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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Validation clinique et métabolique de l'approche endoscopique par notes de la chirurgie bariatrique sur modèle porcin vivant / Clinical and metabolic validation of surgical endoscopic approach using notes for bariatric surgery on living swine model

Vanbiervliet, Geoffroy 18 December 2015 (has links)
Introduction – Le but de ce travail était de développer un modèle expérimental endoscopique de chirurgie bariatrique par technique NOTES, simple, reproductible et de le valider à la fois sur le plan clinique (faisabilité, tolérance) et sur le plan métabolique (physiopathologie et mode d’action). Matériels et méthodes - Les études furent menées au sein du CERC et de l’unité INSERM UMRS 1260. L’animal étudié fut le cochon domestique, âgé de 3 à 4 mois, sains et non obèse. Les endoscopies étaient réalisées à l’aide d’un gastroscope double canal opérateur et de matériel d’endoscopie couramment disponible. Plusieurs étapes de développement furent mises en place de la confection d’un modèle animal d’anastomose gastro-jéjunale par technique endoscopique NOTES exclusive à l’évaluation de l’impact métabolique d’un modèle de by-pass gastrique à visée bariatrique utilisant l’anastomose gastro-jéjunale par apposition prothétique luminale. Résultats – Le modèle d’anastomose gastro-jéjunale choisi pour sa faisabilité et son innocuité fut développé par apposition des lumières digestives gastriques et grêliques avec prothèse en technique NOTES trans digestive. L’évaluation métabolique expérimentale du by-pass gastrique utilisant ce mode opératoire permit de constater une amélioration significative de l’insulino-résistance non véhiculées par le GLP-1. Conclusion – Le concept d’anastomose digestive par NOTES exclusive et apposition luminale prothétique est établi et le modèle de by-pass endoscopique utilisant ce mode opératoire est faisable semblant présenter un impact métabolique significatif. / Introduction - The aim of this study was to develop an endoscopic experimental model of NOTES bariatric surgery using a simple, reproducible technique and to validate it both clinically (feasibility, tolerance) and metabolically (pathophysiology and action plan). Materials and Methods - The studies were conducted within the CERC and INSERM UMRS 1260 unit. The animal was the pig, aged 3 to 4 months, healthy and not obese. Endoscopies were performed using a dual channel gastroscope operator and the endoscopy equipment currently available. Several development stages were set up from the development of an animal model of gastrointestinal anastomosis using an exclusive endoscopic NOTES procedure to the evaluation of the metabolic impact of gastric bypass bariatric model described using the gastrointestinal anastomosis by luminal apposing stent technique. Results - The gastro-jejunal anastomosis model chosen for its feasibility and safety was developed by luminal apposing gastric and small bowel digestive lumens with a specific metallic covered stent and NOTES technique. The experimental evaluation of the metabolic gastric bypass using this procedure allowed to observe a significant improvement in insulin resistance none mediated by GLP-1 and incretin effect. Conclusion - The concept of anastomosis with luminal apposing stent and exclusive NOTES technique is established and endoscopic bypass model using this procedure is feasible pretend to present a significant metabolic impact.
132

Anestesisjuksköterskans åtgärder inför den postoperativa vården : En journalgranskningsstudie med fokus på smärta, illamående och vårdtid hos patienter som genomgått Gastric Bypass-operationer

Pettersson, Nils, Häggström, Matilda January 2017 (has links)
Bakgrund: Nästan hälften av alla vuxna svenskar är överviktiga eller lider av fetma vilket tillsammans med dess följdsjukdomar kostar samhället flera miljarder kronor per år. Trots att behandlande överviktsoperationer (främst gastric bypass [GBP]) blir allt vanligare i Sverige, är patientens hälsotillstånd intra-, och postoperativt relativt outforskat vad gäller smärta, postoperativt illamående och kräkning [PONV], vårdtid samt det ökande lidandet detta medför.   Syfte och Metod: Syftet är att beskriva mängden analgetika och antiemetika som ges till patienter som genomgår GBP-operationer, från premedicinering till utskrivning på den postoperativa vårdavdelningen. Vidare undersöks om anestesisjuksköterskan positivt kan påverka den postoperativa vården med avseende på smärtlindring, PONV och vårdtid då detta kopplas till lidande. En kvantitativ deskriptiv retrospektiv journalgranskningsstudie gällande totalt 68 patienter genomfördes.   Resultat: Gavs lokalanestetika i operationssåret under operation minskade både behovet av analgetika postoperativt (p<0,05) och den postoperativa vårdtiden (p<0,05). Om antiemetika gavs intraoperativt minskade användningen av antiemetika postoperativt (p<0,001). Ju större dos antiemetika/kg/min som gavs intraoperativt desto kortare tid på den postoperativa vårdavdelningen (p<0,001). Detta gällde oavsett om patienten fått lokalanestetika (p<0,01) eller inte (p<0,05).   Slutsats: Anestesisjuksköterskan har stora möjligheter att på flera plan positivt påverka tiden direkt efter operation. Intraoperativ administrering av lokalanestetika och antiemetika har avgörande roller för den fortsatta vården hos patienter som genomgår GBP-operationer, både vad gäller smärta, PONV, vårdtid och det lidande som detta kan medföra. Antiemetika doseras till synes enligt rutin och inte i förhållande till vikt, men ger viktberoende effekter. Mer forskning inom området efterfrågas. / Objectives: Almost 50 % of Swedish adults are overweight or obese, which costs the society billions annually. Although surgical treatments of obesity (primarily gastric bypass [GBP]) are increasing in Sweden, the patient's perioperative health status are relatively unexplored in terms of pain, postoperative nausea and vomiting [PONV], length of postoperative observation ward [POW] stay and the increasing suffering this entails. The authors aim to describe the amount of perioperative analgesics and antiemetics that GBP patients receive, and investigate how the nurse anesthetist can affect the postoperative care. Method: A quantitative descriptive retrospective study with a total of 68 patients was conducted. Result: The need for postoperative analgesics (p<.05) and the length of stay in the POW (p<.05) were both reduced whenever local anesthetics were given during surgery. If antiemetics were given intraoperatively, the use of antiemetics postoperatively was reduced; (p<.001). A greater intraoperative dose antiemetic/kg/minute reduced the length of stay in the POW (p<.001) regardless whether the patients received local anesthetics (p<.01) or not (p<.05). Conclusion: The nurse anesthetist can positively impact the immediate time after surgery. Intraoperative administration of  antiemetics and local anesthetics have crucial roles for the continued care of the GBP patient in terms of suffering connected to pain, PONV and length of stay in the POW. Antiemetics are seemingly dosed based on a routine and not on the patient's weight. More research in this area are requested.
133

