Detection of Defects in Geomembranes Using Quasi-Active Infrared Thermography.

High-density polyethylene geomembranes are employed as covers for the sewage treatment lagoons at Melbourne Water Corporation's Western Treatment Plant, to harvest the biogas produced during anaerobic degradation, which is then used to generate electricity. Due to its size, inspecting the cover for defects, particularly subsurface defects, can be challenging, as well as the potential for the underside of the membrane to come into contact with different substrates, viz. liquid sewage, scum (consolidated solid matter), and biogas. This paper presents the application of a novel quasi-active thermography inspection method for subsurface defect detection in the geomembrane. The proposed approach utilises ambient sunlight as the input thermal energy and cloud shading as the trigger for thermal transients. Outdoor laboratory-scale experiments were conducted to study the proposed inspection technique. A pyranometer was used to measure the intensity of solar radiation, and an infrared thermal camera was used to measure the surface temperature of the geomembrane. The measured temperature profile was analysed using three different algorithms for thermal transient analysis, based on (i) the cooling constant from Newton's law of cooling, (ii) the peak value of the logarithmic second derivative, and (iii) a frame subtraction method. The outcomes from each algorithm were examined and compared. The results show that, while each algorithm has some limitations, when used in combination the three algorithms could be used to distinguish between different substrates and to determine the presence of subsurface defects.

Achieving dialysis safety: The critical role of higher-functioning teams.

The potential for harm from errors and adverse events in dialysis is significant. Achieving a culture of safety in dialysis to reduce the potential harm to patients has been challenging. Recently, improving dialysis safety has been highlighted by Nephrologists Transforming Dialysis Safety (NTDS), a national initiative to eliminate dialysis infections. Other aspects of dialysis safety are important, though less measurable. Approaching dialysis safety from a systematic thinking view helps us to understand the need for leadership and high-functioning teams to deliver safe, reliable care in dialysis facilities. Resilience in healthcare is embodied by strong teamwork-interdependent professionals working together with clarity of goals and communication. This paper reframes the role of dialysis facility medical directors as leaders of these high-functioning teams. Alignment between nephrologists and dialysis management is necessary for these teams to function. This will require nephrologists to embrace their leadership roles as medical directors and for dialysis facility management to provide adequate operational support. The accountability for dialysis safety is shared between the nephrologists and dialysis organizations; coleadership is required for safety culture and high-functioning dialysis teams to develop.

Leak Detection in Water Pipes Using Submersible Optical Optic-Based Pressure Sensor.

Leakage is undesirable in water distribution networks, as leaky pipes are financially costly both to water utilities and consumers. The ability to detect, locate, and quantify leaks can significantly improve the service delivered. Optical fibre sensors (OFS) have previously demonstrated their capabilities in performing real-time and continuous monitoring of pipe strength leak detection. However, the challenge remains due to the high labour cost and time-consuming process for the installation of optical fibre sensors to existing buried pipelines. The aim of this paper is to evaluate the feasibility of a submersible optical fibre-based pressure sensor that can be deployed without rigid bonding to the pipeline. This paper presents a set of experiments conducted using the proposed sensing strategy for leak detection. The calibrated optical fibre device was used to monitor the internal water pressure in a pipe with simultaneous verification from a pressure gauge. Two different pressure-based leak detection methods were explored. These leak detection methods were based on hydrostatic and pressure transient responses of the optical fibre pressure sensor. Experimental results aided in evaluating the functionality, reliability, and robustness of the submersible optical fibre pressure sensor.

Remote Monitoring of Automated Peritoneal Dialysis Patients: Assessing Clinical and Economic Value.

