The prevalence and use of medical devices in the home environment continues to grow in the United Kingdom (UK) and Worldwide. It is recognised that such devices offer significant benefits to both patients and the National Health Service in the UK. The design of home use medical devices however represents a considerable challenge to designers and manufacturers alike. Developing devices that are usable and understandable by inexperienced, lay or dexterity impaired users requires an understanding across a breadth of disciplines. Previous research in this field has explored these challenges in attempt to offer support for developers of home use medical devices. There have been very few studies however that have explored whether the design community actually need, want or use such guidance, before considering whether this literature is adopted correctly. Through case studies, an online survey and in depth interviews this thesis suggests that industry practitioners are sceptical of the value of design guidance towards user involvement in home use medical device design. Consequently the practitioners in this research make little or no use of the formal design methods and supportive guidance documents available to them. More typically, practitioners in the home use medical device field use their own personal experiences and knowledge from working in the industry to adapt their own approaches to design. This thesis reports that the greatest challenge to involving users in the design of home use medical devices are the internal corporate and traditionally hierarchical barriers between stakeholders within the design process. In contrast to previous research offering support for designers and developers of home use medical devices this thesis calls for a wider change in design practice to facilitate the application of usability principles. As a conclusion to this thesis, recommendations for further research to address these changes in practice are proposed to industry professionals in the medical device industry. This thesis is submitted as part of the requirement for the Degree of Doctor of Philosophy at Loughborough University.

An emerging trend of the healthcare industry is the huge increase in the number of medical devices being used by lay people at home. Home use medical devices range from simple inhalers to very complicated devices such as defibrillators. This research aimed to assist designers in developing home use medical devices by providing information and suggestions regarding lay users and how to address their needs and expectations. For this purpose a qualitative and inductive approach was adopted and several studies were carried out, including: (1) a comprehensive literature review to understand the background of the phenomena; (2) observational studies with 40 lay users (i.e. 10 younger lay users, 10 older lay users, 10 users with mobility and sensory disabilities, and 10 users with cognitive disabilities) in order to identify their characteristics when interacting with products; (3) an online questionnaire survey with 53 designers to understand designers‟ requirements when designing home use medical devices, as well as their expectations for a proposed design support tool; (4) the development of the design support tool; and (5) an evaluation study with 12 professional designers in order to assess the effectiveness of the tool (in a format of a design guidance). This research adopted an inclusive approach which investigated both lay users‟ characteristics and designers‟ perspectives. It has, for the first time, outlined lay user characteristics based on empirical studies with different groups of people. It is also one of few studies focussing on designing home use medical devices; the requirements of professional designers have provided an in-depth insight into the challenges of designing medical devices for use in the home environment. The design guidance, as commended by the designers in the evaluation, was the first comprehensive information source in the UK for the emerging home use medical device field where little support is currently available.