Avaliação dos níveis plasmáticos de IGF-1, glicose e insulina no pré e pós-operatório de pacientes submetidos à cirurgia de Fobi-Capella

Lima, Paulo Autran Leite 27 June 2007 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / La investigación evaluó el comportamiento de los niveles plasmáticos de IGF-1, glucosa e insulina en el pre y post operatorio de pacientes sometidos a la cirugía de Fobi Capella. Ese estudio fue descriptivo y transversal, con evaluación de muestra sanguínea de 45 individuos. Los pacientes fueron divididos en 4 grupos: No obesos, Pre operatorio, Post operatorio 45 días y Post operatorio 1 año; pareados por la edad, altura y sexo, siendo analizados IMC, peso, IGF-1, glucosa, insulina basal, escore de IGF-1 y HOMA-IR. Fue observado que el promedio de peso y de IMC redujeron significativamente tras un año de cirugía bariátrica (55% y 42, 16%, respectivamente). Los niveles de IGF-1 estuvieron más bajos en los obesos cuando comparados a los eutróficos, tras 45 días de cirugía hubo caída adicional de 30, 1% (197, 15 ± 71, 74 ng/mL para 137,82 ± 86,48 ng/mL) y pacientes con un año de post operatorio presentaron promedio semejante al de los no obesos (251,50 ± 98,72 ng/mL y 329,09 ± 89,83 ng/mL). El escore de IGF-1 siguió las tendencias observadas anteriormente. Los valores glicémicos en los post operatorios, 45 días (86,18 ± 8,53 mg/dL) y 1 año (82,50 ± 9,19 mg/dL), fueron inferiores a los de pre operatorio (94,54 ± 23,70 mg/dL) y los grupos de 1 año y no obesos fueron semejantes. El promedio de insulina en pacientes con 45 días (9,26 ± 4,86uU/mL) y un año (6,71 ± 4,41uU/mL) de post operatorio fue menor que el resultado encontrado en el pre operatorio (62,56 ± 47,53uU/mL) y semejantes al del no obeso. El HOMA-IR redujo 82,6% y 88,78% en los grupos post operatorios con relación al pre. Esos datos sugieren que la cirugía de Fobi-Capella tiende a normalizar los parámetros estudiados. / A pesquisa avaliou o comportamento dos níveis plasmáticos de IGF-1, glicose e insulina no pré e pós-operatório de pacientes submetidos à cirurgia de Fobi-Capella. Esse estudo foi descritivo e transversal, com avaliação da amostra sangüínea de 45 indivíduos. Os pacientes foram divididos em 4 grupos: Não-obesos, Pré-operatório, Pós-operatório 45 dias e Pós-operatório 1 ano; pareados pela idade, altura e sexo, sendo analisados IMC, peso, IGF-1, glicose, insulina basal, escore de IGF-1 e HOMA-IR. Foi observado que a média do peso e do IMC reduziram significativamente após um ano de cirurgia bariátrica (55% e 42,16%, respectivamente). Os níveis de IGF-1 estiveram mais baixos nos obesos quando comparados aos eutróficos; após 45 dias de cirurgia houve queda adicional de 30,1% (197,15 ± 71,74ng/mL para 137,82 ± 86,48ng/mL) e; pacientes com um ano de pós-operatório apresentaram média semelhante a de não-obesos (251,50 ± 98,72ng/mL e 329,09 ± 89,83ng/mL). O escore de IGF-1 seguiu as tendências observadas anteriormente. Os valores glicêmicos nos pós-operatórios, 45 dias (86,18 ± 8,53mg/dL) e 1 ano (82,50 ± 9,19mg/dL), foram inferiores aos de pré-operatório (94,54 ± 23,70mg/dL) e os grupos de 1 ano e não-obesos foram semelhantes. A média de insulina em pacientes com 45 dias (9,26 ± 4,86uU/mL) e um ano (6,71 ± 4,41uU/mL) de pós-operatório foi menor que o resultado encontrado no pré-operatório (62,56 ± 47,53uU/mL) e semelhantes a de não-obeso. O HOMA-IR reduziu 82,6% e 88,78% nos grupos pós-operatórios com relação ao pré. Esses dados sugerem que a cirurgia de Fobi-Capella tende normalizar os parâmetros estudados.
134

Efeito do exercício físico aeróbio em mulheres submetidas à gastroplastia Bypass y de Roux / Effect of aerobic exercise in women undergoing gastric Bypass Roux-em-y

