Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Includes bibliographical references (p. 126-136).

Thesis (MMed.(Anaesthesiology-Faculty of Health Sciences))--University of Pretoria, 2005. / Includes bibliographical references.

Orientador: Newton Nunes / Banca: José Antonio Marques / Banca: Danielli Parrilha de Paula / Resumo: A anestesia epidural é uma técnica disseminada, tanto pela facilidade de execução quanto pela segurança e conforto pós-operatório para o paciente. Entretanto, a administração de fármacos em vértebras craniais à sétima vértebra lombar com o uso de cateter epidural é pouco estudada. A presente pesquisa utilizou 16 cadelas, distribuídas aleatoriamente em 2 grupos, os quais se diferenciaram pela dose epidural de bupivacaína, 1mg/kg (G1) e 2 mg/kg (G2). A medicação pré anestésica foi feita com butorfanol e após a indução com etomidato, o cateter epidural foi posicionado à altura da primeira vértebra lombar. Após 30 minutos, foi administrada a bupivacaína e o bloqueio sensitivo foi avaliado durante 30 minutos. Em seguida, foi realizada a cirurgia de ovariohisterectomia eletiva, durante a qual, a eficácia do bloqueio anestésico foi avaliada. Também foram avaliados parâmetros cardiovasculares, ventilométricos e hemogasométricos. Os resultados das variáveis paramétricas foram analisados pelo software SAS 9.4 (2010) e não houve diferenças relevantes entre os grupos em relação aos parâmetros fisiológicos estudados. OS resultados referentes ao bloqueio sensitivo demonstram que o G2 apresentou bloqueio superior para todas as variáveis. Do mesmo modo, o G2 apresentou melhor bloqueio anestésico durante o transcirúrgico. Conclui-se que as duas doses de bupivacaína administradas à altura da primeira vértebra lombar não interferem significativamente nos parâmetros cardiovasculares, ventilométricos e hemogasométricos. Além disso, a dose de 2mg/kg determina melhor bloqueio sensitivo e anestésico que a dose de 1mg/kg nestas condições experimentais. A dose de 2 mg/kg permitiu a ovariohisterectomia em cadelas / Abstract: The epidural anesthesia is a widespread technique, presenting easy execution, safety and postoperative comfort for the patient. However, administration of drugs cranial to the seventh lumbar vertebrae using an epidural catheter is little studied. This study used 16 bitches that were separated randomly into 2 groups, which differed by epidural bupivacaine dose, 1 mgkg-1 (G1) or 2 mgkg-1 (G2). They were premedicated with butorphanol and and after the induction with etomidate, the epidural catheter was positioned at the first lumbar vertebra. After 30 minutes, bupivacaine was administered and sensory block was evaluated for 30 minutes. The anesthetic block was evaluated during an ovariohisterectomy elective surgery. The cardiovascular, ventilometric and blood gas parameters were also evaluated. The results of parametric variables were analyzed by SAS 9.4 software (2010). There were few differences between the groups in relation to physiological parameters but they remained near the normal range for the specie. The analysis of sensory block showed that G2 had better blocking for all variables. Similarly, the G2 showed better anesthetic block during the surgery. It concludes that the two bupivacaine doses administered up to the first lumbar vertebra, do not interfere significantly in the cardiovascular, ventilometric and blood gas parameters. Furthermore, the dose of 2mgkg-1 results in a better anesthetic and sensitive block than the dose of 1mgkg-1 in these experimental conditions. The dose of 2mgkg-1 was effective to ovariohysterectomy in bitches / Mestre

