal anesthesia. Sixty patients scheduled for elective total knee replacement under spinal anesthesia were randomly divided into three equal groups which received IT 0.5% hyperbaric bupivacaine 15 mg with either normal saline 0.5 mL, neostigmine 50 micro g. or morphine 300 micro g. The maximal level of sensory block, duration of analgesia, time to use of rescue analgesics, the overall 24-hr and four-hour interval visual analogue scale [VAS] pain score, and the incidence of adverse effects were recorded for 24 hr after administration. There was no significant difference in maximal level of sensory block among the three groups. The morphine group had a later onset of postsurgical pain and longer time to first rescue analgesics than the neostigmine group [P <0.05]. Overall 24-hr VAS pain scores were significantly higher in the saline group vs the morphine and neostigmine groups [P <0.05]. Motor block lasted significantly longer in the neostigmine group than in the morphine and saline groups [P <0.05]. The incidence of adverse effects was similar in the neostigmine and morphine groups except for pruritus [70%] occurring more frequently in the morphine group than in the neostigmine and saline groups [0%; P <0.05]. Overall satisfaction rates were better in the neostigmine group than in the morphine and saline groups [P <0.05]. IT neostigmine 50 pg produced postoperative analgesia lasting about seven hours with fewer side effects and better satisfaction ratings than IT morphine 300 micro g

Neostigmine intrathecal and transdermal nitroglycerine augment intrathecal bupivacaine-fentanyl postoperative analgesia following lower limb surgery

Sixty patients were scheduled for lower limb operations. Their age ranged from 24 to 49 years [mean 41.7 +/- 6.4]. Patients were divided into four groups each group included 15 patients. All patients were given intrathecal bupivacaine - fentanyl, plus group [I] was given [non transdermal nitroglycerine patch] as placebo, group [II] transdermal nitroglycerine patch 5mg /24 hours, group [III] intrathecal neostigmine 10 ug and [non transdermal nitroglycerine patch] as placebo and group [IV] transdermal nitroglycerine patch 5mg /24 hours plus intrathecal neostigmine 10 ug. All groups were assessed for intraoperative and a period of postoperative 24 hours for vital parameters, postoperative analgesia and duration of effective analgesia as time from intrathecal drug administration to the patients first requested for analgesic medication, adverse side effects and total dose to control pain in 24 hours postoperative. Results of this study revealed multiple drug combination may be useful in extending postoperative analgesia of spinal bupivacaine - fentanyl associated with transdermal nitroglycerine patch and neostigmine intrathecal .Suggesting that transdermal nitroglycerine patch and neostigmine may enhance each other's antinociceptive effects at the dose studied

Synergistic Effects Between Intrathecal Clonidine and Neostigmine in the Formalin Test

Spinal alpha-2 adrenoceptors and cholinergic receptors are involved in the regulation of acute nociception and the facilitated processing. The aim of this study was to examine the pharmacological effect of an intrathecal alpha-2 agonist and a cholinesterase inhibitor on the facilitated pain model induced by formalin injection and to determine the nature of drug interaction using an isobolographic analysis. Both intrathecal clonidine and neostigmine dose-dependently suppressed the flinching during phase 1 and phase 2. Intrathecal pretreatment with atropine reversed the antinociceptive effects of clonidine and neostigmine in both phases. Pretreatment with intrathecal yohimbine attenuated the effect of clonidine. The antinociception of clonidine and neostigmine was not reversed by mecamylamine. Isobolographic analysis showed that intrathecal clonidine and neostigmine acted synergistically in both phase 1 and 2. Intrathecal pretreatment with atropine and yohimbine antagonized the effect of the mixture of clonidine and neostigmine in both phases, but no antagonism was observed with mecamylamine pretreatment. These data indicate that spinal clonidine and neostigmine are effective to counteract the facilitated state evoked formalin stimulus, and these two drugs interact in a synergistic fashion. In addition, the analgesic action of intrathecal clonidine is mediated by spinal muscarinic receptors as well as alpha-2 adrenoceptors.

Reversión de la relajación neuromuscular y medios de monitoreo / Reversal of neuromuscular blockade and monitoring

La comprensión de la farmacocinética y la farmacodinamia de los relajantes musculares y el empleo del monitoreo de la transmisión neuromuscular, son elementos esenciales en la reversión del bloqueo neuromuscular. Esa reversión es adecuada cuando el registro de las respuestas musculares al Tren de Cuatro es superior al 70-80 por ciento, mientras que los demás métodos tienen menor especificidad. Entre los medios con registro disponible (fuerza, electromiograma, aceleración), el más práctico para el monitoreo es la acelerometría isotónica. Frente a la ausencia de métodos de registro, se impone la Estimulación de Doble Ráfaga, aunque su especificidad es del 96 por ciento. Antes de intentar la reversión farmacológica, el raciocinio clínico pronóstico de la función neuromuscular debe incluir los siguientes items: profundidad previa del bloqueo, posibilidad de interacciones farmacológicas, duración de la administración del relajante, mecanismo de finalización del efecto relajante según sea el agente usado, método empleado en el mantenimiento de la relajación, balance térmico y ácido-base del paciente, y su condición física. Si el nivel plasmático del relajante es alto, se puede obtener una reversión transitoria inyectando neostigmina, pero deben tomarse los cuidados necesarios en la sala de recuperación para reconocer y tratar adecuadamente una recurrencia del bloqueo neuromuscular.

