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S Andrulli

Publications and source records attributed to S Andrulli.

44 records · Page 3Linked to original sources
PubMedDate not supplied

Survival of prosthetic grafts of different materials after impairment of a native arteriovenous fistula in hemodialysis patients.

In our department, hemodialysis vascular accesses with graft, are used in patients with impairment of native distal and proximal arteriovenous fistulas (AVF-E). The aim of this study was to compare the survival of grafts of different materials (PTFE vs. bovine vein) in these patients. From 1991 to 1999, we prospectively evaluated 53 patients (35 women, 18 men, age 68 +/- 11 years, on dialysis for 70 +/- 65 months). Fifty-three PTFE, 10 reinforced PTFE, and 22 bovine vein grafts were placed. We evaluated the primary patency (PP) (days between fistula placement and the last dialysis before thrombosis occurred) and the secondary patency (SP) (days between fistula placement and the last dialysis treatment before it was considered lost) by separating PTFE survival from that of bovine veins. In the same patients, we also evaluated the survival of the native arteriovenous fistulas (AVF-E) during the pregraft period. Furthermore, we evaluated 404 patients (172 women, 232 men, age 65 +/- 14 years, on dialysis for 50 +/- 53 months) in whom only AVF-E were placed during the same follow-up period. Graft and AVF-E survival were calculated according to the Kaplan-Meier method. In patients with grafts, the PP at 1 year was 17.4% for PTFE and 23.9% for bovine veins. At 12 months, the SP of bovine veins was significantly higher than that of PTFE (81,9% vs. 50%, p < 0.04). In the patients who only had AVF-E, the PP and SP was, respectively, 43% at 12 months and 52.4% at 50 months. A preliminary experience in 22 patients with a 20 month follow-up confirms better survival of bovine veins than PTFE (p < 0.04).

Aged↗
PubMedDate not supplied

Combined treatment with steroids and azathioprine in IgA nephropathy: design of a prospective randomised multicentre trial.

Corticosteroids have had variable success in IgA nephropathy (IgAN). Our previous trial with a six-month course of steroids in IgAN patients showed they were effective in reducing the risk of renal function deterioration and proteinuria, but this effect seemed to decrease in the long term. This new randomised trial was designed to prospectively evaluate whether adding low-dose azathioprine to steroids improves long-term renal survival in adult biopsy-proven IgAN patients with proteinuria > or = 1 g/24 h and plasma creatinine < or = 2.0 mg/dl. The patients will be treated with steroids (methylprednisolone 1 g i.v. for three consecutive days at months 1, 3 and 5, plus oral prednisone 0.5 mg/kg every other day for six months) plus azathioprine 1.5 mg/kg/day for six months or steroids alone with the same schedule. Altogether a minimum of 346 patients should be enrolled within a four-year recruitment period. The planned duration of follow-up is five years.

Adolescent↗
PubMedDate not supplied

Effect of sodium pool changes on blood pressure in patients undergoing PFD: design of a prospective randomized multicenter trial.

Blood pressure control is important during dialysis and the interdialytic period because of the frequency and potential seriousness of hypotension and hypertension. Water and sodium removal play an important role in the genesis of intradialytic cardiovascular instability or hypertension. Changing dialysate sodium concentrations without the aid of a kinetic model can sometimes give good results but is only an empirical approach. Therefore, this clinical trial was designed to prospectively investigate the advantages of changes in the sodium pool on the blood pressure profile of patients undergoing paired filtration dialysis (PFD). The hypothesis to be tested is whether using a dialysate conductivity which, according to the conductivity kinetic model, ensures that the conductivity of the ultrafiltrate at the end of each dialysis session is 0.3 mS/cm more (B) or less (C) than the mean during the run-in period, improves blood pressure control either in patients prone to intradialytic hypotension or patients who are hypertensive or normotensive with antihypertensive treatment. Patients will be randomly allocated to one of two treatment sequences (where treatment A is standard PFD): AABB or ABAA for patients with intradialytic hypotension; AACC or ACAA for hypertensive patients. During the experimental phase arterial blood pressure will be measured and symptoms reported by the patients will be recorded.

Blood Pressure↗
PubMedDate not supplied

Evaluation of dialysis outcomes: experimental versus observational evidence.

