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Analyse, caractérisation et classification de signaux foetaux / Analysis, characterization and classification of fetal signalsVoicu, Iulian 13 December 2011 (has links)
L’objectif de ce travail est d’obtenir, grâce à un mélange de différentes informations, un monitorage de l’activité du fœtus pour apprécier son état de bien-être ou de souffrance.Actuellement, les paramètres qui caractérisent la souffrance fœtale, issus du rythme cardiaque et des mouvements fœtaux, sont évalués par le médecin et ils sont réunis dans le score de Manning. Deux inconvénients majeurs existent: a) l’évaluation du score est trop longue puisqu’elle dure 1 heure b) il existe des variations inter et intra-opérateur conduisant à différentes interprétations du bilan médical de la patiente.Pour s’affranchir de ces désavantages nous évaluons le bien-être fœtal d’une façon objective, à travers le calcul d’un score. Pour atteindre ce but, nous avons développé une technologie ultrasonore mufti-capteurs permettant de recueillir une soixantaine de signaux Doppler en provenance du cœur, des membres inférieurs et supérieurs. / The objective of this work is to assess the fetal parameters and the fetal well-being using a mixture of fetal parameters. In our days, the parameters derived from heart rate and fetal movements that characterize the fetal distress are assessed by the physician and unified in the score of Manning. Two major disadvantages of Manning’s score exist: a) the assessment of the score is time consuming; b) there are variations inter and intra operators leading to different interpretations of the patients medical record. To overcome these disadvantages we assess the fetal well-being objectively, by computing an automatic/electronic score. To achieve this goal, we developed an ultrasonic multi-sensor unit with 12 sensors allowing to collect sixty Doppler signals from the heart, lower and upper limbs.
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Perceptions and current practices of Namibian midwives regarding the use of the cardio-tocograph as an informative labour monitoring tool for labouring womenUusiku, Laura Ingashipwa January 2017 (has links)
Labour is a vital period for the labouring mothers, as it should bring with it the fulfilment of an expectation of having the baby that has been awaited. The health of the foetus which is to be born and that of the labouring mother are inextricably linked with each other which is why the labouring mother needs to be assessed and monitored carefully. The cardio-tocograph, which is a globally accepted method of diagnosis and assessment of the foetal status during labour is preferred to be used in monitoring labouring mothers, especially high- risk patients. Despite the evidence and information regarding the effectiveness of the use of the cardio-tocograph, midwives are still found not to be using it correctly, the reasons given that the women not always co-operate; do not keep the electrode and belt in place or cite the discomfort they experience from contraction. The objectives of this study were to: explore and describe the perceptions and current practice of Namibian midwives regarding the use of the cardio-tocograph as an informative labour- monitoring tool. Explore and describe how midwives working in labour wards in Namibia perceive informing laboring women of the use of the cardio-tocograph as an informative labour- monitoring tool and based on the results, develop an instruction guide for midwives working in the labour ward in intermediate hospital in Namibia that would serve as a guide on how to teach labouring women about the use of the cardio-tocograph as a labour- monitoring tool and enhance positive labor and delivery outcomes The study was conducted between May and June 2016, using a qualitative, explorative, descriptive and contextual design, following the necessary university approval and approval from other relevant authorities. The research population was midwives who work in labour wards at a public hospital in Namibia. Semi-structured interviews were used to collect data from purposively sampled participants using set criteria. A voice recorder was used to capture the interview with the permission of the participants. Seventeen midwives were interviewed of whom two were used for the pilot study. Data saturation determined the sufficient sample size. The collected data was analyzed using Tesch’s spiral method of data analysis with the assistance of an independent coder From the research findings, it emerged that midwives had varying perceptions regarding the use of the CTG machine. Midwives still perceive CTG interpretation as a challenge as a labour -monitoring tool and expressed a need for updates. Furthermore, midwives expressed the fact that they had limited communication with labouring women regarding the use of CTG. Based on the research findings and guided by Health Belief Model principles, three main guidelines were developed for midwives working in the labour ward in a public hospital in Namibia. These guidelines will serve as a tool to assist midwives in their teaching of labouring women about the use of the cardio-tocograph as a labour- monitoring tool, and the role to be played by labouring women during that monitoring period. Furthermore, recommendations for clinical nursing practice, nursing education and nursing research were developed. The researcher used literature control to ensure validation and integrity of the study. Trustworthiness, which was used to ensure rigour of the study, was guided by the principles of truth-value, transferability, dependability and confirmability. Ethical considerations were guided by the Belmont report adopting the principles of beneficence, respect for human dignity, justice and non-maleficence.
