Este trabalho foi financiado em parte pelo Instituto Nacional de Saúde concessão R01-HL095498, bem como com os recursos eo uso de instalações do Sistema de Saúde VA Connecticut, West Haven, CT.

1. Os procedimentos de anestesia e pré-operatória <ol><li> A indução da anestesia geral Aprovação pelo Animal Care Institucional e Comitê de uso apropriado é obtido. C57/black camundongos machos, com idade de 10 semanas são anestesiados. Entregar 4% isoflurano com 0,8 L / min de oxigênio a uma caixa de acrílico através de um vaporizador isoflurano e coloque o mouse para dentro. Alternativamente, se preferido pelo cirurgião, a anestesia intraperitoneal pode ser usada. </li><li> Preservar a anestesia Após a confirmação da anestesia pela falta de reação a pitada dedo do pé, o mouse é colocado sobre a mesa de operação em decúbito dorsal com uma máscara de silicone. Isoflurano é reduzida para 2%, para manter o nível de anestesia adequada. </li><li> Depilação Ventral cabelo é removido do pescoço para baixo-ventre usando um removedor de cabelo. Removedor de cabelo é preferido porque o cabelo que fica usando uma máquina de barbear pode interferir com o ultra-som Doppler. </li></ol> 2. Ultrasoun pré-operatóriod <ol><li> Objectivos do ultrassom Exame de ultra-som Doppler é realizado antes da cirurgia AVF, de forma a registrar os resultados de nível básico que podem ser comparados com os resultados pós-operatórios para ver as mudanças anatômicas e fisiológicas. </li><li> Os pontos de observação A veia jugular, supra e infra-renal, veia cava inferior (IVC), e da aorta abdominal são examinados utilizando tanto pulso Doppler e em modo-B. </li><li> Medidas Usando o modo B, o diâmetro de cada vasculatura é medido. Além disso, a velocidade máxima (pico de velocidade sistólica em artérias) e as formas de onda são registados em cada um dos pontos de medição descritos acima. </li></ol> 3. Procedimentos Operativos <ol><li> Rato Preparação Prepare o local da incisão com um anti-séptico tópico e continuar a técnica asséptica apropriada durante a cirurgia, incluindo o uso de uma cortina cirúrgica, luvas e instrumentos esterilizados, etc </li><li> Laparotomia Incisão na linha média abdominal é feita from borda inferior do fígado para um pouco acima do púbis. </li><li> A exposição da aorta e veia cava inferior. Um afastador é inserido e todos os intestinos são puxados para fora da cavidade abdominal para o lado direito e mantida envolta em gaze embebida em soro fisiológico. Dissecar a membrana que liga o retroperitônio e inferior do cólon para visualização