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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.
41

Efeitos do sevoflurano administrado como pré-condicionante ou de modo contínuo nas lesões locais e sistêmicas da isquemia/reperfusão hepática. / Effects of sevoflurane preconditioning or continuously in local and systemic lesions of hepatic ischemia/reperfusion injury in the rat

Fernanda Paula Cavalcante 28 January 2014 (has links)
INTRODUÇÃO: Lesões de isquemia/reperfusão hepáticas significativas podem ocorrer durante hepatectomias, no transplante hepático e no trauma hepático. A isquemia/reperfusão hepática pode levar à resposta inflamatória sistêmica associada a lesões locais e a distância. Estudos já demonstraram o efeito protetor do sevoflurano sobre as lesões de isquemia/reperfusão hepáticas; entretanto, nenhuma pesquisa, até o momento, estudou se esta proteção se dá por pré-condicionamento ou se depende da administração contínua do anestésico durante todo o período de isquemia/reperfusão. OBJETIVO: O objetivo deste estudo é avaliar o efeito do précondicionamento com sevoflurano ou da sua administração contínua nas lesões locais e sistêmicas da isquemia/reperfusão hepática em ratos. MÉTODOS: Os animais foram divididos em quatro grupos: grupo SHAM (n=12): animais submetidos à laparotomia mediana sem isquemia hepática; grupo Sem Tratamento (n=13): animais submetidos à isquemia/reperfusão hepática sem administração de sevoflurano; grupo Pré-condicionamento (n=13): sevoflurano foi administrado por 30 minutos e descontinuado antes da isquemia hepática; grupo Sevoflurano Contínuo (n=13): sevoflurano foi administrado por 30 minutos antes da isquemia hepática e também durante todo o período de isquemia/reperfusão. Nos três últimos grupos, ratos machos da linhagem wistar foram submetidos a modelo de isquemia hepática parcial por meio do clampeamento do pedículo hepático comum dos lobos mediano e anterolateral esquerdo. O clampe foi removido após 1 hora de isquemia e as análises realizadas após 4 horas de reperfusão. Em todos os grupos, a indução anestésica foi realizada com cetamina e xilazina, e os ratos foram intubados e submetidos à ventilação mecânica. O sangue foi coletado para dosagens de AST, ALT, TNF-alfa, IL-6 e IL-10. Os lobos hepáticos isquêmicos e não isquêmicos foram separados para estudo das funções oxidativas e fosforilativas mitocondriais, conteúdo de malondialdeído e análise histológica. Também foram avaliadas permeabilidade vascular pulmonar atividade da mieloperoxidase pulmonar. RESULTADOS: Após 4 horas de reperfusão, o grupo Sevoflurano Contínuo apresentou elevação dos níveis séricos de AST e ALT significativamente menor que os grupos Pré-condicionamento e Sem Tratamento (p < 0,05). No grupo Sevoflurano Contínuo, houve redução significativa da disfunção mitocondrial e incidência de necrose nos lobos hepáticos isquêmicos comparado aos grupos Pré-condicionamento e Sem Tratamento (p < 0,05). A permeabilidade vascular pulmonar foi menor no grupo Sevoflurano Contínuo comparado aos grupos Pré-condicionamento e Sem Tratamento (p < 0,05). Não foram encontradas diferenças no conteúdo de malondialdeído no tecido hepático, na atividade da mieloperoxidase pulmonar e nos níveis séricos de TNF-alfa, IL-6 e IL-10 entre os grupos. CONCLUSÃO: O pré-condicionamento com o sevoflurano não demonstrou proteção contra as lesões locais e sistêmicas da isquemia/reperfusão hepática. Entretanto, a administração contínua de sevoflurano reduziu ambas as lesões locais, no fígado isquêmico, e a distância, nos pulmões, associadas à isquemia/reperfusão hepática pulmonar foi menor no grupo Sevoflurano Contínuo comparado aos grupos Pré-condicionamento e Sem Tratamento (p < 0,05). Não foram encontradas diferenças no conteúdo de malondialdeído no tecido hepático, na atividade da mieloperoxidase pulmonar e nos níveis séricos de TNF-alfa, IL-6 e IL-10 entre os grupos. CONCLUSÃO: O pré-condicionamento com sevoflurano não demonstrou proteção contra as lesões locais e sistêmicas da isquemia/reperfusão hepática. Entretanto, a administração contínua de sevoflurano reduziu ambas as lesões locais, no fígado isquêmico, e a distância, nos pulmões, associadas à isquemia/reperfusão hepática / INTRODUCTION: Significant liver ischemia/reperfusion injury can occur during hepatectomies, liver transplantation, and liver trauma. Hepatic ischemia/reperfusion can trigger a systemic inflammatory syndrome associated with both local and systemic lesions. Previous studies have shown that sevoflurane protects from liver ischemia/reperfusion injury; however it was not studied yet if this protection is mediated by preconditioning or if it depends on continuous use of the anesthetic during the whole I/R injury period. AIM: It was hypothesized that sevoflurane preconditioning or continuously would protect from local and systemic lesions of liver ischemia/reperfusion injury in the rat. METHODS: Rats were divided into 4 groups: SHAM Group (n=12): animals were submitted to median laparotomy without liver ischemia; No Treatment Group (n=13): animals were submitted to I/R injury and no sevoflurane was used; Preconditioning Group (n=13): sevoflurane was used during 30 minutes and discontinued before liver ischemia; and Continuous Sevoflurane Group (n=13): sevoflurane was used 30 minutes before liver ischemia and during the whole liver I/R injury time. In the last three groups, wistar male rats underwent partial liver ischemia performed by clamping the hepatic pedicle from medium and left anterior lateral lobules. Clamp was removed after 1 hour of partial ischemia and analysis were performed after 4 hours of reperfusion. In all groups, anesthesia was induced with cetamine and xylazine and rats were intubated and mechanical ventilated. Blood was collected for determinations of AST, ALT, TNF-alfa, IL-6, and IL-10. Ischemic and non-ischemic liver tissues were assembled for mitochondrial oxidation and phosphorylation, malondialdehyde content, and histological analysis. Pulmonary vascular permeability and myeloperoxidase activity were also determined. RESULTS: Four hours after reperfusion Continuous Sevoflurane group had shown elevation of serum AST and ALT levels significantly lower than Preconditioning and No Treatment groups (p < 0.05). A significant reduction on liver mitochondrial dysfunction and liver necrosis incidence were observed in ischemic liver tissues in Continuous Sevoflurane group compared to Preconditioning and No Treatment groups (p < 0.05). A reduction on pulmonary vascular permeability was observed in Continuous Sevoflurane group compared to Preconditioning and No Treatment groups (p < 0.05). No differences in liver malondialdehyde content, pulmonary myeloperoxidase activity, and serum TNF-alfa, IL-6, and IL-10 levels were observed among these groups. CONCLUSIONS: Sevoflurane preconditioning did not show protection against local and systemic lesions associated with liver ischemia/reperfusion injury. On the other hand, continuous sevoflurane administration reduced both local lesions, in ischemic liver, and systemic lesions, in the lungs, associated with liver ischemia/reperfusion injury
42

