Access Types

Introduction: hemodialysis is a treatment that helps in the survival of patients with renal failure, through an established cardiopulmonary bypass to carry out blood filtration, as a result, there is a need for a feasible, lasting and effective vascular access. There are two types of vascular access, arteriovenous fistulas, using autogenous veins or prostheses, and venous catheters. The indications for choosing the type of vascular access are related to the characteristics and restriction of use of each patient. Objective: to analyze the epidemiological, demographic and clinical profile of patients undergoing hemodialysis in two reference services in the metropolitan region of São Paulo, Brazil, and compare the clinical-surgical processes with those defined by the Kidney Guidelines disease Outcomes Quality Initiative (KDOQI). Methods: data were collected in two public hospitals, with patients undergoing hemodialysis, through registration forms and medical records, from August to December 2016. The volunteers were informed about the procedures and objectives of the study and, after agreeing, they signed a consent form. The variables age, gender, weight, height, body mass index, hemodialysis time, types of accesses already used , complications related to the accesses and underlying disease were analyzed. Patients with chronic renal failure undergoing hemodialysis of both genders, with no age restriction, were included. Patients not able to perform one of the techniques, arteriovenous fistula or catheter, were excluded . The collected data were compared with the Kidney guidelines disease Outcomes Quality Initiative (KDOQI). Results: a total of 252 individuals were included, of which 182 are patients undergoing reference hospital treatment in the city of São Bernardo do Campo, SP and 70 patients at the State University Hospital Mário Covas, a State reference in the clinical management of patients undergoing hemodialysis care. Conclusion: chronic kidney disease is highly prevalent with progression to end-stage chronic kidney failure (dialysis). The definition of the epidemiological profile of the population undergoing treatment, as well as the journey of venous accesses for hemodialysis (catheters and fistulas), are fundamental for the multidisciplinary team’s learning curve about complications throughout the course of the disease/treatment. Furthermore, the clinical-surgical management of this population is in line with the guidelines of the National Kidney Foundation. The treatment performed in these hemodialysis centers is efficient and in line with what the KDOQI recommends.

Arteriovenous fistulae (AVF) have advantages over arteriovenous grafts (AVG) and central venous catheters (CVC), but whether AVF are associated independently with better survival is unclear. Recent studies showing such a survival benefit did not include early access experience or account for changes in access type over time and did not include data on some important confounders. Reported here are survival rates stratified by the type of access in use up to 3 yr after initiation of hemodialysis among 616 incident patients who were enrolled in the Choices for Healthy Outcomes in Caring for ESRD (CHOICE) Study. A total of 1084 accesses (185 AVF, 296 AVG, 603 CVC) were used for a total of 1381 person-years. At initiation, 409 (66%) patients were using a CVC, 122 (20%) were using an AVG, and 85 (14%) were using an AVF. After 6 mo, 34% were using a CVC, 40% were using an AVG, and 26% were using an AVF. Annual mortality rates were 11.7% for AVF, 14.2% for AVG, and 16.1% for CVC. Adjusted relative hazards (RH) of death compared with AVF were 1.5 (95% confidence interval, 1.0 to 2.2) for CVC and 1.2 (0.8 to 1.8) for AVG. The increased hazards associated with CVC, as compared with AVF, were stronger in men (n = 334; RH = 2.0; P = 0.01) than women (n = 282; RH = 1.0 for CVC; P = 0.92). These results strongly support existing clinical practice guidelines and suggest that the use of venous catheters should be minimized to reduce the frequency of access complications and to improve patient survival, especially among male hemodialysis patients.

There is a growing body of literature on the demographic and socioeconomic distinctions between mobile-only and hybrid Internet users and how the two groups use the Internet differently. However, little is known about why people change their type of Internet access and the impact of this change. Relying on data from two waves of a nationally representative survey conducted in China, this study demonstrates that capital-enhancing Internet activities are positively correlated with the likelihood of switching from mobile-only access to hybrid access and negatively correlated with the likelihood of switching from hybrid access to mobile-only access. In addition, those who switch from mobile to hybrid access subsequently strengthen their capital-enhancing uses, thereby not only amplifying the divide between them and others who remain mobile-only but also creating a positive feedback loop. However, non-capital-enhancing uses, such as gaming, are irrelevant to changes in the type of access. It appears that mobile-only access has become a comparable substitute for computer-based Internet in terms of casual activities. However, for “serious” uses, a device divide still exists.

