Class of 2014 Abstract / Specific Aims: The main objectives of the study are to compare the number of antihypertensive medications upon admission versus discharge, determine the fluctuation index ((SBPmax – SBPmin)/Avg)x100) between inpatient HD sessions, determine the minimum SBP during each inpatient HD session and compare pre-HD weight to post-HD weight for each inpatient HD session to determine inter-dialytic weight gain. The findings of this study are expected to have a positive impact on the management of blood pressure and fluid overload in HD patients by identifying the adverse effects associated with an increased anti-hypertensive medication burden. Methods: The Institutional Review Board approved this retrospective chart review. The electronic medical record system identified patients that received HD between January 1, 2010 and January 1, 2013. The following data was collected: the admission diagnosis and patient comorbidities; time on dialysis prior to admission and time since last HD session; the number and class of anti-hypertensive medications documented on admission, while inpatient, and upon discharge; the use of midodrine, receipt of erythropoietin stimulating agents, total time on dialysis while admitted, intra-dialytic hypotensive events, blood pressure readings pre- and post-HD, and inter-dialytic weight gain. Descriptive and demographic variables were also collected from the electronic medical record systems. The investigators will use this information to compare the number of anti-hypertensive medications upon admission versus discharge, determine the fluctuation of systolic blood pressure (SBP) between each inpatient HD session, determine the minimum SBP during each inpatient HD session and compare pre-HD weight to post-HD weight to determine inter-dialytic weight gain and total volume removed per each HD session. Descriptive statistics will be used to analyze our demographic data. Multiple linear regression analyses will be completed to evaluate independent predictors of inter-dialytic weight gain and intra-dialytic hypotension. Main Results: Pending Conclusion: Pending

An experimental study was undertaken to answer the question posed by the problem: "Does a nursing intervention which utilizes a decisionmaking model to assist patients in establishing personal goals for adherence to fluid and potassium restrictions significantly decrease weight gains between dialyses and pre-dialysis serum potassium levels, compared with the values for these variables in a control group which does not have the intervention?" Sixteen chronic hemodialysis patients from one large teaching hospital were selected according to pre-established criteria, and then randomly assigned to either experimental or control conditions. The Experimental group was exposed to the nursing intervention, which was the independent variable. The nursing intervention consisted of an initial interview, during which the patients completed a Balance Sheet Procedure, and established personal goals for weight gain between dialyses and pre-dialysis serum potassium levels. Thereafter, for a period of five weeks, the patients in the Experimental group completed a Well-Being Rating Scale at each dialysis and charted their progress toward their goals on a Progress Sheet. The dependent variables were between dialyses weight gains and pre-dialysis serum potassium levels. Data Pertaining to the dependent variables were collected on both Experimental and Control patients in all three phases of the study: the six month Pre-Intervention Phase, the five week Intervention Phase, and the three week Follow-Up Phase. The Theoretical Framework on which the study was based is Jam's and Mann's Conflict Theory (1968), and their Balance Sheet Procedure, which was used to facilitate personal decision-making and goal setting by patients in relation to between dialyses weight gains and pre-dialysis serum potassium levels. The results indicated that the Experimental group obtained significantly lower pre-dialysis serum potassium levels during the Intervention Phase than the Control group, but there were no significant differences between the two groups in weight gains between dialyses. The Well-Being Rating Scales completed by the Experimental patients indicated that well-being tended to increase slightly over the study period, and was significantly related to the achievement of the goals the patient had established for weight gains and potassium levels. A negative correlation was found between well-being and weight gain. The implications of these findings for the nursing care of hemodialysis patients are discussed, and recommendations for further research are presented. / Applied Science, Faculty of / Nursing, School of / Graduate

Objective: Several studies have demonstrated that end-stage renal disease (ESRD) patients on dialysis are at higher risk for cerebrovascular events, especially those on hemodialysis. However, the risk of stroke in patients on peritoneal dialysis (PD) compared to those on hemodialysis (HD) remains unclear. We performed this meta-analysis to assess the risks of stroke in ESRD patients on PD compared to HD. Methods: A systematic review was conducted using MEDLINE, EMBASE, Cochrane databases from inception through January 2018 to identify studies that evaluated the risks of stroke (all types of stroke, ischemic stroke or hemorrhagic stroke) in ESRD patients on different dialysis modalities. Effect estimates from the individual study were extracted and combined using random-effect, generic inverse variance method of DerSimonian and Laird. Results: Fifteen cohort studies with a total of 1 289 572 ESRD patients (over 1 140 942 on HD and 122 534 on PD) were enrolled. Compared with HD, PD was associated with a significantly decreased risk of hemorrhagic stroke with pooled OR of 0.84 (95% CI: 0.76-0.92). However, there were no differences in risks of all types of stroke or ischemic stroke in those on PD compared to HD with pooled ORs of 1.06 (95% CI: 0.91-1.22) and 1.01 (95% CI: 0.80-1.18,), respectively. Conclusions: PD status is associated with 16% lower risk of hemorrhagic stroke compared to HD, but the risks of all types of stroke and hemorrhagic stroke are not statistically different in PD patients when compared to HD patients.