La perfusion intraveineuse occupe une large place dans les services de soins cliniques. Les patients reçoivent de nombreux médicaments simultanément dans la même voie centrale, où des problèmes de compatibilité entre les médicaments peuvent survenir. La maitrise de ces incompatibilités médicamenteuses, génératrices de particules, représente donc un enjeu majeur dans la prise en charge des patients polymédiqués.La première partie de ce travail est une analyse de la littérature portant sur les incompatibilités médicamenteuses et leurs principales conséquences sur le plan clinique. A ce titre, un chapitre est dédié à l’ensemble des moyens de prévention de ces problèmes, parmi lesquels l’usage de filtres en ligne de perfusion ou de dispositifs de perfusion multi-lumières.La première partie de nos travaux expérimentaux est consacrée à l’évaluation de la filtration terminale comme stratégie de prévention de l’administration de particules aux patients. Dans ce contexte, nos travaux ont porté sur le noircissement des filtres en ligne observé dans un service de réanimation néonatale. L’objectif était de définir la nature de l’incompatibilité en cause et de s’assurer, dans un second temps, de l’efficacité des filtres malgré les phénomènes de noircissement. Les filtres ont été examinés par microscopie électronique et comptage particulaire. Un aminogramme de la nutrition parentérale a également été réalisé. Une interaction spécifique a été mise en évidence entre un acide aminé (la cystéine) et un oligoélément (le cuivre) dans les poches. De plus, le maintien de la fonction des filtres en ligne a été démontré.La seconde partie de nos travaux est axée sur l’évaluation de l’intérêt d’un dispositif médical multi-lumières innovant dans la prévention des incompatibilités médicamenteuses. Le premier travail mené dans cette thématique a montré in vitro son intérêt à prévenir la survenue d’incompatibilités physiques entre plusieurs associations médicamenteuses, allant de deux à six médicaments administrés simultanément. Nos résultats indiquent que la conception de ces nouveaux dispositifs de perfusion et notamment leur géométrie interne permet de minimiser le temps de contact entre les produits, et ainsi d’améliorer la compatibilité entre les produits, au même titre que le type de solution d’hydratation. Le second travail consistait à poursuivre l’évaluation de ces dispositifs de perfusion multi-lumières en reproduisant un protocole de perfusion utilisé habituellement en hématologie pédiatrique et associant plusieurs médicaments incompatibles à l’origine de précipité. Un comptage particulaire réalisé de manière dynamique a permis de montrer que l’emploi de ces dispositifs permettait de réduire significativement la charge particulaire administrée aux patients, en comparaison avec les dispositifs standard de perfusion (rampes de robinets).Les résultats de l’ensemble de nos travaux sont prometteurs pour l’amélioration de la prise en charge des patients. Ils doivent être maintenant confirmés au travers d’une étude clinique. / Intravenous infusions are extensively used in clinical wards. Patients simultaneously receive many drugs through a limited number of venous accesses, thus increasing the risk of physical drug incompatibilities. Preventing incompatibility is therefore important for the safe administration of injectable drugs of polymedicated patients.The first part of this work consisted in analysing published literature on drug incompatibilities and their clinical consequences. This chapter includes a review of tools preventing drug incompatibilities, which include in-line filtration or the use of multi-lumen infusion sets.The first part of our experimental work is dedicated to the evaluation of terminal in-line filtration for preventing the injection of drug particles to patients. In this context, our research has focused on the blackening of in-line filters, which have been observed during the infusion of binary parenteral nutrition (BPN) delivered in a neonatal intensive care unit. The purposes of our study were, first, to examine the elemental content of precipitates isolated from infused BPN bags and so determine the main physicochemical interactions occurring in them and, second, to evaluate the blackening effect of in-line filters on filtration capacity. Filter membranes were examined by scanning electron microscopy and energy dispersion spectroscopy. Amino acid (AA) profiles were obtained from BPN mixtures to determine the concentrations of each AA. A specific interaction was identify between cysteine and copper in our BPN. Despite the gradual blackening of in-line filters during BPN bag infusion, the filter membranes continued to filter solutions efficiently and safely.The second part of our work focused on the assessment of the impact of new multilumen infusion access devices on the occurrence of known drug incompatibility.The first study used a well-documented incompatible combination of two to six drugs and three different carrier fluids. The multilumen infusion access device was able to prevent the occurrence of drug incompatibilities in nearly half of the drug combinations tested. This study confirmed that the characteristics of an infusion device have an impact on drug physical incompatibilities. The main hypothesis is those fluid dynamics differ according to infusion device and accesses, which modify the contact time between drugs and the infusion vehicle.The second in vitro study focused on a pediatric multidrug protocol for patients diagnosed with lymphoblastic leukemia and receiving allogeneic transplantation. A dynamic particle count test was used over 24 hours to evaluate the overall particulate contamination. The use of a multi-lumen infusion set reduces significantly overall particulate contamination compared to the standard infusion set.These results pave the way to performing a randomized controlled clinical trial assessing the multilumen infusion access device.

