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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.
31

Short-Acting β-Adrenergic Antagonist Esmolol Given at Reperfusion Improves Survival After Prolonged Ventricular Fibrillation

Killingsworth, Cheryl R., Wei, Chih Chang, Dell'Italia, Louis J., Ardell, Jeffrey L., Kingsley, Melody A., Smith, William M., Ideker, Raymond E., Walcott, Gregory P. 25 May 2004 (has links)
Background-High catecholamine concentrations are cytotoxic to cardiac myocytes. We hypothesized that myocardial interstitial catecholamine levels are greatly elevated immediately after long-duration ventricular fibrillation (VF), defibrillation, and reperfusion and that the short-acting β-antagonist esmolol administered at reperfusion would protect against this catecholamine surge and improve survival. Methods and Results-In part 1 of this study, catecholamines from myocardial interstitial fluid (ISF) and aortic and coronary sinus plasma were quantified by use of 3H-labeled radioenzymatic assay in 8 open-chest, anesthetized pigs. Eight minutes of electrically induced VF was followed by internal defibrillation and reperfusion. By 4 minutes of VF, ISF norepinephrine increased significantly, from 1.3±0.3 to 7.4±2.4 ng/mL. Epinephrine increased significantly, from 0.4±0.2 to 1.5±0.7 ng/mL. ISF norepinephrine and epinephrine peaked at 219.2±92.1 and 63.7±25.1 ng/mL after defibrillation and reperfusion and decreased significantly to 12.2±3.5 and 6.7±3.1 ng/mL 23 minutes after defibrillation. Transcardiac catecholamine changes were similar. In part 2, 8 minutes of VF was followed by external defibrillation in anesthetized, closed-chest pigs. Animals received 1.0 mg/kg esmolol (n=8) or saline (n=8) intravenously at the start of cardiopulmonary resuscitation (CPR). Advanced cardiac life support, including CPR and epinephrine, was delivered to both groups. Esmolol before reperfusion improved return of spontaneous circulation and 4-hour survival (7/8 versus 3/8 survivors, χ2 P<0.05). Conclusions-Transcardiac and ISF norepinephrine and epinephrine levels are briefly massively elevated after 8 minutes of VF, defibrillation, and reperfusion. A short-acting β-antagonist administered immediately after defibrillation improves return of spontaneous circulation and 4-hour survival after this prolonged VF.
32

The Impact of Cardiopulmonary Baroreceptors on Pain Perception in Individuals at Differing Risk for Hypertension

Matson, Erin L. Hockman 16 April 2010 (has links)
No description available.
33

Extracorporeal Circulation: Effect of Long-Term (24-Hour) Circulation on Blood Components

Solberg, Robert Glen 20 May 2010 (has links)
Extracorporeal circulation damages blood and causes harmful side effects such as stroke and/or systemic inflammatory response in patients. Reactions of blood components to extracorporeal circulation include complement and inflammatory reactions, coagulation and thrombogenesis, frank hemolysis, and platelet activation and adhesion to the extracorporeal circuit. Non-physiologic pressure and flow produced by blood pumps contribute to blood injury. Two pump types, roller and centrifugal, are used for maintaining flow, with various models available from different manufacturers. This study compared the effects of these two pumps in identical, isolated, artificial circuits to a non-pumped control for a period of 24 hours on heparinized porcine blood. Hematology parameters were used to evaluate blood damage. Mean corpuscular volume, mean corpuscular hemoglobin, white blood cell count, platelet count, and mean platelet volume were affected by time of circulation. Mean corpuscular hemoglobin, platelet count, and red cell distribution width were different between circulated and non-circulated blood, however no differences were found between the pumping systems in any parameter. Red blood cell count, total hemoglobin, and hematocrit were not affected by time or treatment. The changes observed in this study have implications for the use of extracorporeal circulation in the clinical setting and in future use of blood as a potential organ perfusion medium. / Master of Science
34

Interactions between Carotid and Cardiopulmonary Baroreceptor Populations during Dynamic Exercise in Man