京都大学 / 0048 / 新制・課程博士 / 博士(社会健康医学) / 甲第20624号 / 社医博第82号 / 社新制||医||9(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 木原 正博, 教授 古川 壽亮, 教授 柳田 素子 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM

Thromboembolism (TE) significantly limits the usefulness and safety of blood-contacting devices such as hemodialysis catheters. Computer simulation of TE can provide understanding of the process and can facilitate the design of more effective devices. Previous work conducted at BYU successfully modeled TE in a simple, two-dimensional flow cell design by adding quantitative TE code to a commercial computational fluid dynamics (CFD) package, Fluent. This two-dimensional model predicted thrombus initiation and growth and adjusted flow to accommodate thrombus geometries, but was limited by computational power and unsophisticated meshing techniques. To build upon this work, and take advantage of BYU's new supercomputing system and improvements in automatic meshing software, development of a three-dimensional computational model of thrombosis in three hemodialysis catheters designs was undertaken. Development of the computer model was beset with challenges associated with limitations in both software and hardware, but those challenges were ultimately overcome as both software and hardware evolved. Eventually, the previous C-based Fluent model was ported to the Fortran-based STAR-CD model successfully. A computer geometry of a blood flow cell matching the geometry used with the previous two-dimensional model was created, and results for that geometry using the new computer compared favorably with the results from the previous model. Catheter geometries were created using computer-aided design (CAD) software and were meshed using auto-meshing software. CFD analysis identified potentially-troublesome flow regimes in the catheter designs that coincided with thrombotic regimes observed in preliminary experiments using those same catheter designs. The TE model is now ready for application to the catheter geometries and for rigorous testing (e.g., grid-independence, in-depth comparison with quantitative experiments, etc.).

To prevent clotting during dialysis, heparin is used to line the tubing which blood flows through. Unfortunately, many side effects arise from taking heparin, especially when it is used for an extended period of time. As such, long-term exposure for individuals undergoing dialysis every day is unavoidable. To prevent the solubilized heparin from entering the bloodstream, a polymer-based natural material is being investigated. This materials properties include reduction of coagulation and elimination of the long-term effects of heparin such as heparin induced thrombocytopenia and osteoporosis. Cellulose nanocrystals (CNCs) contain the same 1,4 linked pyranose backbone structure as heparin along with desirable mechanical properties, like high stiffness and anisotropic shape. By altering the functionalization on the surface of CNCs to closely mirror that of heparin, it should be possible to make a biomimetic material that counteracts blood clotting, while not introducing soluble small molecule anti-coagulants into the body. Through blood assays and platelet fixing analysis, we have been able to show that this change in functionalization does reduce coagulation. Surface chemistry of CNCs were modified from 'plain' CNCs (70 mmol SO3-/kg residual from hydrolysis) to 500 mmol COO-/kg (TEMPO oxidized) and 330 mmol SO3-/kg CNC (sulfonated CNCs). We will show that by utilizing CNCs reactive functional groups and incredible mechanical properties we are able to create a material that reduces clotting while maintaining the tubing's mechanical strength as well as eliminating heparin's side effects associated with it being a soluble anticoagulant. / MS / To prevent clotting during dialysis, heparin is used to line the tubing which blood flows through. Heparin, an anticoagulant, is more commonly known as a ‘blood thinner’ which is a misnomer because it does not actually thin blood. Heparin works by inhibiting clotting factors in the coagulation cascade pathway which in turn limit the formation of blood clots and create the ‘thinning’ effect mentioned earlier. When dialysis is performed the interaction between blood and the dialyzer tubing initiates the formation of a blood clot. This is where heparin use comes in. Unfortunately, many side effects arise from taking heparin, especially when it is used for an extended period of time. As such, long-term exposure for individuals undergoing dialysis every day is unavoidable. To prevent heparin or its mimics from entering the bloodstream, a polymer-based natural material is being investigated. The properties of this material will include reduction of coagulation and elimination of the long-term effects of heparin. The polymer-based natural material being investigated is cellulose nanocrystals (CNCs). CNCs contain the same ring structure and chemical linkage sites as heparin along with desirable mechanical properties. By altering the surface chemistry on the CNCs to closely mirror that of heparin, it should be possible to make a biomimetic material that counteracts blood clotting, while not introducing a solution based small molecule anticoagulant to the body. Through blood assays and platelet fixing analysis, we have been able to show that this change in functionalization does reduce coagulation. The ‘plain’ CNCs used contained an initial charge density of 70 mmol SO₃⁻ /kg. This residual charge density was a result from the acid hydrolysis performed to acquire CNCs from cellulose. Chemically modified CNCs contained many more negatively charged functional groups with TEMPO oxidized and sulfated CNCs having 500 mmol COO⁻/kg and 330 mmol SO₃⁻ /kg, respectively. We will show that by utilizing CNCs reactive functional groups and incredible mechanical properties we are able to create a material that reduces clotting while maintaining the tubing’s mechanical strength as well as eliminating heparin’s side effects associated with it being a soluble anti-coagulant.

