Thesis (M.S.)--University of Michigan, 1986.

Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Angela P. Clark. Vita. Includes bibliographical references.

Patients who are critically ill get often admitted to intensive care units (ICUs). The majority of these patients require support with their breathing and are thus connected to a mechanical ventilator. One aspect to consider in the mechanically ventilated patient is endotracheal tube cuff pressure (ETT) management. The management of ETT cuff pressure entails that nurses working in ICUs have the responsibility of ensuring that ETT cuff pressure is kept within normal range of 20-30 cmH20 for the safety of the patients in order to avoid complication of over and under inflation. Poor management of ETT cuff pressure places the mechanically ventilated patients under risk of tracheal injury. Tracheal injury may also be caused by over or under inflation of the ETT cuff. Over inflation of the ETT cuff can lead to the occlusion of capillaries lining the trachea at the cuff site, tracheal stenosis, and can also lead to the death of mucus membranes around the area, just to mention a few. On the other hand, under inflation of the ETT cuff, can lead to air leaks as well as aspiration of gastric contents into the tracheal tree. Therefore, in order to maintain ETT cuff pressure within normal ranges, evidence-based guidelines related to the management of ETT cuff pressure should be used. However, in Malawi the management of endotracheal tube cuff pressure in mechanically ventilated adult patients by nurses in ICUs is not well explored and it is not clear whether this practice is based on evidence-based guidelines. Furthermore, strategies on how to implement evidence-based guidelines in the ICU might not be known and poorly defined because of the complexity of the context. The study is therefore aimed at implementing and evaluating the effect of an evidence-based guideline on the management of ETT cuff pressure in mechanically ventilated adult patients by nurses in ICUs in Malawi using active (printed educational materials and monitoring visits) and passive (printed educational materials only) implementation strategies. The research study used a quantitative approach with multi-designs. Four phases were used in order to achieve the four objectives that were set. Phase one was the pre-test and used a survey design, two was the expert panel review of the evidence-based guideline, three was the implementation of the reviewed evidence-based guideline using a randomised controlled trial design and phase four was the post-test which used a survey design. The RCT included 25 participants from the control and 27 from the intervention group. Each group had three ICUs of which one in each group was from a private hospital and the other were government. Data collection in phases one and four was by a hand delivered pre-and post-questionnaire. In phase two the expert panel members with experience in critical care used the AGREE II Instrument to review the evidence-based guideline that was implemented. In order to gather data during the monitoring visits, the researcher recorded field notes. The applications that were developed by the University statistician consultant using visual basic applications in excel were used to analyse data. Two different implementation strategies were used to implement the evidence-based guideline. The control group used passive implementation strategy which was printed educational materials thus the evidence-based guideline and algorithm. The intervention group used both active and passive implementation strategies which was the printed educational materials thus the evidence-based guideline and algorithm plus monitoring visits by the researcher. In order to establish the effect of the implemented evidence-based guideline on the nursing care practice for the management of endotracheal tube cuff pressure an evaluative posttest survey was conducted in phase four of the research study. The results revealed that the majority of participants had gaps in both groups regarding nursing care practice for the management of endotracheal tube cuff pressure for the mechanically ventilated adult patients in the pretest but improved in the posttest. In the control group 52% had very low knowledge score, 16% had low score, 28% average, and 4% high score while in the category of very high score there was nobody. However, in the posttest those in the very low score were only 44% while the percentage in the low score remained 16%. There was an improvement in the average scores in the posttest such that only 44% were in this category. There was no one in the high and very high score in the pretest. On the other hand, in the intervention group, 78% had a very low score, 9% low score, and 13% were in the category of average score, while in the high and very high score category there was zero percent in the pretest. However, there was also an improvement in the posttest such that only 44% a very low knowledge score. But 19% had a low score, there were 37% in the average category and no one was in the high and very high score. Statistical analysis revealed that the results were not significantly different between and within groups. Improvements were observed in the two groups regarding the scientific knowledge scores for the nursing care practices in the posttest. Upon qualitative analysis of the data from the open-ended question, two main themes emerged thus the need for documentation of endotracheal tube cuff and the process of implementation the evidence-based guidelines. Sub themes such as lack of documentation; no part of routine care and monitoring not done at all were identified under the main theme of the need for documentation of ETT cuff pressure. The Guideline itself need to be clear; implementation strategies; follow up; incentives; supervision; incentives; time factor; resources or equipment required for successful implementation; nurses buy-in critical for the implementation; training detrimental to EBP implementation; nurses attitude crucial to implementation of EBGs and knowledge of nurses for guideline essential for the implementation were the sub themes identified under the main theme of the process of implementing the evidence-based guideline. All appropriate ethical considerations such as principles of autonomy and self-determination, confidentiality and anonymity, voluntary participation, right to receive treatment, informed consent, were adhered to throughout the research study. The research study was unique in nature because it was the first of its kind in Malawi and it contributed to the awareness of the recommended practice for management of endotracheal tube cuff pressure in the ICUs in the country by implementing an evidence-based guideline. The unique contribution of the study is that it is a challenge to implement evidence-based guideline in poor and resource constraint countries like Malawi.