Ce travail de doctorat s’inscrit dans un projet de recherche destiné à évaluer la charge particulaire issue des incompatibilités physico-chimiques d’origine médicamenteuse de patients admis en réanimation pour un état de choc septique ou un syndrome de détresse respiratoire aigüe. Le corollaire est de faire le lien avec la survenue de certaines complications (syndrome inflammatoire et dysfonction d’organe) susceptibles de menacer le pronostic vital. En effet, la dysfonction microcirculatoire caractéristique de ces patients pourrait être majorée par la contamination particulaire aboutissant ainsi à une aggravation de l’hypo-perfusion tissulaire et à la survenue du syndrome de défaillance multi viscérale.La première partie de ce travail a consisté en une analyse de la littérature portant sur les incompatibilités médicamenteuses et leurs principales conséquences cliniques sous forme d’une revue systématique. Un des messages essentiels est l’intérêt grandissant de la filtration en ligne comme moyen de prévention de la contamination particulaire bien mis en évidence par certains essais contrôlés randomisés en particulier pédiatriques.La seconde partie de ce travail était de mener, dans une première phase, une étude d’observation clinique au lit du malade des dispositifs de perfusion intraveineux habituellement utilisés et des médicaments le plus souvent administrés à ces patients de réanimation du CHU de Lille. La deuxième phase consistait à reproduire in vitro le montage de perfusion utilisé en clinique avec les différentes solutions médicamenteuses dans le but de quantifier la charge particulaire à laquelle sont exposés les patients. Le comptage particulaire a été réalisé de manière dynamique, selon une technique innovante, grâce à un analyseur de particule connecté au montage de perfusion.Ce travail nous a permis finalement d’évaluer le risque particulaire pour ces patients fragiles et de proposer une stratégie de prévention des incompatibilités médicamenteuses. / Our PhD work aimed to evaluate the particulate exposure induced by drug incompatibilities in patients admitted in ICU for a septic shock or acute respiratory distress syndrome. The purpose was to establish a link with the occurrence of certain complications (inflammatory syndrome and organ dysfunctions) susceptible to aggravate life threatening. Indeed, the microcirculatory dysfunction characteristic of these patients could be increased by the particulate contamination, compromising tissue perfusion and leading to the occurrence of multi organ failureThe first part of this study consisted in a systematic literature review on the clinical implications of drug incompatibilities. One of the essential messages is the growing interest of inline filtration to prevent particulate contamination, highlighted by randomized controlled trials especially in pediatric ICU.The second part of the study was to conduct, in a first phase, an observational study, at the ICU patients’ bedsides, of the commonly used intravenous drugs and infusion sets. The second phase was to reproduce in vitro the previous observed infusion lines using the observed drugs combination, in order to quantify the particulate exposure, during a simulated 6-hour infusion period. The particle counting was performed using an innovative dynamic image analysis device.Our work indicates the amount of particulate matter potentially administered to critically-ill adult patients and paves the way to a strategy of prevention of drug incompatibilities.

No contexto da especificidade da urbanização brasileira, onde as cidades crescem simultaneamente às formas de trabalho com capitais reduzidos e tecnologias menos modernas, nossa pesquisa analisa o território usado por diferentes agentes do sistema produtivo de equipamentos médicohospitalares no Estado de São Paulo, atentando para as diferentes divisões do trabalho existentes na forma dos circuitos da economia urbana. Valorizado de forma seletiva, o meio construído permite que atividades mais e menos rentáveis se instalem, enquanto a coexistência de divisões do trabalho que datam de diferentes épocas assegura uma dinâmica interdependente entre os circuitos da economia urbana. Neste sentido, discutimos a existência de um circuito superior marginal ligado às atividades de produção de equipamentos médicohospitalares em Campinas, Ribeirão Preto e São José do Rio Preto (SP) e o papel complementar que este cumpre para os serviços de saúde do país. / In the context of the specificity of Brazilian urbanization, where simultaneous with the growth of the cities, the types of work with reduced capital and less modern technologies also grow, our research analyses the territory used by different agents of the medicalhospital equipments production system in the state of São Paulo, looking at the different divisions of labor, existing in ways of the circuits of urban economy. Valued in a selective way, the environment building allows installation of more or less profitable activities, while the coexistence of divisions of labor of different ages ensures an interdependent dynamic among the circuits of the urban economy. In this way, we discuss the existence of a marginal upper circuit related to the medicalhospital equipments production in Campinas, Ribeirão Preto e São José do Rio Preto (SP) and its complementary function that it accomplishes for the brazilian health services.