Potts, Jeffrey Thomas 05 1900 (has links)
During dynamic exercise the arterial baroreflexes have been thought to reset to the prevailing level of systemic pressure in order to modulate transient changes in blood pressure with the same sensitivity (gain) as at rest. To test this hypothesis, cardiovascular responses to dynamic exercise and carotid baroreflex responses to graded neck suction and neck pressure (NS/NP) were examined in seven men of moderate fitness (V02 = 41.4±3.6 ml O2*kg^-1*min^-1) during two levels (20% and 40% of peak oxygen uptake) of steady-state exercise. In addition, deactivation of cardiopulmonary baroreceptors has been thought to increase carotid baroreflex responsiveness in the quiescent state in man.
35

Predictors of cardiopulmonary arrest outcome in a comprehensive cancer center intensive care unit

Khasawneh, Faisal, Kamel, Mahmoud, Abu-Zaid, Mohammad January 2013 (has links)
BACKGROUND:Some comprehensive cancer centers in industrialized countries have reported improved outcomes in their cardiopulmonary arrest (CPA) patients. Little is known about the outcomes and predictors of CPA in cancer centers in other parts of the world. The objective of this study was to examine the predictors of CPA outcome in a comprehensive cancer center closed medical-surgical intensive care unit (ICU) located in Amman, Jordan.METHODS:In this retrospective single-center cohort study, we identified 104 patients who had a CPA during their stay in the ICU between 1/1/2008 and 6/30/2009. Demographic data and CPA-related variables and outcome were extracted from medical records. Comparisons between different variables and CPA outcome were conducted using logistic regression.RESULTS:The mean age of the group was 49.7+/-15.3years. The mean APACHE II score was 23.7+/-8.0. Thirty six patients (34.6%) were resuscitated successfully but 8 of them (7.7% of the cohort) left the ICU alive and only 6 out of the 8 (5.8% of the cohort) left the hospital alive. The following variables predict resuscitation failure: acute kidney injury (OR 1.7, CI: 1.1 - 2.6), being on mechanical ventilation (OR 3.8, CI: 1.3 - 11), refractory shock (OR 4.7, CI: 1.8 - 12) and CPR duration (OR 1.1, CI: 1.1 - 1.2).CONCLUSION:Survival among cancer patients who develop CPA in the ICU continues to be poor. Once cancer patients suffered a CPA in the ICU multiple factors predicted resuscitation failure but CPR duration was the only factor that predicted resuscitation failure and ICU as well as hospital mortality.
36

Exposure to particulate matter and the related health impacts in major Estonian cities

Orru, Hans January 2009 (has links)
Particulate matter (PM) is one of the most studied and problematic pollutants due to its toxicity and relati­vely high concentrations. This thesis aims to clarify the main sources and exposures of PM in Tallinn and Tartu, study the associations with health effects, and estimate the extent of those effects with health impact assessment (HIA). It appeared that the main sources of particulate air pollution in Tallinn (the capital of Estonia) and Tartu (the second largest city of Estonia) are local heating and traffic, inclu­ding road dust. In addition to local emissions, particulate levels are affected by transboundary pollution. If the transboundary air masses originated from the Eastern European areas, the concentration as well as the oxidative capacity of fine particles was significantly higher in urban background air in Tartu compared to air masses coming from Scandinavian areas (Paper I). During the last 15 years, traffic increase has been very fast in Tartu. However, due to the improvement in vehicle technology during this period, there has been only a slight increase in concentration of exhaust particles (Paper II). Nevertheless, a greater increase in road dust emissions was detected. A statistically significant relationship between long-term exposure to those traffic induced par­tic­les and cardiac disease in the RHINE (Respiratory Health in Northern Europe) Tartu cohort was shown (Paper III). However, no significant associations with respira­tory health were found. The HIA in Tallinn demonstrated 296 (95% CI = 76–528) premature deaths annually, because of PM (Paper IV). The average decrease in life expectancy was predicted to be 0.64 (95% CI 0.17–1.10) years. However, among risk groups it can be higher. In addi­tion, several cardiovascular hospitalizations are related. The costs to society be­cause of health effects reach up to €150 million annually (95% CI = 40–260) from pre­mature deaths and hospitali­zation constitute an additional €0.3 million (95% CI = 0.2–0.4). The special HIA scenario, when more pollution fuel peat will be used in boiler houses was analysed as well (Paper V). It indicated that peat bur­ning would result in up to 55.5 YLL per year within the population of Tartu. However, the health effects of pollution from current traffic, local heating, and industry are at least 28 times bigger. In conclusion, exposure to PM cause considerable health effects in the form of cardio­pulmo­nary diseases in main Estonian cities.
37

