Gu, Wenbo. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references. / Abstract also in Chinese. / Acknowledgment --- p.i / Abstract --- p.ii / 摘要 --- p.iii / List of Figures --- p.vi / List of Tables --- p.vii / List of Abbreviations --- p.viii / Contents --- p.ix / Chapter 1. --- Introduction --- p.1 / Chapter 1.1. --- Arterial blood pressure and its importance --- p.1 / Chapter 1.2. --- Current methods for non-invasive blood pressure measurement --- p.4 / Chapter 1.2.1. --- The auscultatory method (mercury sphygmomanometer) --- p.4 / Chapter 1.2.2. --- The oscillometric method --- p.5 / Chapter 1.2.3. --- The tonometric method --- p.7 / Chapter 1.2.4. --- The volume-clamp method --- p.7 / Chapter 1.3. --- Blood pressure estimation based on pulse arrival time --- p.8 / Chapter 1.4. --- Objectives and structures of this thesis --- p.10 / Chapter 2. --- Hemodynamic models: relationship between PAT and BP --- p.14 / Chapter 2.1. --- The generation of arterial pulsation --- p.14 / Chapter 2.2. --- Pulse wave velocity along the arterial wall --- p.15 / Chapter 2.2.1. --- Moens-Korteweg equation --- p.15 / Chapter 2.2.2. --- Bergel wave velocity --- p.18 / Chapter 2.3. --- Relationship between PWV and BP --- p.19 / Chapter 2.3.1. --- Bramwell-Hill´ةs model --- p.20 / Chapter 2.3.2. --- Volume-pressure relationship --- p.20 / Chapter 2.3.3. --- Hughes' model --- p.22 / Chapter 2.4. --- The theoretical expression of PAT-BP relationship --- p.23 / Chapter 3. --- Estimation and calibration of arterial BP based on PAT --- p.25 / Chapter 3.1. --- PAT measurement --- p.25 / Chapter 3.1.1. --- Principle of ECG measurement --- p.25 / Chapter 3.1.2. --- Principle of PPG measurement --- p.26 / Chapter 3.1.3. --- Calculation of PAT --- p.28 / Chapter 3.2. --- Calibration methods for PAT-BP estimation --- p.29 / Chapter 3.2.1. --- Calibration based on cuff BP readings --- p.30 / Chapter 3.2.2. --- Calibration by hydrostatic pressure changes --- p.31 / Chapter 3.2.3. --- Calibration by multiple regression --- p.33 / Chapter 3.3. --- Model-based calibration with PPG waveform parameters --- p.34 / Chapter 3.3.1. --- Model-based equation with parameters from PPG waveform --- p.34 / Chapter 3.3.2. --- Selection of parameters from PPG waveform --- p.36 / Chapter 4. --- Cuffless calibration approach using PPG waveform parameter for PAT-BP estimation --- p.43 / Chapter 4.1. --- Introduction --- p.43 / Chapter 4.2. --- Experiment I: young group in sitting position including rest and after exercise states --- p.43 / Chapter 4.2.1. --- Experiment protocol --- p.43 / Chapter 4.2.2. --- Data Analysis --- p.44 / Chapter 4.2.3. --- Experiment results --- p.46 / Chapter 4.3. --- Experiment II: over-month observation using wearable device in sitting position --- p.48 / Chapter 4.3.1. --- Body sensor network for blood pressure estimation --- p.49 / Chapter 4.3.2. --- Experiment protocol and data collection --- p.50 / Chapter 4.3.3. --- Experiment results --- p.50 / Chapter 4.4. --- Experiment III: contactless monitoring in supine position --- p.51 / Chapter 4.4.1. --- The design of the contactless system --- p.52 / Chapter 4.4.2. --- Experiment protocol and data collection --- p.53 / Chapter 4.4.3. --- Experiment results --- p.53 / Chapter 4.5. --- Discussion --- p.55 / Chapter 4.5.1. --- Discussion of Experiments I and II --- p.55 / Chapter 4.5.2. --- Discussion of Experiments II and III --- p.57 / Chapter 4.5.3. --- Conclusion --- p.58 / Chapter 5. --- Cuff-based calibration approach for BP estimation in supine position --- p.61 / Chapter 5.1. --- Introduction --- p.61 / Chapter 5.2. --- Experiment protocol --- p.61 / Chapter 5.2.1. --- Experiment IV: exercise experiment