Summary: Although the digital revolution has transformed many niches of human activity, healthcare sector and pharmaceutical drug development has been relatively slow in embracing emerging technologies to optimize health efficacy, especially in Nordic Countries. The topic is of more importance now owing to the present scenario of the corona virus (COVID-19)outbreak, which has caused unparalleled disruption in the conduct of clinical trials and presented challenges as well as opportunities for clinical trialists and data analysts. In this master thesis, the potential opportunity with virtual or digital clinical trials as viable options to enhance drug development efficiency is highlighted that offers diverse patients easier and attractive ways to participate in clinical trials. Special reference is made to wearable devices in clinical trial execution and generating real world data; its acquisition and processing in a virtual trial setting. Issues of patient safety, measurement reliability and validity, and data privacy & integrity are  reviewed, and considerations are put forward for mitigation of underlying regulatory andoperational barriers. The aim of this thesis is to assess the recent wearable technologies that generate Real World Data and to understand the potential of this data to transform Nordic healthcare industry. A systematic review of clinical trials involving wearable patient monitoring technique in North America, Nordic Countries and other European countries was conducted. Out of various innovative wearable technologies, Smartwatches are found to be the most common and it is also observed that these wearable technologies have been able to help in early detection and diagnosis of diseases and modify disease progression by real time monitoring of data and develop precision medicine. thus, it is concluded that Wearable Remote Patient Monitoring is a novel technique that has few barriers;but promises a big transformation in Nordic Countries as well as in entire healthcare industry.

Abstract Sleep Apnea (SA) is a common disorder that affects approximately 2% of middle-aged women and 4% of middle-aged men. It is characterized by repetitive cessation of breathing during sleep. SA has significant health and social consequences such as daytime sleepiness, impaired quality of life, and in the worst case, myocardial infarction and sudden cardiac death. It has been estimated that approximately 80% of individuals with moderate to severe SA syndrome have not been diagnosed. The lack of patient sleep histories has caused low identification of SA and referral rates, especially in primary care facilities. Moreover, due to the inadequate prevalence of overnight polysomnography (PSG) as a standard clinical test of SA, patients suspected of having this sleep disorder have to wait several months for diagnosis and treatment. The costly and time-consuming nature of PSG and the lack of sleep clinics have created a demand for suitable home-based health monitoring devices. Over the years, several devices have been developed to monitor sleep unobtrusively, while an individual is lying in bed. However, most of these devices would either disrupt the sleep of the patient or be disrupted by the patient during routine bed sheet changes. Pressure measurement using a Pressure Sensitive Mat (PSM) enables a non-contact approach for monitoring patient vital signs such as respiration rate. The PSM has the potential to replace obtrusive breathing sensors in the sleep lab and to be used as a pre-screening tool for patients suspected of having sleep apnea. This thesis proposes multiple algorithms applicable to PSM in order to assess sleep quality. First, fusion techniques are proposed to extract a breathing signal from PSM. Second, a wide range of machine learning approaches including a simple threshold-based algorithm, a linear support vector machine (SVM) and two deep learning methods (i.e., a temporal convolutional network (TCN) and a bidirectional long short-term memory (BiLSTM) network) are compared to find a good- iii performing method for automatically detecting central sleep apnea (CSA) events from PSM signals. The results show that the accuracy of the model with the best performance is 95.1% and it is achieved by the BiLSTM network. Finally, by applying SVM, personalized systems are optimized to investigate long-term sleep pattern changes such as central apnea index (CAI), bed occupancy (BO), day-clock, and night-clock from previously recorded data.

No description available.