Marcela Grisólia Grisoste Zwarg 04 May 2010 (has links)
O presente estudo avaliou o efeito do exercício aeróbio em mulheres obesas, pós gastroplastia Bypass Y de Roux. Dentre os objetivos específicos, comparou o percentual de gordura por dobras cutâneas, antes e após o programa de treinamento e o peso corporal em Kg pré e pós intervenção. A amostra foi composta por 11 mulheres com média de 31,45 anos (± 8,27) e a altura de 1,63 metros (± 0,03), durante 12 semanas, realizaram 60 minutos de exercício físico aeróbio (caminhada/corrida), 5 vezes na semana, com FC controlada. A média da prescrição da FCM foi entre 142,18 bpm (± 2,63) e 157,90 bpm (± 3,41), correspondendo a 55 e 70% da FCM. Antes do início e após o término do programa de treinamento, foi avaliado o método duplamente indireto de composição corporal. Dentre as medidas antropométricas foram coletadas a estatura; o peso; as circunferências e as dobras cutâneas. A análise dos dados foi realizada pelo programa estatístico SPSS versão 16.0. Os resultados da estatística descritiva foram expressos como média e desvio padrão (± dp) e, em todas as análises, foi adotado como nível de significância p<0,05. A adesão ao programa de exercício físico aeróbio durante 12 semanas foi um procedimento eficaz e significante para a redução do peso corporal, para o IMC, as circunferências de cintura e quadril, o RCQ e para o percentual de gordura corporal. Foi possível obter um efeito significativo na composição corporal, apesar de não se ter controlado outros tratamentos convencionais, tais como hábitos nutricionais, medicamentosos e terapias comportamentais / This study has evaluated the effect that aerobic exercise has in obese women after the gastric bypass Y de Roux Amongst the specific objectives, it compared the fat percentage by skinfold thickness before and after the training program and the body weight in kilograms before and after intervention The sample was built of 11 women of 31,45 years old (± 8,27) on average and heights of 1,63 (± 0,03) on average on a 12 Week period they performed 60 minutes of aerobic exercise (walking, running) 5 times a week with heart rate controlled. The average of the FCM prescription was between 142,18 bpm (± 2,63) and 157,90 bpm (± 3,41) equivalent to 55 and 70% of FCM Before the beginning and after the end of the training program they assessed the double indirect method of body composition. Amongs the anthropometric measures they collected data as tallness, weight, circumference, and skinfolds. The data analysis was accomplished by the statistics program SSPS version 16.0 The results from the descriptive statistics were expressed as average and standard deviation (± SD) and for all the analysis the significance level used was p<0,05 he adhesion to the aerobic exercise program. The adhesion on a 12-week period was an efficient and significant procedure to body weight loss to the IMC to waist and hip circumference the RCQ and to the percentage of body fat It was possible to obtain a significant effect on the body composition, despite not having checked other conventional treatments such as nutritional habits, drugs and behavioral therapies
135

Gastric bypasskirugi : patientupplevelser ur psykosocialt och krppsligt perspektiv / Gastric bypass surgery : patient experinces of psychosocial and physical perspective

Karlsson, Anne-Marie, Nilsson, Maria January 2013 (has links)
Fetma är ett av de allvarligaste hälsoproblemen i världen. Övervikt i såväl ungdomen och vuxenlivet är associerad med en ökad dödlighet. Bestående viktminskning minskar risken att dö i förtid. Gastric Bypass är en kirurgi som hjälper personer med fetma till viktminskning och ger ett minskat näringsupptag. Syftet var att belysa personers psykosociala och kroppsliga upplevelser efter en gastric bypass operation. Arbetet är utformat som en litteraturstudie och baseras på tio kritiskt granskade kvalitativa och kvantitativa artiklar, efter genomläsning och analys tydliggjordes fyra kategorier. I resultatet identifierades fyra huvudteman efter genomgången gastric bypass kirurgi. Det som beskrivs är: känslomässiga förändringar, kontroll över födointag, livskvalité vid kroppsförändringar samt upplevelser i olika relationer. Slutsatsen visar att den upplevda livskvalitén förbättrades eller var god även om undantag sågs. / Obesity is one of the most serious health problems in the world. Obesity in both adolescence and adulthood is associated with increased mortality. Permanent weight loss reduces the risk of dying prematurely. Gastric bypass is a surgery that helps obese people to lose weight and provides a reduced nutrient intake. The aim was to highlight people's psychosocial and physical sensations after gastric bypass surgery. The work is designed as a literature review and based on ten critically examined qualitative and quantitative articles. Analysis of the literature identified four major themes resulting from the completion of gastric bypass surgery. These can be described as: emotional changes, control of food intake, quality of life resulting from body changes and experiences in different relationships. The conclusion shows that the perceived quality of life was improved or was good, although there were exceptions.
136

Studies on the inotropic effect of insulin and glucose : a new diet for the ischemic heart?