Miastenia gravis y embarazo / Myastenia gravis and pregnancy

La Miastenia gravis afecta a mujeres jóvenes en edad reproductiva. El conocimiento acerca de los efectos potenciales del embarazo y el uso de drogas inmunosupresoras en esta patología es limitado. Por otro lado, no existen factores predictivos que identifiquen a las madres en riesgo de exacerbaciones periparto y de los neonatos que presentarán Miastenia gravis neonatal. Presentamos a continuación el caso clínico de una paciente, la cual cursa dos embarazos en tratamiento de esta patología. Se comenta el manejo, el tipo de parto el período neonatal y postparto

Reversäo do bloqueio neurosmuscular induzido pelo cisatracúrio com diferentes doses de neostigmina / Reversal of cisatracurium neuromuscular block with different doses of neostigmine

Justificativa e objetivos - A neostigmina em doses de 0,04 a 0,06mg.kg-1 antagoniza efetivamente o bloqueio neuromuscular induzido pelo cisatracúrio. Este estudo avaliou o padräo de recuperaçäo do bloqueio neuromuscular induzido pelo cisatracúrio, com três doses diferentes desses anticolinesterásico. Método - participaram do estudo 56 pacientes adultos (M/F:22/34), estado físico ASA I e II, com idade de 40,18 ñ 12,7 anos, alocados por sorteio prévio em quatro grupos. Todos os pacientes receberam cisatracúrio na dose de 0,15 mg.kg-1, por via venosa, logo, após a induçäo da anestesia. A resposta eletromiográfica foi medida em intervalos de 10 segundos. Quando T1 apresentou recuperaçäo de 10 por cento em relaçäo ao controle, neostigmina foi administrada nas doses de 0,02 (G1;n=16), 0,03 (G2;n=15) e 0,05 (G3;n=14)mg.kg-1. O grupo G4 näo recebeu neostigmina. A relaçäo T4/T1 foi anotada a intervalos de 1 minuto nos 20 minutos subsequentes. Resultados - no período entre 0 e 4 minutos, näo houve diferença significativa entre as doses, quanto à relaçäo T4/T1. Entre o 5º e o 14º minuto, o grupo G3 apresentou relaçöes T4/T1 médias maiores que o grupo G1, em todos os momentos e maiores que o grupo G2 nos minutos 5, 7, 9 e 10. A partir do 15º minuto näo houve diferença estatisticamente significativa entre os valores médios da relaçäo T4/T1 entre os grupos que receberam neostigmina. Os valores médios de T4/T1 foram significativamente menores no grupo G4, a partir do 4º minuto. O percentual de pacientes que apresentaram relaçöes T4/T1 maior ou igual 0,9 ao término do período de observaçäo (20ºminuto) no grupo G3 (92,85 por cento) foi significativamente maior do que nos grupos G1 (56,25 por cento) e G2 (46,66 por cento). No grupo G4, nenhum paciente apresentou relaçäo T4/T1 igual ou superior a 0,9, diferindo significativamente dos outros grupos. Conclusöes - embora a dose de 0,05mg.kg-1 acelere a recuperaçäo da relaçäo T4/T1 até 0,7, näo difere das doses de 0,02 e 0,03mg.kg-1. Apesar disto, um percentual significativamente maior de pacientes apresentou relaçäo T4/T1 igual ou seperior a 0,9, quando a dose de neostigmina foi de 0,05 mg.kg-1, em comparaçäo com as doses menores

Analgesia postoperatoria con y sin neostigmina espinal / Postoperative analgesia with and without the addition of spinal neostigmine

Se realizó un estudio anestésico prospectivo, longitudinal y compartivo en 30 pacientes del sexo femenino a quienes se les practicó artroplastía de la cadera o de la rodilla. Se clasificaron en grupos de 15 integrantes cada uno; el grupo A, de estudio se manejó con 15 mg de bupivacaína al 0.5 por ciento con 50 µg de metilsulfato de neostigmina por vía intratecal, mientras que al lote control se les administró por la misma vía, 15 mg de bupivacaína al 0.5 por ciento con 1 ml de glucosa al 5 por ciento. Se observó analgesia más significativa y de mayor duración en el grupo tratado con neostigmina, sin embargo, presentaron mayor frecuencia de náusea, vómito, bradicardia e hipotensión arterial