completa da aorta e veia cava inferior. Aplicar pressão sobre a bexiga, se é dilatado e fica no caminho. </li><li> A exposição do local de punção O local da punção será entre meia a três quartos da distância da veia renal esquerda para bifurcação aórtica. (Figura 1) Dissecar a margem esquerda da aorta, de modo que possa ser perfurado. Tenha em atenção que a aorta é posicionado a cerca de 45 graus para trás da VCI e deve ser dissecado posteriormente em adição à esquerda. (Figura 2) O ponto mais importante desta cirurgia não é dissecar entre a aorta ea veia cava inferior. Manter longe deles. </li><li> A exposição do local de fixação da aorta Dissecar a aorta infrarenal de tecidos circundantes. Tenha cuidado para não ferir o IVC nas veias renais esquerda e da esquerda com seus afluentes à direita. </li><li> Clampeamento da aorta Prenda a aorta proximal, aplicando clipes de microcirurgia. </li><li> A rotação da aorta Ao agarrar o tecido conjuntivo em torno da aorta, a aorta girar de modo que o punção pode ser feita a partir do lado dorsal ligeiramente da aorta (Figura 2). </li><li> Punção da aorta até IVC Mantendo a aorta numa posição rodada, por meio de punção na aorta aos VCI usando uma agulha 25 G. (Figura 2) Se for bem sucedido, a agulha pode ser visto através da fina parede da VCI. </li><li> Hemostasia Ao puxar os tecidos retroperitoneais, incluindo os músculos, enrole o local da punção da aorta. Não comprimir a aorta contra a CIV, como for o coágulo FAV (Figura 3). </li><li> De-pinçamento da aorta Depois da confirmaçãoda hemostasia primária, de-clamp da aorta. Sangramento adicional pode ocorrer, mas ele pode ser interrompido com mais compressão descrito acima. Ao de-aperto, o sangue arterial pode ser visto fluindo para o IVC, em vez do fluxo sanguíneo venoso escuro. </li><li> Encerramento do abdômen Retorne as entranhas em sua posição natural e fechar o abdômen. </li></ol> 4. Os procedimentos pós-operatórios <ol><li> Cuidados pós-operatórios Após o fechamento do abdômen, isoflurano está parado. Cuidados pós-operatórios, incluindo analgesia e tratamento de feridas é aplicada de acordo com as instruções recomendadas pelo Animal Care Institucional e Comitê de uso. Para analgesia usamos buprenorfina a 0,1 mg / kg intrasmuscularly cada 12 horas durante 24 horas após os procedimentos cirúrgicos. </li><li> Ultra-som pós-operatória No primeiro dia após a operação, de ultra-som Doppler é realizada para confirmar a FAV. Além disso, outras variáveis ​​são medidos para verificar as alterações do pré-operatóriavalores. </li></ol>