Carvalho, George. January 2007 (has links)
No description available.
137

Anatomische Voraussetzungen für pedale Bypass-Revaskularisationen

Wacker, Anne 26 January 2012 (has links) (PDF)
Zusammenfassung Gefäßerkrankungen und Diabetes mellitus nehmen als Krankheiten der modernen Zivilisation zu. Sie gehen oft mit dem Risiko einer Amputation einher. Trotz verbesserter Therapie aufgrund des medizinischen Fortschritts steigen die Amputationsraten. Besonders gefährdet sind Patienten mit Diabetes mellitus. Aufgrund des besonderen Atherosklerosebefallsmusters mit Verschluss der kruralen Gefäße bei relativer Aussparung der Oberschenkel- und Fußarterien erzielen pedale Bypässe bei diabetischen Patienten besonders gute Ergebnisse im Hinblick auf die Wiederherstellung der Fußdurchblutung. Ein pedaler Bypass kann eine drohende Amputation oft verhindern. Voraussetzungen für eine pedale Bypass-Operation sind umfassende anatomische Kenntnisse über die Variabilität der Arterien im Operationsgebiet. Die vorliegende Arbeit befasst sich mit den Gefäßvariationen an Unterschenkel und Fuß. Mit unterschiedlichen Methoden wurden Alkohol-fixierte (n=12) und Thiel-fixierte (n=10) Beinpräparate auf arterielle Variabilität untersucht. Die Alkohol-fixierten Präparate wurden makroskopisch präpariert und fotografisch dokumentiert, außerdem erfolgte eine Probenentnahme zur histologischen Untersuchung der Atherosklerosegrade in verschiedenen Gefäßregionen (n=32) und die Herstellung von zwei Dauerpräparaten. An Thiel-fixiertem Material wurde die Digitale Subtraktionsangiographie (DSA) getestet. Folgende Fragestellungen waren zu beantworten: 1. Welche Variationen der Blutgefäße finden sich für den Unterschenkel und Fuß? Wie kommunizieren die Gefäße zwischen Fußsohle und Fußrücken? 2. Wie können kleinste Gefäße am Fuß präpariert und fotografisch dokumentiert werden? 3. Lässt sich an fixiertem Leichenmaterial eine Digitale Subtraktionsangiographie durchzuführen? 4. Zeigen proximale und distale Blutgefäße des Beines einen unterschiedlichen Befall der Atherosklerose? 5. Welche Bedeutung hat die Herstellung von Dauerpräparaten für den studentischen Unterricht? 6. Welche Bedeutung hat die makroskopische Anatomie für die Klinik? Die Ergebnisse und Schlussfolgerungen sind: 1. Während der makroskopischen Präparation fanden sich folgende Variationen: Trifurkation, Truncus tibiofibularis anterior mit hohem Abgang der A. tibialis posterior und Abgang der A. tibialis anterior aus der A. fibularis, eine sehr dominante A. fibularis bei schwach ausgeprägter A. tibialis posterior, ein Arcus plantaris durch den zweiten intermetatarsalen Spalt laufend, kräftig ausgebildete A. plantaris profunda, kräftiger tiefer Ast der A. plantaris medialis, stark ausgeprägte A. arcuata. Die den Arcus plantaris versorgenden Arterien, vor allem die A. plantaris lateralis und die A. plantaris profunda, variieren stark in ihrer Ausprägung. Sie sind Teil der „Ringanastomose”, die eine Durchblutung des Fußes über die Verbindungen verschiedener Gefäße zwischen Fußsohle und Fußrücken gewährleistet. Neben der A. plantaris profunda, die auch als Ramus perforans I bezeichnet wird, gibt es zwischen den Aa. metatarsales plantares und dorsales Verbindungen, die Rr. perforantes II-IV, die bei schwach ausgeprägter A. plantaris profunda die Gefäßversorgung sicherstellen und entsprechend stärker ausgebildet sein können. Die A. fibularis kann über ihre kommunizierenden Äste, dem Ramus perforans zur A. dorsalis pedis oder dem Ramus communicans zur A. tibialis posterior, an der arteriellen Versorgung der Fußsohle beteiligt sein. Bei schwacher Ausbildung der A. tibialis posterior und/oder A. tibialis anterior kann diese durch die A. fibularis als phylogenetisch ältestes und damit konstantestes Gefäß der drei Unterschenkelarterien sogar teilweise oder vollständig ersetzt werden. Die „Ringanastomose“ hat für die Gefäßchirurgie eine große Bedeutung. Beim popliteodistalen Bypass orientiert sich die Wahl des distalen Anschlussgefäßes daran, über welches Gefäß sich der Arcus plantaris angiographisch füllt. Eine Kollateralbildung beim Erwachsenen infolge atherosklerotischer Veränderungen über ursprünglich embryologische Gegebenheiten ist denkbar. 2. Die makroskopische Präparation kleinster Gefäße am Fuß wird durch die Injektion der roten Injektionslösung Microfil® erleichtert. Zur fotografischen Dokumentation ist eine Farbmarkierung der Arterien von außen notwendig, um den Gefäßverlauf sichtbar zu machen. 3. Digitale Subtraktionsangiographie an Leichenmaterial ist nur an Thiel-fixiertem Material möglich, da diese Methode die Gewebeverhältnisse in ihrer natürlichen Konsistenz erhält. Das Einbinden der Schleusen und die Injektion von Kontrastmittel in das Gefäßsystem sind durchführbar, weil die Gefäßlumina durchgängig bleiben. Alkohol- oder Formaldehyd-fixiertes Material ist für diese Zwecke ungeeignet, da das Gewebe aushärtet und in den Gefäßen befindliche Blutreste koagulieren. Dadurch wird eine Kontrastmittel-Injektion unmöglich. 4. Dass histologische Färbungen an langzeitfixiertem Material möglich sind, konnte bestätigt werden. Nach Modifikation der Färbevorschriften erlauben sie die Bewertung des Atherosklerosegrades. Der schwerste Befall mit Grad 4 befindet sich in den Arterien der Kniekehle. Die Fußarterien sind mit Grad 2 geringer befallen. 5. Dauerpräparate verbleiben in der anatomischen Lehrsammlung bzw. im Fundus von Anschauungsmaterial. Sie werden zukünftig zur Demonstration anatomischer Strukturen im Rahmen klinischer Kurse und im Studentenunterricht verwendet. 6. Die Anatomie als Grundlagenfach der Medizin hat in der Lehre einen hohen Stellenwert und in allen Studienabschnitten eine hohe klinische Relevanz. Gemeinsame Lehrveranstaltungen von Anatomie und Klinik wecken bei Studenten großes Interesse und fördern die Motivation. Im Rahmen der ärztlichen Aus- und Weiterbildung werden in klinischen Kursen am Institut für Anatomie beispielsweise Untersuchungsmethoden und Operationsbedingungen simuliert. Kliniker wiederholen, festigen oder vertiefen ihre anatomischen Kenntnisse. Vor allem die chirurgischen Fächer profitieren von diesen praktischen Trainingsmöglichkeiten. Wie die Arbeit am Beispiel der Gefäßchirurgie zeigt, bedingt eine gute Zusammenarbeit zwischen Anatomie und Klinik eine sichere klinische Praxis und eine lebendige Anatomie mit klinischen Bezügen. / Summary Vascular diseases and diabetes mellitus show rising frequency in the Western world and are often accompanied by amputation. The amputation rate is still increasing despite major developments in diagnostics and therapy. Especially patients with diabetes mellitus are at high risk. Because of the special pattern with more severe atherosclerosis in the crural vessels than in the femoral and pedal arteries, the pedal bypass surgery provides excellent vessel patency and limb salvage rates in diabetic patients and can often prevent amputation. A solid knowledge about anatomical variations in the operating area is a precondition for bypass operations. This dissertation deals with variations of arteries from the lower leg and foot. Lower legs from alcohol-fixed and Thiel-fixed cadavers were examined with different methods: The alcohol-fixed legs (n=12) were dissected macroscopically for variations of the arteries and documented by photographes. Samples along the vessel course (n=32) were taken for histological evaluation of the atherosclerotic degrees. Two legs were plastinated with polyethylene glycol. The Thiel-fixed legs (n=10) were tested for digital subtraction angiography (DSA). The following questions had to be answered: 1. Which arterial variations can be found for the lower leg and foot? How do the vessels communicate between the sole and the dorsum of the foot? 2. How are small foot vessels dissected for photographical documentation? 3. Can Thiel-fixed material be used for DSA? 4. Do proximal and distal vessels show different degrees of atherosclerosis? 5. Which relevance does plastination have for the medical education? 6. How important is Gross anatomy for the clinicians? Results and conclusions: 1. The following variations occurred: trifurcation, anterior tibiofibular truncus with high branching from the posterior tibial artery and the anterior tibial artery originating from the fibular artery, dominant fibular artery, plantar arch running through the second interosseus space, dominant deep plantar artery, dominant deep branch of the medial plantar artery, prominent arcuate artery. The arteries for the plantar arch, supplying most of the foot arteries, show a high diversification. They are part of the “ring anastomosis” which assures a good blood supply via different vessels connecting the dorsum and the sole of the foot. Beside the deep plantar artery, also named as “perforating branch I”, there are other connecting branches between the plantar and dorsal metatarsal arteries - the perforating braches II, III and IV. These branches are highly developed in case of an undeveloped deep plantar artery. The fibular artery can be involved in the blood supply of the foot via a communicating branch to the posterior tibial artery and the perforating branch to the dorsalis pedis artery. The fibular artery, which is phylogenetically the oldest crural vessel, can be highly developed in case of inferior anterior tibial artery and/or posterior tibial artery. The “ring anastomosis” is very important for vascular surgery. The inflow and outflow vessels of a popliteodistal bypass are chosen after angiography of the plantar arch showing the vessel for the supply of the plantar arch. 2. Macroscopical dissection of very small foot vessels can be facilitated by injection of a special plastic, Microfil®-solution. The arteries have to be additionally coloured by help of special markers for photographical documentation. 3. DSA can just be done with Thiel-fixed material. Thiel-fixation allows DSA because maintained in situ conditions. The blood is not coagulated and the vessels stay patent for contrast medium. Alcohol-fixed or formaldehyde-fixed material is not suitable for DSA because of clotted blood in the vessels impeding injection of contrast agent. 4. It is confirmed that histological examination is possible with long fixed material. After modification of the staining protocol the sections could be used for evaluation of the atherosclerotic degree. The popliteal arteries are more affected with degree 4 in comparison to the foot arteries with degree 2. 5. Plastinates are displayed in the anatomical collection of the Institute for Anatomy. They will be used for anatomical demonstrations in the lessons of students and in clinical courses. 6. Anatomy as basic knowledge is very important for teaching medical students and has a high clinical relevance in every phase of the medical course. Interdisciplinary lessons between anatomy and clinical disciplines awake interest and motivate students. Advanced medical training is obtained at the Institute for Anatomy by simulating endoscopic examination and developing new surgical techniques. Clinicians repeat, stabilize and deepen their anatomical knowledge. Especially surgeons benefit from these training possibilities. Using the example of vascular bypass surgery the present dissertation shows the value of a good cooperation between anatomy and clinic to provide a safe clinical practice and a lively anatomy with clinical references.
138