Objective: The diagnosis of delirium in intensive care unit patients is frequently missed. Key symptoms to identify delirium are motoric alterations, changes in activity level, and delirium-specific movements. This study aimed to explore features collected by a single wrist-worn accelerometer as indicators of delirium. Methods: The study included twenty-two patients in the intensive care unit. The data was collected with the GENEActiv accelerometer device and the activity level was calculated. Differences between the delirious and nondelirious patients were tested. Results: Differences in activity level and rest-activity patterns were noticed between the delirious and non-delirious patients. However, the differences were not found to be significant. Conclusion: Activity patterns revealed differences between delirious and non‐delirious patients. Further study is required to confirm the potential of actigraphy in the early detection of delirium in the intensive care unit. / Mål: Diagnosen delirium hos intensivvårdspatienter missas ofta. Nyckelsymptom för att identifiera delirium är motoriska förändringar, förändringar i aktivitetsnivå och deliriumspecifika rörelser. Denna studie syftade till att utforska funktioner som samlats in av en enskild handledsburen accelerometer som indikatorer på delirium. Metod: Studien omfattade tjugotvå patienter på intensivvårdsavdelningen. Data samlades in med GENEActiv accelerometerenheten och aktivitetsnivån beräknades. Skillnader mellan de delirious och icke-delirious patienterna testades. Resultat: Skillnader i aktivitetsnivå och viloaktivitetsmönster noterades mellan de deliriösa och icke-deliriösa patienterna. Skillnaderna visade sig dock inte vara signifikanta. Slutsats: Aktivitetsmönster avslöjade skillnader mellan deliriösa och ickedelirösa patienter. Ytterligare studier krävs för att bekräfta potentialen för aktigrafi vid tidig upptäckt av delirium på intensivvårdsavdelningen.

1. An explicit mathematical description of PEP in terms of DBP was proposed, which in the first time quantitatively clarified the ventricular and arterial effects on PEP timing. / 2. A nonlinear pressure-volume relationship which reflected the natural arterial wall properties was introduced into the asymmetric T-tube arterial model, which effectively and quantitatively described the effect of pulsatile BP on arterial parameters, e.g., compliance, PTT etc. / 3. A mathematical relationship between PAT and BP was firstly proposed as a result of the heart-arterial interaction, which simulated a significantly strong and negative relationship between PAT and SBP and between PAT and MBP but a much weaker negative relationship between PAT and DBP during exercise. The hypothesis was supported by the experiment data. To our knowledge, it is the first study describing the quantitative relation of PAT and BP by both model-based study and experimental data. / 4. A novel wearable measurable CO parameter, PTRR, was proposed and it successfully showed a significantly high and positive correlation with CO during exercise both in model simulation and in the experiments. / 5. Linear prediction models using PAT to estimate MBP and using PTRR to estimate CO were proposed and evaluated in two exercise experiments conducted on 84 subjects with different ages and cardiovascular diseases. Results showed the proposed method could achieve the accuracy required for medical diagnosis. / 6. Taken the findings in 3, 4 and 5 together, this study in the first time provided both the theoretical basis and experimental verifications of developing a wearable and direct measurement technique of CPO in dynamic exercise using multiple physiological signals measured on body surface. / Cardiac power output (CPO) is defmed as the product of mean arterial blood pressure (MBP) and cardiac output (CO), and CPO measured during peak dynamic exercise (i.e. peak CPO) has been shown as a powerful predictor of death for heart failure patients. However, so far there has been no existing device which directly measures CPO, and CPO is acquired from simultaneous measurement of MBP and CO. Further, simultaneous MBP and CO measurement during dynamic exercise is a challenge for current BP and CO methods. Therefore, there is an urgent need to develop new devices which are fully wearable and unobtrusive for monitoring of CPO during dynamic exercise. Since the core problem in most wearable devices is how to estimate the target cardiovascular parameter, e.g. CPO in this study, through physiological signals measured from body surface, this thesis focus on developing a direct measurement technique of CPO in dynamic exercise using multiple physiological signals measured on body surface, specifically, electrocardiogram (ECG) and photoplehtysmogram (PPG). / Finally, based on the theoretical and experimental verifications, linear prediction models were proposed to estimate MBP from PAT and estimate CO from PTRR. The results showed that PAT can estimate MBP with a standard deviation of 7.42 mmHg, indicating PAT model has the potential to achieve the accuracy required by AMMI standard (mean error within +/- 5 mmHg and SD less than 8 mmHg). The results also showed that PTRR can estimate CO with a percent error of 22.57%, showing