<ol>
	<li>Allon, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Current+management+of+vascular+access.">Current management of vascular access.</a> Clinical Journal of the American Society of Nephrology. 2 (4), 786-800 (2007).</li><li>Dixon, B. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Why+don't+fistulas+mature?.">Why don't fistulas mature?.</a> Kidney International. 70 (8), 1413-1422 (2006).</li><li>Roy-Chaudhury, P., Spergel, L. M., Besarab, A., Asif, A., Ravani, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biology+of+arteriovenous+fistula+failure.">Biology of arteriovenous fistula failure.</a> Journal of Nephrology. 20 (2), 150-163 (2007).</li><li>Kudo, F. A., Muto, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Venous+identity+is+lost+but+arterial+identity+is+not+gained+during+vein+graft+adaptation.">Venous identity is lost but arterial identity is not gained during vein graft adaptation.</a> Arteriosclerosis, Thrombosis, and Vascular Biology. 27 (7), 1562-1571 (2007).</li><li>Muto, A., Yi, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Eph-B4+prevents+venous+adaptive+remodeling+in+the+adult+arterial+environment.">Eph-B4 prevents venous adaptive remodeling in the adult arterial environment.</a> The Journal of Experimental Medicine. 208 (3), 561-575 (2011).</li><li>Croatt, A. J., Grande, J. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+a+model+of+an+arteriovenous+fistula+in+the+rat:+the+effect+of+L-NAME.">Characterization of a model of an arteriovenous fistula in the rat: the effect of L-NAME.</a> The American Journal of Pathology. 176 (5), 2530-2541 (2010).</li><li>Misra, S., Fu, A. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+rat+femoral+arteriovenous+fistula+model:+increased+expression+of+matrix+metalloproteinase-2+and+-9+at+the+venous+stenosis.">The rat femoral arteriovenous fistula model: increased expression of matrix metalloproteinase-2 and -9 at the venous stenosis.</a> Journal of Vascular and Interventional Radiology. 19 (4), 587-594 (2008).</li><li>Kojima, T., Miyachi, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+relationship+between+venous+hypertension+and+expression+of+vascular+endothelial+growth+factor:+hemodynamic+and+immunohistochemical+examinations+in+a+rat+venous+hypertension+model.">The relationship between venous hypertension and expression of vascular endothelial growth factor: hemodynamic and immunohistochemical examinations in a rat venous hypertension model.</a> Surgical Neurology. 68 (3), 277-284 (2007).</li><li>Caplice, N. M., Wang, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neoangiogenesis+and+the+presence+of+progenitor+cells+in+the+venous+limb+of+an+arteriovenous+fistula+in+the+rat.">Neoangiogenesis and the presence of progenitor cells in the venous limb of an arteriovenous fistula in the rat.</a> American Journal of Physiology Renal Physiology. 293 (2), F470-F475 (2007).</li><li>Nath, K. A., Kanakiriya, S. K., Grande, J. P., Croatt, A. J., Katusic, Z. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increased+venous+proinflammatory+gene+expression+and+intimal+hyperplasia+in+an+aorto-caval+fistula+model+in+the+rat.">Increased venous proinflammatory gene expression and intimal hyperplasia in an aorto-caval fistula model in the rat.</a> The American Journal of Pathology. 162 (6), 2079-2090 (2003).</li><li>Karram, T., Hoffman, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Induction+of+cardiac+hypertrophy+by+a+controlled+reproducible+sutureless+aortocaval+shunt+in+the+mouse.">Induction of cardiac hypertrophy by a controlled reproducible sutureless aortocaval shunt in the mouse.</a> Journal of Investigative Surgery. 18 (6), 325-334 (2005).</li><li>Perry, G. J., Mori, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+variation+in+angiotensin-converting+enzyme+does+not+prevent+development+of+cardiac+hypertrophy+or+upregulation+of+angiotensin+II+in+response+to+aortocaval+fistula.">Genetic variation in angiotensin-converting enzyme does not prevent development of cardiac hypertrophy or upregulation of angiotensin II in response to aortocaval fistula.</a> Circulation. 103 (7), 1012-1016 (2001).</li><li>Guzman, R. J., Krystkowiak, A., Zarins, C. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+and+sustained+medial+cell+activation+after+aortocaval+fistula+creation+in+mice.">Early and sustained medial cell activation after aortocaval fistula creation in mice.</a> The Journal of Surgical Research. 108 (1), 112-121 (2002).</li><li>Castier, Y., Lehoux, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+neointima+lesions+associated+with+arteriovenous+fistulas+in+a+mouse+model.">Characterization of neointima lesions associated with arteriovenous fistulas in a mouse model.</a> Kidney International. 70 (2), 315-320 (2006).</li></ol>

