Elizabeth Milla Tambara

Estudo comparativo de eficácia e segurança entre propofol e midazolam durante sedação para colonoscopia

OBJETIVO: Comparar a seguranca e a eficacia do propofol com a do midazolam na sedacao profunda durante colonoscopias. METODOS: Sessenta e seis pacientes foram submetidos a colonoscopias e estudados prospectivamente. Um total de 50 pacientes recebeu 3,25 mg.kg-1 de peso de propofol. No grupo controle de 16 pacientes foi administrado 2,05 mg.kg-1 de peso de midazolam. A dose de manutencao foi titulada de acordo com a necessidade. Os parâmetros cardiovasculares e respiratorios observados foram a saturacao de oxigenio, pressao arterial sistolica e diastolica e frequencia cardiaca. Apos o procedimento foi realizado um questionario sobre intercorrencias como dor, desconforto e satisfacao apos a colonoscopia, utilizando uma escala visual de zero a dez. Foi aplicado o teste t de Student para a analise estatistica. RESULTADOS: A amostra foi similar com relacao as variaveis idade, peso, sexo e condicao fisica. Houve diferenca estatistica significativa para os parâmetros saturacao de oxigenio do sangue e pressao arterial sistolica entre os dois grupos. Nao houve diferenca estatistica significativa para os parâmetros pressao arterial diastolica e pulso. Apesar das diferencas nos parâmetros cardiovasculares e respiratorios, nao houve repercussoes hemodinâmicas significativas. Nao houve diferenca estatistica no parâmetro dor e satisfacao. Os pacientes que apresentaram agitacao (25%) no grupo midazolam, relataram mais desconforto (p=0,038). CONCLUSAO: As variacoes nos parâmetros cardiovasculares e respiratorios, mesmo com diferencas significativas entre os grupos, nao causaram repercussoes clinicas significativas nos dois grupos, caracterizando a seguranca na sedacao profunda. A sedacao com midazolam ou propofol nao esta associada a niveis de dor e satisfacao diferentes entre os dois grupos. O grupo midazolan referiu significativamente mais desconforto que o grupo propofol.

Imunossupressão com tacrolimus favorece a regeneração hepática induzida por hepatectomia ampla em ratos

OBJETIVO: Avaliar em dois momentos distintos da regeneracao hepatica a influencia do Tacrolimus sobre o fenomeno da regeneracao hepatica desencadeada pela resseccao de 70% do parenquima hepatico em ratos plenamente desenvolvidos. METODOS: Utilizaram-se 40 ratos Wistar com peso medio de 510,08 g ± 11.66 g distribuidos aleatoriamente em dois grupos de 20, cada grupo subdividido em dois subgrupos conforme o dia da morte apos a hepatectomia. De acordo com o grupo os animais receberam por gavagem solucao aquosa de Tacrolimus 0,1 mg/kg/dia ou solucao salina no mesmo volume. Apos tres dias de pre-terapia todos foram submetidos a hepatectomia de 70% pela resseccao dos lobos hepaticos mediano e lateral esquerdo que foram pesados para posterior calculo da regeneracao hepatica pela formula de Kwon. Vinte e quatro horas ou sete dias apos a hepatectomia, 10 animais de cada grupo foram mortos, os figados remanescentes (regenerados) foram pesados e amostrados para realizacao de indice mitotico por hematoxilina-eosina e estudo imunoistoquimico com os marcadores PCNA e Ki-67. RESULTADOS: Os animais que receberam tacrolimus mostraram indice maior de regeneracao hepatica, atingindo significância estatistica quando comparado ao subgrupo de animais mantidos com placebo quando analisados pelos parâmetros: formula de Kwon, indice mitotico e marcador PCNA. A tendencia para o marcador Ki-67 foi identica aos outros parâmetros mas nao alcancou significância estatistica. CONCLUSAO: A imunossupressao com tacrolimus possui efeito estimulatorio no processo de regeneracao hepatica desencadeado pela hepatectomia 70% em ratos Wistar adultos, plenamente desenvolvidos.

