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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.
1

Caring for the radial artery post-angiogram: A pilot study on a comparison of three methods of compression

Fech, Jennifer 11 1900 (has links)
A coronary angiogram (CATH) is the diagnostic tool used to visualize the coronary arteries of a persons heart. These arteries can be accessed through the radial artery. Various methods of applying compression to the radial puncture site have been used, but no research has been done to show what best practice is. The purpose of this pilot study was to compare two devices and three methods for achieving hemostasis after a transradial angiogram while assessing vascular complications and time endpoints. A mechanical device (Terumo TR wristband) and a hydrophilic wound dressing (Clo-Sur P.A.D.) were used. The Terumo band was studied twice, using the current method and a fast-release method. Taking into account the small sample size of this pilot study, statistically significant differences are seen in time to discharge in the fast-release Terumo and Clo-Sur P.A.D. groups, as compared with the control Terumo group, without increasing vascular complications.
2

Caring for the radial artery post-angiogram: A pilot study on a comparison of three methods of compression

Fech, Jennifer Unknown Date
No description available.
3

An Evidence-Based Approach to Percutaneous Coronary Intervention Access

Sanni, Kemi Funlayo 01 January 2018 (has links)
Coronary heart disease is a significant cause of mortality and morbidity in the United States; Healthy People 2020 set an objective to reduce the rate of the disease by 20% to the baseline rate of 126 deaths per 100,000 population per year. In the local healthcare setting, heart disease was responsible for a high percentage of mortality and morbidity. To address this, the local site developed a plan to improve outcomes for patients seeking care at the facility. Because the femoral approach to percutaneous coronary intervention (PCI) was used to treat coronary heart conditions at the site and complications were frequent, a quality improvement initiative was begun that included a shift to the use of radial artery PCI. The purpose of this project was to evaluate whether the new approach lowered the complication rates. The project focused question asked how the complication rate of transradial and transfemoral approach to PCI compared. Data from nonrandom aggregate PCI results for 158 adult patients, ages 40-80 years; data from the National Cardiovascular Data Registry; and summarized unit reports were used to compare the transfemoral and transradial outcomes. Two-samples t test results indicated the complications were clinically and significantly lower (p < .01) with patients who underwent the transradial approach (n = 82) compared to those who had the transfemoral approach (n = 76). Study results suggest the new initiative using the transradial approach for PCI reduced the complications for patients undergoing PCI at the site. Positive social change is possible as the morbidity and mortality rates were reduced and consumers who need the procedure may experience a lower burden of physical and fiscal cost.
4

Outcomes Following Percutaneous Coronary Intervention Before, During, and After Transition to a Default Transradial Approach at a Veterans Affairs Medical Center

Bagai, Jayant, Bhuiyan, Azad R., White, Christopher J., Mukherjee, Debabrata, Paul, Timir K. 01 August 2020 (has links)
Transradial coronary intervention (TRI) lowers bleeding and mortality compared with transfemoral coronary intervention (TFI). There are limited data on outcomes as TFI operators transition to a default TRI practice. The aim of this study was to assess TFI and TRI outcomes before, during, and after the year TRI was first learned by femoral operators. Patients undergoing percutaneous coronary intervention (PCI) at a Veterans Affairs Medical Center from 2006 to 2012 were included. In 2009, TRI was learned by all operators and then used as the default PCI approach from 2010 to 2012. Baseline characteristics and outcomes were collected. Predictors of major bleeding, major adverse cardiovascular events (MACE), and mortality were determined by multivariable analysis; 1192 veterans were included. TRI rates were 9% (2006-2008), 65% (2009), and 90% (2010-2012). Incidence of 1-year MACE and mortality was 5.4% and 3.9%, respectively, in 2009, and 5.6% and 3%, respectively, during 2010 to 2012. Major bleeding remained at <1%. Age, glycoprotein IIb/IIIa inhibitors, and ST-elevation myocardial infarction were independently associated with major bleeding, whereas TRI was protective. Transition to default TRI is feasible over a short time period and associated with low rates of MACE and mortality and very low rate of major bleeding.
5