Há vários relatos que descrevem AVF em ratos, incluindo AVF femoral, 6, 7 carótida para jugular AVF 8 e aorto-cava AVF. 9, 10 O rato é várias vezes maior do que o mouse, permitindo que a cirurgia mais fácil em comparação com o rato o mouse. No entanto, a fim de tirar vantagem das estirpes e variantes genéticas do rato, o processo deverá ser alargado para incluir os modelos de ratinho. Vários relatórios publicados anteriormente introduziu o modelo AVF em ratos, mas esses relat...

A opção mais comum escolhido para a terapia de substituição renal em pacientes com doença renal terminal é a hemodiálise. Acesso para hemodiálise é realizada por fístula arteriovenosa (FAV), enxerto artério-venosa, ou a colocação do cateter temporário. Embora AVF são o modo preferido de acesso, AVF ainda estão longe de ser perfeito. Taxas de permeabilidade de um ano primário FAV são apenas 60-65%, com muitas falhas devido a hiperplasia neointimal. A biologia molecular ea fisiologia da formação AVF normal e formação inadequadas permanece mal caracterizado. Como tal, muito se ganha na melhoria dos resultados FAV com o ganho que o acompanha na compreensão da regulação da formação de fístula 1-3. A exposição de uma veia com o fluxo arterial é vulgarmente estudada no contexto de enxertos de veias, que são modelos directos de desvio cirúrgico. 4, 5 Embora os enxertos de veia e AVF similarmente expor uma veia para um ambiente arterial, há vários di críticorenças entre eles. Primeiro, a resistência do leito de escoamento distal é muito mais baixa no FAV, como a FAV drena para o átrio direito, enquanto que o enxerto de veia drenos para os doentes, muitas vezes pequenas artérias distais, o que resulta num aumento do fluxo sanguíneo e tensão de cisalhamento na FAV. Em segundo lugar, o sangue venoso do membro da FAV pode ser uma mistura de sangue venoso e arterial que conduz a uma menor oxigenação em comparação com o conteúdo puramente arteriais no enxerto de veia. Em terceiro lugar, a veia da FAV não é removida do seu leito, levando à conservação do seu vaso venorum inervação e nervosas, em comparação com a transposição completa do enxerto de veia para o leito arterial. Por último, o número de anastomoses é geralmente de dois em enxertos de veias Considerando uma FAV tipicamente tem apenas um. No presente estudo, nós apresentamos um modelo de rato com fístula aorto-cava que pode ser usado para o estudo da FAV.

<table border="1">
	<tbody>
		<tr>
			<td>Name of equipment</td>
			<td>Company</td>
			<td>Catalog number</td>
			<td>Comments (optional)</td>
		</tr>
		<tr>
			<td>Vevo 770 ultrasound machine</td>
			<td>Visualsonics</td>
			<td>20-60 Mhz scan head; RMV-704</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Vascular clamp</td>
			<td>Roboz Surgical Instrument Co.</td>
			<td>RS-5424</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Clamp applying forceps</td>
			<td>Roboz Surgical Instrument Co.</td>
			<td>RS-5410</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>25 Gauge Needle</td>
			<td>Becton Dickinson</td>
			<td>BD PrecisionGlide Needle 25 G x 7/8 #305124</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

technical aspects of the mouse aortocaval fistula

Aspectos técnicos da criação de uma fístula arteriovenosa no rato são discutidos. Sob anestesia geral, uma incisão abdominal é feita, e a aorta ea veia cava inferior (IVC) são expostos. A aorta infra-renal da aorta proximal e distal são dissecados para a colocação de grampo e punção com agulha, respectivamente. É dada especial atenção para evitar a dissecção entre a aorta ea veia cava inferior. Depois de prender a aorta, uma agulha 25 G é usada para perfurar ambas as paredes da aorta para a VCI. O tecido conjuntivo circundante é utilizado para compressão hemostática. Criação bem sucedida da FAV vai mostrar o fluxo de sangue arterial pulsátil no IVC. A confirmação adicional da FAV bem sucedido pode ser conseguido através de ultra-som Doppler de pós-operatório.

Depois do treino, a sobrevivência, no primeiro dia pós-operatório é normalmente superior a 95%, no dia pós-operatório 7, a sobrevivência foi de 91,3% As figuras 1 e 2 mostram o local de punção ideal em cortes coronais e transversal,. Colocação do punção local é fundamental para a obtenção de boa sobrevida sem hemorragia excessiva. Óbitos intra-operatórias e as mortes pós-operatórias precoces são normalmente devido à hemorragia. Isto tende a ocorrer com dissecção excessiva entre a...

Watch this Scientific Journal Video about Technical Aspects of the Mouse Aortocaval Fistula at JoVE.com

Technical Aspects of the Mouse Aortocaval Fistula

O objectivo é o de produzir uma fístula artério-venosa que é simples e reprodutível. Este método não utiliza suturas ou cola adesiva. Por conseguinte, as amostras podem ser usadas, com a menor quantidade de materiais estranhos para análise.

Aspectos técnicos da artocava Fístula Rato

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta ...

technical-aspects-of-the-mouse-aortocaval-fistula

Research

JoVE Journal

Medicine

16.3K visualizações.  Yale University. O objectivo é o de produzir uma fístula artério-venosa que é simples e reprodutível. Este método não utiliza suturas ou cola adesiva. Por conseguinte, as amostras podem ser usadas, com a menor quantidade de materiais estranhos para análise.

