Combination of clonidine-bupivacaine in caudal epidural anesthesia for hypospadias surgery in children: prospective, randomized, blind study / Associação clonidina-bupivacaína na anestesia peridural caudal para cirurgia de hipospádia em crianças: estudo prospectivo, randomizado, encoberto

Abstract Background and objectives: The combination of clonidine with local anesthetic administered for epidural anesthesia via caudal route seems to improve the quality of postoperative analgesia, but with conflicting results. This study compared the postoperative analgesia of three different doses of clonidine combined with bupivacaine in caudal epidural anesthesia in children undergoing hypospadias repair. Methods: Eighty children aged 1-10 years, candidates for surgical repair of hypospadias, were randomly divided into four groups of 20 patients to receive general anesthesia combined with caudal epidural anesthesia with bupivacaine 0.165% alone or in combination with 1, 2 or 3 µg.kg- 1 of clonidine. The primary outcome was morphine consumption in the first 24 h postoperatively. Mean arterial pressure, heart rate, end-tidal concentration of sevoflurane, time to awakening, pain severity (FLACC scale), level of sedation (RAMSAY), duration of analgesia, and occurrence of adverse effects were also compared. Results: Intraoperatively, there was no difference between groups regarding mean arterial pressure, heart rate, end-tidal concentration of sevoflurane, and time to awakening. Postoperative morphine consumption and pain severity were similar between groups, but the group receiving clonidine (3 µg.kg-1) had lower heart rate and higher sedation level than the group receiving bupivacaine alone. Conclusions: The combination of clonidine at doses of 1, 2 or 3 µg.kg-1 with bupivacaine 0.16% via caudal epidural route did not alter the consumption of morphine in the early postoperative period of children undergoing hypospadias repair.

Resumo Justificativa e objetivos: A associação de clonidina ao anestésico local administrado por via peridural caudal parece melhorar a qualidade da analgesia pós-operatória, mas com resultados conflitantes. Este estudo comparou a analgesia pós-operatória de três diferentes doses de clonidina associada à bupivacaína na anestesia peridural caudal em crianças submetidas à correção de hipospádia. Método: Oitenta crianças entre um e dez anos, candidatas à correção cirúrgica de hipospádia, foram divididas, aleatoriamente, em quatro grupos de 20 pacientes para receber anestesia geral associada à anestesia peridural caudal com bupivacaína 0,166% isolada ou associada a 1, 2 ou 3 µg.Kg-1 de clonidina. Como desfecho principal avaliou-se o consumo de morfina nas primeiras 24 horas de pós-operatório. Compararam-se também pressão arterial média, frequência cardíaca, concentração expirada de sevoflurano, tempo de despertar da anestesia, intensidade da dor pela escala FLACC, nível de sedação (Ramsay), tempo de duração da analgesia e ocorrência de efeitos adversos. Resultados: No transoperatório, não houve diferença entre os grupos quanto à pressão arterial média, frequência cardíaca, concentração expirada de sevoflurano e ao tempo de despertar. No pós-operatório, o consumo de morfina e a intensidade da dor foram similares entre os grupos, mas o grupo que recebeu 3 µg.Kg-1 de clonidina apresentou menor frequência cardíaca e maior sedação do que o grupo que recebeu somente bupivacaína. Conclusões: A associação de clonidina nas doses de 1, 2 ou 3 µg.Kg-1 à bupivacaína 0,166% por via peridural caudal não alterou o consumo de morfina no pós-operatório imediato de crianças submetidas à correção de hipospádia.

[Combination of clonidine-bupivacaine in caudal epidural anesthesia for hypospadias surgery in children: prospective, randomized, blind study]. / Associação clonidina­bupivacaína na anestesia peridural caudal para cirurgia de hipospádia em crianças: estudo prospectivo, randomizado, encoberto.

BACKGROUND AND OBJECTIVES: The combination of clonidine with local anesthetic administered for epidural anesthesia via caudal route seems to improve the quality of postoperative analgesia, but with conflicting results. This study compared the postoperative analgesia of three different doses of clonidine combined with bupivacaine in caudal epidural anesthesia in children undergoing hypospadias repair. METHODS: Eighty children aged 1 to 10 years, candidates for surgical repair of hypospadias, were randomly divided into four groups of 20 patients to receive general anesthesia combined with caudal epidural anesthesia with bupivacaine 0.165% alone or in combination with 1, 2 or 3µg.kg-1 of clonidine. The primary outcome was morphine consumption in the first 24hours postoperatively. Mean arterial pressure, heart rate, end-tidal concentration of sevoflurane, time to awakening, pain severity (FLACC scale), level of sedation (RAMSAY), duration of analgesia, and occurrence of adverse effects were also compared. RESULTS: Intraoperatively, there was no difference between groups regarding mean arterial pressure, heart rate, end-tidal concentration of sevoflurane, and time to awakening. Postoperative morphine consumption and pain severity were similar between groups, but the group receiving clonidine (3µg.kg-1) had lower heart rate and higher sedation level than the group receiving bupivacaine alone. CONCLUSIONS: The combination of clonidine at doses of 1, 2 or 3µg.kg-1 with bupivacaine 0.16% via caudal epidural route did not alter the consumption of morphine in the early postoperative period of children undergoing hypospadias repair.

Central pontine myelinolysis after liver transplantation: is sodium the only villain? Case report.