O objetivo geral do estudo proposto é analisar a terminologia presente em manuais de empresas fabricantes de equipamentos médicos utilizados nas Unidades de Terapia Intensiva UTIs, cujo tema foi definido em parceria com os especialistas do Grupo de Engenharia Biomédica da UNIFEI. Primeiramente, levantamos a lista dos equipamentos médicos utilizados em UTIs, com o auxílio dos especialistas, e formamos um corpus de estudo. Verificamos a existência de possíveis variantes denominativas no corpus constituído e, posteriormente, analisamos as relações semânticas estabelecidas entre os termos validados. A identificação e a extração dos termos presentes nos manuais foram realizadas por meio da plataforma Terminus, desenvolvida pelo Grupo IULATERM, do Institut Universitari de Lingüística Aplicada da Universitat Pompeu Fabra. A partir dos dados coletados, pudemos verificar a existência de muitas variantes e propusemos uma análise das relações semânticas existentes entre eles. Para esta pesquisa, adotamos a perspectiva teórica veiculada pela Teoria Comunicativa da Terminologia TCT, que considera que as unidades terminológicas são parte da língua geral e apresentam as mesmas características desta, comportando variações denominativas e outros fenômenos. / The overall goal of the proposed study is to analyze the terminology used in manuals of manufacturers of medical equipment used in Intensive Care Units ICUs, theme established in partnership with UNIFEI´s Group of Experts on Biomedical Engineering. First, with the support from experts, a list of medical devices used in ICUs was raised and a study corpus generated. We searched possible denominational variants in the constituted corpus and then analyzed the semantic relations between the validated terms. The identification and extraction of these terms from the manuals were made by the Terminus platform developed by IULATERM Group, Institute for Applied Linguistics at Universitat Pompeu Fabra. From the data collected, we could confirm the existence of many variants and, therefore, propose an analysis of the semantic relationships among them. For this research, we adopted the theoretical perspective conveyed by the Communicative Theory of Terminology, which considers that the terminological units are part of the general language and have the same characteristics, comprising denominational variations and other phenomena.

<p>Implantable biomedical devices have been widely used to treat a variety of diseases for many decades. If allowed by the size and form factor, batteries have been the power source of choice in implantable devices (e.g., cardiac pacemakers). Batteries are, however, still big and come in shapes that are not ideal for minimally invasive deployment. Inductive powering is another commonly used energy source in which two well-aligned coils allow a transmitter to power the implanted receiver (e.g., cochlear implants). Once the receiver coil becomes small (mm-scale), the inductive powering link becomes very inefficient and sensitive to slight misalignment between the coils. Hence, it becomes increasingly difficult to power small devices implanted deep (>5 cm) within the tissue using inductive powering. Ultrasonic powering is an attractive alternative for powering miniature devices since it can penetrate deep into the tissue, it has greater efficiency at mm-scale receiver size, it can be omni-directional, and it is more amenable to miniaturization.</p> <p>In this dissertation, I describe the use of ultrasonic waves to power and control mm-scale implantable devices. After a detailed look at ultrasonic transmission link, I will discuss factors affecting the power transfer efficiency. These include the effect of receiver aspect ratio and size on the resonant frequency and factors related to acoustic and electrical matching. A 3D printed acoustic matching layer in then described. I will discuss two applications using ultrasound to power and control implantable devices. The first is a low-power on-off acoustic control scheme to reduce the standby power consumption in implantable devices. The second is an ultrasonically powered electrolytic ablator with an on-board micro-light-source for the treatment of cancer.</p>

Dentro das exigências restritivas visando à mitigação de danos ambientais, várias ações estão sendo tomadas em termos mundiais, destacando-se os países onde a mobilização social e tomadas de decisão são mais efetivas. Entre estas ações as diretivas RoHS e WEEE, ambas da comunidade européia, destacam-se como interessantes procedimentos que se somam para a prevenção do uso de substâncias tóxicas e redução de emissão ao meio ambiente de resíduos sólidos de eletrônicos após o uso. Atualmente, em termos mundiais, não se observa o uso de tais procedimentos no que tange aos equipamentos eletromédicos após o término de vida útil e descarte. Este trabalho faz um estudo de ambas diretivas utilizando-se um equipamento eletromédico de fabricação nacional, um eletroestimulador. O equipamento foi criteriosamente desmontado e seus componentes classificados com base em sua classe de material e composição química. Após a desmontar e catalogar os componentes quanto à classe de materiais e composição química, foram sugeridos alguns procedimentos. Para atender a diretiva RoHS, a substituição de metais pesados presentes na liga utilizada na soldagem dos componentes eletrônicos. Para atender a diretiva WEEE, o processamento de resíduo de placa de circuito impresso inertizado em vidro. Deste modo verifica-se que os procedimentos adotados para cumprir com as duas diretivas européias foram adequados para os equipamentos eletromédicos tanto de fabricação nacional como internacional. / Within the restrictive requirements aimed at mitigating environmental damage, several actions being taken globally, highlighting the countries where social mobilization and decision making are more effective. Among these actions the RoHS and WEEE, of the European community, stand out as interesting procedures that are in addition to preventing the use of toxic chemicals and reducing emissions to the environment of electronic waste after use. Today, in the world is unusually such procedures with respect to electrical equipment after the end of useful life and its disposal. This work is a study of both using an electromedical equipment manufactured in Brazil, an electrostimutator. The equipment was carefully dismantled and its components classified based on their specific device and chemical composition. After removing and cataloging the components of the different kind of materials and chemical composition, suggested some procedures. To meet the RoHS directive, the replacement of nocive metals in the alloy used in soldering of electronic components. To meet the WEEE directive, the processing of waste printed circuit board inerted glass. Thus it appears that the procedures adopted to comply with two European directives were adequate for the electrical equipment manufacturing both domestically and internationally.