Vídeo: Technical Aspects of the Mouse Aortocaval Fistula

Microsurgical Venous Pouch Arterial-Bifurcation Aneurysms in the Rabbit Model: Technical Aspects

For ruptured human cerebral aneurysms endovascular embolization has become an equivalent alternative to aneurysm clipping.1 However, large clinical trials have shown disappointing long-term results with unacceptable high rates of aneurysm recanalization and delayed aneurysm rupture.2 To overcome these problems, animal experimental studies are crucial for the development of better endovascular devices.3-5
Several animal models in rats, rabbits, canines and swine are available.6-8 Comparisons of the different animal models showed the superiority of the rabbit model with regard to hemodynamics and comparability of the coagulation system and cost-effectiveness.9-11 
The venous pouch arterial bifurcation model in rabbits is formed by a venous pouch sutured into an artificially created true bifurcation of both common carotid arteries (CCA). The main advantage of this model are true bifurcational hemodynamics.12 The major drawbacks are the sofar high microsurgical technical demands and high morbidity and mortality rates of up to 50%.13 These limitations have resulted in less frequent use of this aneurysm model in the recent years. These shortcomings could be overcome with improved surgical procedures and modified peri- and postoperative analgetic management and anticoagulation.14-16 Our techniques reported in this paper demonstrate this optimized technique for microsurgical creation of arterial bifurcation aneurysms.

An optimized technique for the microsurgical creation of arterial bifurcation aneurysms mimicking bifurcation human cerebral aneurysms is described. A venous pouch is sutured into an artificially created true bifurcation of both common carotid arteries. Facilitated microsurgical techniques and aggressive postoperative anticoagulation and analgesia lead to minimized morbidity rates and high aneurysm patency rates.

Microcirúrgica venoso Bolsa Bifurcação Arterial-aneurismas no Modelo de Coelho: Aspectos Técnicos

For ruptured human cerebral aneurysms endovascular embolization has become an equivalent alternative to aneurysm clipping.1 However, large clinical trials ...

Medicina

The Rabbit Blood-shunt Model for the Study of Acute and Late Sequelae of Subarachnoid Hemorrhage: Technical Aspects

Early brain injury and delayed cerebral vasospasm both contribute to unfavorable outcomes after subarachnoid hemorrhage (SAH). Reproducible and controllable animal models that simulate both conditions are presently uncommon. Therefore, new models are needed in order to mimic human pathophysiological conditions resulting from SAH.
This report describes the technical nuances of a rabbit blood-shunt SAH model that enables control of intracerebral pressure (ICP). An extracorporeal shunt is placed between the arterial system and the subarachnoid space, which enables examiner-independent SAH in a closed cranium. Step-by-step procedural instructions and necessary equipment are described, as well as technical considerations to produce the model with minimal mortality and morbidity. Important details required for successful surgical creation of this robust, simple and consistent ICP-controlled SAH rabbit model are described.

The experimental intracranial pressure-controlled blood shunt subarachnoid hemorrhage (SAH) model in the rabbit combines the standard procedures &#8212; subclavian artery cannulation and transcutaneous cisterna magna puncture, which enables close mimicking of human pathophysiological conditions after SAH. We present step-by-step instructions and discuss key surgical points for successful experimental SAH creation.

O coelho Modelo Blood-shunt para o Estudo da aguda e tardia Sequelas de hemorragia subaracnóidea: Aspectos Técnicos

Early brain injury and delayed cerebral vasospasm both contribute to unfavorable outcomes after subarachnoid hemorrhage (SAH). Reproducible and ...