Anatomische Voraussetzungen für pedale Bypass-Revaskularisationen

Wacker, Anne 08 December 2011 (has links)
Zusammenfassung Gefäßerkrankungen und Diabetes mellitus nehmen als Krankheiten der modernen Zivilisation zu. Sie gehen oft mit dem Risiko einer Amputation einher. Trotz verbesserter Therapie aufgrund des medizinischen Fortschritts steigen die Amputationsraten. Besonders gefährdet sind Patienten mit Diabetes mellitus. Aufgrund des besonderen Atherosklerosebefallsmusters mit Verschluss der kruralen Gefäße bei relativer Aussparung der Oberschenkel- und Fußarterien erzielen pedale Bypässe bei diabetischen Patienten besonders gute Ergebnisse im Hinblick auf die Wiederherstellung der Fußdurchblutung. Ein pedaler Bypass kann eine drohende Amputation oft verhindern. Voraussetzungen für eine pedale Bypass-Operation sind umfassende anatomische Kenntnisse über die Variabilität der Arterien im Operationsgebiet. Die vorliegende Arbeit befasst sich mit den Gefäßvariationen an Unterschenkel und Fuß. Mit unterschiedlichen Methoden wurden Alkohol-fixierte (n=12) und Thiel-fixierte (n=10) Beinpräparate auf arterielle Variabilität untersucht. Die Alkohol-fixierten Präparate wurden makroskopisch präpariert und fotografisch dokumentiert, außerdem erfolgte eine Probenentnahme zur histologischen Untersuchung der Atherosklerosegrade in verschiedenen Gefäßregionen (n=32) und die Herstellung von zwei Dauerpräparaten. An Thiel-fixiertem Material wurde die Digitale Subtraktionsangiographie (DSA) getestet. Folgende Fragestellungen waren zu beantworten: 1. Welche Variationen der Blutgefäße finden sich für den Unterschenkel und Fuß? Wie kommunizieren die Gefäße zwischen Fußsohle und Fußrücken? 2. Wie können kleinste Gefäße am Fuß präpariert und fotografisch dokumentiert werden? 3. Lässt sich an fixiertem Leichenmaterial eine Digitale Subtraktionsangiographie durchzuführen? 4. Zeigen proximale und distale Blutgefäße des Beines einen unterschiedlichen Befall der Atherosklerose? 5. Welche Bedeutung hat die Herstellung von Dauerpräparaten für den studentischen Unterricht? 6. Welche Bedeutung hat die makroskopische Anatomie für die Klinik? Die Ergebnisse und Schlussfolgerungen sind: 1. Während der makroskopischen Präparation fanden sich folgende Variationen: Trifurkation, Truncus tibiofibularis anterior mit hohem Abgang der A. tibialis posterior und Abgang der A. tibialis anterior aus der A. fibularis, eine sehr dominante A. fibularis bei schwach ausgeprägter A. tibialis posterior, ein Arcus plantaris durch den zweiten intermetatarsalen Spalt laufend, kräftig ausgebildete A. plantaris profunda, kräftiger tiefer Ast der A. plantaris medialis, stark ausgeprägte A. arcuata. Die den Arcus plantaris versorgenden Arterien, vor allem die A. plantaris lateralis und die A. plantaris profunda, variieren stark in ihrer Ausprägung. Sie sind Teil der „Ringanastomose”, die eine Durchblutung des Fußes über die Verbindungen verschiedener Gefäße zwischen Fußsohle und Fußrücken gewährleistet. Neben der A. plantaris profunda, die auch als Ramus perforans I bezeichnet wird, gibt es zwischen den Aa. metatarsales plantares und dorsales Verbindungen, die Rr. perforantes II-IV, die bei schwach ausgeprägter A. plantaris profunda die Gefäßversorgung sicherstellen und entsprechend stärker ausgebildet sein können. Die A. fibularis kann über ihre kommunizierenden Äste, dem Ramus perforans zur A. dorsalis pedis oder dem Ramus communicans zur A. tibialis posterior, an der arteriellen Versorgung der Fußsohle beteiligt sein. Bei schwacher Ausbildung der A. tibialis posterior und/oder A. tibialis anterior kann diese durch die A. fibularis als phylogenetisch ältestes und damit konstantestes Gefäß der drei Unterschenkelarterien sogar teilweise oder vollständig ersetzt werden. Die „Ringanastomose“ hat für die Gefäßchirurgie eine große Bedeutung. Beim popliteodistalen Bypass orientiert sich die Wahl des distalen Anschlussgefäßes daran, über welches Gefäß sich der Arcus plantaris angiographisch füllt. Eine Kollateralbildung beim Erwachsenen infolge atherosklerotischer Veränderungen über ursprünglich embryologische Gegebenheiten ist denkbar. 2. Die makroskopische Präparation kleinster Gefäße am Fuß wird durch die Injektion der roten Injektionslösung Microfil® erleichtert. Zur fotografischen Dokumentation ist eine Farbmarkierung der Arterien von außen notwendig, um den Gefäßverlauf sichtbar zu machen. 3. Digitale Subtraktionsangiographie an Leichenmaterial ist nur an Thiel-fixiertem Material möglich, da diese Methode die Gewebeverhältnisse in ihrer natürlichen Konsistenz erhält. Das Einbinden der Schleusen und die Injektion von Kontrastmittel in das Gefäßsystem sind durchführbar, weil die Gefäßlumina durchgängig bleiben. Alkohol- oder Formaldehyd-fixiertes Material ist für diese Zwecke ungeeignet, da das Gewebe aushärtet und in den Gefäßen befindliche Blutreste koagulieren. Dadurch wird eine Kontrastmittel-Injektion unmöglich. 4. Dass histologische Färbungen an langzeitfixiertem Material möglich sind, konnte bestätigt werden. Nach Modifikation der Färbevorschriften erlauben sie die Bewertung des Atherosklerosegrades. Der schwerste Befall mit Grad 4 befindet sich in den Arterien der Kniekehle. Die Fußarterien sind mit Grad 2 geringer befallen. 5. Dauerpräparate verbleiben in der anatomischen Lehrsammlung bzw. im Fundus von Anschauungsmaterial. Sie werden zukünftig zur Demonstration anatomischer Strukturen im Rahmen klinischer Kurse und im Studentenunterricht verwendet. 