Different protocols of postconditioning does not attenuate mesenteric ischemia-reperfusion injury after short-term reperfusion / Diferentes protocolos de pós-condicionamento não atenua a lesão de isquemia e reperfusão mesentérica após curto período de reperfusão

ABSTRACT Background: Mesenteric ischemia is a challenging diagnosis. Delay in diagnosis can lead to extent bowel necrosis and poor outcomes. Ischemia and reperfusion syndrome plays an important role in this scenario. Aim: To access effects of different post-conditioning cycles on mesenteric ischemia-reperfusion syndrome. Method: Twenty-five rats were assigned into five groups: Sham, used to establish normal parameters; control group, submitted to mesenteric ischemia for 30 min; in groups GP3, GP1 and GP30, ischemia was followed by post-conditioning protocol, which consisted of 1 cycle of 3 min (GP3), 3 cycles of 1 min (GP1) or 6 cycles of 30 s (GP30), respectively. Ileum samples were harvested after one hour of reperfusion. Intestinal mucosal injury was evaluated through histopathological analysis. Results: The average of mesenteric injury degree was 0 in the sham group, 3.6 in the control group, 3.4 in GP3, 3.2 in GP1, and 3.0 in GP30; villous length average was 161.59 in sham group, 136.27 in control group, 135.89 in GP3, 129.46 in GP1, and 135.18 in GP30. Was found significant difference between sham and other groups (p<0.05); however, there was no difference among post-conditioning groups. Conclusion: Post-conditioning adopted protocols were not able to protect intestinal mucosa integrity after mesenteric ischemia and short term reperfusion.

RESUMO Racional: O desfecho satisfatório na abordagem cirúrgica da obesidade deve contemplar, além da perda de peso, alteração significativa nas comorbidades preexistentes e na qualidade de vida dos pacientes. Objetivo: Avaliar a qualidade de vida no pós-operatório tardio de pacientes submetidos à cirurgia de gastrectomia vertical por videolaparoscopia. Métodos: Foi aplicado o questionário "Bariatric Analysis and Reporting Outcome System" (BAROS) em pacientes submetidos à gastrectomia vertical por videolaparoscopia. Resultados: Foram avaliados 47 pacientes, entre 21 e 60 anos de idade. O IMC médio antes da operação era 43,06±5,87 kg/m². A média percentual de redução do excesso de peso após foi de 85,46±23,6%. A pontuação obtida pelos pacientes no questionário sobre a melhora na qualidade de vida evidenciou resultado excelente (36,17%), ótimo (40,43%), bom (21,28%) e razoável (2,13%). Houve melhora clínica após a operação em todas as comorbidades investigadas. Conclusão: A perda de peso foi fundamental para a melhoria na qualidade de vida e proporcionou resolução ou a melhora clínica em todas as comorbidades investigadas.

Exogenous normal lymph alleviates microcirculation disturbances and abnormal hemorheological properties in rats with disseminated intravascular coagulation

Disturbances of the microcirculation and abnormal hemorheological properties are important factors that play an important role in disseminated intravascular coagulation (DIC) and result in organ dysfunction or failure. In the present study, we established an animal model of DIC using intravenous Dextran 500 in rats, and used exogenous normal lymph corresponding to 1/15 of whole blood volume for injection through the left jugular vein. We found that normal lymph could improve the blood pressure and survival time of rats with DIC. The results regarding the mesenteric microcirculation showed that the abnormality of the diameter of mesenteric microvessels and micro-blood flow speed in the DIC+lymph group was significantly less than in the DIC+saline group. Whole blood viscosity, relative viscosity, plasma viscosity, hematocrit (Hct), erythrocyte sedimentation rate (ESR), and electrophoresis time of erythrocytes were significantly increased in the DIC+saline group compared to the control group. The electrophoretic length and migration of erythrocytes from the DIC+saline and DIC+lymph groups were significantly slower than the control group. Blood relative viscosity, Hct, ESR, and electrophoretic time of erythrocytes were significantly increased in the DIC+lymph group compared to the control group. Whole blood viscosity, relative viscosity and reduced viscosity were significantly lower in the DIC+lymph group than in the DIC+saline group, and erythrocyte deformability index was also significantly higher than in the DIC+saline and control groups. These results suggest that exogenous normal lymph could markedly improve the acute microcirculation disturbance and the abnormal hemorheological properties in rats with DIC induced by Dextran 500.