A Murine Model of Arterial Restenosis: Technical Aspects of Femoral Wire Injury

Cardiovascular disease caused by atherosclerosis is the leading cause of death in the developed world. Narrowing of the vessel lumen, due to atherosclerotic plaque development or the rupturing of established plaques, interrupts normal blood flow leading to various morbidities such as myocardial infarction and stroke. In the clinic endovascular procedures such as angioplasty are commonly performed to reopen the lumen. However, these treatments inevitably damage the vessel wall as well as the vascular endothelium, triggering an excessive healing response and the development of a neointimal plaque that extends into the lumen causing vessel restenosis (re-narrowing). Restenosis remains a major cause of failure of endovascular treatments for atherosclerosis. Thus, preclinical animal models of restenosis are vitally important for investigating the pathophysiological mechanisms as well as translational approaches to vascular interventions. Among several murine experimental models, femoral artery wire injury is widely accepted as the most suitable for studies of post-angioplasty restenosis because it closely resembles the angioplasty procedure that injures both endothelium and vessel wall. However, many researchers have difficulty utilizing this model due to its high degree of technical difficulty. This is primarily because a metal wire needs to be inserted into the femoral artery, which is approximately three times thinner than the wire, to generate sufficient injury to induce prominent neointima. Here, we describe the essential surgical details to effectively overcome the major technical difficulties of this model. By following the presented procedures, performing the mouse femoral artery wire injury becomes easier. Once familiarized, the whole procedure can be completed within 20 min.

The mouse femoral artery wire injury model of restenosis is technically challenging. In this protocol we show the key technical details essential for successfully performing wire injury to induce consistent&#160;neointima for studies of restenosis.

Um modelo murino de Arterial Restenosis: Aspectos Técnicos do Femoral Injury Fio

Cardiovascular disease caused by atherosclerosis is the leading cause of death in the developed world. Narrowing of the vessel lumen, due to ...

A Novel Murine Model of Arteriovenous Fistula Failure: The Surgical Procedure in Detail

The arteriovenous fistula (AVF) still suffers from a high number of failures caused by insufficient remodeling and intimal hyperplasia from which the exact pathophysiology remains unknown. In order to unravel the pathophysiology a murine model of AVF-failure was developed in which the configuration of the anastomosis resembles the preferred situation in the clinical setting. A model was described in which an AVF is created by connecting the venous end of the branch of the external jugular vein to the side of the common carotid artery using interrupted sutures. At a histological level, we observed progressive stenotic intimal lesions in the venous outflow tract that is also seen in failed human AVFs. Although this procedure can be technically challenging due to the small dimensions of the animal, we were able to achieve a surgical success rate of 97% after sufficient training. The key advantage of a murine model is the availability of transgenic animals. In view of the different proposed mechanisms that are responsible for AVF failure, disabling genes that might play a role in vascular remodeling can help us to unravel the complex pathophysiology of AVF failure.

Here we present a murine model of arteriovenous fistula (AVF) failure in which a clinically relevant anastomotic configuration is incorporated. This model can be used to study the pathophysiology and to test possible therapeutic interventions.

Um Modelo murino Novel de Fístula Arteriovenosa Falha: O procedimento cirúrgico em Detalhe

The arteriovenous fistula (AVF) still suffers from a high number of failures caused by insufficient remodeling and intimal hyperplasia from which the ...

Intraluminal Drug Delivery to the Mouse Arteriovenous Fistula Endothelium

Delivery of therapeutic agents to enhance arteriovenous fistula (AVF) maturation can be administered either via intraluminal or external routes. The simple murine AVF model was combined with intraluminal administration of drug solution to the venous endothelium at the same time as fistula creation. Technical aspects of this model are discussed. Under general anesthesia, an abdominal incision is made and the aorta and inferior vena cava (IVC) are exposed. The infra-renal aorta and IVC are dissected for clamping. After proximal and distal clamping, the puncture site is exposed and a 25 G needle is used to puncture both walls of the aorta and into the IVC. Immediately after the puncture, a reporter gene-expressing viral vector was infused in the IVC via the same needle, followed by 15 min of incubation. The intraluminal administration method enabled more robust viral gene delivery to the venous endothelium compared to administration by the external route. This novel method of delivery will facilitate studies that explore the role of the endothelium in AVF maturation and enable intraluminal drug delivery at the time of surgical operation.

