Predicting the glomerular filtration rate in bariatric surgery patients

BACKGROUND/AIMS: Identifying the best method to estimate the glomerular filtration rate (GFR) in bariatric surgery patients has important implications for the clinical care of obese patients and research into the impact of obesity and weight reduction on kidney health. We therefore performed such an analysis in patients before and after surgical weight loss. METHODS: Fasting measured GFR (mGFR) by plasma iohexol clearance before and after bariatric surgery was obtained in 36 severely obese individuals. Estimated GFR was calculated using the Modification of Diet in Renal Disease equation, the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation using serum creatinine only, the CKD-EPI equation using serum cystatin C only and a recently derived equation that uses both serum creatinine and cystatin C (CKD-EPIcreat-cystC) and then compared to mGFR. RESULTS: Participants were primarily middle-aged white females with a mean baseline body mass index of 46 ± 9, serum creatinine of 0.81 ± 0.24 mg/dl and mGFR of 117 ± 40 ml/min. mGFR had a stronger linear relationship with inverse cystatin C before (r = 0.28, p = 0.09) and after (r = 0.38, p = 0.02) surgery compared to the inverse of creatinine (before: r = 0.26, p = 0.13; after: r = 0.11, p = 0.51). mGFR fell by 17 ± 35 ml/min (p = 0.007) following surgery. The CKD-EPIcreat-cystC was unquestionably the best overall performing estimating equation before and after surgery, revealing very little bias and a capacity to estimate mGFR within 30% of its true value over 80% of the time. This was true whether or not mGFR was indexed for body surface area. CONCLUSIONS: In severely obese bariatric surgery patients with normal kidney function, cystatin C is more strongly associated with mGFR than is serum creatinine. The CKD-EPIcreat-cystC equation best predicted mGFR both before and after surgery

Extremal Optimization for Graph Partitioning

Extremal optimization is a new general-purpose method for approximating solutions to hard optimization problems. We study the method in detail by way of the NP-hard graph partitioning problem. We discuss the scaling behavior of extremal optimization, focusing on the convergence of the average run as a function of runtime and system size. The method has a single free parameter, which we determine numerically and justify using a simple argument. Our numerical results demonstrate that on random graphs, extremal optimization maintains consistent accuracy for increasing system sizes, with an approximation error decreasing over runtime roughly as a power law t^(-0.4). On geometrically structured graphs, the scaling of results from the average run suggests that these are far from optimal, with large fluctuations between individual trials. But when only the best runs are considered, results consistent with theoretical arguments are recovered.Comment: 34 pages, RevTex4, 1 table and 20 ps-figures included, related papers available at http://www.physics.emory.edu/faculty/boettcher

A comparison between Asian and Australasia backpackers using cultural consensus analysis

This study tests the differences in the shared understanding of the backpacker cultural domain between two groups: backpackers from Australasia and backpackers from Asian countries. A total of 256 backpackers responded to a questionnaire administered in Kuala Lumpur, Bangkok and Krabi Province (Thailand). Cultural consensus analysis (CCA) guided the data analysis, to identify the shared values and the differences in the backpacker culture of the two groups. The findings revealed that while the two groups share some of the backpacker cultural values, some other values are distinctively different from one another. The study provides the first empirical evidence of the differences in backpacking culture between the two groups using CCA. Based on the study findings, we propose some marketing and managerial implications

Domestic Water Demand During Droughts in Temperate Climates: Synthesising Evidence for an Integrated Framework

In the upcoming years, as the population is growing and ageing, as lifestyle changes create the need for more water and as fewer people live in each household, the UK water sector will have to deal with challenges in the provision of adequate water services. Unless critical action is taken, every area in the UK may face a supply-demand gap by the 2080s. Extreme weather events and variations that alter drought and flood frequency add to these pressures. However, little evidence is available about householders’ response to drought and there are few if any studies incorporating this evidence into models of demand forecasting. The present work lays the groundwork for modelling domestic water demand response under drought conditions in temperate climates. After discussing the current literature on estimating and forecasting domestic water consumption under both ‘normal’ and drought conditions, this paper identifies the limited ability of current domestic demand forecasting techniques to include the many different and evolving factors affecting domestic consumption and it stresses the need for the inclusion of inter and intra household factors as well as water use practices in future demand forecasting models