Modelo experimental de isquemia: reperfusão intestinal por clampeamento de aorta abdominal em ratos Wistar / Experimental model of mesenteric ischemia: reperfusion by abdominal aorta clamping in Wistar rats

OBJETIVO: desenvolver um modelo experimental de isquemia global normotérmica transitória capaz de demonstrar os tempos de isquemia e reperfusão necessários para desenvolvimento de lesão de isquemia/reperfusão em intestinos delgados de ratos Wistar através clampeamento de aorta abdominal suprarrenal. MÉTODOS: Vinte ratos Wistar adultos machos, pesando entre 250 e 350g, foram distribuídos aleatoriamente em cinco grupos, com quatro ratos cada, e submetidos a tempos crescentes de isquemia (0 - 30 - 45 - 60 - 90 minutos). Dentro de cada grupo, à exceção do grupo controle, dois ratos foram submetidos à 60 minutos de reperfusão e dois à 90 minutos. Após os procedimentos, procedeu-se análise histológica através de medição de áreas de necrose. RESULTADOS: O grau de necrose intestinal variou de 15 a 54% (p=0,0004). Houve tendência de aumento progressivo no grau de lesão relacionado ao aumento no tempo de isquemia, contudo, os maiores graus de lesão foram observados nos menores tempos de reperfusão. A análise do coeficiente de variação de necrose entre os dez grupos de isquemia/reperfusão demonstrou diferença estatisticamente significante em 15 postos, sendo 13 relacionados ao grupo controle. CONCLUSÃO: O modelo foi capaz de demonstrar os tempos necessários para que ocorra lesão de isquemia/reperfusão intestinal através de clampeamento aórtico e poderá servir como base para facilitar o desenvolvimento de estudos voltados para a compreensão deste tipo de lesão.

OBJECTIVE: To develop an experimental model of global normothermic ischemia able to demonstrate the transient ischemia and reperfusion periods required for development of ischemia/reperfusion injury in the small intestines of Wistar rats by clamping the abdominal aorta. METHODS: Twenty adult male Wistar rats weighing 250-350g were randomly divided into five groups with four rats each and submitted to increasing times of ischemia (0 - 30 - 45 - 60 - 90 minutes). Within each group, except the control one, two rats underwent 60 minutes of reperfusion and two 90 minutes. After the procedures, histological analysis was conducted by measurement of areas of necrosis. RESULTS: The degree of intestinal necrosis ranged from 15% to 54% (p = 0.0004). There was progressive increase in the degree of injury related to increase in ischemic time. However, greater degrees of injury were observed in the lowest times of reperfusion. The analysis of the coefficient of variation of necrosis among the ten groups of ischemia/reperfusion showed a statistically significant difference in 15 areas, 13 related to the control group. CONCLUSION: The model was able to show the periods required for the occurrence of ischemia/reperfusion injury by aortic clamping and can serve as a basis to facilitate the development of studies that aim at understanding this kind of injury.

CT Angiographic Demonstration of a Mesenteric Vessel "Whirlpool" in Intestinal Malrotation and Midgut Volvulus: a Case Report

Although the color Doppler ultrasonography diagnosis of intestinal malrotation with midgut volvulus, based on the typical "whirlpool" appearance of the mesenteric vascular structures is well-defined in the peer-reviewed literature, the combination of both the angiographic illustration of these findings and the contemporary state-of-the-art imaging techniques is lacking. We report the digital subtraction angiography and multidetector computed tomography angiography findings of a 37-year-old male with intestinal malrotation.

In vivo observation of mesenteric leukocyte-endothelial interactions after cecal ligation/puncture and surgical sepsis source control