Estudo comparativo entre modelo de analgesia com morfina controlada pelo paciete e com cetoprofeno e dipirona no pós-operatório de colecistectomia / Patient-controlled analgesia with morphine versus treatment with metamizol and ketoprofen in patients submitted to cholecystectomy

Justificativa e objetivos - considerando que em nosso serviço, na maioria das vezes os cuidados no tratamento da dor fica a cargo do médico residente, näo existindo uniformidade na conduta, resolvemos fazer um estudo envolvendo o tratamento aplicado na rotina do serviço. Este estudo visa comparar o modelo de analgesia controlada pelo paciente com o tratamento com cetoprofeno e dipirona em pacientes colecistectomozadas. Método - as pacientes foram divididas em dois grupos: grupo PCA - tratamento com morfina por via venosa em bomba de PCA; e grupo Controle - tratamento com cetoprofeno e dipirona. A bomba de PCA permitia doses intermitentes de morfina (1 mg), sendo que o intervalo mínimo permitido entre as doses era de 8 minutos. Foram anotadas em ambos os grupos: pressäo arterial, frequência respiratória, frequência cardíaca, escala de sedaçäo, escala visual analógica para dor em repouso e ao movimento, incidência de náusea e vômito e satisfaçäo com relaçäo a analgesia pós-operatória. Resultados - näo houve diferença significativa entre os dois grupos no que concerne a idade, frequência respiratória, peso, duraçäo da cirurgia e quantidade de fentanil utilizada intra-operatoriamente. A incidência de náusea e vômito foi semelhante em ambos os grupos. O grupo PCA apresentou menor intensidade (diferença significativa) de dor na quarta hora do estudo em relaçäo ao grupo controle. Conclusöes - as complicaçöes mais frequentes com o uso de opióides näo foram significativas. A autonomia do paciente confere maior satisfaçäo com o método de analgesia pela PCA

Do we need anti snake venom (ASV) for management of elapid ophitoxaemia.

Twelve patients of elapid ophitoxaemia presented with neuromuscular paralytic features were given anticholinesterase (Neostigmine) in recommended dosage. In four of these patients, despite neuromuscular paralysis, no ASV was used. All these four patients survived. In eight patients, ASV was used; in three of whom it used in doses less than 50 units, yet patients survived. Of the remaining five, despite use of ASV in higher doses (more than 50 units), two succumbed to death. Eight patients required ventilatory support. Hence, in absence of any definite role of ASV in management of elapid ophitoxaemia (snake bite), use of anticholinesterase drugs alone, with good supportive care and prevention of likely complications, can result in satisfactory outcome.

Acción anticolinérgica de clonidina sobre los efectos cardiovasculares de la estimulación colinérgica central / Anticholinergic action of clonidine on cardiovascular effects of the central cholinergic estimulation

Fue realizado un estudio acerca de la acción anticolinérgica del agonista adrenérgico alfa2 clonidina sobre las respuestas cardiovasculares a la inyección i.c.v. del agente anticolinesterásico cuaternario neostigmina a ratas conscientes. E1 agente colinérgico neostigmina (0,1-1 mug i.c.v.) indujo en las ratas una respuesta presora y bradicardia en forma dependiente de la dosis. Clonidina, a la dosis de 10 mug. Kg(-1) (i.v.) y administrado 30 min antes del anticolinesterásico, no modificó el efecto presor de neostigmina (0,1-1 mug i.c.v.) pero previno la bradicardia. Por otra parte, la administración i.c.v. de clonidina (3 mug), inyctada 15 min. antes de neostigmina, sólo previno el efecto bradicardizante del anticolinesterásico (0,3 mug i.c.v.) pero la acción presora central de la droga. Estos resultados sostienen la idea de que la clonidina tiene una acción anticolinérgica en la rata. Sin embargo, la prevención por clonidina de la bradicardia inducida por estimulación central sugiere una interacción diferente colinérgica-adrenérgica según la respuesta cardiovascular originada por la administración central de agentes colinérgicos. .

Comparative study on reversal of neuromuscular blockade induced by D-tubocurarine, pancuronium, gallamine and atracurium using neostigmine

A sample of 120 patients of both sexes of class 1 ASA classification scheduled for elective surgery were divided into four equal groups, each of 30 patients according to the neuromuscular [NM] blocker used either tubocurarine, pancuronium, gallamine or atracurium, respectively. After the initial dose of muscle relaxant the incremental doses of muscle relaxant and the dose of neostigmine were given to patients judged by nerve stimulator. It was found that the more the duration of the operation, the more the need to muscle relaxant and the more neostigmine requirement for reversal. The degree of NM blockade at which reversal can be initiated is a far more important than the total dose of relaxant administered. Neostigmine 2.5 mg was the maximum dose for reversal of severe degree of neuromuscular block. Atracurium at lesser degrees of block required less neostigmine than other muscle relaxants