European Association of Urology/European Society for Paediatric Urology Guidelines on Paediatric Urology:Summary of the 2024 Updates

Background and objective: We present an overview of the 2024 updates for the European Association of Urology (EAU)/European Society for Paediatric Urology (ESPU) guidelines on paediatric urology to offer evidence-based standards for perioperative management, minimally invasive surgery (MIS), hydrocele, congenital lower urinary tract obstruction (CLUTO), trauma/emergencies, and fertility preservation. Methods: A broad literature search was performed for each condition. Recommendations were developed and rated as strong or weak on the basis of the quality of the evidence, the benefit/harm ratio, and potential patient preferences. Key findings and limitations: Recommendations for perioperative management include points related to fasting, premedication, antibiotic prophylaxis, pain control, and thromboprophylaxis in patients requiring general anaesthesia. MIS use is increasing in paediatric urology, with no major differences observed among different MIS approaches. For hydrocele, observation is the initial approach recommended. For persistent cases, treatment varies according to the type of hydrocele. CLUTO cases should be managed in tertiary centres with multidisciplinary expertise in prenatal and postnatal management. Neonatal valve ablation remains the mainstay of treatment, but associated bladder dysfunction requires continuous treatment. Among urological traumas and emergencies, renal trauma is still an important cause of morbidity and mortality. Conservative management has become the standard approach in haemodynamically stable children. Ischaemic priapism is a medical emergency and requires stepwise management. Initial management of nonischaemic priapism is conservative. Fertility preservation in prepubertal children and adolescents has become an increasingly relevant issue owing to the ever-increasing number of cancer survivors receiving gonadotoxic therapies. A major limitation is the scarcity of relevant literature. Conclusions and clinical implications: This summary of the 2024 EAU/ESPU guidelines provides updated guidance for evidence-based management of some paediatric urological conditions. Patient summary: We provide a summary of the updated European Association of Urology/European Society for Paediatric Urology guidelines on paediatric urology. There are recommendations on steps to take before and immediately after surgery, management of hydrocele, congenital lower urinary tract obstruction, and urological trauma/emergencies, as well as preservation of fertility. Recommendations are based on a comprehensive review of recent studies.</p

A nationwide study evaluating indications and outcomes for adrenalectomy in children in the Netherlands

Background: Adrenal tumors are rare in children, with neuroblastoma being most common. Surgery is the preferred treatment option, using either an open or minimally invasive approach. In this study we evaluated the incidence, spread, and perioperative outcomes of adrenalectomies in children in the Netherlands. Methods: Patients treated between 2011 and 2022 were reviewed in this nationwide study across 5 academic hospitals and the national pediatric oncology center. Patient characteristics, perioperative data, and follow-up data were collected. Results: The epidemiologic data of 187 patients and the clinical data of 137 patients were included. Annually, 18–20 adrenalectomies in children are performed, mostly for neuroblastoma (64%), pheochromocytoma (18%), and adrenocortical carcinoma (6%). Open adrenalectomy was performed in 88 patients (64%), transperitoneal laparoscopic adrenalectomy in 39 patients (29%), and posterior retroperitoneoscopic adrenalectomy in 10 patients (7%). There was a significant difference in duration of surgery between these approaches (median 171 minutes [interquartile range, 120–213], 105 minutes [interquartile range, 85–148], and 67 minutes [interquartile range, 53–101], respectively, P &lt; .001). Minimally invasive adrenalectomy was used more frequently in older patients with presumed benign disease. Perioperative complications occurred in 25 patients (18%), and 36 patients (26%) had a postoperative complication, of which 3 were major. Disease recurrence was observed in 32% of patients. Conclusion: Adrenalectomies in children are rare in the Netherlands, especially for non-neuroblastoma tumors, and most surgeons perform less than 1 procedure per year. Open adrenalectomy is usually performed for suspected malignant tumors, whereas minimally invasive approaches are used more selectively.</p