Data collection libraries play an important role in component-based software development. The collections contained in those libraries (JCF, STL, LEDA, etc.) implement a mathematical model that defines one or more access methods to the elements (access by key, access to the element stored last, etc.). In addition, most of these libraries allow a different, more efficient type of access, which can be direct access (e.g., by means of the position where the element is stored, that is obtained when it is inserted) or sequential access (usually by means of the iterator concept). This type of efficient access presents several risks with respect to criteria such as precision and suitability that are not solved appropriately in the current existing libraries. In this work, we present two design patterns that provide a generic solution to the problem together with their implementation using aspects. The patterns introduce new data types and new operations that provide the libraries with full uniformity and a high extensibility degree. The use ofaspects allows dissociating these types of access and the functionality of the collection, making aspects responsible of the position persistence management, modification monitoring during iterations, etc. The proposal is implemented using AspectJ.

The associations of hemodialysis access type and access satisfaction with health-related quality of life

17 - Access Types and Abstract Data Types

Introducción. La enfermedad renal crónica (ERC) es considerada un problema de salud pública mundial y constituye una pérdida progresiva de la función renal. En el estadio 5, conocido como enfermedad renal crónica terminal, el paciente requiere terapia de reemplazo renal (TRR). Este trabajo se busca plasmar si el tipo de diálisis, el tipo de acceso y el tiempo total de TRR tienen relación con la mortalidad de pacientes con ERC en estadio cinco del hospital II-EsSalud de Huánuco. Métodos. Diseño Observacional, analítico, retrospectivo de casos y controles. Se identificaron 50 casos y 50 controles. Se realizaron análisis estadísticos a través de la prueba de Chi-2, Odds ratio con un nivel de confianza al 95%. Resultados. Se halló la asociación entre la mortalidad y los factores de riesgo estudiados como: el tipo de diálisis [P= 0,012; OR= 3,85 (IC 95%: 1,27 – 11,63)], el tipo de accesos [P= 0,017; OR= 4,04 (IC 95%:1,21- 13,43)] y el tiempo total de TRR [P= 0,037; OR=3,16 (IC 95%:1,03 – 9,68)], y el 67,7% de pacientes fue de sexo masculino. Se observó que se asociaban con mortalidad: la edad del paciente > 75 años, el género masculino, la frecuencia de más de 3 diálisis por semana y el lugar de procedencia. Conclusiones. Existe asociación entre el tipo de diálisis, el tipo de acceso y el tiempo total de TRR con la mortalidad de pacientes con ERC terminal.

Is Minimally Invasive Outpatient Pneumonectomy the Current Standard of Care for Lung Cancer?

In the United States, the use of polytertraflouroethylene (PTFE) graft compared with native arteriovenous fistula (AVF) for haemodialysis vascular access has been increasing despite a greater than twofold higher incidence of thrombosis and infection associated with PTFE grafts. We studied 214 haemodialysis patients with not more than two revisions of their vascular access, to determine whether any relationship exists between the type of haemodialysis vascular access and dialysis dose assessed primarily by urea reduction ratio (per cent reduction in blood urea nitrogen concentration after a dialysis session). Serum albumin concentration was used as a secondary outcome measure of dialysis adequacy. Urea reduction ratio and predialysis serum albumin concentration were measured at onset of study and at 4-week intervals and mean values were calculated for each subject. The 214 patients (118 males, 96 females) included 173 Blacks (81%), 26 Whites (15%), and 15 Hispanics (7%), of mean (+/-SD) age 55.6+/-15.5 years. Of these 214 subjects, 111 (52%) had a native AVF, while 103 (48%) had a PTFE graft. Both mean urea reduction ratio (native AVF=69 +/-6.7% vs PTFE graft=70+/-7.3%; P=0.31), and mean serum albumin concentration (native AVF=4.02+/-0.39 g/dl vs PTFE graft=4+/-0.33 g/dl; P= 0.59) were equivalent in both groups. Separate multiple logistic regression analyses with type of vascular access as one of the independent variables, found no significant relationship between type of vascular access and either a urea reduction ratio > 65% (P= 0.67), or a serum albumin concentration >4g/dl (P=0.89), after adjustment for age of vascular access, access revision, location of access, dialyser urea clearance, length of dialysis treatment, body weight, and age. We conclude that PTFE grafts do not permit delivery of better dialysis than native AVF. The increasing use of PTFE grafts in the United States does not have any clinical justification.