in supine position in lab --- p.61 / Chapter 5.2.2. --- Experiment V: exercise experiment in supine position in PWH --- p.63 / Chapter 5.3. --- Data analysis --- p.65 / Chapter 5.3.1. --- Partition of signal trials and selection of datasets --- p.65 / Chapter 5.3.2. --- PPG waveform processing --- p.66 / Chapter 5.4. --- Experiment results --- p.68 / Chapter 5.4.1. --- Range and variation of reference SBP --- p.68 / Chapter 5.4.2. --- PAT-BP individual best regression --- p.69 / Chapter 5.4.3. --- Multiple regression using ZX and arm length --- p.72 / Chapter 5.4.4. --- One-cuff calibration improved by PPG waveform parameter --- p.72 / Chapter 5.5. --- Discussion --- p.74 / Chapter 6. --- Conclusion --- p.76

Yan, Renfei. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 69-77). / Abstract also in Chinese. / ABSTRACT --- p.I / ACKNOWLEDGEMENT --- p.V / LIST OF FIGURES --- p.VI / LIST OF TABLES --- p.VIII / LIST OF ABBREVIATIONS --- p.IX / Chapter CHAPTER 1. --- INTRODUCTION TO BLOOD PRESSURE MEASURING DEVICES AND EVALUATION STANDARDS --- p.1 / Chapter 1.1. --- Current situation on hypertension --- p.1 / Chapter A. --- Prevalence of hypertension --- p.1 / Chapter B. --- Low awareness of hypertension --- p.1 / Chapter 1.2. --- Calls for better management of hypertension --- p.2 / Chapter 1.3. --- Blood pressure measuring devices --- p.3 / Chapter A. --- Conventional devices and their limitations --- p.3 / Chapter B. --- Wearable cuff-less devices --- p.4 / Chapter 1.4. --- Evaluation of the wearable cuff-less devices --- p.6 / Chapter 1.5. --- Objectives of the thesis --- p.7 / Chapter 1.6. --- Structure of the thesis --- p.7 / Chapter CHAPTER 2. --- REVIEW ON CURRENT STANDARDS --- p.8 / Chapter 2.1. --- Introduction to current standards --- p.8 / Chapter A. --- AAMI standard --- p.8 / Chapter B. --- BHS protocol --- p.8 / Chapter C. --- ESH protocol --- p.9 / Chapter 2.2. --- Comparison of current standards --- p.9 / Chapter A. --- Evaluation scope --- p.9 / Chapter B. --- Validation protocol --- p.10 / Chapter C. --- Accuracy criteria --- p.10 / Chapter D. --- Testing reference --- p.13 / Chapter E. --- Recruitment of subjects --- p.13 / Chapter F. --- Ambulatory monitors --- p.14 / Chapter G. --- Special groups of population --- p.15 / Chapter H. --- Statistical considerations --- p.16 / Chapter 2.3. --- Major challenges for the evaluation of cuff-less devices --- p.17 / Chapter A. --- Lack of experimental data --- p.19 / Chapter B. --- Re-examination of the statistical considerations --- p.19 / Chapter C. --- Feature oriented design of the validation protocol --- p.19 / Chapter D. --- Selection of testing reference --- p.79 / Chapter CHAPTER 3. --- ERROR DISTRIBUTION MODEL --- p.21 / Chapter 3.1. --- Distribution assumption in current standards --- p.21 / Chapter 3.2. --- Distribution analysis from published reports --- p.22 / Chapter A. --- Methodology --- p.22 / Chapter B. --- Data analysis --- p.23 / Chapter C. --- Results --- p.23 / Chapter 3.3. --- Distribution analysis on a cuff-less device --- p.29 / Chapter A. --- Experiment --- p.29 / Chapter B. --- Data analysis --- p.31 / Chapter C. --- Results --- p.31 / Chapter 3.4. --- Discussion --- p.33 / Chapter A. --- Supporting evidence for t4 distribution --- p.33 / Chapter B. --- Implications for the application of t4 distribution --- p.34 / Chapter 3.5. --- Section Summary --- p.35 / Chapter CHAPTER 4. --- EVALUATION SCALE TO ASSESS THE ACCURACY --- p.36 / Chapter 4.1. --- Considerations for parameter selection --- p.37 / Chapter A. --- Outlying errors and system bias --- p.37 / Chapter B. --- Accuracy at different levels of blood pressure --- p.37 / Chapter 4.2. --- Description of selected