Påverkar val av anestesimedel den dagkirurgiska patientens postoperativa återhämtning? : En jämförelse mellan Propofol och Sevofluran

Blåder, Karin, Sunneskär, Karl January 2021 (has links)
Intravenös anestesi med Propofol eller inhalationsanestesi med gasen Sevofluran är de två vanligaste anestesiformerna i Sverige. Syftet med studien vara att undersöka om patienters postoperativa återhämtning skiljer sig åt beroende på om de sövts med Propofol eller Sevofluran. Datainsamlingen till studien genomfördes med systematisk litteraturöversikt baserad på integrativ metod. Både kvalitativa och kvantitativa studier samlades in, men enbart kvantitativa artiklar inkluderades. Resultatet visade att det under den postoperativa återhämtningen var vanligt förekommande med två postoperativa komplikationer, smärta samt illamående och kräkningar. Resultatet visar inga statistiskt signifikanta skillnader när det gällde dessa beroende på val av anestesimedel. Men vidare studier behövs inom ämnet, framför allt om kön eller ålder kan vara ytterligare påverkande faktorer. / Intravenous anesthesia with Propofol or inhalation anesthesia with the gas Sevoflurane are the two most common forms of anesthesia in Sweden. The purpose of the study was to investigate whether patient's postoperative recovery differs depending on whether they have been anesthetized with Propofol or Sevoflurane. The data collection for the study was carried out with a systematic literature review based on integrative research Both qualitative and quantitative studies were collected, but only quantitative articles were included. The results showed that during postoperative recovery it was common with two postoperative complications, pain, nausea, and vomiting. The results show no statistically significant differences in these depending on the choice of anesthetic agents. However, further studies are needed in the subject, especially if gender or age can be additional influencers.
43

