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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.
11

Automated algorithms for detection of stroke distance from Doppler ultrasound signals

Warner, Margaret January 1999 (has links)
No description available.
12

Health Risk Feedback: The Effects of ACE Insight on Stress Reactivity

Rued, Heidi Anna January 2018 (has links)
Exposure to adverse childhood experiences (ACEs) has lasting repercussions throughout an individual’s lifetime. An adult with a history of childhood trauma is at increased risk for excessive stress reactivity, which exacerbates the development of chronic disease. It is important to investigate how this information can be used for adult trauma survivors. This study assessed the psychophysiological impacts of providing “ACE insight”. Participants completed questionnaires and were given false feedback that their childhood experiences put them at increased risk for excessive stress reactivity and the development of disease. Following ACE insight, participants underwent a speech stressor task during which cardiovascular reactivity was monitored and psychological reactions were assessed. Results indicated that participants with more adverse childhoods reported feeling more worried and less happy about feedback. Further, ACE insight caused a significant increase in cardiac output for participants with a history of childhood trauma. Implications and future directions are discussed.
13

Determination of cardiac output across a range of values in horses by M-mode echocardiography and thermodilution

Moore, Donna Preston 15 March 2004 (has links)
Determinations of cardiac output (CO) by M-mode echocardio-graphy were compared with simultaneous determinations by thermodilution in 2 conscious and 5 anesthetized horses. A range of cardiac outputs was induced by use of a pharmacological protocol (dopamine, 4 ug/kg/min, dobutamine, 4 ug/kg/min, and 10 ug/kg detomidine plus 20 ug/kg butorphanol, in sequence). Changes from baseline CO in response to each drug were evaluated, and data was analyzed to determine whether there were any interactions between drug treatment and measurement method. The mathematical relationship between CO as determined by M-mode echocardio-graphy (COecho) and as determined by thermodilution (COTD) was described and used to predict COTD from COecho. The 2 methods were compared with respect to bias and variability in order to determine the suitability of COecho as a substitute for COTD . Sources of the variability for each method were determined. Determination of CO by either method in standing horses was prohibitively difficult due to patient movement. The pharmacologi-cal protocol was satisfactory for inducing a range of cardiac outputs for the purpose of method comparison; however, use of dopamine did not offer any additional benefit over the use of dobutamine and was generally less reliable for increasing CO. Inclusion of detomidine provided an additional change in CO but did not increase the overall range of CO over that produced by halothane and dobutamine. COecho and COTD were significantly related by the predictive equation COTD = (0.63 +/- 0.157) x COecho + (16.6 +/- 3.22). The relatively large standard errors associated with COecho measurements resulted in a broad 95% prediction interval such that COecho would have to change by more than 100% in order to be 95% confident that the determined value represents true hemodynamic change. COecho underestimated COTD by a mean of 10 +/- 6.3 l/min/450 kg. The large standard deviation of the bias resulted in broad limits of agreement (-22.3 to +2.3 l/min/450 kg). Measurement-to-measurement variability accounted for 28% of the total variation in COTD values and 64% of the total variation in COecho values. Results might be improved if the mean of 3-5 consecutive beats was used for each measurement, but as determined in this experiment, COecho is too variable to have confidence in its use for precise determinations of CO. / Master of Science
14

EFFECT OF ROOM TEMPERATURE AND ICED INJECTATES ON MEASUREMENT OF THERMODILUTION CARDIAC OUTPUT.

Miller, Patty L. January 1984 (has links)
No description available.
15

THE INVESTIGATION OF A CONTINUOUS HEATING/COOLING TECHNIQUE FOR CARDIAC OUTPUT MEASUREMENT.