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Analýza fyzické zátěže učitele TV 2. st. ZŠ ve vyučovací jednotce TV a v rámci denního režimu školy / Analysis of the physical burden of physical education teacher at 2nd in elementary school teaching unit of physical education and within the school systemŠMAJCL, Filip January 2018 (has links)
The aim of this thesis is to analyse the physical strain of a PE teacher at the second stage of the primary education during the PE lessons and within the everyday school life. In the theoretical part of the thesis key concepts pedagogy, pedeutology and a brief history of teaching are explained. Furthermore, the profession of a teacher, their duties, personality traits, role and teaching styles are described, as well as the job-analysis of a PE teacher. The most important part is the description and analysis of the physical strain, stress, noise and workload of a PE teacher and the influence of the physical strain on their heart rate. In the practical part of the thesis we deal with eight days of surveying in which we describe in detail the PE lessons. Afterwards we collect the data obtained by using a sport tester within these 30 PE lessons and its parts and we can find out what the energy output of the PE teacher is. From the data obtained according to general physiology we can put the demandingness of the profession of a PE teacher into the corresponding category of work load.
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Avaliação do efeito da administração de piridostigmina sobre a variabilidade da frequência cardíaca em pacientes portadores de diabetes mellitus tipo 2 com neuropatia autonômica cardiovascularHarthmann, Ângela d'Avila January 2010 (has links)
Objetivos/Hipótese: A Piridostigmina bloqueia a acetilcolinesterase, promove estimulação colinérgica e aumenta a variabilidade da freqüência cardíaca (VFC) em indivíduos saudáveis e com insuficiência cardíaca. Os efeitos sobre a modulação autonômica no diabetes mellitus tipo 2 (DM2) são desconhecidos. Nós testamos a hipótese de que a administração de piridostigmina aumenta a VFC em pacientes com DM2 e neuropatia autonômica cardiovascular (NAC). Métodos: Estudamos 34 pacientes com DM2 e NAC com idade entre 30 e 70 anos. Dezessete receberam 30 mg de piridostigmina via oral, de 8/8h por 24h (PI) e 17 receberam placebo (PL). A VFC foi avaliada pela média (RRMed) e desvio padrão dos intervalos RR (SDNN), pela raiz quadrada da média das diferenças sucessivas entre intervalos RR (RMSSD) e pelos índices do Mapa de Retorno Tridimensional P1, P2, P3 e MN. Resultados: Não houve diferenças significativas entre os grupos PI e PL quanto às características clínicas basais e à VFC sob efeito de piridostigmina e PL (RRMed - 748 ± 99 vs 733 ± 111ms; SDNN - 107 ± 26 vs 108 ± 36ms; RRMSD - 20,7 ± 12,7 vs 20,3 ± 10ms; P1 - 63 ± 11 vs 69 ± 14; P2 - 66 ±13 vs 63 ± 15; P3 - 86 ± 34 vs 80 ± 24 e MN - 392 ± 241 vs 369 ± 185). Conclusão: A piridostigmina não modifica a VFC em pacientes com DM2 e NAC. / Aims/Hypothesis: Pyridostigmine blocks acetylcholinesterase, promotes cholinergic stimulation and increases heart rate variability (HRV) in healthy individuals and with cardiac heart failure. The effects on the autonomic modulation in diabetes mellitus type 2 (DM2) are unknown. We have tested the hypothesis that the administration of pyridostigmine increases HRV in DM2 and CAN patients (CAN). Methods: We have studied 34 DM2 and CAN patients aged between 30 and 70 years old. Seventeen received 30mg of pyridostigmine via oral administration, every 8 hours during 24 hours (PY) and 17 received placebo (PL). HRV was assessed by the mean of all normal R-R intervals RR (mean RR) and the standard deviation of all normal R-R intervals (SDNN), by the root-mean-square of successive differences (RMSSD) and by the three-dimensional return map indices P1, P2, P3 and MN. Results: There were no significant differences between the PY and PL groups as to the baseline clinical characteristics and to HRV under the effect of pyridostigmine and PL (mean RR - 748 ± 99 vs 733 ± 111ms; SDNN - 107 ± 26 vs 108 ± 36ms; RRMSD - 20,7 ± 12,7 vs 20,3 ± 10ms; P1 - 63 ± 11 vs 69 ± 14; P2 - 66 ±13 vs 63 ± 15; P3 - 86 ± 34 vs 80 ± 24 e MN - 392 ± 241 vs 369 ± 185). Conclusion: Pyridostigmine does not modify HRV in DM2 and CAN patients.