BACKGROUND: For chronic kidney disease patients who progress to end-stage renal disease, survival is dependent on renal replacement therapy in the form of kidney transplantation or chronic dialysis. Peritoneal dialysis (PD), which can be performed at home, is both more convenient and less costly than hemodialysis that requires three 4-h visits per week to the dialysis facility and complicated equipment. Remote therapy management (RTM), technologies that collect medical information and transmit it to healthcare providers for patient management, has the potential to improve the outcomes of patients receiving automated peritoneal dialysis (APD) at home. OBJECTIVE: Estimate through a simulation study the potential impact of RTM on APD patients use of healthcare resources and costs in the United States, Germany, and Italy. METHODS: Twelve APD patient profiles were developed to reflect potential clinical scenarios of APD therapy. Two versions of each profile were created to simulate healthcare resource use, one assuming use of RTM and one with no RTM. Eleven APD teams (one nephrologist, one nurse) estimated resources that would be used. RESULTS: Results from U.S., German, and Italian clinicians found that RTM could avoid use of 59, 49, and 16 resources over the 12 profiles, respectively. Estimated reduced utilization across the three countries ranged from one to two hospitalizations, one to four home visits, two to five emergency room visits, and four to eight unplanned clinic visits. Total savings across all scenarios were $23,364 in the United States, $11,477 in Germany, and $7,088 in Italy. CONCLUSION: In a simulated environment, early intervention enabled by RTM reduced healthcare resource utilization and associated costs.

Consistency of color representation in smart phones.

One of the barriers to the construction of consistent computer-based color vision tests has been the variety of monitors and computers. Consistency of color on a variety of screens has necessitated calibration of each setup individually. Color vision examination with a carefully controlled display has, as a consequence, been a laboratory rather than a clinical activity. Inevitably, smart phones have become a vehicle for color vision tests. They have the advantage that the processor and screen are associated and there are fewer models of smart phones than permutations of computers and monitors. Colorimetric consistency of display within a model may be a given. It may extend across models from the same manufacturer but is unlikely to extend between manufacturers especially where technologies vary. In this study, we measured the same set of colors in a JPEG file displayed on 11 samples of each of four models of smart phone (iPhone 4s, iPhone5, Samsung Galaxy S3, and Samsung Galaxy S4) using a Photo Research PR-730. The iPhones are white LED backlit LCD and the Samsung are OLEDs. The color gamut varies between models and comparison with sRGB space shows 61%, 85%, 117%, and 110%, respectively. The iPhones differ markedly from the Samsungs and from one another. This indicates that model-specific color lookup tables will be needed. Within each model, the primaries were quite consistent (despite the age of phone varying within each sample). The worst case in each model was the blue primary; the 95th percentile limits in the v' coordinate were ±0.008 for the iPhone 4 and ±0.004 for the other three models. The u'v' variation in white points was ±0.004 for the iPhone4 and ±0.002 for the others, although the spread of white points between models was u'v'±0.007. The differences are essentially the same for primaries at low luminance. The variation of colors intermediate between the primaries (e.g., red-purple, orange) mirror the variation in the primaries. The variation in luminance (maximum brightness) was ±7%, 15%, 7%, and 15%, respectively. The iPhones have almost 2× the luminance. To accommodate differences between makes and models, dedicated color lookup tables will be necessary, but the variations within a model appear to be small enough that consistent color vision tests can be designed successfully.

Urgent-start peritoneal dialysis: a chance for a new beginning.

Peritoneal dialysis (PD) remains greatly underutilized in the United States despite the widespread preference of home modalities among nephrologists and patients. A hemodialysis-centric model of end-stage renal disease care has perpetuated for decades due to a complex set of factors, including late end-stage renal disease referrals and patients who present to the hospital requiring urgent renal replacement therapy. In such situations, PD rarely is a consideration and patients are dialyzed through a central venous catheter, a practice associated with high infection and mortality rates. Recently, the term urgent-start PD has gained momentum across the nephrology community and has begun to change this status quo. It allows for expedited placement of a PD catheter and initiation of PD therapy within days. Several published case reports, abstracts, and poster presentations at national meetings have documented the initial success of urgent-start PD programs. From a wide experiential base, we discuss the multifaceted issues related to urgent-start PD implementation, methods to overcome barriers to therapy, and the potential impact of this technique to change the existing dialysis paradigm.

Dialysis costs for a health system participating in value-based care.