Use of remifentanil to reduce propofol injection pain and the required propofol dose in upper digestive tract endoscopy diagnostic tests

BACKGROUND AND OBJECTIVES The introduction of propofol (2,6-diisopropylphenol) as a sedative agent has transformed the area of sedation for endoscopic procedures. However, a major drawback of sedation with the use of propofol is its high incidence of injection pain. The most widely used technique in reducing propofol injection pain is through the association of other drugs. The aim of this study was to evaluate the effect of remifentanil-propofol combination on the incidence of propofol injection pain and its influence on the total dose of propofol required for sedation in upper digestive tract endoscopy (UDE) diagnostic tests. METHOD One hundred and five patients undergoing upper digestive tract endoscopy were evaluated and randomly divided into 3 groups of 35 patients each. The Control Group received propofol alone; Study-group 1 received remifentanil at a fixed dose of 0.2mg/kg combined with propofol; Study-group 2 received remifentanil at a fixed dose of 0.3mg/kg combined with propofol. The incidence of propofol injection pain and the total dose of propofol required for the test were evaluated. The sample was very similar regarding age, weight, height, sex, and physical status. Statistical analysis was performed according to the nature of the evaluated data. Students t-test was used to compare the mean of age, weight, height (cm), and dose (mg/kg) variables between groups. The χ(2) test was used to compare sex, physical status, and propofol injection pain between groups. The significance level was α<0.05. RESULTS There was significant statistical difference between the study groups and the control group regarding the parameters of propofol injection pain and total dose of propofol (mg/kg) used. However, there were no statistical differences between the two study groups for these parameters. CONCLUSION We conclude that the use of remifentanil at doses of 0.2mg/kg and 0.3mg/kg was effective for reducing both the propofol injection pain and the total dose of propofol used.

Prevenção de isquemia hepática normotérmica durante perfusão hepática in situ com três diferentes soluções de preservação: análise experimental através de termografia por radiação infravermelha em tempo real

OBJECTIVE: To establish the usefulness of infrared radiation thermography on monitoring in situ liver perfusion with different preservation solutions during liver harvesting. METHODS: Twenty-four adult male Wistar rats, weighing 385.31g were randomly divided into four groups of six animals each according to the solution used to perfuse the liver (Euro-Collins® solution - EC group; Custodiol® solution - CUST group; Celsior® solution - CEL group and Ringer-Lactate solution - RL group). Under inhalatory ether anesthesia, animals were submitted to upper transversal laparotomy, exposure of median and left-lateral hepatic lobes, heparin injection (500 UI/Kg) through infrahepatic vena cava, portal vein infusion through 18G catheter of cold (4°C) solution according to the group of study. Infrared images, with respective temperature avaliations from hepatic surface, were picked up in real time by Therma CAM SC500® infrared camera positioned at constant distance from three fixed points of the diaphragmatic surface of median and left lateral lobes at the following moments regarding liver perfusion: immediately after laparotomy; after portal vein cannulation and immediately before solution infusion; at each minute from the beginning of liver perfusion during five minutes. Mean temperatures of each moment were compared intra and intergroups with the difference between means test with normal distribution, with significance level of 5% (p=0.05). RESULTS: There was statistically significant difference of means temperatures between the moment of laparotomy and immediately after cannulation; between this later and after the first minute of perfusion; and between the first and fifth minutes of infusion in all groups of study in a similar way. CEL group showed additional difference between the first and second minutes means temperatures. Intergroup comparison showed Euro-Collins solution with significant less cooling power when compared to all others solutions. CONCLUSION: It was possible to follow the liver cooling process during preservation solutions perfusion using infrared radiation images. Preservation solutions had similar behaviors, with Celsior® solution showing additional cooling power until the second minute of perfusion. Euro-Collins solution had less cooling power than other solutions studied.

Imunossupressão com tacrolimus favorece a regeneração hepática induzida por hepatectomia extensa em ratos