Modeling Upper Body Kinematics While Using a Transradial Prosthesis

Lura, Derek J 07 November 2008 (has links)
The prostheses used by the majority of persons with upper limb amputations today offer a limited range of motion. Relative to anatomical joints transradial (below the elbow) prosthesis users lose at least two of the three degrees of freedom provided by the wrist and forearm. Some myoeletric prostheses currently allow for forearm pronation and supination (rotation about an axis parallel to the forearm) and the operation of a powered prosthetic hand. Body-powered prostheses, incorporating hooks and other cable driven terminal devices, have even fewer active degrees of freedom. In order to perform activities of daily living, an amputee must use a greater than normal range of movement from other anatomical body joints to compensate for the loss of movement caused by the amputation. By studying this compensatory motion of prosthetic users, the mechanics of how they adapt to the loss of range of motion in a given limb and specific tasks were analyzed. The purpose of this study is to create a robotic based kinematic model that can predict the compensatory motion of a given task using given subject data in select tasks. The tasks used in this study are the activities of daily living: opening a door, drinking from a cup, lifting a box, and turning a steering wheel. For the model the joint angles necessary to accomplish a task are calculated by a simulation for a set of prostheses and tasks. The simulation contains a set of configurations that are represented by parameters that consist of the joint degrees of freedom provided by each prosthesis, and a set of task information that includes joint constraints and trajectories. In the simulation the hand or prosthesis follows the trajectory to perform the task. Analysis of tasks is done by attaching prosthetic constraints to one of the arms of the upper body model in the simulation, other arm maintains an anatomical configuration. By running the model through this simulation with different configurations the compensatory motions were found. Results can then be used to select the best prosthesis for a given user, design prostheses that are more effective at selected tasks, and demonstrate some possible compensations given a set of residual joint limitations with certain prosthetic components, by optimizing the configuration of the prostheses to improve their performance.
6

An investigation of electromyographic (EMG) control of dextrous hand prostheses for transradial amputees

Ali, Ali Hussein January 2013 (has links)
There are many amputees around the world who have lost a limb through conflict, disease or an accident. Upper-limb prostheses controlled using surface Electromyography (sEMG) offer a solution to help the amputees; however, their functionality is limited by the small number of movements they can perform and their slow reaction times. Pattern recognition (PR)-based EMG control has been proposed to improve the functional performance of prostheses. It is a very promising approach, offering intuitive control, fast reaction times and the ability to control a large number of degrees of freedom (DOF). However, prostheses controlled with PR systems are not available for everyday use by amputees, because there are many major challenges and practical problems that need to be addressed before clinical implementation is possible. These include lack of individual finger control, an impractically large number of EMG electrodes, and the lack of deployment protocols for EMG electrodes site selection and movement optimisation. Moreover, the inability of PR systems to handle multiple forces is a further practical problem that needs to be addressed. The main aim of this project is to investigate the research challenges mentioned above via non-invasive EMG signal acquisition, and to propose practical solutions to help amputees. In a series of experiments, the PR systems presented here were tested with EMG signals acquired from seven transradial amputees, which is unique to this project. Previous studies have been conducted using non-amputees. In this work, the challenges described are addressed and a new protocol is proposed that delivers a fast clinical deployment of multi-functional upper limb prostheses controlled by PR systems. Controlling finger movement is a step towards the restoration of lost human capabilities, and is psychologically important, as well as physically. A central thread running through this work is the assertion that no two amputees are the same, each suffering different injuries and retaining differing nerve and muscle structures. This work is very much about individualised healthcare, and aims to provide the best possible solution for each affected individual on a case-by-case basis. Therefore, the approach has been to optimise the solution (in terms of function and reliability) for each individual, as opposed to developing a generic solution, where performance is optimised against a test population. This work is unique, in that it contributes to improving the quality of life for each individual amputee by optimising function and reliability. The main four contributions of the thesis are as follows: 1- Individual finger control was achieved with high accuracy for a large number of finger movements, using six optimally placed sEMG channels. This was validated on EMG signals for ten non-amputee and six amputee subjects. Thumb movements were classified successfully with high accuracy for the first time. The outcome of this investigation will help to add more movements to the prosthesis, and reduce hardware and computational complexity. 2- A new subject-specific protocol for sEMG site selection and reliable movement subset optimisation, based on the amputee’s needs, has been proposed and validated on seven amputees. This protocol will help clinicians to perform an efficient and fast deployment of prostheses, by finding the optimal number and locations of EMG channels. It will also find a reliable subset of movements that can be achieved with high performance. 3- The relationship between the force of contraction and the statistics of EMG signals has been investigated, utilising an experimental design where visual feedback from a Myoelectric Control Interface (MCI) helped the participants to produce the correct level of force. Kurtosis values were found to decrease monotonically when the contraction level increased, thus indicating that kurtosis can be used to distinguish different forces of contractions. 4- The real practical problem of the degradation of classification performance as a result of the variation of force levels during daily use of the prosthesis has been investigated, and solved by proposing a training approach and the use of a robust feature extraction method, based on the spectrum. The recommendations of this investigation improve the practical robustness of prostheses controlled with PR systems and progress a step further towards clinical implementation and improving the quality of life of amputees. The project showed that PR systems achieved a reliable performance for a large number of amputees, taking into account real life issues such as individual finger control for high dexterity, the effect of force level variation, and optimisation of the movements and EMG channels for each individual amputee. The findings of this thesis showed that the PR systems need to be appropriately tuned before usage, such as training with multiple forces to help to reduce the effect of force variation, aiming to improve practical robustness, and also finding the optimal EMG channel for each amputee, to improve the PR system’s performance. The outcome of this research enables the implementation of PR systems in real prostheses that can be used by amputees.
7