O ensino da ressuscitação cardiopulmonar em adultos na graduação em enfermagem: uma revisão integrativa da literatura / Teaching of cardiopulmonary resuscitation in adults for undergraduate nursing students: an integrative literature review

Lourencini, Renata Roque 06 September 2011 (has links)
O ensino de enfermagem em ressuscitação cardiopulmonar (RCP) deve refletir a prática baseada em evidências, as diretrizes da American Heart Assossiation (AHA) e basear-se nos cenários de prática clínica incluindo o reconhecimento da parada cardiorrespiratória, em qualquer ambiente de atenção à saúde. Este estudo trata-se de uma revisão integrativa da literatura e tem como referencial teórico a prática baseada em evidência. Buscou-se identificar e analisar na literatura as evidências oriundas dos estudos primários que abordassem as estratégias de ensino e aprendizagem da RCP em adultos, para os estudantes de graduação em enfermagem. A busca foi realizada nas bases de dados PUBMED, EMBASE, CINAHL e LILACS, no período de 2000 a 2011. Das 591 referências encontradas, 18 estudos primários fizeram parte desta amostra. Foi realizada a extração e análise dos dados, por dois revisores. Foram encontradas as seguintes evidências nos estudos primários: sete de nível II, dois de nível III, dois nível IV e sete estudos de nível VI. Instrução por pares, aprendizagem assistida por computador, aprendizagem baseada em problemas, simulações de alta e baixa finalidade, autoinstrução por leitura de manuais do BLS, autoinstrução por vídeo e a estratégia tradicional têm sido explorados pelos pesquisadores para ensinar e avaliar o nível de aquisição e da retenção dos conhecimentos e das habilidades dos estudantes de enfermagem em RCP. Os estudos de evidência II apresentam comparações entre a estratégia de simulação com o padrão da AHA, com os menequins de média e alta fidelidade, com os estudantes de diferentes níveis de formação; dois estudos comparam estratégias Instrução por pares com a estratégia de ensino tradicional e outro estudo comparando a autoinstrução com a tradicional e com a web-based. O uso da estratégia de simulação com cenários estruturados e com manequins de alta fidelidade mostrou-se, em relação as demais estratégias, a que melhor apresentou subsído para a retenção do conhecimento e aquisição de habilidades na realização da RCP, de acordo com as recomendações das diretrizes da AHA. Os estudos primários mostraram que a retenção do conhecimento e das habilidades apresenta declínio com o passar do tempo, independente da estratégia utilizada pelo professor, sendo necessárias sessões de repetição para que as habilidades não se deteriorem. / Nursing teaching of cardiopulmonary resuscitation (CPR) should reflect the evidence-based practice, the guidelines of the American Heart Association (AHA), and be based on clinical practice scenarios, including the recognition of cardiopulmonary arrest in any environment of health care. This study is an integrative literature review and has the evidence-based practice as the theoretical referential. It aimed to identify and analyze in the literature the evidences from the primary studies that addressed teaching and learning strategies of CPR in adults for undergraduate nursing students. The search was conducted in the PUBMED, EMBASE, CINAHL and LILACS databases in the period from 2000 to 2011. Of the 591 found references, 18 primary studies were part of this sample. Data extraction and analysis were performed by two reviewers. The following evidence in the primary studies were found: seven of level II, three of level III, two of level IV, and six studies of level VI. Peer instruction, computer-assisted learning, problem based learning, high and low-fidelity simulations, self education by reading BLS manual, self education by video and traditional strategy have been explored by researchers to teach and evaluate the level of acquisition and retention of knowledge and skills of nursing students in CPR. Studies of evidence II show comparisons among the simulation strategy with the AHA standard, with the medium and high-fidelity mannequins, and with students of different levels of training; two studies comparing peer instruction strategy with traditional teaching strategy, and another study comparing self education with traditional and web-based strategies. The use of simulation strategy with structured scenarios and high-fidelity mannequins was that showed, in relation to other strategies, better subsidy for the retention of knowledge and skill acquisition in CPR, according to the recommendations and guidelines of the AHA. The primary studies showed that the retention of knowledge and skills declined over time, regardless of the strategy used by the professor, requiring repeated sessions so that skills do not deteriorate.
38