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Comparação das respostas cardiorrespiratórias, neuromusculares e cinemáticas de um exercício de hidroginástica executado em diferentes cadências com e sem equipamento / Cardiorespiratory, neuromuscular and kinematic responses to a water exercise performed at different cadences with and without equipmentPinto, Stephanie Santana January 2009 (has links)
O objetivo do presente estudo foi comparar as respostas cardiorrespiratórias, neuromusculares e cinemáticas durante o exercício de corrida estacionária com a flexão e extensão de cotovelo em diferentes cadências com e sem equipamento. A amostra desse estudo foi composta por 15 mulheres jovens que realizaram o exercício nas situações sem equipamento (SEM), com equipamento flutuante em ambos os membros (FLU-MSs/MIs) e com equipamento resistivo em ambos os membros (RES-MSs/MIs), nas cadências de 80 bpm, 100 bpm e no máximo esforço. Para as cadências submáximas o exercício foi realizado durante 4 min em cada situação e no máximo esforço o mesmo foi realizado durante 15 s. Utilizou-se ANOVA de 2 e 3 fatores, com post-hoc de Bonferroni (p < 0,05) (SPSS vs 15.0). Os resultados da frequência cardíaca e do consumo de oxigênio mostraram haver diferenças significativas entre as situações FLUMSs/ MIs e RES-MSs/MIs em comparação a SEM, com valores significativamente maiores para as situações de exercício com equipamento. Além disso, houve diferença entre as cadências de 80 e 100 bpm, com valores maiores e significativos para a cadência de 100 bpm. Para as variáveis de amplitude de movimento houve diferenças entre as cadências, com valores maiores de amplitude de movimento do quadril e joelho, conforme o incremento da cadência. Todavia, para a amplitude de movimento do cotovelo com o incremento da cadência houve uma diminuição da amplitude de movimento. Em relação a velocidade angular média de movimento do cotovelo, quadril e joelho houve diferenças significativas entre as cadências, com valores maiores para o máximo esforço. A velocidade angular média do quadril foi menor nas situações FLUMSs/ MIs e RES-MSs/MIs em comparação a SEM. Para as variáveis neuromusculares, não houve diferenças entre as situações, com exceção do percentual da contração isométrica voluntária máxima (%CVM) do tríceps braquial, que foi maior na situação FLU-MSs/MIs. Entre as diferentes cadências submáximas não houve diferenças para todos os músculos analisados, todavia entre essas e o máximo esforço houve diferenças, com maiores %CVM para o máximo esforço. O %CVM do bíceps femoral foi o único que demonstrou diferenças entre todas as cadências testadas nesse estudo. Entre as fases de movimento não houve diferença, com exceção do %CVM do reto femoral, o qual foi maior na fase de extensão. Em suma, o exercício de corrida estacionária com a flexão e extensão de cotovelo apresentou maiores respostas cardiorrespiratórias com o uso de equipamento (flutuante e resistivo) e também com o aumento da cadência de execução. Todavia, as respostas neuromusculares não diferiram entre as cadências submáximas, mas essas foram significativamente maiores no máximo esforço. / The purpose of the present study was to compare the cardiorespiratory, neuromuscular and kinematic responses during the stationary running with the elbow flexion/extension in different cadences with and without equipment. The sample was consisted of fifteen young women that performed the exercise without equipment (NO-E), with floating equipment in upper and lower limbs (FLO-LLs/ULs) and with resistive equipment