OBJECTIVES: Unplanned "crash" dialysis starts are associated with worse outcomes and higher costs, a challenging problem for health systems participating in value-based care (VBC). We examined expenditures and utilization associated with these events in a large health system. STUDY DESIGN: Retrospective, single-center study at Cleveland Clinic, a large, integrated health system participating in VBC contracts, including a Medicare accountable care organization. METHODS: We analyzed beneficiaries who transitioned to dialysis between 2017 and 2020. Crash starts involved initiating inpatient hemodialysis (HD) with a central venous catheter (CVC). Optimal starts were initiated with either home dialysis or outpatient HD without a CVC. Suboptimal starts were initiated with outpatient HD with a CVC or inpatient HD without a CVC. RESULTS: A total of 495 patients initiated chronic dialysis: 260 crash starts, 130 optimal starts, and 105 suboptimal starts. Median predialysis 12-month cost was $67,059 for crash starts, $17,891 for optimal starts, and $7633 for suboptimal starts (P < .001). Median postdialysis 12-month cost was $71,992 for crash starts, $55,427 for optimal starts, and $72,032 for suboptimal starts (P = .001). Predialysis inpatient admission per 1000 beneficiaries was 1236 per 1000 for crash starts vs 273 per 1000 for optimal starts and 170 per 1000 for suboptimal starts (P < .001). Postdialysis inpatient admission for crash starts was 853 per 1000 vs 291 per 1000 for optimal starts and 184 per 1000 for suboptimal starts (P < .001). CONCLUSIONS: In a major health system, crash starts demonstrated the highest cost and hospital utilization, a pattern that persisted after dialysis initiation. Developing strategies to promote optimal starts will improve VBC contract performance.

Quality of resident violence risk assessments in psychiatric emergency settings.

OBJECTIVE: To identify how psychiatric residents perceive their ability to conduct violence risk assessments and the risk factors they considered relevant in an emergency department setting. METHOD: We surveyed 55 of 159 psychiatric residents at the University of Toronto as to their experience and education in assessing suicide and violence risk. The residents, and a comparison group of 11 of 16 staff psychiatrists in the Law and Mental Health program at the Centre for Addiction and Mental Health, then participated in a mock interview with one of the authors. The subjects were directed to ask for all risk factors that would be relevant in determining the violence risk of a hypothetical patient with homicidal ideation. The risk factors they requested were compared with the risk factors found in the Historical, Clinical and Risk Management-20 (HCR-20) structured clinical judgment tool. RESULTS: Psychiatric residents, on average, inquired about 6 fewer HCR-20 risk factors than staff psychiatrists (8.5, compared with 14.7). The number of HCR-20 items identified by residents correlated with several items; more risk factors were elicited by residents in a higher year of training, those who had received more formal and informal education, the number of patients for whom they had discharged a duty to warn, and the number of suicidal and violent patients they had previously assessed. Confidence at assessing violence risk was not correlated with performance. CONCLUSIONS: Psychiatric residents identify significantly fewer risk factors for violence than staff psychiatrists. Resident performance was correlated with increasing experience and education. It was not related to self-confidence in performing this task.

Moving from Evidence to Implementation of Breakthrough Therapies for Diabetic Kidney Disease.

Diabetic kidney disease is the most frequent cause of kidney failure, accounting for half of all cases worldwide. Moreover, deaths from diabetic kidney disease increased 106% between 1990 and 2013, with most attributed to cardiovascular disease. Recommended screening and monitoring for diabetic kidney disease are conducted in less than half of patients with diabetes. Standard-of-care treatment with an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker is correspondingly low. Sodium-glucose cotransporter 2 inhibitors, glucagon-like peptide 1 receptor agonists, and a nonsteroidal mineralocorticoid antagonist are highly effective therapies to reduce kidney and cardiovascular risks in diabetic kidney disease. However, <20% of eligible patients are receiving these agents. Critical barriers are high out-of-pocket drug costs and low reimbursement rates. Data demonstrating clinical and cost-effectiveness of diabetic kidney disease care are needed to garner payer and health care system support. The pharmaceutical industry should collaborate on value-based care by increasing access through affordable drug prices. Additionally, multidisciplinary models and communication technologies tailored to individual health care systems are needed to support optimal diabetic kidney disease care. Community outreach efforts are also central to make care accessible and equitable. Finally, it is imperative that patient preferences and priorities shape implementation strategies. Access to care and implementation of breakthrough therapies for diabetic kidney disease can save millions of lives by preventing kidney failure, cardiovascular events, and premature death. Coalitions composed of patients, families, community groups, health care professionals, health care systems, federal agencies, and payers are essential to develop collaborative models that successfully address this major public health challenge.

