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In this thesis, we report on the construction of an experiment aimed at trapping andcooling an ytterbium gaz, in order to realize artificial gauge fields. In the long term, thissetup will allow the study of strongly correlated quantum states which are atomic analogsof integer or fractional quantum Hall systems.We will first present the building of our experimental apparatus, and the optical coolingof ytterbium (174Yb). In particular, we will report on the design of a Zeeman slower,allowing for the direct loading of a magneto-optical trap operated on ytterbium’s intercombinationtransition 1S0 ! 3P1. The atomic cloud is then transported in an opticaldipole trap. A subsequent evaporative cooling stage results in the production of Bose-Einstein condensates of about 5 × 104 atoms.We then describe the construction of an ultra-narrow laser system at 578nm, able todrive ytterbium’s « clock » transition 1S0 ! 3P0. The laser frequency is stabilized using ahigh-finesse Fabry-Perot cavity, whose properties are precisely characterized in this work.Specifically, we present a method to calibrate the absolute frequency of the cavity bycomparison with an optical transition of molecular iodine.Finally, we show the results of spectroscopic measurements done on ytterbium condensatesusing the ultra-narrow laser. We also report on the coherent manipulation of thecondensate on the clock transition, consisting in the observation of Rabi oscillations.These preliminary experiments should allow for a measurement of ytterbium’s scatteringproperties.Keywords : cold atoms, optical lattices, Bose-Einstein condensates, ultra-stable lasers,clock transition, quantum simulation.; Dans cette thèse, nous faisons état de la construction d’un dispositif expérimentalcapable de piéger et refroidir un gaz d’ytterbium, dans l’optique de simuler des champsmagnétiques artificiels. Ce dispositif permettra, à terme, de produire et de caractériserdes états quantiques fortement corrélés, semblables aux états rencontrés dans la physiquede l’effet Hall quantique, entier ou fractionnaire.Dans un premier temps, nous décrivons la construction des parties de notre dispositifconsacrées au refroidissement optique de l’ytterbium (174Yb). En particulier, nousprésentons la conception d’un ralentisseur Zeeman, permettant le chargement direct d’unpiège magnéto-optique effectué sur la transition d’intercombinaison 1S0 ! 3P1 de l’ytterbium.Après transport dans un piège optique, une étape de refroidissement évaporatifnous permet d’obtenir des condensats de Bose-Einstein contenant environ 5×104 atomesd’ytterbium. Les condensats produits sont alors chargés dans un réseau optique verticalà la longueur d’onde « magique ».Nous présentons ensuite la construction d’un système laser étroit à 578nm capabled’exciter la transition « d’horloge » 1S0 ! 3P0 de l’ytterbium. Le laser est asservi surune cavité Fabry-Perot de grande finesse servant de référence de fréquence, dont nousavons caractérisé les différentes propriétés. Nous présentons en particulier une méthodepermettant de calibrer rapidement la fréquence absolue de la cavité par comparaison avecune transition de la molécule de diiode.Finalement, nous présentons les résultats d’expériences de spectroscopie effectuées surdes condensats d’ytterbium à l’aide du laser étroit, ainsi que la manipulation cohérentedu condensat sur la transition d’horloge au cours d’expériences d’oscillations de Rabi. Cesexpériences préliminaires ouvrent notamment la voie à la mesure des propriétés colisionnellesde l’ytterbium 174.

Resume Il s'agit d'un patient de 52 ans, de classe ASA 3–4, denutri et ethylotabagique presentant une bronchopathie chronique obstructive et une cirrhose, ayant eu dans les suites operatoires d'une chirurgie carcinologique cervicale une pneumopathie d'inhalation ayant entrainee le deces en reanimation par decompensation hepatique. Compte tenu du terrain et des imperatifs chirurgicaux, cette infection qualifiee de nosocomiale, semblait difficilement evitable. Les multiples facteurs de risque, les rares mesures preventives utilisables et la jurisprudence actuelle ont ete analyses. Dans ce contexte, la tendance mediatique et judiciaire a rendre les medecins responsables des infections nosocomiales devrait etre revisee.