in upper and lower limbs (RES-LLs/ULs) at three cadences (80 bpm, 100 bpm and maximal effort). For submaximal cadences the exercise was performed during 4 min and during 15 s at maximal effort in each situation. The results were analyzed using repeated measures ANOVA (factors: cadence, situation, phase of movement) with the Bonferroni correction for post-hoc comparisons (p < 0,05) (SPSS vs 15.0). The heart rate and oxygen uptake showed significant differences between FLO-LLs/ULs and RES-LLs/ULs compared with NO-E and higher values of these variables was found in the situations with equipment. In addition, the results for cardirespiratory responses demonstrated significant difference between submaximal cadences (80 and 100 bpm) with higher values of heart rate and oxygen uptake at 100 bpm. For the range of motion significant differences between cadences was showed with higher values of this variable for hip and knee according to the increment of the cadence. However, the range of motion for elbow decreased with the increment of the cadence. The angular velocity for elbow, hip and knee presented significant differences between cadences with higher values at maximal effort. Besides, the angular velocity for hip was minor in the situations FLU-LLs/Uls and RES-LLs/ULs compared with NO-E. For neuromucular responses no significant differences were showed between situations, except the percentage of maximal voluntary contraction (%MVC) for triceps brachii that was major in FLO-LLs/ULs. Between the different submaximal cadences no significant differences was found for all muscles analyzed, however, between these submaximal cadences and maximal effort were found significant differences with higher values of the %MVC at maximal effort. The unique %MVC that demonstrated significant differences between all cadences analyzed in this study was for biceps femoris. Between the phases of movement (flexion and extension) no significant difference was showed for all muscles investigated, except for the %MVC for rectus femoris that was higher in extension phase. In conclusion, the stationary running with the elbow flexion/extension presented higher cardiorespiratory responses with equipment (floating and resistive) and also with the enhance at the cadence of execution. Nevertheless, neuromuscular responses showed no significant difference between submaximal cadences, but these responses were significantly higher at maximal effort.
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Analýza zatížení hráče v utkání národní házené / Analysis of player's load in national handball matchHokr, Jaromír January 2018 (has links)
Title: Analysis of player's load in national handball match Aim: The aim of the work was to measure the internal and external load of the national handball players during the second league match and then to analyze the data. Methodology: 7 players from TJ Šroubárna Žatec took part in the measurement, including 1 defender, 3 midfielder and 3 strikers. Prior to the load measurement, the maximum heart rate was determined for each player using the Yo - Yo Intermittent Load Test by using the Polar Team 2 Sporttesters. The load measurement took place in a second - league match between TJ Šroubárna Žatec and TJ Spartak Rožmitál pod Třemíšnem. The measured data was processed in MS Excel. The level of statistical significance was set at p <0.05. Results: The results show that the longest distance players have traveled in the zones of staying (49.2% distance), walking (26.5% distance) and running (15.4% distance). They spent the longest time in the zones of the staying (54.5% of the time), walking (21.6% of the time) and the troting (19.5% of the time) and their heart rate was mostly in the zones 80-90% SFmax (28.2% time), 70-80% SFmax (23.1% of time) and below 60% SFmax (18.5% of time). The average speed of the players was 2.3 km / h and the average heart rate was 146 beats per minute. The average distance...