Extracorporeal circulation damages blood and causes harmful side effects such as stroke and/or systemic inflammatory response in patients. Reactions of blood components to extracorporeal circulation include complement and inflammatory reactions, coagulation and thrombogenesis, frank hemolysis, and platelet activation and adhesion to the extracorporeal circuit. Non-physiologic pressure and flow produced by blood pumps contribute to blood injury. Two pump types, roller and centrifugal, are used for maintaining flow, with various models available from different manufacturers. This study compared the effects of these two pumps in identical, isolated, artificial circuits to a non-pumped control for a period of 24 hours on heparinized porcine blood. Hematology parameters were used to evaluate blood damage. Mean corpuscular volume, mean corpuscular hemoglobin, white blood cell count, platelet count, and mean platelet volume were affected by time of circulation. Mean corpuscular hemoglobin, platelet count, and red cell distribution width were different between circulated and non-circulated blood, however no differences were found between the pumping systems in any parameter. Red blood cell count, total hemoglobin, and hematocrit were not affected by time or treatment. The changes observed in this study have implications for the use of extracorporeal circulation in the clinical setting and in future use of blood as a potential organ perfusion medium. / Master of Science

Five changes were suggested to improve the kidney dialysis machine, including a conductivity control feedback system, a positive pressure deaeration system, a balancing system for dialysate flow control, a diaphragm-type blood pump, and an ultrafiltration control system using blood pressure measurement. A kidney dialysis machine was constructed to test the changes for possible use in future dialysis machine designs. Tests were made on each of the five system improvements. All five ideas had some merit for a commercial dialysis machine. A description of the investigation and the various factors used in the development and testing of the five systems is included. / Master of Science

The effects of a monetary reward and self-monitoring on reducing interdialytic weight gain (IWG) were compared for 6 hemodialysis patients in an outpatient setting. A single-subject experimental design (A-B-BC-B-BC) was used to examine each variable individually and in combination, with alternating phases to control for possible sequencing effects. Monetary reward (50 cents - $3) was administered in a titrated manner according to standardized criteria, ranging from 3 % and 4% of patients' dry weight on weekdays and weekends, respectively, to 3.5% and 4.5% for weekdays and weekends. Self-monitoring involved recording daily fluid and diet intake. Results indicated that by the end of the treatment program, the 6 participants averaged a 14% reduction in weekday IWG and a 15.45% reduction in weekend IWG; however, due to significant variability, it cannot be concluded that the reductions are treatment effects. Four out of 6 participants reduced their average IWG for both weekends and weekdays by .75 kg (1.65 lb.). The average weekend reduction for these 4 participants was .85 kg (1.87 lbs.) while the average weekday reduction was .65 kg (1.43 lb.). All 6 participants showed reductions in weekday IWG that averaged .53 kg (1.17 lb.). However, only 2 participants demonstrated IWG reductions that could be attributable to either of the 2 treatment variables. The standardized dry weight criterion for assessing fluid adherence may have posed excessively stringent demands on participants, as only 1 of the 6 participants actually met the criterion. Future research should address the role of nonspecific treatment factors, as well as patient characteristics and responsivity to particular treatment components in an effort to identify those factors responsible for behavior change in this population.

M.A. / Modern health-care services in general hospital settings are often characterised by mUltidisciplinary and interdisciplinary approaches to patient care. The underlying rationale of these approaches lies in the potential pooling of specialised medical resources from a variety of medical fields. Consequently there is usually an increase in the diagnostic procedures available, theoretically offering a more comprehensive health service. Whilst the above approach is seen to be effective when the health-car~ team specialists subscribe to one encompassing paradigm, it is hypothesised that the existence of other alternative paradigms may affect the efficacy of team work. Using the interface between the Psychology and Renal units of J.G. Strijdom Hospital as an example, this study describes the effect of paradigmatic differences within a team approach on the conceptualisation of problems and treatment choices. The traditional medical approach is contrasted against a systems based psychological approach. The existence of the two approaches within a single team encounters difficulty in the gaining of consensus regarding the level of focus.