Endoscopic dilatation/incision of primary obstructive megaureter. A systematic review. On behalf of the EAU paediatric urology guidelines panel

Introduction: Historically, ureteral reimplantation (UR) has been the gold standard for treatment of primary obstructive megaureter (POM) with declining renal function, worsening obstruction, or recurrent urinary tract infections. In infants, open surgery with reimplantation of a grossly dilated ureter into a small bladder, can be technically challenging with significant morbidity. Therefore, less invasive endoscopic management such as dilatation or incision of the ureter–vesical junction, has emerged as an alternative to reimplantation during the last decades. Objective: To systematically evaluate the effectivity, safety, and potential benefits of endoscopic treatment (dilatation with or without balloon or incision) of POM in comparison to UR. Study design: A systematic review was conducted. Randomized controlled trials (RCTs), nonrandomized comparative studies (NRSs), and single-arm case series including a minimum of 20 participants and a mean follow-up more than 12 months were eligible for inclusion. Results: Of 504 articles identified, 8 articles including 338 patients were eligible for inclusion (0 RCTs, 1 NRSs, and 7 case series). Age at time of surgery was minimum 15 days to a maximum of 192 months. Indications for endoscopic treatment (ET) included patients with loss of split renal function (&gt;10%) and worsening of hydroureteronephrosis. The studies analysed reported a success rate ranging from 35% to 97%. Success was defined as stabilization of differential renal function without further procedures. A post-operative complication rate of 23–60% was reported (mostly transient haematuria, urinary tract infections and stent migration or intolerance). In 14% of the cases salvage UR following initial ET, was performed due to relapse of symptomatic POM. Conclusion: Endoscopic treatment for persistent or progressive POM in children is a minimally invasive alternative to UR with a long-term modest success rate. Additionally, it can be performed within a wide age span, with equal success rate and complication rates.</p

European Association of Urology-European Society of Paediatric Urology Guidelines on Paediatric Urology:Summary of 2024 Updates. Part II

Background and objective: We present a summary of part II of the 2024 update of the European Association of Urology (EAU)/European Society of Paediatric Urology (ESPU) guidelines on paediatric urology. The summary provides evidence-based standards for management of a number of urological conditions in the paediatric population. The aim is to provide practical recommendations for clinical management of these conditions with a focus on diagnosis, treatment, and follow-up. Methods: For the guidelines update, new and relevant evidence was identified, collated, and appraised via a structured assessment of the literature. Databases searched included Medline, EMBASE, and the Cochrane Libraries. Recommendations in the guidelines were developed by the panel to prioritise clinically important care decisions. The strength of each recommendation was determined according to a balance between desirable and undesirable consequences of alternative management strategies, the quality of the evidence (including the certainty of estimates), and the nature and variability of patient values and preferences. Key findings and limitations: Key recommendations emphasise the importance of thorough diagnosis, treatment, and follow-up for patients with the conditions outlines. The guidelines stress the importance of a multidisciplinary approach to treatment and the importance of shared decision-making with patients and their guardians/caregivers. The summary provides evidence-based standards for management of undescended testes, testicular tumours in prepubertal boys, acute scrotum, hypospadias, congenital penile curvature, urinary tract infections, daytime lower urinary tract conditions, urachal remnants, and transitional urology. Conclusions and clinical implications: Part II of the 2024 EAU/ESPU guidelines provides updated guidance for evidence-based management of a number of paediatric urological conditions, with recommendations designed for effective integration into clinical practice.</p