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Where the Heart Meets the Mind’s Eye: Associations Between Cardiac Measures of Autonomic Activity and Selective Attention in Children and AdultsGiuliano, Ryan 06 September 2017 (has links)
Multiple theoretical frameworks posit that interactions between the autonomic nervous system and higher-order neural networks are crucial for cognitive regulation. However, few studies have directly examined whether autonomic physiology influences brain activity during cognitive tasks, and even fewer of those studies have examined both autonomic branches when doing so. Measures of selective attention derived from event-related brain potentials (ERPs) are particularly well-suited for addressing this question, given that ERP selective attention tasks are designed to control for the influences of psychomotor processes and arousal and are predictive of higher-order cognitive function in children and adults. Such research is particularly promising for understanding how early adversity impacts neurocognitive development in children, given that stress experienced early in life impacts both autonomic function and selective attention.
Here, a broad literature review is presented, integrating findings across studies of autonomic physiology, cognition, and brain activity in children and adults (Chapter 1). Then, two experiments are described where cardiac measures of parasympathetic and sympathetic activity were recorded concurrently with ERPs during an auditory selective task in a sample of adults (Chapter 2) and in a sample of preschool-aged children (Chapter 3). Results from both experiments demonstrate a key role for the sympathetic nervous system in selective attention for adults and children, such that greater sympathetic activity is associated with larger effects of selective attention on ERPs. These findings are then reviewed with suggestions for how existing models of neurovisceral integration might be updated to better emphasize the role of sympathetic nervous system activity in neurocognitive processes, emphasizing measures of threat-related and reward-related arousal, as represented by galvanic skin response and pre-ejection period, respectively (Chapter 4). Future directions are also discussed, including recommendations for future studies of neurovisceral integration to examine associations between physiology, behavior, and brain activity at the single-trial level, to incorporate participants from more diverse backgrounds of life experience, and to examine the plasticity of autonomic mechanisms implicated in neurocognitive function.
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A Machine Learning Method to Improve Non-Contact Heart Rate Monitoring Using RGB CameraGhanadian, Hamideh 12 December 2018 (has links)
Recording and monitoring vital signs is an essential aspect of home-based healthcare. Using contact sensors to record physiological signals can cause discomfort to patients, especially after prolonged use. Hence, remote physiological measurement approaches have attracted considerable attention as they do not require physical contact with the patient’s skin. Several studies proposed techniques to measure Heart Rate (HR) and Heart Rate Variability (HRV) by detecting the Blood Volume Pulse (BVP) from human facial video recordings while the subject is in a resting condition. In this thesis, we focus on the measurement of HR.
We adopt an algorithm that uses the Independent Component Analysis (ICA) to separate the source (physiological) signal from noise in the RGB channels of a facial video. We generalize existing methods to support subject movement during video recording. When a subject is moving, the face may be turned away from the camera. We utilize multiple cameras to enable the algorithm to monitor the vital sign continuously, even if the subject leaves the frame or turns away from a subset of the system’s cameras. Furthermore, we improve the accuracy of existing methods by implementing a light equalization scheme to reduce the effect of shadows and unequal facial light on the HR estimation, a machine learning method to select the most accurate channel outputted by the ICA module, and a regression technique to adjust the initial HR estimate. We systematically test our method on eleven subjects using four cameras. The proposed method decreases the RMSE by 27% compared to the state of the art in the rest condition. When the subject is in motion, the proposed method achieves a RMSE of 1.12 bpm using a single camera and RMSE of 0.96 bpm using multiple camera.