PURPOSE: Cecal ligation and puncture (CLP) has been used as a useful model for the induction of polymicrobial sepsis. Necrotic tissue resection and peritoneal lavage (REL) are the surgical procedures for controlling perforated appendicitis. The aim of this study was to evaluate leukocyte-endothelial interactions in the rat mesentery in vivo after CLP and REL. METHODS: Thirty-seven male Wistar rats (250-300 g) underwent laparotomy and were randomly assigned to the following groups: 1) SHAM; 2) CLP: animals submitted to CLP, 3) CLP+REL: animals submitted to CLP and REL. Mesenteric leukocyte-endothelial interactions were studied by intravital microscopy assessed once in each animal (3-5 postcapillary venules, 15-25 æm diameter) 24 hours after intervention. Follow-up was performed in all animals; this included analysis of glycemia, lactate, hematocrit, white blood cell count as well as a functional score that was the sum of scoring on the following parameters: alertness, mobility, piloerection, diarrhea, encrusted eyes, and dirty nose and tail. RESULTS: None of the animals showed significant changes in body weight (265 ± 20 g) or in hematocrit levels (46 percent ± 2 percent) during the experimental protocol. Compared to SHAM animals, CLP animals showed an increased number of rolling (2x), adherent, and migrating leukocytes (7x) in the mesenteric microcirculation, an increase in blood glucose (136 ± 8 mg/dL), lactate (3.58 ± 0.94 mmol/L), white cell count (23,570 ± 4,991 cells/mm³) and functional alterations (score 11 ± 1), characterized by impaired alertness and mobility, and presence of piloerection, diarrhea, encrusted eyes, and dirty nose and tail. The REL procedure normalized the number of rolling, adherent, and migrated leukocytes in the mesentery; glycemia; lactate; and white blood cell count. The REL procedure also improved the functional score (7 ± 1). CONCLUSION: Local and systemic inflammation was induced by CLP, while REL completely...

OBJETIVO: O procedimento de ligadura cecal e perfuração (CLP) tem sido usado como um modelo útil de indução de sepse polimicrobiana. A ressecção do tecido necrosado e lavagem peritoneal (REL) são procedimentos cirúrgicos freqüentemente utilizados para controlar uma apendicite perfurada. O objetivo desse estudo foi avaliar in vivo as interações leucócito-endotélio no mesentério de ratos após a CLP e REL. MÉTODOS: Trinta e sete ratos Wistar machos (250-300 g) foram submetidos à laparotomia e aleatoriamente divididos em grupos: 1) SHAM, 2) CLP: ratos submetidos à CLP, 3) CLP+REL: animais submetidos à CLP e REL. As interações leucócito-endotélio no mesentério foram estudadas através de microscopia intravital somente uma vez em cada animal (3-5 vênulas pós-capilares, 15-25 æm diâmetro), 24-horas após as intervenções. A evolução clínica foi realizada em todos os animais, incluindo glicemia, lactato, hematócrito, número total de células brancas e um escore funcional, o qual foi considerado como a somatória dos seguintes parâmetros: estado de alerta, mobilidade, piloereção, diarréia, olhos encrustados, e nariz e cauda sujos. RESULTADOS: Os animais não apresentaram alterações significantes no peso (265 ± 20 g) e hematócrito (46 ± 2 por cento) ao longo do estudo. Comparados ao SHAM, os animais CLP apresentaram aumento no número de leucócitos em rolamento (2x), aderidos (7x) e migrados (7x) na microcirculação mesentérica, aumentos da glicemia (136 ± 8 mg/dL), lactato (3,58 ± 0,94 mmol/L), leucocitose (23.570 ± 4.991 células/mm³) e alterações clínicas (escore 11±1), caracterizadas por comprometimento do estado de alerta e mobilidade, e presença de piloereção, diarréia, olhos encrustados, nariz e cauda sujos. REL normalizou o número de leucócitos em rolamento, aderidos e migrados no mesentério, a glicemia, o lactato e o número de leucócitos circulantes. REL também melhorou o escore clínico (7 ± 1). CONCLUSÃO: A CLP induziu inflamação local e sistêmica. A...

Endovascular stent implantation in the coeliac and superior mesenteric arteries in the treatment of chronic mesenteric ischemia.

Mesenteric ischemia is a rare but serious cause of abdominal pain.We present the case of a man who had symptomatic mesenteric ischemia, secondary to a superior mesenteric artery stenosis in conjunction with a coeliac artery stenosis. He was treated with balloon angioplasty and stent insertion, and showed good symptomatic improvement.

Isquemia intestinal / Mesenteric ischemia

La isquemia mesentérica es una insuficiencia circulatoria inadecuada para los requerimientos de la pared intestinal. Su presentación suele ser de extrema gravedad con historia de dolor abdominal crónico y/o infarto intestinal, con alta mortalidad y diagnóstico tardío. En el presente trabajo se realiza una revisión con los avances en el diagnóstico y manejo de esta condición, de acuerdo al compromiso vascular y los territorios afectados, con énfasis en su reconocimiento precoz y tratamiento agresivo, principalmente quirúrgico en los casos proximales al colon y médico en este último.

