Ce travail a été financé en partie par l&#39;Institut national de la santé subvention R01-HL095498, ainsi que les ressources et l&#39;utilisation des installations du Connecticut Healthcare Système VA, West Haven, CT.

1. Procédures d&#39;anesthésie et pré-opératoire <ol><li> Induction de l&#39;anesthésie générale Approbation par l&#39;Institutional Animal Care appropriée et le Comité d&#39;utilisation est obtenue. Souris C57/black hommes, âgés de 10 semaines sont anesthésiés. Livrer 4% d&#39;isoflurane à 0,8 L / min d&#39;oxygène à une boîte en plexiglas via un vaporisateur isoflurane et placez la souris à l&#39;intérieur. Alternativement, si l&#39;on préfère par le chirurgien, anesthésie intrapéritonéale peut être utilisé. </li><li> Préserver l&#39;anesthésie Après confirmation de l&#39;anesthésie par le manque de réaction de pincement de l&#39;orteil, la souris est placé sur la table d&#39;opération en décubitus dorsal avec un masque de silicone. L&#39;isoflurane est réduite à 2% pour maintenir le niveau d&#39;anesthésie appropriée. </li><li> Épilation Cheveux ventrale est enlevé de la nuque au bas de l&#39;abdomen en utilisant un épilateur. solvant de cheveux est préférable parce que les cheveux qui est laissé à l&#39;aide d&#39;un rasoir peut interférer avec l&#39;échographie Doppler. </li></ol> 2. Ultrason préopératoired <ol><li> Objectifs de l&#39;échographie Échographie Doppler est effectué avant la chirurgie AVF afin d&#39;enregistrer les résultats de niveau de base qui peuvent être comparés avec les résultats post-opératoires à voir des changements anatomiques et physiologiques. </li><li> Points d&#39;observation La veine jugulaire, supra et infra-rénale veine cave inférieure (VCI), et de l&#39;aorte abdominale sont examinés en utilisant deux impulsions Doppler et B-mode. </li><li> Mesures En utilisant le mode B, le diamètre de chaque système vasculaire est mesurée. En outre, la vitesse maximale (pic de vélocité systolique dans les artères) et des formes d&#39;onde sont enregistrées dans chacun des points de mesure décrits ci-dessus. </li></ol> 3. Procédures opérationnelles <ol><li> Préparation de la souris Préparez le site d&#39;incision avec un antiseptique topique et continuer technique aseptique appropriée au cours de la chirurgie, y compris l&#39;aide d&#39;un drap chirurgical, gants et des instruments stériles, etc </li><li> Laparotomie Incision abdominale médiane est faite fROM bord inférieur du foie à juste au-dessus du pubis. </li><li> L&#39;exposition de l&#39;aorte et IVC. Un enrouleur est insérée et toutes les entrailles sont tirés hors de la cavité abdominale pour le côté droit et maintenu enveloppé dans de la gaze imbibée de sérum physiologique. Disséquer la membrane qui relie le rétropéritoine et inférieure du côlon pour obtenir la vue de l&#39;aorte et IVC. Appliquer une pression sur la vessie si elle est dilatée et se met en route. </li><li> L&#39;exposition du point de ponction site de ponction sera entre demi à trois quarts de la distance de la veine rénale gauche à la bifurcation aortique. (Figure 1) disséquer la marge gauche de l&#39;aorte de sorte qu&#39;il peut être perforé. Gardez à l&#39;esprit que l&#39;aorte est positionné sur 45 degrés derrière la VCI et il doit être disséqué arrière en plus vers la gauche. (Figure 2) Le point le plus important de cette chirurgie n&#39;est pas à disséquer entre l&#39;aorte et l&#39;IVC. Gardez loin d&#39;eux. </li><li> Exposition du site de fixation de l&#39;AORTA Disséquer l&#39;aorte sous-rénale à partir des tissus environnants. Attention à ne pas blesser l&#39;IVC sur les veines rénales droite et gauche avec ses affluents sur la droite. </li><li> Serrage de l&#39;aorte Fixer l&#39;aorte proximale en appliquant clips de microchirurgie. </li><li> Rotation de l&#39;aorte En saisissant le tissu conjonctif qui entoure l&#39;aorte, l&#39;aorte tourner de sorte que la perforation peut se faire d&#39;un côté légèrement dorsale de l&#39;aorte (figure 2). </li><li> Ponction de l&#39;aorte à travers IVC Garder l&#39;aorte dans une position de rotation, à la perforation de l&#39;aorte par le biais d&#39;IVC en utilisant une aiguille de calibre 25. (Figure 2) En cas de réussite, l&#39;aiguille peut être vu à travers la paroi mince IVC. </li><li> Hémostase En tirant les tissus rétropéritonéaux, y compris les muscles, enveloppez le site de ponction de l&#39;aorte. Ne pas comprimer l&#39;aorte contre l&#39;IVC, car il peut coaguler l&#39;AVF (Figure 3). </li><li> De-serrage de l&#39;aorte Après confirmationde l&#39;hémostase primaire, de-serrer l&#39;aorte. Saignement supplémentaire peut se produire, mais il peut être arrêté avec une compression supplémentaire décrit ci-dessus. Lors de-serrage, le sang artériel est visible circulant dans la veine cave inférieure à la place de l&#39;écoulement de sang veineux foncé. </li><li> Clôture de l&#39;abdomen Retourner les entrailles dans sa position naturelle et fermer l&#39;abdomen. </li></ol> 4. Procédures post-opératoires <ol><li> Les soins post-opératoires Après fermeture de l&#39;abdomen, de l&#39;isoflurane est arrêté. Les soins post-opératoires, notamment l&#39;analgésie et le soin des plaies est appliquée en conformité avec les instructions recommandées par le soin des animaux et du Comité institutionnel d&#39;utilisation. Pour l&#39;analgésie, nous utilisons la buprénorphine à 0,1 mg / kg toutes les intrasmuscularly h 12 à 24 h suivant les procédures chirurgicales. </li><li> Échographie post-opératoire Le premier jour après l&#39;opération, l&#39;échographie Doppler est effectuée pour confirmer l&#39;AVF. En outre, d&#39;autres variables sont mesurées pour vérifier les changements de pré-opératoirevaleurs. </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>