Understanding the role of endothelial progenitor cells in vascular injury and repair

Mitchell, Andrew Joseph January 2018 (has links)
Introduction: Vascular injury is the crucial initiating event in atherosclerosis and is universal following percutaneous coronary intervention. The cellular response to this injury largely determines vessel outcome. Endothelial progenitor cells (EPCs) and their progeny, late outgrowth endothelial cells (EOCs) are thought to play an important role in this process and characterising this role would be valuable in better understanding vascular injury and repair. Methods: The radial artery in the context of transradial cardiac catheterisation was examined as a model of vascular injury with characterisation of structural injury, longitudinal function and EPC populations. To examine the role of late outgrowth endothelial cells a method for GMP-compliant cell culture and labelling with F18Fluorodeoxyglucose was developed with a view to conducting a cell-tracking study of human administration. Results: Radial artery function was reduced following transradial cardiac catheterisation with recovery over a period of three months. There was no correlation between recovery of arterial function and EPC populations as defined by conventional surface markers. A research grade protocol for EOC culture was successfully translated to a GMP-compliant process producing a viable, phenotypically homogeneous EOC product. Cells were successfully labelled with F18Fluorodeoxyglucose and whilst proliferation was reduced, acute viability and function were not compromised. Conclusion: The radial artery in the context of transradial cardiac catheterisation is a useful model of vascular injury and repair although recovery of vascular function does not appear to be influenced by EPC populations. GMP-compliant culture and labelling of EOCs is feasible and will allow examination of the physiology of these cells in vivo in man.
8