After puncturing the aorta through the inferior vena cava (IVC) to create an aorto-caval fistula in the mouse, solution containing a drug is infused into the IVC via the same needle, followed by incubation. This method enables more robust drug delivery to the venous endothelium compared to the external route.

Drug Delivery intraluminal para o Rato Fístula Arteriovenosa endotélio

Delivery of therapeutic agents to enhance arteriovenous fistula (AVF) maturation can be administered either via intraluminal or external routes. The ...

Ultrasound Assessment of Endothelial Function: A Technical Guideline of the Flow-mediated Dilation Test

Cardiovascular disease is the primary cause of mortality and a major cause of disability worldwide. The dysfunction of the vascular endothelium is a pathological condition characterized mainly by a disruption in the balance between vasodilator and vasoconstrictor substances and is proposed to play an important role in the development of atherosclerotic cardiovascular disease. Therefore, a precise evaluation of endothelial function in humans represents an important tool that could help better understand the etiology of multiple cardio-centric pathologies.
Over the past twenty-five years, many methodological approaches have been developed to provide an assessment of endothelial function in humans. Introduced in 1989, the FMD test incorporates a forearm occlusion and subsequent reactive hyperemia that promotes nitric oxide production and vasodilation of the brachial artery. The FMD test is now the most widely utilized, non-invasive, ultrasonic assessment of endothelial function in humans and has been associated with future cardiovascular events.
Although the FMD test could have clinical utility, it is a physiological assessment that has inherited several confounding factors that need to be considered. This article describes a standardized protocol for determining FMD including the recommended methodology to help minimize the physiological and technical issues and improve the precision and reproducibility of the assessment.

The flow mediated dilation (FMD) test is the most commonly utilized, non-invasive, ultrasound assessment of endothelial function in humans. Although the FMD test has been related with the prediction of future cardiovascular disease and events, it is a physiological assessment with many inherent confounding factors that need to be considered.

Avaliação ultra-sons da função endotelial: A Orientação Técnica do Teste de dilatação fluxo-mediada

Cardiovascular disease is the primary cause of mortality and a major cause of disability worldwide. The dysfunction of the vascular endothelium is a ...

Murine Model of Central Venous Stenosis using Aortocaval Fistula with an Outflow Stenosis

Central venous stenosis is an important entity contributing to arteriovenous fistula (AVF) failure. A murine AVF model was modified to create a partial ligation of the inferior vena cava (IVC) in the outflow of the fistula, mimicking central venous stenosis. Technical aspects of this model are introduced. The aorta and IVC are exposed, following an abdominal incision. The infra-renal aorta and IVC are dissected for proximal clamping, and the distal aorta is exposed for puncture. The IVC at the midpoint between the left renal vein and the aortic bifurcation is carefully dissected to place an 8-0 suture beneath the IVC. After clamping the aorta and IVC, an AVF is created by puncturing the infra-renal aorta through both walls into the IVC with a 25 G needle, followed by ligating a 22 G intra-venous (IV) catheter and IVC together. The catheter is then removed, creating a reproducible venous stenosis without occlusion. The aorta and IVC are unclamped after confirming primary hemostasis. This novel model of central vein stenosis is easy to perform, reproducible, and will facilitate studies on AVF failure.

An aortocaval fistula was created by puncturing the murine infra-renal aorta through both walls into the inferior vena cava and was followed by creation of a stenosis in its outflow via partial ligation of the inferior vena cava. This reproducible model can be used to study central venous stenosis.