RESUMO - Racional - A regeneracao hepatica representa o resultado de respostas fisiologicas que ocorrem apos perdas de parenquima, como consequencia de agressoes toxico-medicamentosas, infecciosas, traumaticas ou cirurgicas. Objetivo - Avaliar, em dois momentos distintos da regeneracao hepatica, a influencia do tacrolimus sobre o fenomeno da regeneracao hepatica desencadeada pela resseccao de 70% do parenquima hepatico em ratos plenamente desenvolvidos. Metodo - Utilizaram-se 40 ratos Wistar com peso medio de 510,08 g ± 11.66 g divididos aleatoriamente em dois grupos de 20 (Estudo e Controle), cada grupo subdividido em dois subgrupos conforme o dia da morte apos a hepatectomia (24 horas e 7 dias). De acordo com o grupo os animais receberam por gavagem, diariamente, iniciando tres dias antes da hepatectomia e prolongando-se por todo o periodo de observacao, solucao aquosa de tacrolimus 0,1 mg/kg/dia ou solucao salina no mesmo volume. Apos tres dias de pre-terapia todos foram submetidos a hepatectomia de 70% pela resseccao dos lobos hepaticos mediano e lateral esquerdo que foram pesados para posterior calculo da regeneracao hepatica pela formula de Kwon. Vinte e quatro horas ou sete dias apos a hepatectomia, 10 animais de cada grupo foram mortos, os figados remanescentes (regenerados) foram pesados e amostrados para realizacao de indice mitotico por hematoxilina-eosina e estudo imunoistoquimico com os marcadores PCNA e Ki-67. Resultados - Os animais que receberam tacrolimus mostraram indice maior de regeneracao hepatica, atingindo significância estatistica quando comparado ao subgrupo de animais mantidos com placebo quando analisados pelos parâmetros: formula de Kwon, indice mitotico e marcador PCNA. A tendencia para o marcador Ki-67 foi identica aos outros parâmetros, mas nao alcancou significância estatistica. Conclusoes - A imunossupressao com tacrolimus possui efeito estimulante no processo de regeneracao hepatica desencadeado pela hepatectomia 70% em ratos Wistar adultos, plenamente desenvolvidos.ABSTRACT - Background - Liver regeneration is the result of physiological responses that occur after loss of parenchyma, as a consequence of drug abuse-toxic, infection, trauma or surgical procedure. Aim - To analyze, during two different moments of liver regeneration, the effect of the immunosuppressant tacrolimus on the 70% hepatectomy model-induced liver regeneration in adult rats. Methods - Forty Wistar adult rats, weighing 510.08+11.66 g were randomly divided into two groups (Study or Control), each group divided into two subgroups according to the death day after 70% hepatectomy (24 hours or 7 days). According to the group of study, rats received 0.1mg/Kg/day of tacrolimus or the same volume of saline solution, by gavage, daily, starting three days before hepatectomy until the end of observation (animal death´s day). After three days of pre-therapy, all animals were submitted to 70% hepatectomy by resection of median and left lateral hepatic lobes which were weighed for posterior calculation of liver regeneration by Kwon´s formula. Twenty four hours or seven days after hepatectomy 10 rats of each group were killed; the remaining liver (regenerated) was entirely resected, weighed and sampled for mitotic index on hematoxylin-eosin staining and immunohistochemical assays with PCNA and Ki-67 markers. Data were statistically analyzed by Mann-Whitney or Student “t” tests, with significance level of 5% (P<0.05). Results - Rats receiving tacrolimus showed statistically significant higher levels of liver regeneration when compared to placebo according to Kwon’s formula, mitotic index and PCNA marker. Identical trend was found with Ki-67 marker, but without statistical significance. Conclusion - Tacrolimus-based immunossuppression has stimulatory effect on liver regeneration process induced by 70% hepatectomy in adult Wistar rats.

Avaliação ultrassonográfica de cicatriz uterina pós-cesariana segmentar transversa

PURPOSE To evaluate the thickness of the lower uterine segment by transvaginal ultrasound in a group of non-pregnant women and to describe the morphologic findings in the scar of those submitted to cesarean section. METHODS A retrospective study of 155 transvaginal ultrasound images obtained from premenopausal and non-pregnant women, conducted between January 2008 and November 2011. the subjects were divided into three groups: women who were never pregnant (Control Group I), women with previous vaginal deliveries (Control Group II) and women with previous cesarean section (Observation Group). We excluded women with a retroverted uterus, intrauterine device users, pregnant women and those with less than one year of tsince the last obstetrical event. The data were analyzed statistically with Statistica, version 8.0 software. ANOVA and LSD were used to compare the groups regarding quantitative variables and the Students t-test was used to compare the thickness of the anterior and posterior isthmus. The Spearman correlation coefficient was calculated to estimate the association between quantitative variables. P values <0.05 were considered statistically significant. RESULTS There was significant difference between the thickness of the anterior and posterior isthmus only in the group of women with previous cesarean section. Comparing the groups two by two, no significant differences between the thickness of the anterior and posterior isthmus were observed in the Control Groups, but this difference was significant when we compared the Observation Group with each Control Group. In the Observation Group, no correlation was found between the thickness of the isthmus and the number of previous cesarean deliveries or the time elapsed since the last birth. A niche was found in the cesarean scar in 30.6% of the women in the Observation Group, 93% of whom complained of post-menstrual bleeding. CONCLUSION The relationship between the thickness of the anterior and posterior wall of the lower uterine segment by transvaginal ultrasound is a suitable method for the evaluation of the uterine lower segment in women with previous cesarean sections.