6. Die Anatomie als Grundlagenfach der Medizin hat in der Lehre einen hohen Stellenwert und in allen Studienabschnitten eine hohe klinische Relevanz. Gemeinsame Lehrveranstaltungen von Anatomie und Klinik wecken bei Studenten großes Interesse und fördern die Motivation. Im Rahmen der ärztlichen Aus- und Weiterbildung werden in klinischen Kursen am Institut für Anatomie beispielsweise Untersuchungsmethoden und Operationsbedingungen simuliert. Kliniker wiederholen, festigen oder vertiefen ihre anatomischen Kenntnisse. Vor allem die chirurgischen Fächer profitieren von diesen praktischen Trainingsmöglichkeiten. Wie die Arbeit am Beispiel der Gefäßchirurgie zeigt, bedingt eine gute Zusammenarbeit zwischen Anatomie und Klinik eine sichere klinische Praxis und eine lebendige Anatomie mit klinischen Bezügen. / Summary Vascular diseases and diabetes mellitus show rising frequency in the Western world and are often accompanied by amputation. The amputation rate is still increasing despite major developments in diagnostics and therapy. Especially patients with diabetes mellitus are at high risk. Because of the special pattern with more severe atherosclerosis in the crural vessels than in the femoral and pedal arteries, the pedal bypass surgery provides excellent vessel patency and limb salvage rates in diabetic patients and can often prevent amputation. A solid knowledge about anatomical variations in the operating area is a precondition for bypass operations. This dissertation deals with variations of arteries from the lower leg and foot. Lower legs from alcohol-fixed and Thiel-fixed cadavers were examined with different methods: The alcohol-fixed legs (n=12) were dissected macroscopically for variations of the arteries and documented by photographes. Samples along the vessel course (n=32) were taken for histological evaluation of the atherosclerotic degrees. Two legs were plastinated with polyethylene glycol. The Thiel-fixed legs (n=10) were tested for digital subtraction angiography (DSA). The following questions had to be answered: 1. Which arterial variations can be found for the lower leg and foot? How do the vessels communicate between the sole and the dorsum of the foot? 2. How are small foot vessels dissected for photographical documentation? 3. Can Thiel-fixed material be used for DSA? 4. Do proximal and distal vessels show different degrees of atherosclerosis? 5. Which relevance does plastination have for the medical education? 6. How important is Gross anatomy for the clinicians? Results and conclusions: 1. The following variations occurred: trifurcation, anterior tibiofibular truncus with high branching from the posterior tibial artery and the anterior tibial artery originating from the fibular artery, dominant fibular artery, plantar arch running through the second interosseus space, dominant deep plantar artery, dominant deep branch of the medial plantar artery, prominent arcuate artery. The arteries for the plantar arch, supplying most of the foot arteries, show a high diversification. They are part of the “ring anastomosis” which assures a good blood supply via different vessels connecting the dorsum and the sole of the foot. Beside the deep plantar artery, also named as “perforating branch I”, there are other connecting branches between the plantar and dorsal metatarsal arteries - the perforating braches II, III and IV. These branches are highly developed in case of an undeveloped deep plantar artery. The fibular artery can be involved in the blood supply of the foot via a communicating branch to the posterior tibial artery and the perforating branch to the dorsalis pedis artery. The fibular artery, which is phylogenetically the oldest crural vessel, can be highly developed in case of inferior anterior tibial artery and/or posterior tibial artery. The “ring anastomosis” is very important for vascular surgery. The inflow and outflow vessels of a popliteodistal bypass are chosen after angiography of the plantar arch showing the vessel for the supply of the plantar arch. 2. Macroscopical dissection of very small foot vessels can be facilitated by injection of a special plastic, Microfil®-solution. The arteries have to be additionally coloured by help of special markers for photographical documentation. 3. DSA can just be done with Thiel-fixed material. Thiel-fixation allows DSA because maintained in situ conditions. The blood is not coagulated and the vessels stay patent for contrast medium. Alcohol-fixed or formaldehyde-fixed material is not suitable for DSA because of clotted blood in the vessels impeding injection of contrast agent. 4. It is confirmed that histological examination is possible with long fixed material. After modification of the staining protocol the sections could be used for evaluation of the atherosclerotic degree. The popliteal arteries are more affected with degree 4 in comparison to the foot arteries with degree 2. 5. Plastinates are displayed in the anatomical collection of the Institute for Anatomy. They will be used for anatomical demonstrations in the lessons of students and in clinical courses. 6. Anatomy as basic knowledge is very important for teaching medical students and has a high clinical relevance in every phase of the medical course. Interdisciplinary lessons between anatomy and clinical disciplines awake interest and motivate students. Advanced medical training is obtained at the Institute for Anatomy by simulating endoscopic examination and developing new surgical techniques. Clinicians repeat, stabilize and deepen their anatomical knowledge. Especially surgeons benefit from these training possibilities. Using the example of vascular bypass surgery the present dissertation shows the value of a good cooperation between anatomy and clinic to provide a safe clinical practice and a lively anatomy with clinical references.
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Correlation between cerebral tissue oxygen saturation and central venous oxygen saturation during off-pump coronary artery bypass graft surgery