Ehlers, Kevin Charles. January 1984 (has links)
No description available.
16

Development of a realistic in vitro model for studying the energetics of cardiac papillary muscles

Mellors, Linda Jane, 1974- January 2001 (has links)
Abstract not available
17

Non-invasive Cardiac Output of Children in Health and Disease: Respiratory Gas Techniques

Schneiderman, Jane 11 January 2012 (has links)
Cardiac output (Q) is an important determinant of the cardiovascular system‟s ability to meet the oxygen needs of the body. This dissertation addresses the non-invasive measurement of Q, in healthy children and those with heart and lung disease. 1) The correction factors for collision broadening, downstream difference and end tidal CO2 (PetCO2), used in the CO2 rebreathe (equilibrium) method, were evaluated. In lung disease, one is unable to assume a normal dead space to estimate arterial CO2 (PaCO2), and the use of any of these correction factors alone should be used with caution as they each exert a profound effect on the Q measurement. 2) A new equation to predict PaCO2 from PetCO2 in patients with CF was derived via multiple regression analysis, taking into account disease severity. 3) The validity and reliability of Q measures via the inert gas rebreathing technique (InnocorTM device) were evaluated. The highest intraclass correlation coefficients were attained during exercise (0.7-0.98), indicating excellent reliability of the device. Comparisons of Q measures from the InnocorTM (QInn) to the AMIS mass spectrometer system (QAmis) were made to assess validity. The bias (QInn-QAmis) and limits of agreement (±2SD) were 0.45 ± 1.9 L.min-1 and 0.27 ± 2.1 for children with congenital heart disease and healthy controls respectively, with no systematic differences between the two methods. 4) Assessment of cardiac output in Fontan patients demonstrated that an individualized, atrioventricular (AV) delay optimization was required. Moreover, there was a small but significant improvement in heart function with AV synchronized pacing (DDI) versus ventricular pacing (VVI), suggesting that further study with a larger sample of patients is warranted. The limitations and strengths of the measurement of non-invasive cardiac output in children, primarily via respiratory gas analysis, were delineated and recommendations were made for their use.
18

Non-invasive Cardiac Output of Children in Health and Disease: Respiratory Gas Techniques

Schneiderman, Jane 11 January 2012 (has links)
Cardiac output (Q) is an important determinant of the cardiovascular system‟s ability to meet the oxygen needs of the body. This dissertation addresses the non-invasive measurement of Q, in healthy children and those with heart and lung disease. 1) The correction factors for collision broadening, downstream difference and end tidal CO2 (PetCO2), used in the CO2 rebreathe (equilibrium) method, were evaluated. In lung disease, one is unable to assume a normal dead space to estimate arterial CO2 (PaCO2), and the use of any of these correction factors alone should be used with caution as they each exert a profound effect on the Q measurement. 2) A new equation to predict PaCO2 from PetCO2 in patients with CF was derived via multiple regression analysis, taking into account disease severity. 3) The validity and reliability of Q measures via the inert gas rebreathing technique (InnocorTM device) were evaluated. The highest intraclass correlation coefficients were attained during exercise (0.7-0.98), indicating excellent reliability of the device. Comparisons of Q measures from the InnocorTM (QInn) to the AMIS mass spectrometer system (QAmis) were made to assess validity. The bias (QInn-QAmis) and limits of agreement (±2SD) were 0.45 ± 1.9 L.min-1 and 0.27 ± 2.1 for children with congenital heart disease and healthy controls respectively, with no systematic differences between the two methods. 4) Assessment of cardiac output in Fontan patients demonstrated that an individualized, atrioventricular (AV) delay optimization was required. Moreover, there was a small but significant improvement in heart function with AV synchronized pacing (DDI) versus ventricular pacing (VVI), suggesting that further study with a larger sample of patients is warranted. The limitations and strengths of the measurement of non-invasive cardiac output in children, primarily via respiratory gas analysis, were delineated and recommendations were made for their use.
19

The effects of prior exercise and varied rest intervals upon cardiorespiratory endurance performance /

