Surgical versus endovascular treatment of traumatic thoracic aortic rupture

ObjectivesBlunt traumatic thoracic aortic rupture is a life-threatening surgical emergency associated with high mortality and morbidity. The recent development of endovascular stent-graft prostheses offers a potentially less invasive alternative to open chest surgery, especially in patients with associated injuries. We sought to compare the results of conventional surgical repair and endovascular treatment of traumatic aortic rupture in a single center.MethodsFrom July 1998 to January 2004, 20 patients with acute blunt traumatic aortic rupture underwent treatment at our institution. All patients had a lesion limited to the isthmus, and associated injuries. Initial management included fluid resuscitation, treatment of other severe associated lesions, and strict monitoring of blood pressure. Eleven patients (9 men, 2 women; mean age, 32 years) underwent surgical repair, including direct suturing in 6 patients and graft interposition in 5 patients. Ten patients were operated on with cardiopulmonary support (left bypass with centrifugal pump, n = 2; extracorporeal circulation, n = 8). The delay between trauma and surgery was 2.6 days (range, 0-21 days). Nine patients (8 men, 1 woman; mean age, 32 years) underwent endovascular treatment with commercially available devices (Excluder, n = 2; Talent, n = 7). In all patients 1 stent graft was deployed. In 2 patients the left subclavian artery was intentionally covered with the device. The delay between trauma and endovascular treatment was 17.8 days (range, 1-68 days).ResultsOne patient in the surgical group (9.1%) died during the intervention. Three surgical complications occurred in 3 patients (27%), including left phrenic nerve palsy (n = 1), left-sided recurrent nerve palsy (n = 1), and hemopericardium 16 days after surgery that required a repeat intervention (n = 1). No patient in this group had paraplegia. In the endovascular group successful stent-graft deployment was achieved in all patients, with no conversion to open repair. No patient died, and no procedure-related complications, including paraplegia, occurred in this group. Control computed tomography scans obtained within 7 days after endovascular treatment showed exclusion of pseudoaneurysm in all cases. Length of follow-up for endovascular treatment ranged from 3 to 41 months (mean, 15.1 months). Computed tomography scans obtained 3 months after endovascular treatment showed complete disappearance of pseudoaneurysm in all patients.ConclusionIn the treatment of blunt traumatic thoracic aortic rupture, the immediate outcome in patients who receive endovascular stent grafts appears to be at least as good as observed after conventional surgical repair. Long-term follow-up is necessary to assess long-term effectiveness of such management

Horizon effects for surface waves in wave channels and circular jumps

Surface waves in classical fluids experience a rich array of black/white hole horizon effects. The dispersion relation depends on the characteristics of the fluid (in our case, water and silicon oil) as well as on the fluid depth and the wavelength regime. In some cases, it can be tuned to obtain a relativistic regime plus high-frequency dispersive effects. We discuss two types of ongoing analogue white-hole experiments: deep water waves propagating against a counter-current in a wave channel and shallow waves on a circular hydraulic jump.Comment: 4 pages, 2 figs. To appear in: Proceedings of the Spanish Relativity Meeting (ERE2010

Predictive model of a DBD lamp for power supply design and method for the automatic identification of its parameters

An electrical model for a dielectric barrier discharge(DBD) is proposed, with the aim of its application in power supply design process. An identification method, which finds the actual value of the parameters in a model, is presented. The specific modelling of a XeCl exciplex lamp is developed, along with the identification procedure of the parameters, using a sinusoidal and a pulsed experiment. Electrical representation of the model is done in two different simulators. The applicability of the identified model is proved with different experiments. Differences between experimental and simulated waveforms are minor, encouraging the use of the model in the construction of the converter for the DBD lamp

Evolution de la prise en charge des ruptures traumatiques de l'isthme aortique (à propos de 21 cas)

AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Contrôle du point de fonctionnement des décharges électriques par l'intermédiaire de leur alimentation

Le contrôle du point de fonctionnement des décharges électriques par leur alimentation est l'objet de cette étude. Les points de fonctionnement obtenus par le couplage de l'alimentation électrique et du dispositif de décharge peuvent être instables à cause du comportement dynamique de la décharge ou à cause d'une variation de sa longueur. Nous recherchons les différents couplages existant entre la décharge et les caractéristiques de son alimentation afin d'optimiser la conception et la commande de l'alimentation électrique pour favoriser le contrôle du point de fonctionnement. Dans cet objectif, on propose des modélisations analytiques et numériques du système qui permettent de simuler les couplages entre l'alimentation et la décharge. Cette approche est complétée par des investigations expérimentales qui permettent de considérer les cas de décharges pointe/pointe, des DBD et des décharges glissantes.The aims of this study is to control the operating point of electrical discharges. These points, resulting from the coupling between the power supply and its load, may be unstable because of the dynamic behaviour of the discharge or any change of its length. To optimize the design and the electronic control of the power supply, the couplings between the later and the discharge are prospected. Numerical and analytical models of the system are presented. These models can simulate the couplings between the power supply and a discharge and are used to achieve the design of the power supply and its control. This approach is completed by experimental investigations considering discharge between 2 points, glidarc and DBD.TOULOUSE-ENSEEIHT (315552331) / SudocSudocFranceF

Association de convertisseurs assurant une liaison énergétique

Associer des convertisseurs en électronique de puissance permet d'assurer l'échange entre deux sources d'énergies. C'est la nature des sources (courant, tension ou mixte) qui détermine le type de liaison entre les convertisseurs. Ensuite, pour la conception de la liaison, certaines règles fondamentales doivent être respectées, telle que la compatibilité des sources et de la liaison sur l'ensemble de l'horizon fréquentiel. Suivant la nature et les réversibilités des sources et de la liaison, les combinaisons sont multiples. Cet article détaille ainsi les principes de base à observer pour assurer des liaisons de convertisseurs efficaces. Les deux cas principaux de conversion à liaison intermédiaire sont également présentés : continue et alternative

Association de cellules de commutation : éléments de synthèse des convertisseurs statiques

La cellule de commutation est un organe de contrôle des transferts d’énergie, qui ne permet que l’interconnexion de dipôles assimilables à de sources de nature complémentaires. Afin de couvrir un ensemble plus large de cahiers des charges de conversion d'énergie électrique, sont étudiées les possibilités qu'offrent les associations de cellules de commutation. Les propriétés fonctionnelles, en particulier dans le domaine du réglage et dans celui de l'obtention de propriétés de réversibilité s’en trouvent élargies. Sont traitées des règles d'associations de cellules de commutation et le mécanisme par lequel des associations héritent des propriétés des cellules est présenté. Cependant, l’amélioration des performances en augmentant la puissance contrôlée ne peut se conduire que sous certaines précautions