Harilall, Yakeen January 2009 (has links)
Submitted in partial fulfilment of the requirements for the Degree of Masters in Technology: Clinical Technology, Durban University of Technology, 2009. / Currently, off-pump coronary artery bypass surgery (OPCAB) is a selectively employed technique for myocardial revascularization used in the majority of heart units worldwide. This strategy obviates the documented deleterious effects of cardiopulmonary bypass. However the occurrence of neurological sequelae associated with OPCAB ranges from minor cognitive dysfunction to major stroke. Haemodynamic instability throughout the positioning, stabilization and interruption of coronary blood flow are regarded as important factors that affect the performance of off-pump surgery. Fluctuations during the perioperative period, in particular manipulation of the heart could result in temporary brain hypoperfusion and neurological sequelae. To predict those patients that are predisposed to cerebral complications, investigators have used neurological monitoring, in particular Near-infra red spectroscopy (NIRS) during cardiac surgery. Aims and Objectives of the study This prospective, observational study was carried out to assess the correlation between cerebral oxygen saturation and central venous saturation during OPCAB surgery. Central venous saturation is an important variable used to assess global tissue perfusion and could therefore be advocated as a surrogate measure of cerebral oxygen saturation. In addition variables such as mean arterial (MAP) pressure, heart rate (HR), patient oxygen saturation (SpO2), partial pressure of carbon dioxide (PcvCO2), haematocrit (Hct) and lactate were also measured to determine if they were independent predictors of cerebral desaturation. This study is one of the first done in the South African population group. iv Methodology Twenty patients undergoing OPCAB surgery from the Cardiothoracic unit at Inkosi Albert Luthuli Central Hospital, Durban, South Africa were recruited in the trial. Cerebral somasensors were placed on the patients forehead to measure left and right cerebral saturations. These sensors were linked by cables to the cerebral monitor (NIRS), INVOS model 5100C. Eight time periods throughout the surgical procedure whereby patients would be haemodynamically unstable were identified. These time periods included, post induction and pre sternotomy, pre and post placement of swabs beneath the heart, pre and post placement of the stabilizer device (Octopus), pre and post snaring of the LAD (left anterior branch of the coronary arteries), pre anastomosis and during anastomosis of the coronary arteries, second sample during anastomosis and post anastomosis, pre and post removal of swabs from beneath the heart, pre and post transfer of the patient to the ICU bed. These time periods constituted the sampling period pre and post manoeuvres. Eight paired measurements, i.e., MAP, PaCO2, HR, Hct, lactate, SpO2, central venous saturation (ScvO2) and cerebral oxygen saturation (rSo2) per patient were taken during these time periods. Recording of cerebral saturations and blood samples from the central venous line were taken during these eight time periods in order to determine the correlation between central venous and cerebral oxygen saturations. Results Strong positive correlations between central venous saturation and cerebral saturation presented in majority of the sampling time periods throughout the study (post induction and pre sternotomy, post placement of swabs beneath the heart, post snaring of the LAD (left anterior branch of the coronary arteries, pre anastomosis and during anastomosis of the coronary arteries, second sample during v anastomosis, pre and post transfer of the patient to the ICU bed). The positive correlation indicates that central venous saturation can be used as a surrogate measure of cerebral oxygen saturation during OPCAB surgery. Conclusion The absence or poor correlation of MAP, HR, PcvCO2, heamatocrit, lactate, and patient saturation to cerebral saturation in this study suggests that insertion of a central venous line (CVP) during OPCAB should be a fundamental clinical requirement.
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The effect of optimizing cerebral tissue oxygen saturation on markers of neurological injury during coronary artery bypass graft surgery