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Efeito do bloqueio dos receptores opioides MU, KAPPA e DELTA centrais sobre a hipotensão induzida pela ativação dos receptores serotoninérgicos 5-HT3 centraisOliveira, Elenilda Farias de January 2010 (has links)
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Previous issue date: 2010 / Universidade Federal da Bahia. Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz / Estudos mostram a participação das vias serotoninérgicas e opiatérgicas centrais no controle da pressão sanguínea. A existência de interação entre vias serotoninérgicas e opiatérgicas centrais tem sido demonstrada por diferentes autores. Objetivo: O presente trabalho foi desenvolvido para investigar a participação dos receptores do tipo k e ô opiatérgicos centrais na resposta hipotensora induzida por ativação serotoninérgica e o papel do sistema nervoso simpático. Material e Métodos: Foram utilizados ratos Wistar (280 a 320g) submetidos a cirurgia de estereotaxia com canulação do ventrículo lateral. Um dia antes da sessão experimental, os animais foram submetidos à cateterização da artéria carótida para registro da pressão sanguínea e da veia jugular para infusão de drogas. A pressão sanguínea e frequência cardíaca foram registradas continuamente por 120 min após a injeção das drogas (Sistema de Aquisição de Dados - AqDados) e expressas como delta da pressão arterial média (PAM) e da frequência cardíaca (FC) em relação aos valores pré-injeção. Resultados: A administração de m-CPBG, agonista serotoninérgico S-HTs (160 nmol) em animais pré-tratados com salina causou redução significante da pressão sanguínea. A administração de ondansetrona, antagonista serotoninérgico 5-HT3 (80 nmol) promoveu aumento significante da pressão sanguínea. O pré-tratamento com ondansetrona bloqueou a resposta hipotensora decorrente da ativação dos receptores serotoninérgicos 5-HT3. O pré-tratamento com os antagonistas opiatérgicos naloxona, (30 nmol) e nor-binaltorfimina (10 nmol) bloqueou resposta hipotensora decorrente da ativação dos receptores 5-HT3, enquanto o pré-tratamento com o antagonista naltrindole (1 imiol) promoveu resposta hipertensora. A administração dos antagonistas isoladamente não promoveu alterações significativas da pressão sanguínea e fi’equéncia cardíaca. O bloqueio simpático periférico com prazosin (3mg/mL), antagonista ai- adrenérgico, impediu bloqueio à hipotensão promovido pelo antagonista nor- binaltorfimina, e reduziu parciahnente o bloqueio promovido pelos antagonistas naloxona e naltrindole. Conclusões principais: Os dados sugerem que a resposta hipotensora decorrente da ativação farmacológica dos receptores 5-HT3 centrais é dependente da integridade funcional dos receptores opioides tipo [x, k e 5 localizados no sistema nervoso central e é justificada por um mecanismo de inibição da atividade simpática. / Central serotonergic and opiatergic pathways participate in the mechanisms regulating blood pressure. Furthermore, interaction between serotonergic and opiatergic circuits at the central nervous system has been demonstrated. In the present study, we investigated the role of central k and 8 opioid receptors in the hypotensive response obtained after pharmacological activation of central 5-HT3 receptors, as well as the role of the sympathetic nervous system in this response. Wistar male rats (280-320 g) had the right lateral ventricle cannulated 5 days before the experimental sessions; polyethylene catheters were inserted into the left carotid artery (for blood pressure monitoring) and into the right jugular vein (for drug administration) 24h before the experiments. Blood pressure and heart rate were monitored for the next 2 hours after the administration of the drugs (Data Aquisition System by AqDados). Data were expressed as delta mean arterial pressure (MAP) and heart rate (HR). The MAP value at the end of the stabihzation period was considered the reference blood pressure at time zero and delta values are presented throughout the experiments. The central administration of m-CPBG, a selective 5-HT3 receptor agonist (160 nmol) induced a significant decrease in MAP in control (saline-pretreated) animals. Conversely, the central administration of ondansetron, a selective 5-HT3 receptor antagonist (80 nmol), evoked a significant increase in MAP. Pretreatment with ondansetron abolished the hypotensive response obtained after the stimulation of central 5-HT3 receptors by m- CPBG. Pretreatment with naloxone (30 imiol), a non-selective opiod antagonist, and with nor-binaltorfimine (NOR-BNI), a selective K-opioid receptor antagonist, blocked the hypotensive response observed after central 5-HT3 receptor stimulation. On the other hand, pretreatment with naltrindole (1 nmol), a selective 5-opioid antagonist, blocked the hypotensive response generated by central 5-HT3 receptor stimulation and promoted, after 15 minutes, a significant hypertensive response. The administration of each one of the opioid antagonists alone was unable to promote any significant change in MAP and HR, The blockade of sympathetic function by the peripheral administration of prazosin (al receptor blocker) abolished the blockade of the hypotensive response observed after 5-HT3 receptor stimulation induced by the K-opioid receptor antagonist NOR-BNI and blunted the blockade of the hypotensive response previously seen in animals treated with m-CPBG and pretreated with the opioid antagonists naloxone and naltrindole. The data presented here suggest that the hypotensive response obtained after the central stimulation of 5-HT3 receptors depends on the fiinctional integrity of central K and Ô opioid receptors and relies on a sympathoinhibitory mechanism.