Real-world effectiveness of repeated ketamine infusions for treatment resistant depression during the COVID-19 pandemic.

Herein we evaluate the impact of COVID-19 restrictions on antidepressant effectiveness of intravenous (IV) ketamine in adults with treatment-resistant depression (TRD). We conducted a case series analysis of adults with TRD (n = 267) who received four ketamine infusions at an outpatient clinic in Ontario, Canada, during COVID-19 restrictions (from March 2020 - February 2021; n = 107), compared to patients who received treatment in the previous year (March 2019 - February 2020; n = 160). Both groups experienced significant and comparable improvements in depressive symptoms, suicidal ideation, and anxiety with repeated ketamine infusions. Effectiveness of IV ketamine was not attenuated during the COVID-19 period.

Buttonhole Cannulation of Arteriovenous Fistulas in the United States.

The cannulation technique of a hemodialysis vascular access has remained controversial with differing viewpoints. The quality of dialysis, overall patient safety, and individual dialysis experience often dictate the type of cannulation technique used in clinical practice. The three commonly used techniques to access a hemodialysis vascular access are the rope ladder, area, and buttonhole. Although the buttonhole technique has been around since the mid-1970s, the dialysis community remains divided on its suitability for routine use to provide maintenance hemodialysis therapy. The proponents of this technique value the ease of cannulation with less pain and discomfort whereas the opponents highlight the increased risk of infection. The actual clinical evidence from the United States is limited and remains inconclusive. The current review provides an overview of the available experience from the United States, highlighting the correct technique of creating a buttonhole, summarizing the current evidence, and recommending a need for larger randomized controlled studies in both in-center and home hemodialysis populations.

The financial implications for Medicare of greater use of peritoneal dialysis.

BACKGROUND: Although annual per-person health care costs for patients with end-stage renal disease (ESRD) on in-center hemodialysis greatly exceed those for patients on peritoneal dialysis (PD), which is a home dialysis therapy, current use of PD remains low. In April 2008, the Centers for Medicare & Medicaid Services issued a new Dialysis Conditions of Coverage final rule underscoring its intent to promote use of home dialysis whenever appropriate. OBJECTIVES: The objectives of this paper were to provide context for the use of in-home versus in-center dialysis, to describe factors that influence patterns of dialysis utilization in the United States, and to explore the magnitude of the potential savings that might result from broader use of home dialysis therapies. METHODS: A 5-year budget-impact analysis was performed using data from the 2007 Annual Data Report of the United States Renal Data System. Scenarios were developed in which the PD share of total dialysis was varied to estimate the impact on total Medicare dialysis costs. This study took the perspective of Medicare, the main payer for dialysis in the United States. RESULTS: If the PD share of total dialysis were to decrease from the current 8% to 5%, Medicare spending for dialysis would increase by an additional $401 million over a 5-year period. Alternatively, if the PD share of total dialysis were to increase to 15%, Medicare could realize potential savings of >$1.1 billion over 5 years. CONCLUSIONS: Similar to the conclusion articulated in the Dialysis Conditions of Coverage final rule, increasing clinically appropriate use of PD would be associated with considerable savings to Medicare and to the taxpayers who fund Medicare. These savings could be used to offset part of the financial burden of ESRD care on Medicare and to help legislators meet ever-tightening budgetary constraints.

Severe lactic acidosis associated with juice of the mangosteen fruit Garcinia mangostana.

The tropical mangosteen fruit has long been prized in Southeast Asia for its traditional healing properties. Mangosteen fruit juice is now available in the United States and marketed for its purported health benefits. We describe a case of severe lactic acidosis associated with the use of mangosteen juice as a dietary supplement.

Systems Thinking and Leadership: How Nephrologists Can Transform Dialysis Safety to Prevent Infections.