parameters --- p.38 / Chapter 4.3. --- Theoretical relationship between “new´ح and “old´ح parameters --- p.38 / Chapter A. --- Mathematical relationship --- p.39 / Chapter B. --- Mapping relationship --- p.40 / Chapter 4.4. --- Assessment of accuracy at increasing blood pressure levels --- p.41 / Chapter A. --- Data transformation --- p.41 / Chapter B. --- Experimental study --- p.41 / Chapter 4.5. --- Discussion and application --- p.43 / Chapter A. --- Parameter selection --- p.43 / Chapter B. --- Sample size --- p.45 / Chapter C. --- Accuracy criteria --- p.46 / Chapter 4.6. --- Section summary --- p.47 / Chapter CHAPTER 5. --- FEATURE ORIENTED PROTOCOL DESIGN --- p.48 / Chapter 5.1. --- Rationale of accuracy assessment with BP change --- p.48 / Chapter 5.2. --- Experiment one --- p.49 / Chapter 5.3. --- Experiment two --- p.49 / Chapter 5.4. --- Data analysis --- p.49 / Chapter 5.5. --- Results --- p.50 / Chapter A. --- Experiment one --- p.50 / Chapter B. --- Experiment two --- p.52 / Chapter 5.6. --- Discussion --- p.58 / Chapter A. --- Difference between cuff-less and cuff-based devices --- p.58 / Chapter B. --- Correlation between accuracy and blood pressure changes --- p.58 / Chapter C. --- Inducement of blood pressure change --- p.59 / Chapter D. --- Other factors affect the accuracy --- p.60 / Chapter 5.7. --- Section summary --- p.61 / Chapter CHAPTER 6. --- PROPOSAL FOR THE EVALUATION OF WEARABLE CUFF-LESS DEVICES --- p.62 / Chapter 6.1. --- Scope --- p.62 / Chapter 6.2. --- Purpose --- p.62 / Chapter 6.3. --- Subject selection --- p.63 / Chapter 6.4. --- Main validation --- p.64 / Chapter A. --- Static test --- p.64 / Chapter B. --- Test with blood pressure change --- p.65 / Chapter C. --- Test after a certain period of time --- p.65 / Chapter 6.5. --- Data analysis and reporting --- p.66 / Chapter A. --- Statistical report --- p.66 / Chapter B. --- Graphical representation --- p.67 / Chapter 6.6. --- Conclusion and future work --- p.67 / REFERENCES --- p.69 / LIST OF PUBLICATIONS AND AWARDS --- p.78

The value to consider user needs throughout the development of medical devices has been acknowledged in the field of health technology assessment. Yet, user needs are narrowly conceptualised and are mainly examined from an ergonomic perspective. By focusing on the user-device interaction per se with a view to detect use errors and to create design solutions that promote intended use, the dominant approach to user needs research fails to adequately elaborate upon symbolic and practice-related dimensions in the user-technology relationship. Moreover, whilst the examination of user needs from a User standpoint is clearly required, it is also crucial to investigate how the medical device industry understands and addresses this issue, since it is these understandings that will eventually be projected onto the technology. The present research sought to provide a cross-actor account on the issue of user needs by examining the perspectives of two key stakeholders: the users and the medical device manufacturer. Using the example of home blood pressure (BP) monitoring, a qualitative programme of research explored, on the one hand, the process of integrating home blood pressure monitors (HBPMs) into daily life as well as the elements that are conducive to building trust in this technology, and on the other, the practices the medical device manufacturer adopts to capture its users and their needs. The results suggest that people engage with home BP monitoring in an effort to develop an experiential understanding of their health condition reproducing the dominant discourse around the benefits of self-care. Nevertheless, communicating this practice