Harilall, Yakeen January 2011 (has links)
Submitted in partial fulfilment of the requirements for the Degree of Doctor of Technology: Clinical technology, Durban University of Technology, 2011. / Surgical revascularization of the coronary arteries is a cornerstone of cardiothoracic surgery. The enduring nature of coronary artery bypass grafting (CABG) bespeaks of its history and proven efficacy. However, cerebral deoxygenation during on-pump coronary artery bypass graft surgery may be associated with adverse neurological sequelae. Advanced age and the incidence of preoperative co-morbidity in patients presenting for coronary artery bypass graft surgery increases the potential for stroke and other adverse perioperative outcomes (Murkin, Adams, Quantz, Bainbridge and Novick, 2007). It is hypothesized, that by using the brain as an index organ, interventions to improve cerebral oxygenation would have systemic benefits for cardiac surgical patients. In an attempt to predict those patients that are predisposed to cerebral complications, investigators have used neurological monitoring ie, Near infrared spectroscopy (NIRS) to enhance detection of hypoxic conditions associated with neurological injury (Hoffman, 2006). Serum S100B protein has been used as a biochemical marker of brain injury during cardiac surgery. Elevated levels serve as a potential marker of brain cell damage and adverse neurological outcomes (Einav, Itshayek, Kark, Ovadia, Weiniger and Shoshan, 2008). Aims and Objectives of the study This prospective, quantitative, interventional study was carried out to maintain cerebral tissue oxygen saturation during cardiopulmonary bypass above 75% of the baseline level by implementation of a proposed interventional protocol. The analysis of S100B which is a marker of neurological injury and optimization of regional cerebral oxygen saturation would allow for the formulation of an algorithm which could be implemented during on-pump coronary artery bypass graft surgery as a preventive clinical measure further reducing the risk of neurological injury. Central venous lines (CVP) are inserted routinely during cardiac surgery. Central venous oxygen saturation is a global marker of tissue oxygenation. A secondary aim of the study was to determine if a correlation existed between central venous and cerebral tissue oxygen saturations. If a positive correlation existed then central venous oxygen saturation could be used as a surrogate measure of cerebral tissue oxygen saturation during on-pump coronary artery bypass graft surgery. This study is one of the first done in the South African population group. Methods Forty (40) patients undergoing on-pump coronary artery bypass graft surgery were recruited at Inkosi Albert Luthuli Central Hospital. Patients were randomized into a control group (n=20) and interventional group (n=20) using a sealed envelope system. The envelope contained designation to either group. Envelopes were randomly chosen. Intraoperative regional cerebral oxygen saturation (rSO2 ) monitoring with active display and treatment intervention protocol was administered for the interventional group. In the control group regional cerebral oxygen saturation monitoring was not visible to the perfusionist operating the heart lung machine during cardiopulmonary bypass (blinded). Recording of regional cerebral saturation was conducted by an independent person (another perfusionist) who was not involved in the management of the case so as to ensure that no interventions were carried out on the control group. Arterial blood samples for the measurement of serum S100B were taken pre and postoperatively. An enzyme immunoassay (ELISA) was used for the quantitative and comparative measurement of human S100B concentrations for both groups. Central venous oxygen saturation was monitored from the CVP using the Edwards Vigileo monitor. Cerebral monitoring constituted the use of Near infrared spectroscopy monitoring using the Invos 5100c, Somonetics Corp, Troy MI monitor. Adhesive optode pads were be placed over each fronto- temporal area for cerebral oxygen measurement. During cardiopulmonary bypass, eight time period measurements of mean arterial pressure (MAP), heart rate, temperature, activated clotting time (ACT), patient oxygen saturation (SpO2), partial pressure of carbon dioxide (pCO2), haematocrit, lactate, pH, haemoglobin (Hb), base excess (BE), potassium (K+), sodium (Na+), glucose, calcium (Ca2+), central venous oxygen saturation (ScvO2), cerebral tissue oxygen saturation (rSO2), fraction inspired oxygen (FiO2 ), sweep rate, pump flow rate (cardiac index), and percentage isoflurane per patient were taken. The time periods when data was recorded included: 5 minutes after onset of cardiopulmonary bypass, aortic cross clamping, after cardioplegic arrest, during distal anastomosis, during proximal anastomosis, during rewarming, after aortic cross clamp release and before termination of cardiopulmonary bypass. Baseline measurements were also taken. Clinical data recorded for both groups included: the number of grafts performed, cardiopulmonary bypass time, cross clamp time, red blood cells administered (packed cells), amount of adrenalin infused and total cerebral desaturation time. A prioritized intraoperative management protocol to maintain rSO2 values above 75% of the baseline threshold during cardiopulmonary bypass was followed. Cerebral desaturation was defined as a decrease in saturation values below 70% of baseline for more than one minute. Interventions commenced within 15 seconds of decrease below 75% of baseline value. Results The results of the study show that there was a highly significant difference in the change in S100B concentrations pre and post surgery between the interventional and control groups. The intervention vii group showed a smaller increase in S100B concentration of 37.3 picograms per millilitre (pg/ml) while the control group showed a larger increase of 139.3 pg/ml. Therefore, the control group showed a significantly higher increase in S100B concentration over time than the intervention group (p < 0.001). Maximizing pump flow rates was the most common intervention used (45 times) followed by maintaining partial pressure of carbon dioxide to approximately 40 mmHg (28 times), increasing mean arterial pressure by administration of adrenalin (11 times) and administration of red blood cells to increase haematocrit (11 times). There was a highly statistically significant treatment effect within the intervention group for each of the above interventions compared with no intervention. The above mentioned interventions significantly affected right and left cerebral oxygen saturations. However, administration of red blood cells was not found to significantly increase right (p = 0.165) and left (p = 0.169) cerebral oxygen saturation within the intervention group. The study highlighted a significant difference between the intervention and control groups in terms of cerebral desaturation time (p <0.001). The mean desaturation time for the control group was 63.85 minutes as compared to 24.7 minutes in the interventional group. Cerebral desaturation occurred predominantly during aortic cross clamping, distal anastomosis of coronary arteries and aortic cross clamp release. Predictors of cerebral oxygen desaturation included, partial pressure of carbon dioxide (pCO2), temperature, pump flow rate (LMP), mean arterial pressure (MAP), haematocrit, heart rate (HR) and patient oxygen saturation (SpO2). Central venous oxygen saturation was not significantly related to right (p = 0.244) or left (p = 0.613) cerebral oxygen saturations. Therefore central venous oxygen saturation cannot be used as a surrogate measure of cerebral tissue oxygen saturation during on-pump coronary artery bypass graft surgery. viii Conclusion These findings demonstrate the positive effect of optimizing cerebral oxygen saturation using an interventional protocol on markers of neurological injury (S100B). Optimization of pump flow rate, partial pressure of carbon dioxide and mean arterial pressure would result in increased cerebral oxygen saturation levels and a reduction in neurological injury. Therefore, an algorithm incorporating these interventions can be formulated. Monitoring specifically for brain oxygen saturation together with an effective treatment protocol to deal with cerebral desaturation during on-pump CABG must be advocated.

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