Vasomotor effect after acute intoxication with bupivacaine and levobupivacaine in rats via intraperitoneal route analyzed via digital infrared imaging

BACKGROUND AND OBJECTIVES The study of the vasomotor effect of local anesthetics (LA) is of paramount importance for the analysis of the occurrence of cardiotoxic and neurotoxic effects, and drug interactions. In order to find a safer drug than racemic bupivacaine, this study aimed to analyze digital infrared imaging of acute vasomotor effect of bupivacaine and levobupivacaine in rats intraperitoneally. METHOD We used 30 male Wistar rats distributed into three groups (n=10) and subjected to an intraperitoneal injection of LA. In Group C (control) 1 mL 0.9% saline was injected intraperitoneally. In Group B (bupivacaine), intraperitoneal injection of 0.5% of racemic bupivacaine (S50-R50), dose of 20 mg.kg⁻¹ of body weight. In Group L (levobupivacaine), intraperitoneal injection of levobupivacaine 0.5% enantiomeric excess (S75-R25) in dose of 20 mg.kg⁻¹ of body weight. The procedure was thermographicly continuously filmed from the time of pre-injection until 30 minutes after injection. The results of the recordings were analyzed in graphical form, verifying the maximum temperature of each rat and the average temperature of the system that housed the animal. RESULTS The results of graphic analysis showed no difference between Group L and Group C, and the average temperature remained stable throughout the experiment in both groups. In Group B, there was a phenomenon of temperature increase after intraperitoneal injection of bupivacaine. CONCLUSIONS The results demonstrated that the vasomotor effect of the acute toxicity of levobupivacaine was similar to Group C with saline, through macroscopic studies by infrared digital filmmaking, and that there were vasomotor changes (vasoconstriction), with bupivacaine intoxication in relation to both Group C and Group L.

Infrared image monitoring of local anesthetic poisoning in rats

BACKGROUND AND OBJECTIVES To evaluate the thermographic predictive value of local anesthetic poisoning in rats that indicates the early recognition of thermal signs of intoxication and enable the immediate start of advanced life support. METHODS Wistar rats underwent intraperitoneal injection of saline and ropivacaine; they were allocated into pairs, and experiments performed at baseline and experimental times. For thermography, central and peripheral compartment were analyzed, checking the maximum and average differences of temperatures between groups. Thermographic and clinical observations were performed for each experiment, and the times in which the signs of intoxication occurred were recorded. In the thermal analysis, the thermograms corresponding to the times of interest were sought and relevant data sheets extracted for statistical analysis. RESULTS Basal and experimental: the display of the thermal images at times was possible. It was possible to calculate the heat transfer rate in all cases. At baseline it was possible to see the physiology of microcirculation, characterized by thermal distribution in the craniocaudal direction. It was possible to visualize the pathophysiological changes or thermal dysautonomias caused by intoxication before clinical signs occur, characterized by areas of hyper-radiation, translating autonomic nervous system pathophysiological disorders. In animals poisoned by ropivacaine, there was no statistically significant difference in heat transfer rate at the experimental time. CONCLUSIONS The maximum temperature, medium temperature, and heat transfer rate were different from the statistical point of view between groups at the experimental time, thus confirming the systemic thermographic predictive value.

Efeito vasomotor após intoxicação aguda com bupivacaína e levobupivacaína via intraperitoneal em ratos, analisado por imagem infravermelha digital

JUSTIFICATIVA Y OBJETIVOS: El estudio del efecto vasomotor de los anestesicos locales (AL), es de suma importancia para el analisis del aparecimiento de efectos cardiotoxicos, neurotoxicos e interacciones medicamentosas. Con el fin de encontrar un farmaco mas seguro que la bupivacaina racemica, el presente estudio se propuso analizar por imagen infrarroja digital, el efecto vasomotor de la intoxicacion aguda de la bupivacaina y de la levobupivacaina via intraperitoneal en ratones. METODO: Fueron usados 30 ratones machos de la raza Wistar, divididos en tres grupos (n = 10) y sometidos a una inyeccion intraperitoneal de AL. En el Grupo C (Control), fue realizada una inyeccion intraperitoneal de suero fisiologico al 0,9% 1 mL. En el Grupo B (bupivacaina), una inyeccion intraperitoneal de bupivacaina racemica al 0,5% (R50-S50), dosis de 20 mg.kg-1 de peso. En el Grupo L (levobupivacaina), una inyeccion intraperitoneal de levobupivacaina al 0,5%, con exceso enantiomerico (S75-R25) en dosis de 20 mg.kg-1 de peso. Despues de procedio a la filmacion termografica continua desde el momento anterior a la inyeccion hasta 30 minutos despues de ella. Los resultados de las filmaciones se analizaron de forma grafica, verificando la temperatura maxima de cada raton y la temperatura promedio del sistema que abrigaba al animal. RESULTADOS: Los resultados del analisis grafico revelaron que no hubo diferencia entre el Grupo L y el Grupo C, y que la temperatu-ra promedio se mantuvo estable durante todo el experimento en los dos grupos. En el Grupo B, se produjo un fenomeno de aumento de temperatura despues de la inyeccion intraperitoneal de bupivacaina. CONCLUSIONES: Los resultados demostraron que el efecto vasomotor de la toxicidad aguda de la levobupivacaina fue similar al Grupo C con suero fisiologico, por medio de estudios macroscopicos por filmacion digital infrarroja, y que se produjeron alteraciones vasomotoras (vasoconstriccion), con la intoxicacion por bupivacaina respecto del Grupo C y con relacion al Grupo L.