outside the home was not always without tension since concerns around the ascription of undesired identities were expressed. Home measurements were occasionally performed to check the dependability of technology – arguably an unintended device use – indicating the importance of establishing trust in the artefact. Building trust in HBPMs appeared to be a multifaceted phenomenon that was not limited to the perceived trustworthiness of the technology but implicated a network of other trustworthy relationships with humans, institutions and technologies. Medium-to-large medical device manufacturers appear to appreciate the value of a user needs-informed approach to medical device development employing a series of routes, more or less direct and formalised, to reach their user. The challenge for the industry is to synthesise the evidential base deriving from individual user studies to create a higher order knowledge base. The term ‘symbolic’ – also employed in the title of this thesis – signifies people’s representations, reasoning and meanings constructed around the use or production of home medical technology whilst the term ‘practical’ (or practice-related) refers to actions, activities, and routines pertaining to these two aspects.

京都大学 / 0048 / 新制・課程博士 / 博士(社会健康医学) / 甲第19969号 / 社医博第74号 / 新制||社医||9(附属図書館) / 33065 / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 小池 薫, 教授 福田 和彦, 教授 木村 剛 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM

Orientador: José Luiz Tatagiba Lamas / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-20T22:31:22Z (GMT). No. of bitstreams: 1 Gothardo_AnaCarolinaLopesOttoni_M.pdf: 3169615 bytes, checksum: da99c78d906df92371167a9e0c7c0502 (MD5) Previous issue date: 2012 / Resumo: A medição da pressão arterial em setores de emergência e cuidados intensivos é um procedimento utilizado para avaliar com rapidez a condição do paciente e direcionar a conduta terapêutica. Devido aos cuidados peculiares existentes na Unidade de Terapia Intensiva, a monitorização hemodinâmica desses pacientes é realizada por monitores automáticos multiparamétricos o que torna esse procedimento mais fácil e rápido. Esse tipo de monitorização consiste no controle de parâmetros como eletrocardiograma, pressão arterial (direta ou indireta), saturação de oxigênio, frequência cardíaca, temperatura, frequência respiratória, capnografia e débito cardíaco. Para garantir a precisão e o desempenho desses aparelhos automáticos, estes devem passar por testes rigorosos a fim de validá-los para seu uso clinico. Assim torna-se necessário aferir sua confiabilidade usando protocolos adequados, reconhecidos por sociedades cientificas. Este estudo tem como objetivo avaliar a confiabilidade do monitor multiparamétrico Dixtal® DX 2020 na medida da pressão arterial em adultos de acordo com o Protocolo Internacional, proposto pela European Society of Hypertension (ESH). Para o desenvolvimento desse estudo foram realizadas medidas de pressão arterial em 33 sujeitos, com uso do esfigmomanômetro de coluna de mercúrio, da marca Unitec e o aparelho automático Dixtal® DX 2020 com número de série 81303876. Nove medidas sequenciais foram realizadas no braço, alternando entre o esfigmomanômetro de mercúrio e o automático em teste, conforme Protocolo Internacional, além da obtenção do eletrocardiograma. O protocolo estabelece a necessidade de atender duas exigências. Na primeira exigência o aparelho foi reprovado na PAS em todas as faixas. Das 99 diferenças obtidas, apenas 43 se situaram na faixa de 0 a 5 mmHg (de 73 exigidas), 69 medidas na faixa de 0 a 10 mmHg (de 87 exigidas) e 81 entre 0 e 15 mmHg (de 96 exigidas). Na PAD também foi reprovado em todas as faixas, obtendo 