Orientador: Newton Nunes / Banca: Paula Ferreira da Costa / Banca: Roberto Thiesen / Banca: Luis Gustavo Gosuen Gonçalves Dias / Banca: Paulo Aléscio Canola / Resumo: A anestesia intravenosa com propofol é amplamente utilizada em Medicina Veterinária, entretanto, apesar de ser um bom hipnótico e apresentar indução e recuperação rápidas, esse fármaco não possui efeito analgésico. A fim de proporcionar aos suínos, espécie largamente utilizada na experimentação animal, uma anestesia multimodal, foi proposto nesse estudo a avaliação da associação de propofol ao óxido nitroso (N2O), o qual produz analgesia. Além disso, buscou-se definir as concentrações mais adequadas de oxigênio e N2O a serem fornecidas durante a anestesia. Para tal, foram utilizados 48 leitões em fase de creche, pré-medicados com azaperone, induzidos à anestesia com propofol e mantidos em infusão contínua deste agente sob ventilação espontânea. Os animais foram distribuídos em 6 grupos, que receberam as concentrações de 10, 30 e 50% de N2O (GN10, GN30 e GN50) ou ar comprimido (GA10, GA30 e GA50), associadas às frações inspiradas de oxigênio (FiO2) de 0,9, 0,7 e 0,5, respectivamente. Foi estudada a hemogasometria arterial e venosa mista, além da dinâmica cardiovascular, dinâmica respiratória e parâmetros intracranianos. A coleta de dados teve início 40 minutos após a indução anestésica e repetidas a cada 15 minutos, durante 60 minutos. Para a análise estatística dos resultados foi feita a análise de variância de duas vias para comparação entre grupos e de uma via para comparação de momentos, ambas seguidas pelo teste de Bonferroni. A dinâmica cardiovascular não apresentou dife... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Intravenous anesthesia with propofol is common practice in Veterinary Medicine. However, despite being a good hypnotic and provides fast anesthetic induction and recovery, has no analgesic effect. In order to provide pigs with a multimodal anesthetic protocol, it was proposed to evaluate the association of propofol with nitrous oxide (N2O), due to its analgesic properties. Moreover, the aim of this study was to define the most appropriate concentrations of oxygen and N2O to be provided during anesthesia. To that purposes, a total of 48 pigs in nursery phase were used. They were premedicated with azaperone and anesthetized with propofol, which was also used during anesthesia maintenance. The animals were assigned into 6 groups, as follows concentrations of 10, 30 and 50% N2O (GN10, GN30 and GN50) or compressed air (GA10, GA30 and GA50) associated with fraction of inspired oxygen (FiO2) of 0.9, 0.7 and 0.5, respectively. It was studied the arterial and mixed venous blood gas analysis, as well as cardiovascular dynamics, respiratory dynamics and intracranial parameters. Data collection began 40 minutes after the induction and it was repeated every 15 minutes for 60 minutes. The statistical analysis of results was performed by two-way analysis of variance for comparison between groups and one-way for times comparison, both followed by the Bonferroni test. Cardiovascular dynamics showed no difference between groups for heart rate (HR), systolic arterial pressure (SAP), diastolic a... (Complete abstract click electronic access below) / Doutor

Orientador: Carlos Augusto Araújo Valadão / Coorientador: André Escobar / Banca: Suzane lilian Beier / Banca: Guilherme de Camargo Ferraz / Resumo: A recuperação é uma fase crítica na anestesia de equinos. Tentativas precoces de retornar à posição quadrupedal são normalmente fracassadas podendo ocasionar quedas, injúrias e até mesmo fraturas. Técnicas para melhorar a qualidade de recuperação incluem o uso de agonistas adrenérgicos do tipo α2, os quais objetivam, neste contexto, a sedação do paciente, aumentando o tempo de decúbito e possibilitando maior tempo de eliminação do anestésico inalatório residual. O doxapram é um fármaco caracterizado por provocar aumento na frequência respiratória e, potencialmente, pode aumentar o clearance dos anestésicos inalatórios. Neste contexto, objetivou-se verificar a influência da administração dos fármacos xilazina e doxapram no tempo e na qualidade da recuperação de equinos submetidos à anestesia geral inalatória com isofluorano. Seis cavalos foram anestesiados durante 90 minutos quatro vezes, com intervalo de duas semanas entre os procedimentos, recebendo aleatoriamente os seguintes tratamentos após a interrupção do anestésico inalatório: xilazina 0,2 mg/kg, ou xilazina e doxapram (0,2 e 0,1 mg/kg, respectivamente), ou xilazina e doxapram (0,2 e 0,2 mg/kg, respectivamente), ou solução NaCl 0,9%. Todas recuperações foram filmadas e avaliadas por dois observadores não cientes dos tratamentos, por meio da escala visual analógica e escala qualitativa descritiva. Os escores foram analisados quanto à concordância por BlandAltman e quanto à diferença pela RM ANOVA, seguido pelo teste de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Recovery is a critical stage on equine anesthesia. Early attempts to assume upright position are seldom successful and frequently result on falls, injuries and even fractures. Techniques to improve anesthetic recovery include the use of α2- adrenergic agonists at recovery in order to increase the recumbency time permitting clearance a broader residual inhalational anesthetic. Doxapram is characterized by increasing respiratory rate. Potentially it can increase inhaled anesthetics clearence. The purpose of the present study was to verify to influence of xylazine and doxapram administration on time and quality of recovery of horses submitted to isoflurane inhalational anesthesia. Six horses were anesthetized four times, with a wash out period of two weeks. Each animal received one of the following randomized treatments following discontinuation of isoflurane anesthesia: xylazine 0.2 mg/kg, or xylazine plus doxapram (0.2 and 0.1 mg/kg, respectively), xylazine plus doxapram (0.2 and 0.2 mg/kg, respectively), or NaCl 0.9% solution. Recovery was filmed and posterior evaluated by two blind observes by a visual analogue scale and a qualitative descriptive scale. The scores were analyzed for agreement by Bland-Altman and for the difference by RM ANOVA followed by Tukey test. The parameters measured were analyzed with RM ANOVA followed by Tukey test (p < 0.05). There was no difference regarding times recovery between groups. The animals who received just xylazine presented better scores on quality analysis, followed by doxapram 0.2 mg/kg group, control group, and 0.1 mg.kg of doxapram group. The use of doxapram to re-sedate horses isoflurane anesthetized does not improve quality neither diminish time of recovery. / Mestre

The aim of this thesis is to quantify the intubation success rates and complication rates associated with GlideScope® video laryngoscopy in pediatric difficult airway patients. Difficult intubation is a major source of anesthesia-related morbidity and mortality in both adults and children (1-3). A number of studies have demonstrated that video laryngoscopy has helped to address this problem in adults, producing high intubation success rates with minimal complications (4-6). However, the literature on the use of videoscopes in children with difficult airways is sparse. We therefore sought to examine success and complication rates with the GlideScope®, a common type of video laryngoscope. To do so, we examined patient data from the Pediatric Difficult Intubation Registry, a collection of information on difficult airway incidents at fourteen pediatric teaching hospitals in the United States. From these data we calculated overall, first-pass, and rescue success rates on a per-attempt and per-patient basis, comparing them to success rates that resulted from using direct laryngoscopy. We also examined success rates for smaller groups of patients divided by Cormack-Lehane airway grade, weight, and muscle relaxant use. Finally, we assessed complication rates for patients undergoing GlideScope® intubation attempts and direct laryngoscopy. The GlideScope® produced lower success rates in our sample than those documented in adult difficult airway patients. This was particularly the case among smaller children and those with poor glottis visualization. However, the GlideScope® was superior to direct laryngoscopy by all measures and in all patient subgroups. We also found lower rates of hypoxemia and overall complications among patients receiving intubation attempts with only the GlideScope® versus only direct laryngoscopy. We believe this result may be related to the greater number of intubation attempts among patients receiving direct laryngoscopy.