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Estudo e aplicação de diferentes métodos para redução de falsos alarmes no monitoramento de frequência cardíacaBorges, Gabriel de Morais January 2015 (has links)
O monitoramento automático de pacientes é um recurso essencial em hospitais para o bom gerenciamento de cuidados médicos. Enquanto que alarmes devido a condições fisiológicas anormais são importantes para o rápido tratamento, estes também podem ser uma fonte de ruídos desnecessários devido a falsos alarmes causados por interferência eletromagnética ou movimentação de sensores. Uma fonte significativa de falsos alarmes é relacionada com a frequência cardíaca, o qual é disparado quando o ritmo cardíaco do paciente está muito rápido ou muito lento. Neste trabalho, a fusão de diferentes sensores fisiológicos é explorada para fazer uma estimativa robusta de frequência cardíaca. Um conjunto de algoritmos utilizando índice de variabilidade cardíaca, inferência bayesiana, redes neurais, lógica fuzzy e votador majoritário são propostos para fundir a informação do eletrocardiograma, pressão sanguínea e fotopletismograma. Três informações básicas são extraídas de cada sensor: variabilidade cardíaca, a diferença de frequência cardíaca entre os sensores e a análise espectral. Estas informações são usadas como entradas para os algoritmos. Quarenta gravações selecionadas do banco de dados MIMIC são usadas para validar o sistema. Finalmente, a frequência cardíaca calculada é comparada com as anotações do banco de dados. Resultados mostram que a fusão utilizando redes neurais apresenta a melhor redução de falsos alarmes de 89.33%, enquanto que a técnica bayesiana apresenta uma redução de 83.76%. A lógica fuzzy mostrou uma redução de 77.96%, o votador majoritário 61.25% e o índice de variabilidade cardíaca de 65.43%. Portanto, os algoritmos propostos mostraram bom desempenho e podem ser muito úteis em monitores de sinais vitais modernos. / Automatic patient monitoring is an essential resource in hospitals for good health care management. While alarms due to abnormal physiological conditions are important to deliver fast treatment, it can be also a source of unnecessary noise due to false alarms caused by electromagnetic interference or motion artifacts. One significant source of false alarms are those related to heart rate, which is triggered when the heart rhythm of the patient is too fast or too slow. In this work, the fusion of different physiological sensors is explored in order to create a robust heart rate estimation. A set of algorithms using heart rate variability index, bayesian inference, neural networks, fuzzy logic and majority voting is proposed to fuse information from electrocardiogram, arterial blood pressure and photoplethysmogram. Three basic informations are extracted from each source, namely, heart rate variability, the heart rate difference between sensors and the spectral analysis. These informations are used as inputs to the algorithms. Forty selected recordings from MIMIC database was used to validate the system. Finally, the calculated heart rate is compared with the database annotation. Results show that neural networks fusion presents the best false alarms reduction of 89.33%, while the bayesian technique presents an error reduction of 83.76%. Fuzzy logic showed an error reduction of 77.96%, majority voting 61.25% and the heart rate variability index 65.43%. Therefore, the proposed algorithms showed good performance and can be very useful for modern bedside monitors.
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