O uso da máscara laríngea pelo enfermeiro na ressuscitação cardiopulmonar: revisão integrativa da literatura / Nurses use of the laryngeal mask in cardiopulmonary resuscitation: an integrative literature review.

Pedersoli, Cesar Eduardo 30 July 2009 (has links)
A parada cardiorrespiratória (PCR) é uma situação que requer atuação imediata dos profissionais da saúde. Na maioria dos hospitais e unidades de saúde, a equipe de enfermagem é a primeira a chegar em casos de PCR, devendo ser competente em iniciar as manobras de ressuscitação cardiopulmonar (RCP). Dentre os procedimentos durante a RCP, a intubação endotraqueal é o padrão ouro para abordagem das vias aéreas, mas nem todos os profissionais de saúde estão aptos a realizá-la. A máscara laríngea é um dispositivo que permite a formação de um selo ao redor da laringe, oferecendo uma satisfatória alternativa para manejo das vias aéreas. O referencial teórico-metodológico utilizado foi o da Prática Baseada em Evidências, que preconiza a aplicação de resultados de pesquisas na prática profissional do enfermeiro. O estudo teve como objetivo identificar as evidências disponíveis na literatura sobre a abordagem de vias aéreas por meio da inserção da máscara laríngea pelo enfermeiro, na RCP, em pacientes adultos. A metodologia adotada foi a revisão integrativa da literatura cujo propósito é reunir e sintetizar o conhecimento sobre a temática proposta. As bases de dados acessadas foram: LILACS, PUBMED, CINAHL e COCHRANE com os descritores controlados laryngeal masks AND cardiopulmonary resuscitation AND nursing. Após leitura exaustiva dos artigos foram selecionadas 18 referencias. Os resultados evidenciaram que 66,5% dos estudos foram oriundos do Reino Unido, o periódico que apresentou maior número de publicações foi a Resuscitation (cinco), 50% dos estudos foram realizados somente por médicos, 28% somente por enfermeiros e 11% por ambos, conjuntamente. Em relação ao delineamento de pesquisa foram encontrados seis estudos (33,5%) de delineamento quaseexperimental, 12 (66,5%) de delineamento não-experimental, sendo três do tipo survey/descritivo/exploratório (25%), um prospectivo (8,5%) e oito relatos de experiência/opinião de especialista (66,5%). Os estudos foram agrupados em três momentos históricos (antes da publicação das diretrizes de RCP de 2000, entre as diretrizes de 2000 e 2005 e após as diretrizes de 2005). Verificou-se que o grande impacto dos estudos publicados na década de 90 foi evidenciado nas diretrizes de 2005, pois as embasaram e foram citados nas mesmas (estudos 1, 2, 3, 5, 7 e 9). Conclui-se que a mascara laríngea é de fundamental importância para manejo de vias aéreas em situações criticas, necessita de treinamento para sua utilização e, quando testada em manequins, mostrou-se eficaz, atingindo taxas de sucesso em sua inserção e nas ventilações, próximas a 100%. É um dispositivo de fácil manuseio e inserção, minimiza o risco de distensão gástrica, regurgitação e aspiração em relação à unidade bolsa-valva-máscara. A ausência de estudos com delineamento experimental acerca da temática, evidencia a necessidade de investigações cientificas envolvendo mascara laríngea, ressuscitação cardiopulmonar e enfermagem, com o intuito de subsidiar a pratica clínica do enfermeiro e sua tomada de decisão acerca do cuidado prestado ao paciente. Os enfermeiros atuaram nos estudos como