Rapid determination of drugs effective against bacterial strains is critically important to stopping further spread of an infection and reducing antibiotic resistance. Antimicrobial susceptibility testing (AST) is done to determine what type of antibiotic and what concentration will be effective in treating an infection. Current, growth-dependent, AST methods are reliant on the growth rate of the bacteria and can take several days to several weeks to get results. A piezoelectric plate sensor can be used to measure an instant change in the minute physiological stresses of the bacteria cells when they are exposed to an effective concentration of antibiotic. This work aims to investigate the feasibility of piezoelectric plate sensors used for instantaneous AST (iAST) results and develop a technological framework for scaling this technology to a clinical lab setting. Four Clinical and Laboratory Standards Institute (CLSI) quality control strains of bacteria were tested with a wide range of antibiotics from various drug classes using the piezoelectric sensor. Results were obtained within 30 minutes and compared to standard of care AST methods used in clinical labs, and CLSI prescribed ranges for each strain of bacteria. This thesis will also discuss a framework for developing more scalable sensors, and challenges associated with the different sensor designs.

The breath figure method is a versatile and facile approach of generating ordered micro and nanoporous structures in polymeric materials. When a polymer solution (dissolved in a high vapor pressure organic solvent) is evaporated out in the presence of a moist air stream, the evaporative cooling effect causes the condensation and nucleation of water droplets onto the polymer solution surface. This leads to the formation of an imprinted porous structure upon removal of the residual solvent and water. The facile removal of the water droplet template leaving its structural imprint is a specifically appealing aspect of the breath figure film technology. The first part of the dissertation work involves the fabrication of drug loaded breath figure thin films and its utilization as a controlled drug release carrier and biomaterial scaffold. In a single fabrication step, single layer/multilayer porous thin films were designed and developed by combining the breath figure process and a modified spin or dip coating technique. Using biodegradable polymers such as poly (lactic-co-glycolic acid) (PLGA) and poly (ethylene glycol) (PEG), drug loaded films were fabricated onto FDA approved medical devices (the Glaucoma drainage device and the Surgical hernia mesh). The porosity of the films is in the range of 2-4 µm as characterized by scanning electron microscope. The drug coated medical implants were characterized for their surface and bulk morphology, the degradation rate of the film, drug release rate and cell cytotoxicity. The results suggest that the use of breath figure morphologies in biodegradable polymer films adds an additional level of control to drug release. In comparison to non-porous films, the breath figure films showed an increased degradation and enhanced drug release. Furthermore, the porous nature of the film was investigated as a biomaterial scaffold to construct three dimensional in vitro tissue model systems. The breath figure film with interconnected pores facilitates cell infiltration and tissue remodelling in vitro, suggesting its high potential in regenerative medicine and tissue engineering applications. In the second part of the dissertation, the versatility of breath figure polymers was explored as a reverse template to create micropatterned soft materials. Unlike traditional lithographic masters, the breath figure assembly is a simple and cost-effective approach to create micro/nano sized “bead†like uniform patterns on the surface of hydrogels and biopolymers. By incorporating iron nanoparticles into the pores, this technique was extended to form hydrogels decorated with nanoparticles specifically in the pattern. The morphology features and the functional characteristics were demonstrated through scanning electron microscopy. The potential applications of these micro-fabricated materials in biosensors and cell culture substrates are outlined. / acase@tulane.edu