OBJECTIVES: Congenital heart disease or CHD is a condition that affects 8 out of every 1,000 newborns. Every year more than 35,000 newborns are diagnosed with a congenital heart disease in the United States. Neonates and children with congenital heart disease are at increased risk for thrombotic events, especially those with a single ventricle physiology. The objective of this study was to assess the incidence and to identify the predictors of thrombosis in neonates and children with surgical and non-surgical heart diseases. METHODS: We performed a retrospective analysis of the Health Care and Cost Use Project Kid’s Inpatient Database. Neonates and children with a congenital heart disease were identified using the international classification of disease, 9th revision, clinical modification (ICD-9 CM) diagnostic codes, and grouped into two sub-categories of surgical heart and non-surgical heart diseases. These groups were further divided into four types of lesions: septal defects, single ventricle physiology, right ventricle outflow tract obstruction, and left ventricle outflow tract obstruction. Demographic characteristics, the presence of co-morbidities, the incidence of any thrombotic events, mortality rate, and the presence of additional complications such as acute kidney injury, sepsis, neurologic complications, the need for extracorporeal membrane oxygenation or ventricular assist device were also collected using ICD-9 CM codes. After propensity-matched analysis, neonates and children with a surgical congenital heart disease were compared with those with a non-surgical heart disease. We used uni- and multivariable logistic regression analysis to identify the predictors associated with the incidence of thrombotic events in both sub-group. RESULTS: In children with surgical heart disease, the incidence of thrombosis was 3.90%, compared with 2.13% in children with non-surgical heart disease. Furthermore, those with single ventricle physiology (surgical 2.13%; non-surgical 3.41%) or right ventricle outflow tract obstruction (surgical 1.54%; non-surgical 1.66) had the highest incidence of thrombosis. In addition to demographic characteristics (e.g. age) and the type of congenital heart disease, we observed that extracorporeal membrane oxygenation (ECMO) or ventricular assist device(VAD), the presence acute kidney injury, sepsis, and coagulopathy were strong predictors for the development of thrombotic events. CONCLUSIONS: Children with both surgical and non-surgical heart disease have an increased risk for thrombotic events, but those with a single ventricle physiology or a right ventricle outflow tract obstruction had a further increased risk.

Made available in DSpace on 2015-07-22T20:49:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-05-26 / A redução da massa de anestésico local é utilizada para minimizar os efeitos da hipotensão arterial, relacionados com raquianestesia para cesariana, diminuindo a incidência de eventos adversos maternos e preservando o bem-estar fetal. Esta estratégia tem o risco de resultar em anestesia insuficiente. Por outro lado, a hipotensão associada às maiores massas de anestésico local no espaço subaracnóideo pode ser controlada com infusão contínua profilática de fenilefrina.! Objetivo: Avaliar os efeitos da infusão contínua e profilática de fenilefrina para controle pressórico sobre os eventos adversos maternos e conceptuais em cesarianas com diferentes doses de bupivacaína na raquianestesia. Métodos: Foi realizado um estudo clínico prospectivo, não-aleatório, com 60 gestantes a termo, admitidas para cesariana eletiva. Todas as pacientes receberam raquianestesia com bupivacaína hiperbárica, acrescida de 5 mcg de sufentanil e 100 mcg de morfina. Foram alocadas em dois grupos, G12 e G8, na dependência da dose de bupivacaína hiperbárica administrada, 12 ou 8 mg, respectivamente. Foi realizada hidratação com 10 ml/Kg de solução de Ringer Lactato, 10 a 15 minutos antes da realização do bloqueio. Logo após, iniciou-se infusão contínua de 100 mcg/min de fenilefrina, com o objetivo de manter a pressão arterial dentro de limites estritos. Foram avaliados níveis sensitivos de bloqueio anestésico, consumo de vasopressores, incidência de eventos adversos maternos e condições do recém-nascido. Resultados: Os dados maternos mostraram que os dois grupos foram semelhantes, quanto ao nível de bloqueio anestésico, consumo de fenilefrina por unidade de tempo e incidências de hipotensão e hipertensão arterial, bradicardia, náuseas, vômitos, dispnéia, dor e tremores. Os dados conceptuais evidenciaram que os grupos foram semelhantes quanto à gasometria de artéria e veia umbilicais e lactato arterial e venoso. Todos