sujeitos e puderam identificar, compreender e sinalizar aspectos relevantes dos atributos cognitivo, técnicos e demais habilidades para executarem tal intervenção, permitindo-se prestar assistência de enfermagem com qualidade e embasamento técnico-científico em situações de emergência. / Heart arrest (HA) is a situation that demands immediate action from health professionals. In most hospitals and health units, the nursing team is the first to arrive in cases of HA, and should be competent to start cardiopulmonary resuscitation (CPR) maneuvers. In CPR procedures, endotracheal intubation is the gold standard for the airways, but not all health professionals are apt to perform this procedure. The laryngeal mask is a device that permits forming a seal around the larynx, offering a satisfactory alternative for airway management. The theoretical-methodological reference framework of Evidence-Based Practice was used, which recommends that research results be applied in nurses professional practice. This study aimed to identify available evidence in literature about airway management by nurses through the insertion of the laryngeal mask, during CPR, in adult patients. The integrative literature review method was adopted, which aims to join and synthesize knowledge on the proposed theme. The following databases were accessed: LILACS, PUBMED, CINAHL and COCHRANE, using the controlled descriptors laryngeal masks AND cardiopulmonary resuscitation AND nursing. After exhaustive reading of the articles, 18 references were selected. The results evidenced that 66.5% of the studies came from the United Kingdom; the journal with the largest number of publications was Resuscitation (five); 50% of the studies was performed by physicians only, 28% by nurses only and 11% by both, in cooperation. As to research design, six studies (33.5%) had a quasiexperimental design and 12 (66.5%) a non-experimental design, with three survey/descriptive/exploratory studies (25%), one prospective study (8.5%) and eight experience reports/expert opinions (66.5%). Studies were grouped at three moments in time (before the publication of the 2000 CPR guidelines, between the 2000 and 2005 guidelines and after the 2005 guidelines). The strong impact of the studies published in the 1990s was evidenced in the 2005 guidelines, which constituted the base and were cited in that document (studies 1, 2, 3, 5, 7 and 9). It is concluded that the laryngeal mask is fundamentally important for airway management in critical situations, requires training for its use and showed its efficiency when tested on manikins, reaching success levels of nearly 100% for insertion and ventilations. The device is easy to manage and insert, minimizes the risk of gastric distension, regurgitation and aspiration of the bag-valve-mask unit. The lack of studies about the theme with an experimental design evidences the need for scientific research involving laryngeal mask, cardiopulmonary resuscitation and nursing, with a view to supporting clinical nursing practice and nurses decision making about patient care delivery. Nurses participated in the studies and could identify, understand and signal relevant aspects of the cognitive and technical attributes and other skills to perform this intervention, with a view to nursing care delivery with quality and theoretical-scientific support in emergency situations.
39