Il ya plusieurs rapports qui ont décrit AVF chez les rats, y compris AVF fémorale, 6, 7 carotide à jugulaire AVF 8 et aorto-cave AVF. 9, 10 Le rat est plusieurs fois plus grande que la souris, permettant de faciliter la chirurgie chez le rat par rapport à la souris. Néanmoins, afin de profiter des souches et des variantes génétiques de souris la procédure doit être étendue pour inclure des modèles de souris. Plusieurs rapports publiés précédemment introduit le modèle AVF c...

L&#39;option la plus commune choisie pour la thérapie de remplacement rénal chez les patients atteints d&#39;insuffisance rénale au stade ultime est l&#39;hémodialyse. Accès pour hémodialyse est effectuée par une fistule artério-veineuse (FAV), greffe artérioveineuse ou d&#39;un cathéter temporaire. Bien AVF sont le mode d&#39;accès privilégié, AVF sont encore loin d&#39;être parfait. Les taux de perméabilité primaire AVF d&#39;un an ne sont que 60-65%, avec de nombreux échecs dus à l&#39;hyperplasie intimale. La biologie moléculaire et la physiologie de la formation des AVF normale et la formation inadaptée restent mal caractérisés. En tant que tel, il ya beaucoup à gagner à l&#39;amélioration des résultats AVF avec le gain d&#39;accompagnement dans la compréhension de la régulation de la formation de la fistule. 1-3 L&#39;exposition d&#39;une veine de flux artériel est couramment étudiée dans le contexte des greffes de veine qui sont des modèles directs de pontage chirurgical. 4, 5 Bien que des greffons veineux et AVF exposent une veine similaire à un environnement artérielle, il ya plusieurs di critiquefferences entre eux. Tout d&#39;abord, la résistance du lit de ruissellement distale est beaucoup plus faible dans les AVF, comme l&#39;AVF draine vers l&#39;oreillette droite alors que la greffe de veine draine les petites artères distales souvent malades, ce qui augmente le flux sanguin et la contrainte de cisaillement dans l&#39;AVF. D&#39;autre part, le sang dans le membre veineux de la FAV peut être un mélange de sang veineux et artériel conduisant à une oxygénation plus faible par rapport à la teneur purement artérielle dans la greffe de veine. Troisièmement, la veine de l&#39;AVF n&#39;est pas sorti de son lit, ce qui conduit à la préservation de son vaso venorum et innervation nerveux, par rapport à la transposition complète de la greffe de veine dans le lit artériel. Enfin, le nombre d&#39;anastomoses est habituellement de deux à greffons veineux tandis qu&#39;une AVF a généralement qu&#39;une seule. Dans cette étude, nous présentons un modèle murin de la fistule aorto-cave qui peut être utilisé pour l&#39;étude de l&#39;AVF.