Andzel, Walter Dennis. January 1976 (has links)
Thesis (Ed.D.)--Teachers College, Columbia University, 1976. / Typescript; issued also on microfilm. Sponsor: Bernard Gutin. Dissertation Committee: Kenneth J. Simon, Kerry Stewart. Includes bibliographical references (leaves 51-54).
20

DECREASED CARDIAC OUTPUT RISK: characterization of proposal of nursing diagnosis / Risco para dÃbito cardÃaco diminuÃdo: caracterizaÃÃo de proposta de diagnÃstico de enfermagem

Renata Pereira de Melo 29 August 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The study looked to characterize a proposal for the nursing diagnosis of âRisk of Decreased Cardiac Outputâ, based on the judgement of 25 specialists. It was carried out in the period of September of 2007 to April of 2008, in two methodological stages: a) Elaboration of the proposal of the nursing diagnosis of Risk of Decreased Cardiac Output, according to NANDA, and the operational definition for each risk factor; b) Validation of the concept, of the risk factors and the operational definitions. For so, it was used the Diagnostic Content Validation model proposed by Fehring and the Delphi technique. All the specialists were selected based on Fehringâs criteria. Data was collected at two moments, from questionnaires. The quantitative analysis disposed of the calculation of the weighted mean of the value attributed by specialist to each risk factor, being: 1 (it does not cause vulnerability) = 0; 2 (it causes very little vulnerability) = 0,25; 3 (it causes moderate vulnerability) = 0,5; 4 (it causes very much vulnerability) = 0,75; and 5 (it completely causes vulnerability) = 1. Based on this calculation, the risk factors with score below the established cutoff point of 0,6 were discarded. For the evaluation of the items related to the operational definition (Clarity, Adequacy to the risk factor and Adequacy to the remaining proposed terms) the values were tabulated (+1, 0 and -1) and the mean calculated, in order to check the level of agreement/disagreement between the specialists. There was still calculated the Index of Content Validity, which indicates the confidence of the application of the diagnosis in practice. It was considered the explanation of the objectives to the participants, their declared consent in allowing the collection and supplying the solicited data, their freedom to refuse or give up from participating in any phase of the research process without prejudice of any kind to them, to ask for clarification as well as their right to anonymity. As result, was obtained the understanding that the label proposed is representative of a nursing diagnosis, to which the concept corresponded, in adequacy to the structure used by NANDA: âTo be in risk of developing a level of health characterized by insufficient quantity of blood pumped each minute by the heart to fulfill the physical metabolic demandsâ. Were considered representative risk factor for this phenomenon (≥ 0,6), according to the specialists judgement: myocardial dysfunction (0,887), blood loss (0,875), intrapericardial pressure increase (0,825), condition that causes alteration in the rhythm and/or electric cardiac driving (0,812), defective volume of liquids (0,725), plasma loss (0,712), ineffective tissular perfusion (0,712), electrolytic unbalance (0,7), acid-base unbalance (0,697), valve alteration (0,65), major surgery (0,65) and general deep anaesthesia/spinal anaesthesia (0,625), obtaining a Index of Content Validity of 0,739. With this proposal, it was provided the characterization of this phenomenon, as a form to orientate the process of clinical judgement, making possible a preventive act, as a way to avoid the development of the real entity and of his complications. However, because of the peculiarity of this study and the relevance of its finds, itâs essential the replication of the 10 risk factors (22%) that were located between