The brain's electrical activity in deep anaesthesia:with special reference to EEG burst-suppression

Sonkajärvi, E. (Eila) 03 November 2015 (has links)
Abstract Several anaesthetics are able to induce a burst-suppression (B-S) pattern in the electroencephalogram (EEG) during deep levels of anaesthesia. A burst-suppression pattern consists of alternating high amplitude bursts and periods of suppressed background activity. All monitors measuring the adequacy of anaesthesia recognize the EEG B-S as one criterion. A better understanding of EEG burst-suppression is important in understanding the mechanisms of anaesthesia. The aim of the study was to acquire a more comprehensive understanding of the function of neural pathways during deep anaesthesia. The thesis is comprised of four prospective clinical studies with EEG recordings from 64 patients, and of one experimental study of a porcine model of epilepsy with EEG registrations together with BOLD fMRI during isoflurane anaesthesia (II). In study I, somatosensory cortical evoked responses to median nerve stimulation were studied under sevoflurane anaesthesia at EEG B-S levels. In study III, The EEGs of three Parkinson`s patients were observed to describe the characteristics of B-S during propofol anaesthesia using scalp electrodes and depth electrodes in the subthalamic nucleus. In study IV, EEG topography was observed in 20 healthy children under anaesthesia mask induction with sevoflurane. Twenty male patients were randomized to either controlled hyperventilation or spontaneous breathing groups for anaesthesia mask induction with sevoflurane in study V. EEG alterations in relation to haemodynamic responses were examined in studies IV and V. Somatosensory information reached the cortex even during deep anaesthesia at EEG burst-suppression level. Further processing of these impulses in the cortex was suppressed. The EEG slow wave oscillations were synchronous over the entire cerebral cortex, while spindles and sharp waves were produced by the sensorimotor cortex. The development of focal epileptic activity could be detected as a BOLD signal increase, which preceded the EEG spike activity. The epileptogenic property of sevoflurane used at high concentrations especially during hyperventilation but also during spontaneous breathing together with heart rate increase, was confirmed in healthy children and male. Spike- and polyspike waveforms concentrated in a multifocal manner frontocentrally. / Tiivistelmä Useat anestesia-aineet pystyvät aiheuttamaan aivosähkökäyrän (EEG) purskevaimentuman syvän anestesian aikana. Purskevaimentuma koostuu EEG:n suuriamplitudisten purskeiden sekä vaimentuneen taustatoiminnan vaihtelusta. Kaikkien anestesian syvyyttä mittaavien valvontalaitteiden toiminta perustuu osaltaan EEG:n purskevaimentuman tunnistamiseen. Tämän ilmiön parempi tunteminen on tärkeää anestesiamekanismien ymmärtämiseksi. Tutkimuksen päämääränä oli saada kattavampi käsitys hermoratojen toiminnasta syvässä anestesiassa. Väitöskirjatyö koostuu neljästä prospektiivisesta yhteensä 64 potilaan EEG-rekisteröinnit sisältävästä tutkimuksesta sekä yhdestä kokeellisen epilepsiatutkimuksen koe-eläintyöstä, jossa porsailla käytettiin isofluraanianestesiassa sekä EEG-rekisteröintejä sekä että magneettikuvantamista (fMRI) samanaikaisesti (II). Ensimmäisessä osatyössä tutkittiin keskihermon stimulaation aiheuttamia somatosensorisia herätepotentiaaleja aivokuorella EEG:n purskevaimentumatasolla sevofluraanianestesian aikana. Kolmannessa osatyössä selvitettiin propofolianestesian aiheuttamaa EEG:n purskevaimentumaa kolmelta Parkinsonin tautia sairastavalta potilaalta käyttäen sekä pintaelektrodien että subtalamisen aivotumakkeen syväelektrodien rekisteröintejä. Neljännessä osatyössä tutkittiin EEG:n topografiaa 20:llä terveeellä lapsella indusoimalla anestesia sevofluraanilla. Kaksikymmentä miespotilasta nukutettiin sevofluraanilla ja heidät satunnaistettiin joko kontrolloidun hyperventilaation tai spontaanin hengityksen ryhmiin osatyössä V. EEG-muutoksia sekä niiden yhteyttä verenkiertovasteisiin selviteltiin molemmissa osatöissä IV ja V. Omasta kehosta tuleviin tuntoärsykkeisiin liittyvä somatosensorinen informaatio saavutti aivokuoren myös syvässä EEG:n purskevaimentumatasoisessa anestesiassa. Impulssien jatkokäsittely aivokuorella oli kuitenkin estynyt. EEG:n hidasaaltotoiminta oli synkronista koko aivokuoren alueella, sen sijaan unisukkulat ja terävät aallot paikantuivat sensorimotoriselle aivokuorelle. Paikallisen epileptisen toiminnan kehittyminen oli mahdollista havaita jo ennen piikikkäiden EEG:n aaltomuotojen ilmaantumista edeltävänä BOLD-ilmiöön liittyvänä aivoverenkierron lisääntymisenä. Sevofluraanin epileptogeenisyys varmistui erityisesti hyperventilaation, mutta myös spontaanin hengityksen yhteydessä ja näihin liittyi sykkeen nousu sekä terveillä lapsilla että miehillä. Piikkejä ja monipiikkejä käsittävien aaltomuotojen keskittymistä esiintyi otsalohkon keskialueilla.
44