International audience; We describe Doppler spectroscopy of Bose-Einstein condensates of ytterbium atoms using a narrow optical transition. We address the optical clock transition around 578 nm between the ${^1}S_0$ and ${^3}P_0$ states with a laser system locked on a high-finesse cavity. We show how the absolute frequency of the cavity modes can be determined within a few tens of kHz using high-resolution spectroscopy on molecular iodine. We show that optical spectra reflect the velocity distribution of expanding condensates in free fall or after releasing them inside an optical waveguide. We demonstrate sub-kHz spectral linewidths, with long-term drifts of the resonance frequency well below 1 kHz/hour. These results open the way to high-resolution spectroscopy of many-body systems.

Resume Objectifs Evaluer l’efficacite analgesique du bloc sciatique en medecine prehospitaliere lors des traumatismes graves de la jambe ou du pied. Patients et methodes Etude retrospective, monocentrique portant sur la periode 1998–2008. Resultats Vingt-trois blocs sciatiques ont ete colliges, cinq par voie haute et 18 par voie basse (poplitee laterale) dont 14 sans neurostimulateur. La decroissance de la douleur evaluee par EVS a T0 (avant bloc), T1 (dix minutes apres bloc) et T2 (arrivee aux urgences), s’est revelee significative, quels que soient les intervalles de mesure (T0–T1, T0–T2, T1–T2), les voies d’abord utilisees et les anesthesiques locaux administres. L’installation de l’analgesie a ete plus rapide lors des approches du nerf sciatique par voie haute et lors de l’utilisation d’un neurostimulateur. Un seul echec analgesique a ete observe lors de la realisation d’un bloc sciatique par voie poplitee laterale sans neurostimulateur. Aucune complication n’a ete rapportee. Conclusion Le bloc sciatique realise en situation prehospitaliere presente une efficacite analgesique significative qui pourrait meriter de plus vastes evaluations et une reflexion sur son introduction dans l’arsenal therapeutique des medecins urgentistes.

Resume Les auteurs decrivent une cure chirurgicale de hernie ombilicale etranglee realisee en urgence au moyen d’une anesthesie par bloc paraombilical associe a une infiltration locale. Chez ce patient ASA 3–4, cirrhotique, en occlusion avec vomissements iteratifs et trouble de l’hemostase, la realisation d’une anesthesie generale ou rachidienne semblait a tres hauts risques. Le bloc paraombilical, utilise parfois pour l’anesthesie et/ou l’analgesie perioperatoire de la chirurgie reglee de la hernie ombilicale, surtout chez l’enfant, a permis la realisation de l’acte operatoire dans de bonnes conditions et a procure une analgesie postoperatoire de longue duree. Ce bloc, de realisation facile, est une alternative interessante en situation d’urgence chez le patient a risques pour l’anesthesie generale ou rachidienne.

Just as readers feel immersed when the story line adheres to their experiences, users will more easily feel immersed in a virtual environment if the behavior of the characters in that environment adheres to their expectations, based on their life-long observations in the real world. This paper introduces a framework that allows authors to establish natural, human-like behavior, physical interaction and emotional engagement of characters living in a virtual environment. Represented by realistic virtual characters, this framework allows people to feel immersed in an Internet based virtual world in which they can meet and share experiences in a natural way as they can meet and share experiences in real life. Rather than just being visualized in a 3D space, the virtual characters (autonomous agents as well as avatars representing users) in the immersive environment facilitate social interaction and multi-party collaboration, mixing virtual with real.

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The authors describe a strangulated umbilical hernia surgery performed in emergency with a paraumbilical block associated with a local infiltration. For this patient, 3-4 ASA status, in occlusion, with iterative vomiting and coagulation disorders, general or spinal anaesthesia were high-risk technics. Paraumbilical block, sometimes used for anaesthesia or/and analgesia for programmed umbilical hernia surgery, allowed surgery with good conditions and procured prolonged postoperative analgesia. This block, easy to perform, is an interesting alternative in emergency for general or spinal anaesthesia in high-risk patients.

