Questo lavoro è stato sostenuto in parte dal National Institute of Health sovvenzione R01-HL095498, nonché con le risorse e l&#39;uso delle strutture del VA Connecticut Healthcare System di West Haven, CT.

1. Anestesia e pre-operatoria Procedure <ol><li> Induzione dell&#39;anestesia generale Approvazione da parte adeguata cura degli animali e del Comitato Istituzionale Usa si ottiene. Maschio topi C57/black, di 10 settimane, sono anestetizzati. Consegnare 4% isoflurano con 0,8 L / min di ossigeno per una scatola di plexiglas tramite un vaporizzatore isoflurano e posizionare il mouse all&#39;interno. In alternativa, se preferito dal chirurgo, anestesia intraperitoneale può essere utilizzato. </li><li> Preservare l&#39;anestesia Dopo la conferma di anestesia dalla mancanza di reazione alla punta pinch, il mouse viene messo sul tavolo operatorio in posizione supina con una maschera di silicone. Isoflurano è ridotta al 2% per mantenere adeguato il livello di anestesia. </li><li> Depilazione Capelli ventrale viene rimosso dal collo al basso addome usando un dispositivo di rimozione dei capelli. Rimozione dei capelli è preferito perché i capelli che viene lasciato utilizzando un rasoio può interferire con gli ultrasuoni Doppler. </li></ol> 2. Ultrasoun preoperatoriad <ol><li> Obiettivi del ultrasuoni Ecografia doppler viene eseguita prima dell&#39;intervento AVF modo da registrare le risultanze livello base che possono essere confrontati con i risultati post-operatori di vedere cambiamenti anatomici e fisiologici. </li><li> Punti di osservazione La vena giugulare, sovra-e infra-renale della vena cava inferiore (IVC) e aorta addominale vengono esaminati utilizzando sia Doppler impulso e B-mode. </li><li> Misurazioni Con la modalità B, diametro di ciascun vascolarizzazione viene misurato. Inoltre, massima velocità (velocità di picco sistolico in arterie) e le forme d&#39;onda vengono registrate in tutti i punti di misurazione sopra descritti. </li></ol> 3. Procedure Operative <ol><li> Topo Preparazione Preparare il sito di incisione con un antisettico topico e continuare una corretta tecnica asettica durante l&#39;intervento tra cui l&#39;uso di un telo chirurgico, guanti e strumenti sterili, ecc </li><li> Laparotomia Linea mediana incisione addominale è fatto from bordo inferiore del fegato a appena sopra il pube. </li><li> L&#39;esposizione dell&#39;aorta e IVC. Un divaricatore viene inserito e tutte le viscere sono tirati fuori dalla cavità addominale per il lato destro e mantenuto avvolto in una garza imbevuta con soluzione salina. Sezionare la membrana che collega il retroperitoneo e colon inferiore per ottenere pieno vista dell&#39;aorta e IVC. Applicare una pressione sulla vescica, se si dilata e si mette in cammino. </li><li> Esposizione del sito di puntura Sito di puntura sarà tra la metà a tre quarti della distanza dalla vena renale sinistra a biforcazione aortica. (Figura 1) sezionare il margine sinistro dell&#39;aorta modo che possa essere punta. Tenere presente che l&#39;aorta è posizionata circa 45 gradi dietro la IVC e deve essere sezionato posteriormente oltre alla sinistra. (Figura 2) Il punto più importante di questa chirurgia non è di sezionare tra l&#39;aorta e IVC. Tenere lontano da loro. </li><li> Esposizione del sito morsetto del aorta Sezionare l&#39;aorta sottorenale dai tessuti circostanti. Fare attenzione a non ferire l&#39;IVC sulle vene renale sinistra e di sinistra con i suoi affluenti di destra. </li><li> Bloccaggio della aorta Bloccare l&#39;aorta prossimale mediante l&#39;applicazione di clips di microchirurgia. </li><li> Rotazione della aorta Afferrando il tessuto connettivo circostante l&#39;aorta, ruotare l&#39;aorta in modo che la puntura può essere fatta dal lato leggermente dorsale dell&#39;aorta (Figura 2). </li><li> Puntura dell&#39;aorta attraverso di IVC Mantenendo l&#39;aorta in una posizione ruotata, l&#39;aorta mediante puntura di IVC utilizzando un ago G 25. (Figura 2) In caso di successo, l&#39;ago può essere visto attraverso la sottile parete IVC. </li><li> Emostasi Tirando i tessuti retroperitoneali, compresi i muscoli, avvolgere il sito di puntura dell&#39;aorta. Non comprimere l&#39;aorta contro la IVC, poiché potrebbero ostruire il AVF (Figura 3). </li><li> De-bloccaggio dell&#39;aorta Dopo la confermadella emostasi primaria, de-clamp dell&#39;aorta. Sanguinamento supplementare può accadere ma può essere fermata con un&#39;ulteriore compressione sopra descritto. Upon de-bloccaggio, sangue arterioso può essere visto scorre nel IVC anziché scuro flusso di sangue venoso. </li><li> Chiusura dell&#39;addome Riportare le viscere nella sua posizione naturale e chiudere l&#39;addome. </li></ol> 4. Procedure post-operatorie <ol><li> Assistenza post-operatoria Dopo la chiusura dell&#39;addome, isoflurano viene arrestato. Assistenza post-operatoria compresa l&#39;analgesia e la cura delle ferite è applicata in conformità con le istruzioni raccomandate da Institutional Animal Care e del Comitato Usa. Per l&#39;analgesia usiamo buprenorfina a 0.1 mg / kg intrasmuscularly ogni 12 ore per 24 ore seguendo le procedure chirurgiche. </li><li> Ecografia post-operatorio Il primo giorno dopo l&#39;operazione, Doppler è effettuata per confermare l&#39;AVF. Inoltre, altre variabili sono misurate per controllare i cambiamenti dal pre-operatoriavalori. </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>

Ci sono diversi rapporti che sono descritti AVF nei ratti, tra AVF femorale, 6, 7 carotidea a giugulare AVF 8 e aorto-cavale AVF. 9, 10 Il ratto è diverse volte più grande di quello del mouse, permettendo facile chirurgia nel ratto rispetto a il mouse. Tuttavia, al fine di usufruire di topo ceppi genetici e varianti la procedura deve essere estesa per includere modelli di mouse. Diversi rapporti precedentemente pubblicati introdotto il modello AVF nei topi, ma questi rapporti sono stat...