Achieving New Standards in Prosthetic Socket Manufacturing

Gharechaie, Arman Tommy, Darab, Omid January 2019 (has links)
Preface: The research about product development of a prosthetic socket was conducted by two students from Mälardalen University, department of Innovation, Design, and Technology. Background: The most recent public survey shows that an estimated 5 million people in China are amputees, out of which a significantly large portion are below-elbow amputees. Sockets sold to below-elbow amputees are equipped with only two surface electromyography sensors, has low comfortability, has problems with perspiration, and a high weight. The current standard for socket manufacturing has not changed in decades. Research Questions: The following research questions have determined the direction of the research: (1) What measurable factors contribute to a convenient and ergonomic feature design in prosthetic socket from the end-user’s perspective? (2) How can the weight and functionality be improved to achieve a prosthetic socket more suited to the end-user, with respect to the existing prosthetic socket? (3) Which material and manufacturing method is suitable for producing cost-effective and customized prosthetic sockets? Research Method: The research was guided by the 5th edition of Product Design and Development by Ulrich &amp; Eppinger (2012) where the product development process described in five of the six phases from planning to test and refinement were utilized. The data collection and analysis techniques performed in this research was guided by Research Methods for Students, Academics and Professionals by Williamson &amp; Bow (2002). Interviews were conducted with five different stakeholders to find specifications of requirements and concretize subjectivism of what defines quality and ergonomics. Implementation: Currently, below-elbow amputees order sockets from orthopedic clinics. The socket was identified as a product of Ottobock. Investigations were made to find optimal solutions to the specification of requirements. Results: The development of a socket concept was designed for additive manufacturing using a multi-jet fusion printer. Analysis: This concept had significant improvements to parameters: higher grade of customizability, 30 % reduced weight, 48 % cost reduction, a new production workflow with 93,5 % automation, and a 69 % reduction in manual work hours. Conclusions: The data of the research strongly indicate existing potentials in enhancing socket design techniques and outputs by implementation of additive manufacturing processes. This can prove to be beneficial for achieving more competitive prosthetics and associated services. / Förord: Denna forskning om produktutvecklingsprocessen av en armprotes genomfördes av två studenter från Mälardalens universitet, avdelningen för innovation, design och teknik. Bakgrund: Den senaste offentliga undersökningen visar att cirka 5 miljoner människor i Kina är amputerade, varav en betydligt stor del är under-armbågsamputerade. Armproteser som säljs till underarmsamputerade individer är utrustade med endast två yt-elektromyografiska sensorer, har låg komfort, har problem med perspiration och hög vikt. Den nuvarande standarden för armproteser har inte förändrats under årtionden. Forskningsfrågor: Följande forskningsfrågor har bestämt riktningen för forskningen: (1) Vilka mätbara faktorer bidrar till en praktisk och ergonomisk funktionsdesign i underarmsproteser ur slutanvändarens perspektiv? (2) Hur kan vikten och funktionaliteten förbättras för att åstadkomma en underarmsprotes som är bättre anpassad för slutanvändaren med avseende på den befintliga underarmsprotesen? (3) Vilket material och tillverkningsmetod är lämpligt för att producera kostnadseffektiva och anpassade underarmsproteser? Forskningsmetod: Forskningsmetoden styrdes av den femte upplagan av Product Design and Development av Ulrich &amp; Eppinger (2012) där produktutvecklingsprocessen är uppdelad i sex faser. I denna forskning användes de fem första faserna från planering till testning och justering. Tekniker för datainsamling och analys som användes i denna forskning styrdes av Research Methods for Students, Academics and Professionals av Williamson &amp; Bow (2002). Intervjuer genomfördes med fem olika intressenter för att hitta kravspecifikationer och för att konkretisera subjektivitet för vad som definierar kvalitet och ergonomi. Implementering:  Underarmsamputerade individer beställer för närvarande armproteser från ortopediska kliniker. Armprotesen identifierades som en produkt av Ottobock. Undersökningar gjordes för att hitta optimala lösningar för kravspecifikationen. Resultat: Konceptutvecklingen av en armprotes utformades för additiv tillverkning med hjälp av en multi-jet-fusion-skrivare. Analys: Det här konceptet hade betydande förbättringar av parametrar: högre grad av anpassningsbarhet, 30 % minskad vikt, 48 % kostnadsreduktion, ett nytt produktionsflöde med 93,5 % automatisering och en 69 % minskning av manuella arbetstider. Slutsatser: Data från denna forskning indikerar att det finns starkt potential för att förbättra designtekniker och utgångar av underarmsproteser genom implementering av additiva tillverkningsprocesser. Detta kan visa sig vara fördelaktigt för att uppnå mer konkurrenskraftiga proteser och tillhörande tjänster.

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