Green Anesthesia : Use of Inhalational Anesthetics and their Effect on our Climate / Miljövänlig Anestesi : Användning av inhalationsanestetika och dess påverkan på vårt klimat

Karchut, Sabina, Wedahl, Skylar January 2023 (has links)
This thesis has, commissioned by Dräger, an international company at the forefront of medical and safety technology, examined how the use of inhalational anesthetics affects the climate and environment. The purpose of this work is to examine how the Swedish healthcare sector currently works with inhalational anesthetics, how different anesthetic machines affect the emissions, as well as alternatives available to reduce anesthetic gases emissions. Climate change is a current issue in today’s society, but the impact of anesthetic gases on the climate is not widely known, despite their everyday use in the healthcare sector. Through data collection from two Swedish hospitals; Linköping University Hospital and Örebro University Hospital, an interview with medical and medical engineering staff, as well as a literature study the main question of the thesis could be answered; How do the most common anesthetic gases affect the environment? The results are presented in the form of diagrams showing the amount of anesthetic gas used in the aforementioned hospitals during surgeries. The results have been analyzed and discussed based on the research questions, and the different results from each hospital have been compared to each other. It can be seen that Dräger’s anesthesia machines have a relatively low consumption of sevoflurane, but it is impossible to draw any definitive conclusions due to lack of data, and lack of access to machines from other manufacturers. / Detta examensarbete har, på uppdrag av Dräger, ett internationellt företag i framkant inom medicin- och säkerhetsteknik, undersökt hur användning av inhalationsanestetika påverkar miljön. Målet med arbetet är att undersöka hur den svenska sjukvården för närvarande arbetar med inhalationsanestetika, hur olika anestesimaskiner påverkar utsläppen, samt alternativ som finns tillgängliga för att minska dessa utsläpp. Klimatförändringar är en aktuell fråga i dagens samhälle men påverkan av anestesigaser på klimatet är inte allmänt känt, trots att dessa används dagligen i hälsovården. Genom datainsamling från två svenska sjukhus; Linköpings Universitetssjukhus och Örebro Universitetssjukhus, intervjuer med medicinsk- och medicinteknisk personal, samt en litteraturstudie har arbetets problemställning besvarats; Hur påverkar de mest frekvent använda anestesigaserna miljön? Resultaten visar i diagramform hur mycket anestesi gas som använts i tidigare nämnda sjukhus under operationer. Resultaten har analyserats och diskuterats utifrån forskningsfrågorna, dessutom har de olika resultaten från respektive sjukhus jämförts med varandra. Det kan ses att Drägers anestesimaskiner har en relativt låg konsumtion av sevofluran, men brist på data samt brist på tillgång till maskiner från andra producenter gör det omöjligt att dra en konkret slutsats.

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