We report the case of a 52-year-old man, ASA 3-4, malnourished, heavy smoker and drinker at the stage of chronic obstructive pulmonary disease and cirrhosis. The postoperative course of a cervical cancer surgery was complicated by a pneumonia with fatal outcome in the intensive care unit. Taking into account the patient's history and surgical requirements, this nosocomial infection did not appear easily preventable. The multiple risk factors and the few preventive measures usable were analyzed. In this context, the media and legal trend to make the doctors responsible for the nosocomial infections should be revised.

The purpose of this study was to evaluate the efficacy and safety of episcleral single-injection anesthesia in a large number of patients.Over a period of 5 yr, in four institutions, anesthesiologists involved in this prospective study completed a standardized form to evaluate single-injection medial canthus high-volume episcleral anesthesia. The success rate of the block was rated according to an akinesia score. The study parameters included demographic data, surgical procedure, and anesthetic management. All patients were followed up at least until postoperative day 1, and all complications, pain, and discomfort were noted. Statistical analysis was done to assess the risk factors for complications.A total of 2,031 patients were included in the study. The most frequent surgical procedures performed were phacoemulsification and posterior chamber artificial lens implantation (91.0%). A total of 66 complications (3.3%) occurred in 60 patients. One patient had a retrobulbar hemorrhage, and 59 had one or two more minor incidents or pain/discomfort with the procedure. The complications consisted of subconjunctival hematoma (1.3%), ocular hypertonia (0.4%), and chemosis (0.30%). Statistical analysis revealed that inexperience in the technique represented a risk factor for complications.This is the first survey of a large experience in episcleral single-injection anesthesia, a form of anesthesia that does not preclude sharp-needle complications and does require training. Only one complication occurred among 2,031 patients; however, a larger number of patients is needed to definitively evaluate the safety of episcleral single-injection anesthesia.

Medial canthus episclera (sub-Tenon's) anaesthesia is a technique proposed as a suitable alternative to the more classical peribulbar block because of the greater reliability and more constancy in effectiveness. We report two cases of retrobulbar haematoma after sub-Tenon's anaesthesia, one with central retina artery compression needed anterior room punction. Sub-Tenon's anaesthesia, like peribulbar anaesthesia, can give also retrobulbar haemorrhage if the insertion of the needle is not limited to the anterior orbit.

Background: Favourable outcome of phaeochromocytoma surgery requires that paroxysmal hypertension and arrhythmia be controlled, and that hypotension be prevented. Is nicardipine, a calcium channel blocking drug, always adequate? Methods: Nineteen consecutive patients underwent surgery for phaeochromocytoma. Management was standardised with regards to anaesthesia and antihypertensive treatment. Nicardipine was used as a vasodilator and was given in order to maintain systemic vascular resistance lower than 1600 dyn · s · cm−5. Results: Hypertension did not occur at any time during surgery in 6/19 patients. Blood pressure rose acutely in 3/19 patients at the time of tracheal intubation or surgical approach to the tumour, and was controlled by increased depth of anaesthesia. Hypertensive episodes occurred in 11/19 patients during tumour manipulation. Nicardipine always succeeded in maintaining low systemic vascular resistance but its dosage varied widely between patients (0.5 to 70 mg), a fact that may be accounted for by the striking intersubject variability of haemodynamic behaviour during surgery. In 7/11 patients, despite nicardipine treatment, sustained increase in blood pressure persisted with increased cardiac index, but low systemic vascular resistance. Following tumour removal, transient serious hypotension (MAP

Surgical rehabilitation of the upper limb in quadriplegia aims to restore prehension function. Surgical restoration always involves active extension of both elbow and wrist. Anesthesia, which first aim is to allow adequate surgical conditions, must adapt to the patient's disability. In this particular setting, regional anesthesia and especially brachial plexus block techniques represents our priority choice.