Use of standardized ratios to examine variability in hemodialysis vascular access across facilities

Introduction: Hemodialysis is the most common therapy for final stage of the chronic kidney failure. Vascular access is the link between the patient and the machine and the dialyzer so that hemodialysis can be applied effectively. Although huge technological advances have been made, vascular access is still the weak link in treatment. Aim: The determination of the percentages and the type of vascular access carried by patients undergoing hemodialysis in Attica in a statistically significant examined population. Correlation of quality of life, levels of physical activity, the effect of early referral of patients to a nephrologist. Methods: A non-experimental synchronous study was performed where initially the studied population was selected and then the information regarding the determinant and the disease at a specific time was obtained and conducted in hemodialysis units of the public and private sector of Attica. Questionnaires were used for data collection: a) measuring quality of life, b) measuring fatigue c) measuring restless legs syndrome. The statistical program SPSS 22.0 was used for the analysis. Results: In 63.4% of the examined population, vascular access was created with arteriovenous anastomosis (AFA). More than half of the patients visited early a nephrologist before initial hemodialysis session with a rate of 66.2%. Most of those who had AFA visited a nephrologist early. There was a significant difference in the fatigue score depending on the type of vascular access. In the analysis of the dimensions of the quality-of-life scale, it was found that the type of vascular access and previous vascular accesses are related to dimensions of quality of life. Conclusion: It seems that patients who visited a nephrologist in time before initial hemodialysis session had increased rates of AFA and a better score in terms of quality of life. Fatigue was associated with the type of vascular access. The need for National registry system of vascular access seems to help the scientific community in extracting useful scientific data.

Cauliflower (Brassica oleracea var. botrytis) is an important vegetable crop for human nutrition. We characterized 192 cauliflower accessions from the USDA and IPK genebanks with genotyping by sequencing (GBS). They originated from 26 different countries and represent about 44% of all cauliflower accessions in both genebanks. The analysis of genetic diversity revealed that accessions formed two major groups that represented the two genebanks and were not related to the country of origin. This differentiation was robust with respect to the analysis methods that included principal component analysis, ADMIXTURE and neighbor-joining trees. Genetic diversity was higher in the USDA collection and significant phenotypic differences between the two genebanks were found in three out of six traits investigated. GBS data have a high proportion of missing data, but we observed that the exclusion of single nucleotide polymorphisms (SNPs) with missing data or the imputation of missing SNP alleles produced very similar results. The results indicate that the composition and type of accessions have a strong effect on the structure of genetic diversity of ex situ collections, although regeneration procedures and local adaptation to regeneration conditions may also contribute to a divergence. Fst-based outlier tests of genetic differentiation identified only a small proportion (<1%) of SNPs that are highly differentiated between the two genebanks, which indicates that selection during seed regeneration is not a major cause of differentiation between genebanks. Seed regeneration procedures of both genebanks do not result in different levels of genetic drift and loss of genetic variation. We therefore conclude that the composition and type of accessions mainly influence the level of genetic diversity and explain the strong genetic differentiation between the two ex situ collections. In summary, GBS is a useful method for characterizing genetic diversity in cauliflower genebank material and our results suggest that it may be useful to incorporate routine genotyping into accession management and seed regeneration to monitor the diversity present in ex situ collections and to reduce the loss of genetic diversity during seed regeneration.

A requirement of many computer file processing systems is the ability to access data stored on a direct access storage device (DASD) both sequentially and randomly. A popular method which provides both types of access is the index sequential organization. The purpose of this study is to propose and analyze a file organization method which should be appropriate for the same type of environment as index sequential but would be more efficient at the two types of access. This proposed method is designated the Algorithm Sequential Access Method (ASAM).

Patency of Endovascular Treatment for Central Venous Stenosis: Is There a Difference Between Dialysis Fistulas and Grafts?

Factors Associated with Peripheral Blood Stem Cell Yield in Volunteer Donors Mobilized with Granulocyte Colony-Stimulating Factors: The Impact of Donor Characteristics and Procedural Settings