os RN apresentaram pH > 7,2 e apenas 1 obteve pontuação < 7 no Apgar do primeiro minuto. Conclusões: Quando a pressão arterial é mantida dentro de controle rígido, por meio da infusão profilática contínua de fenilefrina, a incidência de eventos adversos maternos e conceptuais não difere quando a raquianestesia é realizada com 12 mg ou 8 mg de bupivacaína hiperbárica. / Background: Reduced local anesthetic dose is used for minimizing hypotension changes related with spinal anesthesia for cesarean section, optimizing both maternal and fetal outcomes. This strategy can result in neuroaxial block failure. On the other hand, the higher doses associated with hypotension can be controlled with continuous prophylactic infusion of phenylephrine. The present study assessed the effects of continuous infusion of phenylephrine under strict blood pressure control and the maternal-fetal outcomes in patients under spinal anesthesia for elective cesarean section with two anesthetic solution. Methods: The number of 60 patients, scheduled for elective cesarean section, was allocated into 2 non-randomized groups (30 individuals each) for this prospective clinical study identified as Group 12 (G12), who were administered 12 mg hyperbaric bupivacaine and; Group 8 (G8), who were injected with 8 mg hyperbaric bupivacaine. In both groups, the anesthetic solution was added to sufentanyl 5 !g and morphine 100 !g. Pre-hydration with Ringer Lactate solution – 10 ml/Kg. Continuous phenylephrine infusion started at the end of the spinal block, with a infusion rate of 100 !g/min under strict blood pressure control. Comparatively, sensitive anesthetic block level, vasopressor consumption, adverse maternal and neonate outcomes were evaluated. Results: The incidence of maternal adverse effects such as nausea, vomiting, dispnea, pain, tremor, and bradicardy, necessity of atropine, hypotension and hypertension showed no significant difference between groups. In addition, other parameters were evaluated in neonates, pH, pCO2, BE and lactate of umbilical vases and the consumption of phenylephrine per time unit. All neonates showed pH higher than 7.20, as well as the Apgar score higher than 7 at 5`; only one neonate of G12 showed the Apgar score lower than 7 at 1`. Conclusion: Strict arterial blood pressure performed with prophylactic continuous infusion of phenylephrine, doesn’t change the maternal and fetal outcomes in patients scheduled for elective cesarean section under spinal anesthesia. / TEDE / BV UNIFESP: Teses e dissertações

Made available in DSpace on 2015-10-06T13:03:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-21. Added 1 bitstream(s) on 2015-10-06T13:18:22Z : No. of bitstreams: 1 000849618.pdf: 1481058 bytes, checksum: 223cf15b98a011bfbc3974f15475fffa (MD5) / A anestesia epidural é uma técnica disseminada, tanto pela facilidade de execução quanto pela segurança e conforto pós-operatório para o paciente. Entretanto, a administração de fármacos em vértebras craniais à sétima vértebra lombar com o uso de cateter epidural é pouco estudada. A presente pesquisa utilizou 16 cadelas, distribuídas aleatoriamente em 2 grupos, os quais se diferenciaram pela dose epidural de bupivacaína, 1mg/kg (G1) e 2 mg/kg (G2). A medicação pré anestésica foi feita com butorfanol e após a indução com etomidato, o cateter epidural foi posicionado à altura da primeira vértebra lombar. Após 30 minutos, foi administrada a bupivacaína e o bloqueio sensitivo foi avaliado durante 30 minutos. Em seguida, foi realizada a cirurgia de ovariohisterectomia eletiva, durante a qual, a eficácia do bloqueio anestésico foi avaliada. Também foram avaliados parâmetros cardiovasculares, ventilométricos e hemogasométricos. Os resultados das variáveis paramétricas foram analisados pelo software SAS 9.4 (2010) e não houve diferenças relevantes entre os grupos em relação aos parâmetros fisiológicos estudados. OS resultados referentes ao bloqueio sensitivo demonstram que o G2 apresentou bloqueio superior para todas as variáveis. Do mesmo modo, o G2 apresentou melhor bloqueio anestésico durante o transcirúrgico. Conclui-se que as duas doses de bupivacaína administradas à altura da primeira vértebra lombar não interferem significativamente nos parâmetros cardiovasculares, ventilométricos e hemogasométricos. Além disso, a dose de 2mg/kg determina melhor bloqueio sensitivo e anestésico que a dose de 1mg/kg nestas condições experimentais. A dose de 2 mg/kg permitiu a ovariohisterectomia em cadelas / The epidural anesthesia is a widespread technique, presenting easy execution, safety and postoperative comfort for the patient. However, administration of drugs cranial to the seventh lumbar vertebrae using an