29 diferenças entre 0 e 5 mmHg, 56 entre 0 e 10 mmHg e 71 entre 0 e 15 mmHg, sendo exigidas 65, 81 e 93, respectivamente. Na segunda exigência pelo menos 24 sujeitos deveriam ter duas de suas três comparações na faixa de 0 a 5 mmHg, o que aconteceu somente com 16 sujeitos na sistólica e 9 na diastólica. Além disso, no máximo três poderiam ter todas suas comparações acima de 5 mmHg e isso aconteceu com 10 sujeitos na sistólica e 17 na diastólica. O aparelho não atendeu os critérios estabelecidos para a pressão sistólica (PAS) e pressão diastólica (PAD) em nenhuma das duas exigências, não sendo recomendado para o uso clínico de acordo com este protocolo. Cuidados com a validação dos aparelhos deveriam ocorrer com maior frequência no sentido de garantir às pessoas em cuidados intensivos valores fidedignos. É importante ressaltar que este estudo refere-se especificamente ao módulo de verificação da PA do monitor em estudo, não sendo possível tirar a mesma conclusão para suas outras funções / Abstract: The measurement of blood pressure in emergency departments and intensive care is a procedure used to quickly assess the patient's condition and direct the therapeutic approach. Due to the peculiar care existing in the intensive care unit, hemodynamic monitoring of patients is performed by automated multiparameter monitors which makes this procedure easier and faster. This type of monitoring controls parameters such as electrocardiogram, blood pressure (direct or indirect), oxygen saturation, heart rate, temperature, respiratory rate, capnography and cardiac output. To ensure accuracy and performance of these automated devices, they must undergo rigorous testing to validate them for clinical use. So it becomes necessary to assess its reliability using appropriate protocols, recognized by scientific societies. This study aims to evaluate the reliability of the multiparameter monitor Dixtal® DX 2020 on blood pressure determination in adults according to the International Protocol, proposed by the European Society of Hypertension (ESH). For the development of this study blood pressure was measured in 33 subjects, using a Unitec® mercury sphygmomanometer, and the automatic drive Dixtal® DX 2020, serial number 81303876. Nine sequential measurements were performed in the arm, alternating between the mercury sphygmomanometer and the automatic unit in test, as determined by the International Protocol, and the electrocardiogram. The protocol establishes the need to meet two requirements. In the first requirement, the device failed SBP measurements in all ranges. Among the 99 obtained differences, only 43 were located in the range 0-5 mm Hg (73 required), 69 in the range 0-10 mm Hg (87 required) and 81 between 0 and 15 mmHg (96 required). Regarding DBP, the device also failed in all ranges, obtaining 29 differences between 0 and 5 mmHg, 56 from 0 to 10 and 71 between 0 and 15 mmHg( 65, 81 and 93 required respectively). To pass in the second requirement at least 24 subjects should have two of their three comparisons in the range 0-5 mmHg, which happened with only 16 subjects in systolic and 9 in diastolic. Furthermore, at most three could have all their comparisons over 5 mmHg and this happened to 10 subjects in the systolic and 17 diastolic. The unit did not meet the criteria for systolic (SBP) and diastolic blood pressure (DBP) in any of the two requirements and it is not recommended for clinical use in accordance with this protocol. Importantly, this study specifically refers to the BP scanning module of the monitor in study, it is not possible to draw the same conclusion for its other functions / Mestrado / Enfermagem e Trabalho / Mestra em Ciências da Saúde