Validation of a scale for the assessment of paravertebral muscle contraction during lumbar puncture

JUSTIFICATIVA Y OBJETIVOS: El objetivo es validar escala para la cuantificacion de la intensidad de la contraccion muscular paravertebral durante punciones lumbares, que auxiliara en la evaluacion de los efectos de la infiltracion con anestesico local en futuros trabajos. METODO: Participaron del estudio 31 observadores, de 2 Centros de Ensenanza y Entrenamiento (CEE-SBA), 12 del CEE-SBA 1 y 19 del CEE-SBA 2. Ocho participantes eran Medicos en Especializacion (ME) de primer ano, 6 de segundo ano y 17 eran Instructores. A los evaluadores fueron mostradas 23 peliculas, repetidas en 3 muestras, segun la secuencia aleatoria generada electronicamente. Las peliculas contenian estimulo de la piel con agujas de Quincke 25, 27 y 29G durante punciones lumbares y simulaciones de punciones (toque de puntas de jeringas). Los pacientes autorizaron la filmacion y utilizacion. Los movimientos de la musculatura paravertebral fueron cuantificados por los evaluadores, en la siguiente escala: 0 - ausencia de contraccion visible; 1 - contraccion leve, sin desplazamiento evidente de la columna; 2 - contraccion, con movimentacion moderada de la columna vertebral; 3 - contraccion de la musculatura con movimentacion que impide la progresion de la aguja. Para calculo de los contajes de cada pelicula, se consideraron las modas de las tres muestras. Se testo la consistencia interna por el coeficiente alfa de Cronbach y la concordancia entre los multiples observadores por el coeficiente alfa de Krippendorff. RESULTADOS: El coeficiente alfa de Cronbach fue 0,98. La mediana (cuartil inferior; superior) de los coeficientes alfa de Krippendorff fue 0,81 (0,78; 0,84). CONCLUSIONES: La escala presento un buen desempeno en lo que se refiere a la concordancia entre multiples observadores, pudiendo ser utilizada para cuantificar la contraccion de la musculatura paravertebral durante las punciones lumbares.BACKGROUND AND OBJECTIVES This study aimed at validating a scale to quantify the intensity of paravertebral muscle contraction during lumbar punctures, to be used in further studies on the effects of local anesthetic infiltration. METHODS This study involved 31 physicians, from two different Anesthesiology training centers located in two Brazilian cities, 12 of which were from institution 1 and 19 from institution 2. Eight participants were first-year residents, 6 were second-year residents and 17 were instructors. Participants were invited to watch 23 movies, repeated in 3 randomized electronically generated samples. Movies presented skin stimulation with 25, 27 and 29 G Quincke needles during lumbar puncture and puncture simulations (syringe tip touch). Patients authorized shooting and showing the movies. Physicians evaluated paravertebral muscles contraction according to the following scale: 0 - no sign of muscle contraction; 1 - mild muscular contraction without lumbar spine movement; 2 - muscles contraction with moderate lumbar spine movement; 3 - muscle contraction with movement precluding needle progression. Modes of the three samples were considered for each movie score calculation. Reliability analysis consisted of calculation of Cronbachs alpha, and intercoder reliability was evaluated by Krippendorffs alpha coefficient. RESULTS Cronbachs alpha was 0.98. Median (25th - 75th percentiles) of Krippendorffs alpha coefficients was 0.81 (0.78 - 0.84). CONCLUSIONS High internal and intercoder reliability found in this study suggests that the scale may be used in future studies to quantify paravertebral muscle contraction during lumbar puncture.