Pathophysiology of mesenteric ischemia/reperfusion: a review

Durante a isquemia, as estruturas celulares são progressivamente lesadas, mas a restauracão do fluxo sanguíneo, paradoxalmente, pode agravar o dano celular isquêmico. O mecanismo das lesões de isquemia e reperfusão (I/R) ainda não foram completamente definidos e muitos estudos têm sido realizados na tentativa de encontrar uma terapia ideal para I/R mesentérica. A oclusão e a reperfusão das artérias esplâncnicas provocam alteracões locais e sistêmicas derivadas principalmente da liberacão de substâncias citotóxicas e da interacão entre neutrófilos e células endoteliais. As substâncias envolvidas no processo, como radicais livres derivados do oxigênio, óxido nítrico, fatores de transcricão, sistema complemento, serotonina e proteases pancreáticas, são discutidas na presente revisão. Os mecanismos de apoptose, repercussão sistêmica, terapêutica e métodos de avaliacão também são discutidos.

Gas in the portal system in a patient with an irreversible bowel ischaemia: a case report

The presence of gas in the portal system is an ominous radiological sign. We report a 63-year-old male patient presented on 27th of March 2003 with acute peritonitis secondary to acute irreversible intestinal ischemia caused by acute thrombosis of the superior mesenteric artery. Abdominal computerized tomography scans showed hepatic portal venous gas. The etiology, imaging features and clinical significance of hepatic portal venous gas are discussed. The computerized tomography scan signs of strangulation include thickening of the bowel wall, pneumatosis intestinalis, and portal venous gas

Mesenteric ischemia and portal hypertension caused by splenic arteriovenous fistula.

Splenic arteriovenous fistula is rare and usually presents with features of established portal hypertension (PHT). Presentation as acute mesenteric ischemia with features of acute PHT is uncommon. We report a 35-year-old lady who presented with severe abdominal pain, diarrhea and ascites, which was found to result from mesenteric ischemia and acute PHT secondary to splenic arteriovenous fistula. She underwent resection of fistula, which resulted in complete symptom relief.

Determination of macromolecular exchange and PO2 in the microcirculation: a simple system for in vivo fluorescence and phosphorescence videomicroscopy

We have developed a system with two epi-illumination sources, a DC-regulated lamp for transillumination and mechanical switches for rapid shift of illumination and detection of defined areas (250-750 æm²) by fluorescence and phosphorescence videomicroscopy. The system permits investigation of standard microvascular parameters, vascular permeability as well as intra- and extravascular PO2 by phosphorescence quenching of Pd-meso-tetra (4-carboxyphenyl) porphine (PORPH). A Pechan prism was used to position a defined region over the photomultiplier and TV camera. In order to validate the system for in vivo use, in vitro tests were performed with probes at concentrations that can be found in microvascular studies. Extensive in vitro evaluations were performed by filling glass capillaries with solutions of various concentrations of FITC-dextran (diluted in blood and in saline) mixed with different amounts of PORPH. Fluorescence intensity and phosphorescence decay were determined for each mixture. FITC-dextran solutions without PORPH and PORPH solutions without FITC-dextran were used as references. Phosphorescence decay curves were relatively unaffected by the presence of FITC-dextran at all concentrations tested (0.1 æg/ml to 5 mg/ml). Likewise, fluorescence determinations were performed in the presence of PORPH (0.05 to 0.5 mg/ml). The system was successfully used to study macromolecular extravasation and PO2 in the rat mesentery circulation under controlled conditions and during ischemia-reperfusion

Ecotomografía Doppler duplex mesentérico: revisión bibliográfica / Doppler duplex ultrasound in mesentery: review

A review of Doppler-duplex ultrasound in the evaluation of splachnic arteries is presented. Emphasis is made on the study in pre and postprandial examination. A detailed description of the scanning technique is made

Medical Quiz acute mesenteric ischaemia

A 62 years old Bahraini man was admitted through the surgical clinic with recurrent attacks os central abdominal pain of several month's duration. He gave a history of ischaemic heart disease but was not on regular treatment. Previous echocardiography had shown impaired systolic left ventricular function with global hypokinesia. On the second day of his admission he developed a cold left lower limb. Clinical examination revealed an absent pulse from dorsalis pedis and posterior tibial arteries that was confirmed by duplex ultrasound. Following a femoral angiography [Fig. 1] he underwent a successful femoral embolectomy. On the first postoperative day he complained of severe central abdominal pain and became hypotensive and tachycardiac