Infections are the second leading cause of death for patients with ESKD. Despite multiple efforts, nephrologists have been unable to prevent infections in dialysis facilities. The American Society of Nephrology and the Centers for Disease Control and Prevention have partnered to create Nephrologists Transforming Dialysis Safety to promote nephrologist leadership and engagement in efforts to "Target Zero" preventable dialysis infections. Because traditional approaches to infection control and prevention in dialysis facilities have had limited success, Nephrologists Transforming Dialysis Safety is reconceptualizing the problem in the context of the complexity of health care systems and organizational behavior. By identifying different parts of a problem and attempting to understand how these parts interact and produce a result, systems thinking has effectively tackled difficult problems in dynamic settings. The dialysis facility is composed of different physical and human elements that are interconnected and affect not only behavior but also, the existence of a culture of safety that promotes infection prevention. Because dialysis infections result from a complex system of interactions between caregivers, patients, dialysis organizations, and the environment, attempts to address infections by focusing on one element in isolation often fail. Creating a sense of urgency and commitment to eradicating dialysis infections requires leadership and motivational skills. These skills are not taught in the standard nephrology or medical director curriculum. Effective leadership by medical directors and engagement in infection prevention by nephrologists are required to create a culture of safety. It is imperative that nephrologists commit to leadership training and embrace their potential as change agents to prevent infections in dialysis facilities. This paper explores the systemic factors contributing to the ongoing dialysis infection crisis in the United States and the role of nephrologists in instilling a culture of safety in which infections can be anticipated and prevented.

Uremic pericarditis, pericardial effusion, and constrictive pericarditis in end-stage renal disease: Insights and pathophysiology.

A rising prevalence of end-stage renal disease (ESRD) has led to a rise in ESRD-related pericardial syndromes, calling for a better understanding of its pathophysiology, diagnoses, and management. Uremic pericarditis, the most common manifestation of uremic pericardial disease, is a contemporary problem that calls for intensive hemodialysis, anti-inflammatories, and often, drainage of large inflammatory pericardial effusions. Likewise, asymptomatic pericardial effusions can become large and impact the hemodynamics of patients on chronic hemodialysis. Constrictive pericarditis is also well documented in this population, ultimately resulting in pericardiectomy for definitive treatment. The management of pericardial diseases in ESRD patients involves internists, cardiologists, and nephrologists. Current guidelines lack clarity with respect to the management of pericardial processes in the ESRD population. Our review aims to describe the etiology, classification, clinical manifestations, diagnostic imaging tools, and treatment options of pericardial diseases in this population.

The Use of a Multidimensional Measure of Dialysis Adequacy-Moving beyond Small Solute Kinetics.

Urea removal has become a key measure of the intensity of dialysis treatment for kidney failure. Small solute removal, exemplified by Kt/Vurea, has been broadly applied as a means to quantify the dose of thrice weekly hemodialysis. Yet, the reliance on small solute clearances alone as a measure of dialysis adequacy fails fully to quantify the intended clinical effects of dialysis therapy. This review aims to (1) understand the strengths and limitations of small solute kinetics as a surrogate marker of dialysis dose, and (2) present the prospect of a more comprehensive construct for dialysis dose, one that considers more broadly the goals of ESRD care to maximize both quality of life and survival. On behalf of the American Society of Nephrology Dialysis Advisory Group, we propose the need to ascertain the validity and utility of a multidimensional measure that moves beyond small solute kinetics alone to quantify optimal dialysis derived from both patient-reported and comprehensive clinical and dialysis-related measures.

Fatigue Damage Monitoring of a Composite Step Lap Joint Using Distributed Optical Fibre Sensors.

Over the past few decades, there has been a considerable interest in the use of distributed optical fibre sensors (DOFS) for structural health monitoring of composite structures. In aerospace-related work, health monitoring of the adhesive joints of composites has become more significant, as they can suffer from cracking and delamination, which can have a significant impact on the integrity of the joint. In this paper, a swept-wavelength interferometry (SWI) based DOFS technique is used to monitor the fatigue in a flush step lap joint composite structure. The presented results will show the potential application of distributed optical fibre sensor for damage detection, as well as monitoring the fatigue crack growth along the bondline of a step lap joint composite structure. The results confirmed that a distributed optical fibre sensor is able to enhance the detection of localised damage in a structure.