Evidence-based medicine provides tools to evaluate dialysis outcomes by integrating knowledge obtained from interventional and observational studies. This is illustrated in relation to three important topics: dialysis membranes, dialysis dose and anemia. Clinical trials and observational evidence support each other in indicating a decrease in dialysis-related amyloidosis morbidity when high-flux dialysis is used, whereas the impact of dialysis membranes on mortality is still controversial. Two clinical trials are currently investigating this issue: the American Hemodialysis (HEMO) Study and the European Membrane Permeability and ESRD Patient Outcome (MPO) Study. As indicated by the National Cooperative Dialysis Study (NCDS), dialysis dose is an important determinant of patient outcome. Although Gotch's analysis of the NCDS showed no further benefits for Kt/V>0.9, the analysis by Keshaviah showed a progressive benefit as Kt/V increased beyond 0.9. This finding has been confirmed by observational studies, of which the Dialysis Outcome and Practice Patterns Study (DOPPS) is the most recent and interesting. Further information is also expected from the HEMO study. The findings of observational and interventional studies are consistent in indicating anemia as a major determinant of morbidity and mortality in dialysis patients. American and European guidelines advise hemoglobin levels of 11-12 g/dl and hematocrit levels of 33-36%. The real benefit of completely correcting anemia is not so clear. In conclusion, far from being in opposition, clinical trials and observational studies can provide an integrated contribution to the analysis of dialysis outcomes.

Anemia↗
PubMedDate not supplied

[Water quality cuts down the chronic inflammatory risk: how to obtain it and keep it over time].

BACKGROUND: Every week, approximately 400 liters of water used for dialysate production come into direct contact, through the semi-permeable membrane of the dialyzer, with the dialysis patient's blood stream. Therefore, submitting municipal water to an adequate depuration process before its use for dialysis becomes necessary. METHODS: Problems related to the implementation, updating and management of a dialysis water treatment system are analyzed. The results of the most recent multicenter studies on dialysis fluids quality are also reviewed. RESULTS: The best approach to plan, implement and manage a dialysis water treatment system, first, consists of defining the standards of chemical and microbiological water quality. The most diffused and commonly accepted standards are those recommended by the Association for Advancement of Medical Instrumentation (AAMI) and the European Pharmacopea (EP), which allow a maximum bacterial growth of, respectively, 200 CFU/ml and 100 CFU/mL and a maximum endotoxin concentration of 2 IU/mL and 0.25 IU/mL. A modern dialysis water treatment system provides a final purification process, mainly by reverse osmosis (RO), together with different pre-treatment levels and a hydraulic distribution circuit. Therefore, as RO produces water of optimal chemical and microbial quality, all efforts in the dialysis unit must be aimed at keeping this quality as constant as possible over time, by carrying out effective maintenance strategies and system disinfection. Nevertheless, several multicenter studies reported that 7-35% of water samples exceed a bacterial growth of 200 CFU/mL and that 44% of them display endotoxin concentrations >5 IU/mL. CONCLUSIONS: The results of multicenter studies indicate that the microbial quality of dialysis fluids is, unfortunately, still an often neglected problem. Evidence of a possible relationship between dialysis fluid contamination and patient morbidity, as well as the availability of systems and machines allowing purity levels that were unimaginable only a few years ago, must be a stimulus for modifying clinical practices and starting the improvement processes aimed at maximally reducing the risk of microbial contamination in the dialysis water, as already done with chemical contamination.

Chronic Disease↗
PubMedDate not supplied

[Clinical relevance of study results].

The critical appraisal process of available evidence includes the evaluation of clinical importance of the study findings. This should coincide with the minimum worthwhile effect expected by the investigators in the study design and planning. In hard outcome studies it can be quantified by the absolute risk difference between groups and its reciprocal, known as number needed to treat to avoid one adverse event, or benefit (NNTB). The number needed to treat to produce harmful consequences of treatment (NNTH) should also be taken into account. Finally these effect measures, like risks and incidence proportions, are usually rough estimates of the true effects, due to non-complete follow-up of the observations under study. Underlying assumptions and design issues are especially important to assess the clinical relevance of any results.

Clinical Trials as Topic↗
PubMedDate not supplied

[P value and confidence intervals: reporting and interpreting the result of a clinical study].

The main purpose of statistics in the analysis of clinical and epidemiological studies is to summarize data and information, as well as assess variability, trying to distinguish between chance findings and results that may be replicated upon repetition. Statistical analyses only convey the effect of chance element in data (random error). Statistics cannot control non-sampling errors concerning study design, conduct and methods adopted. At the end of the study, a result is defined statistically significant if the observed difference in the outcome variable is too large to be attributed to chance. A small P value provides evidence against the null hypothesis (of no effect), since data have been observed that would be unlikely if the null hypothesis was true. However, confidence intervals estimate separate the two data dimensions (strength of the relation between exposure and disease, and precision with which the relation is measured), and add to the hypothesis testing useful information for finding interpretation and further research.

Biomedical Research↗