an accuracy which was considered as clinically acceptable (percent error less than 30%). / Heart failure is the end stage of many cardiovascular diseases, such as hypertension, coronary heart disease, diabetes mellitus, etc. Around 5.8 million people in the United States have heart failure and about 670,000 people are diagnosed with it each year. In 2010, heart failure will cost the United States $30.2 billion, and the cost of healthcare services is a major component of this total. With the resultant burden on health care resources it is imperative that heart failure patients with different risk stages are identified, ideally with objective indicators of cardiac dysfunction, in order that appropriate and effective treatment can be instituted. / In order to verify the theoretical findings, two experiments were carried out. One was incremental supine bicycle exercise conducted on 19 young healthy subjects and the other was incremental to maximum supine bicycle exercise conducted on 65 subjects, including heart failure patients, cardiovascular patients and healthy elderly. PAT showed significantly high and negative correlation with SBP and MBP, but lower correlation with DBP. PTRR showed significantly high and positive correlation with CO. / In this thesis, a model based study is conducted to address the above problem. Firstly, we deduced the mathematical expression of PEP as a function of DBP by introducing the arbitrary heart rate into the exponential mathematical description of a pressure-source model. Secondly, an asymmetric T-tube model was modified by introducing a nonlinear pressure-volume relationship where PTT was expressed as a dependent variant of BP. Thirdly, we proposed the mathematical equation between PAT and BP by coupling the modified ventricular and arterial models. Then, the relationships between PAT with systolic blood pressure (SBP), MBP and DBP were simulated under changing heart contractility, preload, heart rate, peripheral resistance, arterial stiffness and a mimic exercise condition. The simulation results indicated significantly high and negative correlations between PAT and SBP and between PAT and MBP whereas the correlation between DBP and PAT was low. / Next, we developed a novel CO index, namely pulse time reflection ratio (PTRR), expressed in terms of MBP and mean aortic reflection coefficient (Gamma(0)), from the modified asymmetric T-tube model. PTRR was further expressed in terms of PAT and inflection point area (IPA), a surrogate of Gamma(0) from the shape feature of PPG. The simulation results suggested significantly and positive relationship between PTRR and CO and between IPA and Gamma(0) during dynamic exercise. / Recently, a wearable measurable parameter, pulse arrival time or PAT, has been developed for BP measurement. PAT is the time delay from the R peak of ECG to the systolic foot of PPG. PAT consists of two timing components, the pre-ejection period (PEP) of the heart and pulse transit time (PTT). PTT is related to BP by an arterial elastic model and thus can be used to estimate beat-to-beat BP. However, PTT is difficult to be measured through a wearable device, and thus PAT is usually used as a surrogate of PTT for BP estimation, under the assumption of a constant PEP. However, PEP is not a constant but changing with physiological conditions, which may alter the PAT-BP relationship. Thus, it is important to clarify the PAT-BP relationship and address the feasibility of MBP estimation using PAT during dynamic exercise. / To summarize, the original contributions of this thesis are: / Wang, Ling. / Adviser: Y.T. Zhang. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Thesis (MPH.) -- University of Limpopo, 2014 / Objective: The purpose of this study was to determine the prevalence of impaired glucose tolerance, impaired fasting glucose, undiagnosed type 2 diabetes and its associated risk factors among adults patients attending the outpatient department of a level one hospital in a rural community of Barkley West, South Africa. Research methodology: This was a cross-sectional survey conducted by a simple random sampling of adults patients F 30 years old. Patients were screened using the American Diabetes Association and the World Health Organisation criteria. First, patients underwent the 75g oral glucose tolerance test and secondly, the 12-hours fasting plasma glucose tests after pre-test results of 5.5 mmol/L were obtained considered as positive for screening. To determine the prevalence of IGT, IFG, and undiagnosed type 2 diabetes; tests were conducted using both the capillary finger puncture and the laboratory methods. To ensure validity and reliability, each patient underwent two tests (fasting and random) by the capillary finger puncture method and two tests (fasting and random) by the laboratory method. Results: Eighty-five (85) questionnaires were distributed, supervised and returned by a research assistant, which brought the response rate to 100%. All patient known living with diabetes mellitus was not included in the study. The prevalence of IGT was 34.1% [34% for females and 9.4% for males] and that for IFG was 23.6% [25% for females and 6.0% for males]. The prevalence of undiagnosed type 2 diabetes discovered during