BACKGROUND AND OBJECTIVES: Critically ill patients frequently develop neurologic symptoms, which frequently become a clinical challenge. Described approximately 50 years ago, pontine neuronal demyelination is a pathologic change associated with neurologic and psychiatric problems after liver transplantation. The objective of this report was to present a case of central pontine myelinolysis diagnosed after liver transplantation and to discuss its pathophysiology. CASE REPORT: A 29 years old female patient underwent liver transplantation for fulminant hepatic failure. Postoperatively, she developed neurologic symptoms characteristic of the Locked In Syndrome and the MRI showed changes compatible with central pontine myelinolysis. The patient did not develop dramatic changes in sodium plasma levels, which is frequently incriminated as the causal agent, and improved considerably within a few weeks. CONCLUSIONS: The etiology of central pontine myelinolysis is multifactorial, and special attention should be given to the group of patients at greater risk, such as those with sudden changes in the plasma levels of sodium, liver transplantation, chronic alcoholics, and malnourished. It is important to recognize that osmotic demyelination can develop in patients with low, normal, or elevated plasma levels of sodium, indicating the contribution of other trigger factors.

Mielinólise pontina central após transplante hepático: o sódio é o único vilão?: Relato de caso / Central pontine myelinolysis after liver transplantation: is sodium the only villain?: Case report / Mielinólisis pontina central después del transplante hepático: ¿es el sodio el único villano?: Relato de caso

JUSTIFICATIVA E OBJETIVOS: A ocorrência de sintomas neurológicos em pacientes gravemente enfermos é comum e, muitas vezes, um desafio propedêutico. Descrita há cerca de 50 anos, a desmielinização dos neurônios da região pontina é uma alteração patológica associada a quadros neurológicos e psiquiátricos após transplante hepático. O objetivo deste relato foi apresentar a mielinólise pontina central diagnosticada no pós-operatório de transplante hepático e discutir sua fisiopatologia. RELATO DO CASO: Paciente do sexo feminino, 29 anos, submetida a transplante hepático devido insuficiência hepática fulminante. No pós-operatório apresentou quadro neurológico característico de Síndrome Locked In e lesões compatíveis com mielinólise pontina central à ressonância nuclear magnética. A paciente não apresentou oscilações exageradas do sódio plasmático, íon frequentemente incriminado como agente causal, evoluindo com melhora significativa em algumas semanas. CONCLUSÕES: A mielinólise pontina central tem etiologia multifatorial e atenção especial deve ser dada ao grupo de pacientes com maior risco, tais como aqueles submetidos a alterações abruptas da natremia, transplantados de fígado, etilistas crônicos e desnutridos. É importante reconhecer que as síndromes desmielinizantes osmósticas podem surgir em pacientes com níveis séricos de sódio baixo, normal ou elevado, evidenciando a contribuição de outros fatores desencadeantes.

BACKGROUND AND OBJECTIVES: Critically ill patients frequently develop neurologic symptoms, which frequently become a clinical challenge. Described approximately 50 years ago, pontine neuronal demyelination is a pathologic change associated with neurologic and psychiatric problems after liver transplantation. The objective of this report was to present a case of central pontine myelinolysis diagnosed after liver transplantation and to discuss its pathophysiology. CASE REPORT: A 29 years old female patient underwent liver transplantation for fulminant hepatic failure. Postoperatively, she developed neurologic symptoms characteristic of the Locked In Syndrome and the MRI showed changes compatible with central pontine myelinolysis. The patient did not develop dramatic changes in sodium plasma levels, which is frequently incriminated as the causal agent, and improved considerably within a few weeks. CONCLUSIONS: The etiology of central pontine myelinolysis is multifactorial, and special attention should be given to the group of patients at greater risk, such as those with sudden changes in the plasma levels of sodium, liver transplantation, chronic alcoholics, and malnourished. It is important to recognize that osmotic demyelination can develop in patients with low, normal, or elevated plasma levels of sodium, indicating the contribution of other trigger factors.

JUSTIFICATIVA Y OBJETIVOS: El aparecimiento de síntomas neurológicos en pacientes gravemente enfermos es común y muchas veces, es un reto propedéutico. Descrita hace cerca de 50 años, la desmielinización de las neuronas de la región pontina, es una alteración patológica asociada a cuadros neurológicos y psiquiátricos posteriores al transplante hepático. El objetivo de este relato, fue presentar la mielinólisis pontina central diagnosticada en el postoperatorio de transplante hepático y discutir su fisiopatología. RELATO DEL CASO: Paciente del sexo femenino, 29 años, sometida a transplante hepático debido a un fracaso hepático fulminante. En el postoperatorio, presentó un cuadro neurológico característico de Síndrome Locked In y lesiones compatibles con la mielinólisis pontina central a la resonancia nuclear magnética. La paciente no presentó oscilaciones exageradas del sodio plasmático, que es el ión frecuentemente acusado de ser el agente causador, y evolucionó con una mejoría significativa en algunas semanas. CONCLUSIONES: La mielinólisis pontina central tiene una etiología multifactorial, y una atención especial debe dársele al grupo de pacientes con mayor riesgo, tales como los sometidos a alteraciones abruptas de la natremia, transplantados de hígado, etilistas crónicos y desnutridos. Es importante reconocer, que los síndromes de desmielinización osmósticos pueden surgir en pacientes con niveles séricos de sodio bajo, normal o elevado, evidenciando la contribución de otros factores desencadenantes.