L&#39;opzione più comune scelto per la terapia sostitutiva renale in pazienti con malattia renale allo stadio terminale è l&#39;emodialisi. L&#39;accesso per l&#39;emodialisi viene eseguita da fistola artero-venosa (AVF), innesto arterovenose, o il posizionamento del catetere temporaneo. Sebbene AVF sono il modo preferito di accesso, AVF sono ancora ben lungi dall&#39;essere perfetto. Un anno primari tassi di pervietà AVF sono solo il 60-65%, con molti fallimenti dovuti a iperplasia della neointima. La biologia molecolare e fisiologia della formazione AVF normale e formazione disadattivi rimangono poco caratterizzati. Come tale, è molto da guadagnare nel miglioramento dei risultati AVF con il guadagno di accompagnamento nella comprensione del regolamento di formazione di fistole. 1-3 L&#39;esposizione di una vena di flusso arterioso è comunemente studiata nel contesto di innesti di vena che sono modelli diretti di bypass chirurgico. 4, 5 Sebbene innesti di vena e AVF similmente espongono una vena di un ambiente arterioso, ci sono diversi di criticafferences tra di loro. Prima, la resistenza del letto deflusso distale è molto inferiore nel AVF, come AVF drena all&#39;atrio destro mentre l&#39;innesto venoso drena alle malate spesso piccole arterie distali, con conseguente aumento del flusso sanguigno e shear stress nel AVF. Secondo, il sangue nell&#39;arto venoso del AVF può essere una miscela di sangue arterioso e venoso conseguente ossigenazione inferiore rispetto al contenuto puramente arteriosa nella innesto venoso. Terzo, la vena del AVF non viene rimosso dalla sua base, che porta alla conservazione del suo vaso venorum e innervazioni nervose, rispetto alla trasposizione completa dell&#39;innesto vena nel letto arterioso. Infine, il numero di anastomosi è di solito in due innesti di vena mentre una AVF ha tipicamente una sola. In questo studio, si introduce un modello murino di fistola aorto-cavale che può essere utilizzato per lo studio di 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

Sono discussi aspetti tecnici della creazione di una fistola artero nel topo. In anestesia generale, una incisione addominale è fatto, e l&#39;aorta e vena cava inferiore (IVC) sono esposti. L&#39;aorta sottorenale dell&#39;aorta prossimale e distale sono sezionati per il posizionamento e serraggio dell&#39;ago puntura, rispettivamente. Particolare attenzione è rivolta al fine di evitare la dissezione tra l&#39;aorta e la vena cava inferiore. Dopo aver fissato l&#39;aorta, un ago G 25 è usato per forare entrambe le pareti dell&#39;aorta nella IVC. Il tessuto connettivo circostante è utilizzato per la compressione emostatica. Realizzazione dello AVF mostrerà pulsatile del flusso di sangue arterioso nella IVC. Ulteriore conferma di AVF successo può essere ottenuto postoperatoria ultrasuoni Doppler.

Dopo la pratica, la sopravvivenza nel primo giorno post-operatorio è tipicamente superiore al 95%; al giorno post-operatorio 7, sopravvivenza era del 91,3% figure 1 e 2 mostrano il sito di puntura ideale in vista coronale e trasversale;. Posizionamento della puntura sito è fondamentale per ottenere una buona sopravvivenza senza eccessiva emorragia. Morti intra-operatorie e le morti precoci post-operatorie sono in genere a causa di emorragia. Ciò tende a verificarsi con eccessiva dissezione tra l&#39;...

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;obiettivo è di produrre una fistola artero che è semplice e riproducibile. Questo metodo non fa uso di suture o adesivi colla. Pertanto i campioni possono essere utilizzati con la minor quantità di materiali estranei per l&#39;analisi.

Aspetti tecnici della fistola aorto-cavale mouse

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 Views.  Yale University. L'obiettivo è di produrre una fistola artero che è semplice e riproducibile. Questo metodo non fa uso di suture o adesivi colla. Pertanto i campioni possono essere utilizzati con la minor quantità di materiali estranei per l'analisi.

Video: 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.

Microchirurgia arteriosa, venosa Pouch biforcazione aneurismi nel modello Rabbit: Aspetti Tecnici

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

Ricerca

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.

Il Coniglio Blood-shunt modello per lo studio di acuta e sequele tardive di emorragia subaracnoidea: Aspetti tecnici

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 modello murino di restenosi arteriosa: aspetti tecnici del femore Wire Injury

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 Modello murino di fistola artero-venosa Fallimento: la procedura chirurgica in dettaglio

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 per il mouse fistola artero-venosa endotelio

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.

Valutazione ecografica della funzione endoteliale: una Direttiva tecnica del test dilatazione flusso-mediata

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.

Modello Murine della Stenosi Venoso Centrale utilizzando Aortocaval Fistula con una stenosi di flusso

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.

Dettaglio tecnico per Robot Assistito 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.

Modifica tecnica del Terminal Ureter durante la Nefroroureterectomia laparoscopica transperitoneale per il carcinoma uroteliale superiore urinario

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.