the survey was 9.3% by 2-hours 75g glucose tolerance test [8.2% for females and 1.1% for males] and that by 12-hours fasting plasma glucose, the prevalence was 5.8% [4.7% for females and 1.1% for males].The associated risk factors were physical inactivity, overweight and obesity, unhealthy diet, alcohol consumption, hypertension, smoking habit, family history of diabetes, social deprivation and poverty. The prevalence of hyperglycaemia was also high among female patients due to a higher BMI with 25% overweight (females 18% overweight, males 7% overweight) and 75% obese (females 54% of obesity, males 21% of obesity); higher waist circumference with higher abdominal fat (females 71.7% had a W/C F 88 cm, males 28% had a W/C F 102 cm.); and a larger waist-to-hip ratio (females 61.1% had WHR > 0.85, males 7% had a WHR > 1.0). The sensitivity, specificity, positive and negative predictive values for IGT were 34%, 86%, 25%, and 86% and those for IFG were 24%, 86%, 19%, and 86% respectively. IGT sensitivity was greater than IFG sensitivity. xi Conclusion: There was a high prevalence of IGT, IFG and undiagnosed type 2 diabetes specifically among female patients. The ten percent difference of sensitivity between the two tests showed that the WHO diagnostic criteria produced more patients with the pathology than the ADA diagnostic criteria do. Patients attending the outpatient department of a level one hospital in Barkley West are at high risk of developing type 2 diabetes and remain unidentified, undetected, unscreened, undiagnosed and untreated. Obesity at primary health care level in the rural community of Barkley West needs to be addressed. . Keywords: Impaired glucose tolerance, prevalence, diabetes, screening, anthropometric measurements

ABSTRACT PATIENT MONITORING VIA MOBILE AD HOC NETWORK - MAXIMIZING RELIABILITY WHILE MINIMIZING POWER USAGE AND DELAYS BY SWETA SNEHA May 22nd, 2008 Committee Chair: Dr. Upkar Varshney Major Department: Computer Information Systems Comprehensive monitoring of patients based on wireless and mobile technologies has been proposed for early detection of anomalies, provision of prompt medical attention, and corresponding reduction in healthcare expenses associated with unnecessary hospitalizations and treatment. However the quality and reliability of patient monitoring applications have not been satisfactory, primarily due to their sole dependence on infrastructure-oriented wireless networks such as wide-area cellular networks and wireless LANs with unpredictable and spotty coverage. The current research is exploratory in nature and seeks to investigate the feasibility of leveraging mobile ad hoc network for extending the coverage of infrastructure oriented networks when the coverage from the latter is limited/non-existent. Although exciting, there are several challenges associated with leveraging mobile ad hoc network in the context of patient monitoring. The current research focuses on power management of the low-powered monitoring devices with the goal to maximize reliability and minimize delays. The PRD protocols leveraging variable-rate transmit power and the PM-PRD scheme are designed to achieve the aforementioned objective. The PRD protocols manage power transmitted by the source and intermediate routing devices in end to end signal transmission with the obejective to maximize end to end reliability. The PM-PRD scheme operationalizes an appropriate PRD protocol in end to end signal transmission for diverse patient monitoring scenarios with the objective to maximize reliability, optimize power usage, and minimize delays in end to end signal transmission. Analytical modeling technique is utilized for modeling diverse monitoring scenarios in terms of the independent variables and assessing the performance of the research artifacts in terms of the dependent variables. The evaluation criterion of the research artifacts is maximization of reliability and minimization of power usage and delays for diverse monitoring scenarios. The performance evaluation of the PRD protocols is based on maximization of end to end reliability in signal transmission. The utility of the PM-PRD scheme is associated with operationalizing an appropriate protocol for a given monitoring scenario. Appropriateness of a protocol for a given scenario is based on the performance of the PRD protocols with respect to the dependent variables (i.e., end to end reliability, end to end power usage, and end to end delays). Hence the performance evaluation of the PRD protocols in terms of the dependent variables is utilized to (a) discover the best protocol and (b) validate the accuracy and utility of the PM-PRD scheme in allocating the best protocol for diverse monitoring scenarios. The results validate the effectiveness of the research artifacts in maximizing reliability while minimizing power usage and delays in end to end signal transmission via a multi-hop mobile ad hoc network. Consequently the research establishes the feasibility of multi-hop mobile ad hoc network in supplementing the spotty network coverage of infrastructure oriented networks thereby enhancing the quality and dependability of the process of signal transmission associated with patient monitoring applications.