Modelo murino de estenose venosa central usando fístula Aortocaval com estenose de saída

Central venous stenosis is an important entity contributing to arteriovenous fistula (AVF) failure. A murine AVF model was modified to create a partial ...

Technical Detail for Robot Assisted Pancreaticoduodenectomy

Since its first report in 2003, robotic pancreaticoduodenectomy (RPD) has gained popularity among pancreatic surgeons. Inherent advantages of the robotic platform, including three-dimensional vision, wristed instruments, and improved ergonomics, allow the surgeon to recapitulate the principles of open pancreatoduodenectomy allowing safe oncologic dissection, hemostasis, and meticulous reconstruction. Over the course of the past decade, significant strides have been achieved in outlining the safety, feasibility, and learning curve of the robotic Whipple. When performed by high volume pancreatic surgeons experienced in RPD, recent comparative effectiveness studies show potential advantages compared to the open technique, including reductions in hospital stay and morbidity. National data also show reductions in conversion rates compared to its laparoscopic counterpart. Although long-term oncologic data are still needed, short-term oncologic surrogates of margin resection and lymph node harvest suggest no compromise in oncologic outcomes. As pancreatic surgeons increasingly integrate robotics into their practice, proficiency-based training and credentialing will be necessary for the safe application and dissemination of RPD. Here, we provide the detailed steps of a robotic pancreaticoduodenectomy performed at the University of Pittsburgh Medical Center.&#160;

The following manuscript details a stepwise approach to the robot-assisted pancreaticoduodenectomy performed at the University of Pittsburgh Medical Center.

Detalhe técnico para o robô ajudado Pancreaticoduodenectomy

Since its first report in 2003, robotic pancreaticoduodenectomy (RPD) has gained popularity among pancreatic surgeons. Inherent advantages of the robotic ...

Technical Modification of the Terminal Ureter During Total Transperitoneal Laparoscopic Nephroureterectomy for Upper Urinary Tract Urothelial Carcinoma

Upper tract urothelial carcinoma (UTUC) accounts for 5%&ndash;10% of all urothelial tumors. Radical nephroureterectomy is the standard treatment procedure. At present, different choices still exist for treating the ureteral end during laparoscopic ureteral bladder sleeve resection. Our center has adopted a new method for treating the ureteral end. This new method can increase the operating space and reduce the difficulty of the surgery compared with current methods.

Here, we present a protocol to increase the surgical field of view and reduce the difficulty of total transperitoneal laparoscopic nephroureterectomy surgery by precutting the umbilical ligament before treating the terminal ureter.

Modificação técnica do Terminal Ureter durante a Nefrologia Laparoscópica Total Transperitoneal para o Carcinoma Urotelial do Trato Superior

Upper tract urothelial carcinoma (UTUC) accounts for 5%&ndash;10% of all urothelial tumors. Radical nephroureterectomy is the standard treatment ...

Creating Radio-cephalic Arteriovenous Fistula in the Forearm with a Modified No-Touch Technique

Autologous arteriovenous fistula (AVF) is the primary and best option to obtain vascular access for hemodialysis treatment; other options are arteriovenous graft (AVG) and central venous catheterization (CVC). The implementation of radio-cephalic autologous arteriovenous fistula (RC-AVF) in the forearm was preferred among patients with superior vascular conditions. However, there is a high rate of early fistula failure. The chosen surgical method is understood to have an effect on the maturation of the fistula. New surgical procedures such as radial artery deviation and reimplantation (RADAR) have been significantly improved for juxta-anastomotic stenosis. Nevertheless, new problems such as stenosis of arteries and narrowing of surgical indication were also found. In this report, we presented a modified no-touch technique (MNTT) to create an RC-AVF, in which the venous and arterial wall avoid devascularization and the radial artery does not sever.

We present a modified no-touch technique (MNTT) to create a radio-cephalic arteriovenous fistula (RC-AVF) in which the venous and arterial wall avoid devascularization and the radial artery does not sever.