the cutoff points of 0,5 and 0,59, as well as new submissions of the data to the specialists to obtain the consensus, and the realization of a study of clinical validation, in order to obtain evidences about the incident of this phenomenon in nursesâ practice / O estudo buscou caracterizar proposta para o diagnÃstico de enfermagem Risco para DÃbito CardÃaco diminuÃdo, com base no juÃzo de 25 especialistas. Foi realizado no perÃodo de setembro de 2007 a abril de 2008, em duas etapas metodolÃgicas: a) ElaboraÃÃo da proposta do diagnÃstico de enfermagem Risco para DÃbito CardÃaco diminuÃdo, de acordo com a NANDA, e da definiÃÃo operacional para cada fator de risco; b) ValidaÃÃo do construto, dos fatores de risco e das definiÃÃes operacionais. Para tanto, utilizou o modelo de ValidaÃÃo de ConteÃdo DiagnÃstico de Fehring e a tÃcnica Delphi. Todos os especialistas foram selecionados com base nos critÃrios de Fehring. Os dados foram coletados em dois momentos, por meio de questionÃrio. Jà a anÃlise quantitativa empregou a mÃdia ponderada do valor atribuÃdo por especialista a cada fator de risco, sendo: 1 (nÃo causador de vulnerabilidade) = 0; 2 (pouco causador de vulnerabilidade) = 0,25; 3 (moderadamente causador de vulnerabilidade) = 0,5; 4 (muito causador de vulnerabilidade) = 0,75; e 5 (totalmente causador de vulnerabilidade) = 1. Com base nesse cÃlculo, descartaram-se os fatores de risco com escore abaixo do ponto de corte estabelecido de 0,6. Para a avaliaÃÃo dos itens relacionados à definiÃÃo operacional (Clareza, AdequaÃÃo ao fator de risco e AdequaÃÃo aos demais termos propostos) seus valores foram tabulados (+1, 0 e -1) e a mÃdia calculada, com vistas a verificar o nÃvel de concordÃncia/discordÃncia entre os especialistas. Calculou-se ainda o Ãndice de Validade de ConteÃdo, o qual indica a confianÃa da aplicaÃÃo do diagnÃstico na prÃtica. Considerou-se o esclarecimento dos objetivos e da metodologia aos participantes, o consentimento declarado destes em permitir a coleta e fornecer os dados solicitados, a sua liberdade para recusar ou desistir de participar em qualquer fase do processo de pesquisa sem prejuÃzo de qualquer natureza à sua pessoa, assim como para solicitar esclarecimentos e o seu direito ao anonimato. Como resultado, obteve-se a compreensÃo do rÃtulo proposto como representativo de um diagnÃstico de enfermagem, para o qual prevaleceu o construto: âEstar em risco de desenvolver um estado de saÃde caracterizado por quantidade insuficiente de sangue bombeado pelo coraÃÃo a cada minuto para atender Ãs demandas metabÃlicas corporaisâ. Foram considerados fatores de risco representativos deste fenÃmeno (≥ 0,6), segundo o juÃzo dos especialistas: disfunÃÃo miocÃrdica (0,887), perda sangÃÃnea (0,875), aumento da pressÃo intrapericÃrdica (0,825), condiÃÃo que causa alteraÃÃo no ritmo e/ou conduÃÃo elÃtrica cardÃaca (0,812), Volume de LÃquidos deficiente (0,725), perda plasmÃtica (0,712), PerfusÃo Tissular ineficaz (0,712), desequilÃbrio eletrolÃtico (0,7), desequilÃbrio acidobÃsico (0,697), alteraÃÃo valvar (0,65), grandes cirurgias (0,65) e anestesia geral profunda/ anestesia espinhal (0,625), obtendo-se um Ãndice de Validade de ConteÃdo de 0,739. Com esta proposta, propiciou-se a caracterizaÃÃo deste fenÃmeno, como forma de orientar o processo de julgamento clÃnico, possibilitando uma atuaÃÃo de cunho preventivo, de modo a evitar o desenvolvimento da entidade real e das suas complicaÃÃes. No entanto, em virtude da sua singularidade e da relevÃncia dos seus achados, à imprescindÃvel a replicaÃÃo dos 10 fatores de risco (22%) situados entre os pontos de corte de 0,5 e 0,59, assim como novas submissÃes dos dados aos especialistas para a obtenÃÃo do consenso e a realizaÃÃo de estudo de validaÃÃo clÃnica, a fim de obter evidÃncias acerca da ocorrÃncia desse fenÃmeno na prÃtica dos enfermeiros

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