epidural catheter is little studied. This study used 16 bitches that were separated randomly into 2 groups, which differed by epidural bupivacaine dose, 1 mgkg-1 (G1) or 2 mgkg-1 (G2). They were premedicated with butorphanol and and after the induction with etomidate, the epidural catheter was positioned at the first lumbar vertebra. After 30 minutes, bupivacaine was administered and sensory block was evaluated for 30 minutes. The anesthetic block was evaluated during an ovariohisterectomy elective surgery. The cardiovascular, ventilometric and blood gas parameters were also evaluated. The results of parametric variables were analyzed by SAS 9.4 software (2010). There were few differences between the groups in relation to physiological parameters but they remained near the normal range for the specie. The analysis of sensory block showed that G2 had better blocking for all variables. Similarly, the G2 showed better anesthetic block during the surgery. It concludes that the two bupivacaine doses administered up to the first lumbar vertebra, do not interfere significantly in the cardiovascular, ventilometric and blood gas parameters. Furthermore, the dose of 2mgkg-1 results in a better anesthetic and sensitive block than the dose of 1mgkg-1 in these experimental conditions. The dose of 2mgkg-1 was effective to ovariohysterectomy in bitches

Made available in DSpace on 2014-06-11T19:31:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-12-20Bitstream added on 2014-06-13T19:20:09Z : No. of bitstreams: 1 escobar_a_dr_jabo.pdf: 612819 bytes, checksum: 65d9566de830f99434d948b600cd78f8 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Objetivou-se, com este estudo, determinar se o butorfanol modifica a concentração anestésica mínima do sevofluorano (CAnMSEV) em função do tempo e avaliar os efeitos cardiorrespiratórios e eletrolíticos causados por essa associação em galinhas d'angola. Dez galinhas d'angola foram anestesiadas com sevofluorano e mantidas sob ventilação mecânica para determinação da CAnMSEV individual pelo modelo bracketing. A porcentagem de redução da CAnMSEV após a administração intravenosa de 2 ou 4,0 mg/kg de butorfanol em função do tempo foi estimada por regressão logística pelo método up-and-down. Em etapa subsequente, foram avaliados os efeitos cardiorrespiratórios do sevofluorano (1,0 CAnM) e de uma dose equipotente do sevofluorano (0,8 CAnM) associado ao butorfanol (4,0 mg/kg). A CAnMSEV média foi de 2,86 ± 0,09V%. Após 15 minutos da administração de 2,0 mg/kg de butorfanol, a redução da CAnMSEV foi de 8,52 ± 3,11V%. Após 15 e 30 minutos da administração de 4,0 mg/kg de butorfanol, a redução da CAnMSEV foi de 20,78 ± 4,37V% e 11,07 ± 8,2V%, respectivamente. A administração intravenosa de 4,0 mg/kg de butorfanol induziu taquicardia supraventricular e fibrilação ventricular em 62,5% e 25% dos animais, respectivamente. Foi observada diminuição da frequência cardíaca, hipotensão e depressão respiratória severa 1 minuto após a administração de 4,0 mg/kg de butorfanol. O butorfanol diminui de forma dosedependente a CAnMSEV por um curto período, contudo, a dose que proporcionou a maior redução da CAnMSEV não foi considerada segura nas condições deste estudo / The aim of this study was to determine the sevoflurane minimum anesthetic concentration (MACSEV), to measure the dose and temporal sevoflurane MAC sparing effect of butorphanol, and to evaluate the cardiorrespiratory changes of this combination in guinea fowl. Ten guinea fowls were anesthetized with sevoflurane under mechanical ventilation for individual MACSEV determination using the bracketing design. The percent of MACSEV reduction after intravenous administration of 2 or 4,0 mg/kg of butorphanol was estimated by logistic regression using the up-and-down method. Afterward, the cardiorespiratory changes of sevoflurane (1.0 MAC) and of an equipotent dose of sevoflurane (0.8 MAC) combined with butorphanol (4.0 mg/kg) were studied. The mean MACSEV was 2.86 ± 0.09%. After 15 minutes of the 2-mg/kg butorphanol injections, the sevoflurane MAC reduction was 8.52 ± 3.11%. After 15 and 30 minutes of the 4-mg/kg butorphanol injections, the sevoflurane MAC reduction was 20.78 ± 4.37% and 11.07 ± 8.2%, respectively. Intravenous administration of 4.0 mg/kg of butorphanol caused supraventricular tachycardia and ventricular fibrillation in 62.5% and 25% of the animals, respectively. Decrease in heart rate, severe hypotension, and respiratory depression were observed after one minute of butorphanol administration. Butorphanol dose-dependently decreased MACSEV for a short period; however, the dose that caused MAC sparing effect was not considered safe in this experimental conditions