<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

Les aspects techniques de la création d&#39;une fistule artério-veineuse chez la souris sont discutées. Sous anesthésie générale, une incision abdominale est faite, et l&#39;aorte et la veine cave inférieure (VCI) sont exposés. L&#39;aorte sous-rénale proximale et distale de l&#39;aorte sont disséqués pour le placement de serrage et ponction à l&#39;aiguille, respectivement. Une attention particulière est accordée à éviter la dissection entre l&#39;aorte et la veine cave inférieure. Après serrage de l&#39;aorte, une aiguille 25 est utilisé pour perforer les deux parois de l&#39;aorte dans la veine cave inférieure. Le tissu conjonctif environnant est utilisée pour la compression hémostatique. La mise sur pied de l&#39;AVF montrera le flux sanguin artériel pulsatile dans la VCI. Une autre confirmation de AVF succès peut être atteint en post-opératoire échographie Doppler.

Après la pratique, la survie, le premier jour post-opératoire est généralement supérieur à 95%; au jour post-opératoire 7, la survie était de 91,3% figures 1 et 2 montrent le site de ponction idéal en vue coronale et transversale;. Placement de la ponction site est essentiel pour obtenir une bonne survie sans hémorragie excessive. Décès intra-opératoires et les décès post-opératoires précoces sont généralement dues à une hémorragie. Ceci tend à se produire avec dissection excessive...

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

Technical Aspects of the Mouse Aortocaval Fistula

L&#39;objectif est de produire une fistule artério-veineuse qui est simple et reproductible. Cette méthode n&#39;utilise pas de sutures adhésives ou de la colle. Par conséquent, les échantillons peuvent être utilisés avec la moindre quantité de matériaux étrangers à l&#39;analyse.

Aspects techniques de la fistule aorto-cave de la souris

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 vues.  Yale University. L'objectif est de produire une fistule artério-veineuse qui est simple et reproductible. Cette méthode n'utilise pas de sutures adhésives ou de la colle. Par conséquent, les échantillons peuvent être utilisés avec la moindre quantité de matériaux étrangers à l'analyse.

Vidéo: 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.

Microchirurgie veineuse Pouch artériel Bifurcation anévrismes dans le modèle du lapin: Aspects techniques

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

Recherche

Médecine

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.

Le lapin de sang-shunt modèle pour l&#39;étude de aiguë et les séquelles tardives de hémorragie méningée: Aspects techniques

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.

Un modèle murin de la resténose artérielle: les aspects techniques de fémur fil blessures

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.

A Novel modèle murin de la fistule artério-veineuse échec: la procédure chirurgicale en détail

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.

Intraluminale Drug Delivery à la souris fistule artério-endothélium

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.

Évaluation échographique de la fonction endothéliale: Une ligne directrice technique du Dilatation Test de débit à médiation

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.

Modèle murine de la sténose veineuse centrale utilisant la fistule d'Aortocaval avec une stenose sortante

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.

Détail technique pour robot assisté 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.

Modification technique de l'uretère terminal au cours du nephroureterectomie laparopique transpéritonéen total pour le carcinome urothélial des voies urinaires supérieures

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.