Crenças dos enfermeiros de unidades diagnósticas sobre o atendimento à parada cardiorrespiratória / Nurses\' beliefs on managing cardiopulmonary arrest in the diagnosis unit

Hadi, Hafiza Abdon Musser 28 March 2008 (has links)
Este estudo, de cunho qualitativo, objetivou verificar as estruturas de atendimento à parada cardiorrespiratória e identificar as crenças pessoais e normativas dos enfermeiros que atuam em unidades diagnósticas, utilizando como referencial teórico a Teoria da Ação Racional (Theory of Reasoned Action - TRA). Os dados foram obtidos por meio de entrevistas semi-estruturadas, junto a dezesseis enfermeiros de unidades diagnósticas de três hospitais privados e um público da cidade de São Paulo. Os dados foram submetidos à técnica de análise de conteúdo, que possibilitou evidenciar crenças positivas e negativas agrupadas em duas Unidades Temáticas Centrais, estabelecidas \"a priori\", dentro dos pressupostos da TRA: Crenças de Atitude e Crenças Normativas. A análise das entrevistas evidenciou que entre as Crenças de Atitude, destacaram-se as crenças afetivas negativas em relação à execução do comportamento. Na unidade Crenças Normativas, foram evidenciados os referentes sociais positivos para a execução do comportamento: grupo de parada, equipe de enfermagem, médico do grupo de parada, médico anestesista, bem como os fatores estimuladores do comportamento: conhecimento e preparo dos médicos, treinamentos freqüentes, equipamentos disponíveis, atrelar o \"bip\" dos enfermeiros ao do grupo de parada; como referentes sociais que desestimulam o comportamento: equipe médica e de enfermagem, e, como fatores que desestimulam: planta física, déficit de conhecimento dos médicos e equipe de enfermagem e recursos humanos deficitários. Concluiu-se que é imprescindível que os programas educacionais sejam elaborados a partir de fatores que motivem, possibilitem e reforcem o enfermeiro a adotar determinado comportamento, tornando este profissional capaz de participar dos processos decisórios que envolvem o cuidado do paciente crítico, junto aos seus pares, de forma igualitária, tornando o atendimento seguro e eficaz ao paciente / This study, on a qualitative stamp, aimed at verifying the structures of managing cardiopulmonary arrest (CPA) and identifying the personal and normative beliefs of nurses working in diagnosis units, using the Theory of Reasoned Action - (TRA) as a theoretical framework. The data were obtained through semi-structured interviews from sixteen diagnosis unit nurses of four hospitals (three private and one public) in Sao Paulo city. The data were submitted to a content analysis technique, attesting negative and positive beliefs which were grouped into two Central Thematical Units established beforehand within the estimated TRA: Attitude and Normative Beliefs. The analysis of the interviews proved that among the Attitude Beliefs, the negative affective beliefs stood out as far as the behavior performance is concerned. In the Normative Belief Units, when analyzed the behavior performances, the following positive social referents were evidenced: (CPA) group, nursing team, (CPA) group physician, anesthesia physician, as well as the behavior\'s stimulating factors: the physicians\' knowledge and skill, frequent training, equipment available, attaching the nurses\' bippers to the (CPA) group; as social referents which discourage the behavior: medical and nursing team, and as discouraging factors: hospital facility area, physicians\' lack of knowledge and deficitary nursing team and human resources. As a conclusion, it is observed that the educational programs must be developed from factors which motivate, allow and reinforce the nurse to take a certain procedure, making this professional capable of participating on the decisive processes that involve the care for critical patients, together with his/her peers in a equalitarian way, making this care safe and effective to the patient
40

Modeling and Estimation of Cardiorespiratory Function, with Application to Mechanical Ventilation

Karamolegkos, Nikolaos January 2018 (has links)
Evidence-based medicine is at the heart of current medical practice where clinical decisions are driven by research data. However, most current therapy recommendations follow generalized protocols and guidelines that are based on epidemiological (population) studies and thus not suited for the individual patient's demands. Patient-tailored therapies are considered, hence, an unmet clinical need. We believe that mathematical models of the physiology can attend to such a clinical need, because they can be tuned to the individual patient. Such models provide a sound mathematical framework for personalized clinical decisions. In particular, physiological models in medicine can serve the following two purposes: 1) They can be an efficient tool to quantify cardiopulmonary dynamics, conduct virtual clinical/physiological experiments, and investigate the effects of specific treatments. 2) Model-based estimation techniques can assess physiological parameters or variables, which are otherwise impractical or dangerous to measure; they can effectively tune a generic model to become patient-specific, able to mimic the behavior of a particular patient. In this thesis, we propose a series of modifications to a previously developed cardiopulmonary model (CP Model) in order to better replicate heart-lung interaction phenomena that are typically observed under mechanical ventilation, hence allowing for a more accurate analysis of ventilation-induced changes in cardiac function. The response of this modified model is validated with experimental data collected during mechanical ventilation conditions. Further, as an industrial application of mathematical models, we present a patient emulator system that comprises the modified CP Model, a physical ventilator, and a piston-cylinder arrangement that serves as an electrical-to-hydraulic transducer. The modified CP Model then serves as the virtual patient that is being ventilated, where disease conditions can be instilled. Such a system is designed to offer a well-controlled experimental environment for ventilator manufacturers to efficaciously test and compare ventilation modalities and therapies, thereby enhancing their verification and validation manufacturing processes. Finally, we develop a model-based approach to estimate (noninvasively) the function of the cardiovascular system, in terms of cardiac performance (i.e., cardiac output) and the dynamics of the systemic arterial tree (i.e., time constant). With this technique, we envision to provide continuous and real-time bedside monitoring of changes in cardiovascular function, such as those induced by changes in ventilator settings.

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