Isquemia mesentérica aguda. Análisis retospectivo de 48 pacientes / Acute mesenteric ischemia. Retrospective analysis of 48 patients

La isquemia mesentérica aguda es una emergencia vascular que pone en peligro la vida y cuya mortalidad se encuentra en un rango de 60 a 100 po ciento. Cualquiera que sea su etiología, la interrupción aguda de la perfusión del intestino delgado y colon proximal progresa desde alteraciones fisiológicas potencialmente reversibles en la integridad del tejido hasta el infarto transmural completo con necrosis hemorrágica. Cuarenta y ocho pacientes estudiados retrospectivamente con promedio de edad de 60 años (rango 16-94). Veintisiete mujeres y 21 hombres. Los antecedentes mas frecuentes fueron quirúrgicos, cardiopatías y tabaquismo. La forma de presentación en todos los casos fue urgencia con abdomen agudo. Los síntomas más frecuentes fueron: dolor abdominal, náusea y vómito acompañados de datos de irritación peritoneal, ausencia de peristalsis y distensión abdominal. Todos los pacientes presentaron leucocitosis. El diagnóstico se apoyó en radiografías simples de abdomen, ultrasonido y tomografía computadas. Todos los pacientes fueron sometidos a laparotomía exploradora realizando resección intestinal y anastomosis primaria en 28 pacientes, laparotomía exploradora sin resección en 11, laparotomía exploradora sin resección intestinal con procedimiento de second look en siete y laparotomía exploradora con resección y realización de estomas en dos pacientes. En 90 por ciento se encontró trombosis mesentérica y el resto isquemia msesentérica. Diez pacientes se reintervinieron por dehiscencia de anastomosis, oclusión intestinal, nuevo evento de isquemia intestinal y abdomen agudo. Las complicaciones postoperatorias más frecuentes fueron neumonía, choque hipovolémico y sepsis. Fallecieron 56 por ciento del total de pacientes

Insuficiência vascular mesentérica aguda / Acute mesenteric ischemia

Estudou-se de forma exploratória, 22 prontuários de portadores de insuficiência mesentérica, atendidos em 3 hospitais da Grande Florianópolis, num período de 8 anos. Desses, 9 eram do sexo feminino e 13 do masculino. A idade média de acometimento foi igual a 68, 31 anos para ambos os sexos. Dos 22 pacientes, 86,36 por cento evoluiram para óbito e 13,63 por cento obtiveram alta hospitalar. Ressaltam-se aqui os aspectos clínicos e laboratoriais encontrados e que muito contribuem para o diagnóstico precoce e consequentemente para o bom prognóstico, como também o tratamento instituído.

Extracellular and membranal bound calcium on the contraction of mesenteric arteries of the rat

Después de perfundir la arteria mesentérica anterior de la rata y sus ramas con una solución de Tyrode sin Ca, que agora el Ca extracelular, es posible provocar contracciones mediante la inyección "en bolo" de Noradrenalina (NA), Adrenalina (AD), Serotonina (ST) y Vasopresina (VP). La infusión continua de NA produce un efecto vasoconstrictor sostenido cuando el líquido intersticial contiene Ca, pero declina cuando ést falta. Todos a la solución perfusora privada de Ca. Estos no se recuperan, perfundiendo una solución sin Ca, pero rápidamente si ésta lo contiene. Tanto el La3+ como el EDTA no ingresan a la célular muscular, sino que desplazan al Ca fijado al plasmalema, que pone en marcha el mecanismo contráctil. Cuando éste falta, los agonistas carecen del Ca que lleva su mensaje al interior de la célula y son, por lo tanto, inefectivos. Este Ca mensajero membranal es reemplazado por el Ca iónico extracelular, pero no por el Ca intracelular. Esta interpretación permite explicar el "efecto dual" de la NA, que postula que los efectos breves o fásicos se deberían a la liberación de Ca intracelular, mientras que los sostenidos o tónicos al ingreso de Ca extracelular. Cuando el medio no contiene Ca, los agonistas son capaces de provocar vasoconstricción a partir de Ca fijado a la membrana celular. Como éste no es repuesto, si el medio carece de Ca, las respuestas vasoconstrictoras delcina y acaban agotándose