[Management of central venous catheter: prevention of thrombosis and bacteremia]. / Gestione del catetere venoso centrale: prevenzione della trombosi e della batteriemia.

The use of central venous catheters (CVC) as vascular access has increased considerably in recent years, especially because of the progressive aging and increasingly severe comorbidities of the dialysis population. The main factors limiting the long-term use of a hemodialysis catheter are thrombosis and infection. Thrombosis can be treated with thrombolytic agents and prevented effectively by means of anticoagulants. CVC infections represent the main cause of morbidity and mortality in these patients. This is the reason why systemic antibiotic therapy must be started very rapidly, based even on a simple clinical suspicion and in the absence of any confirmation of bacteremia. If antibiotic therapy fails, the CVC must be removed. The recent introduction of antibiotic lock therapy appears to be an effective means to prevent bacteremia. However, it must not be forgotten that the best way of preventing CVC-related bacteremia is by reinforcing all control procedures, with the active involvement of patients and staff.

[A particular case of hemodialysis with a single-pass batch system]. / Un caso particolare di emodialisi con un single pass batch system.

The GENIUS 90 Therapy System (GENIUS) (Fresenius Medical Care, Bad Homburg, Germany) is a mobile dialysis machine with a 90-liter, thermally insulated glass tank. Fresh dialysis fluid is prepared by mixing sterile ingredients (electrolytes and glucose) with preheated ultrapure water. Here we report the case of a 60-year-old hemodialysis patient who was hospitalized in our unit in November 2005 because of an ischemic stroke affecting the left temporal-parietal-occipital region of the brain. The persisting clinical features included right hemiplegia, motor aphasia, epilepsy and stage I coma. The patient started thrice-weekly GENIUS hemodialysis treatment (about 270 sessions to date) in his hospital room with no continuous nursing assistance. In conclusion, GENIUS is able to offer user-friendly, high-quality and adequate dialysis treatment.

[We should strive for optimal hemodialysis: treatment time is the key factor]. / Dovremmo lottare strenuamente per una emodialisi ottimale: il tempo di trattamento e' il suo fattore chiave.

Nephrologists should strive for optimal hemodialysis. Convection, at least as it is conceived today, is far from optimal and the same is true of standard bicarbonate dialysis. A very recent paper by Eloot et al (Kidney Int 2008: 73: 765-70) clearly illustrates the way towards optimal hemodialysis by showing in a simple and intelligent manner the independent effect of the factor time on the adequacy of hemodialysis. Furthermore, it simplifies the conceptual scenario of dialysis adequacy and points to diffusion mechanisms as the key modality to remove uremic retention solutes. Thus, it is clear that we should strive for longer and/or more frequent dialysis sessions. Long nocturnal home hemodialysis every other night appears to be more appealing to patients than 5 to 7 dialysis sessions a week. The Italian Society of Nephrology should promote trials and the National Health Service should provide funds for these promising hemodialysis schedules.

[Occlusion of hemodialysis vascular accesses by means of endovascular procedures]. / Chiusura degli accessi vascolari per emodialisi con procedure endovascolari.

Correct management of complications is crucial to the long-term survival of vascular access for hemodialysis. The present work report our experience with endovascular procedures in the occlusion of complicated arteriovenous fistulas (AVFs) and grafts in patients with a high surgical risk. Among the endovascular procedures carried out between January 2003 and December 2006, all those regarding the occlusion of vascular accesses by means of embolization or exclusion were selected retrospectively. Embolization means the release into the circulation of material to occlude the vascular lumen; exclusion is obtained by means of covered stents, which, when placed in a blood vessel, exclude its ramifications. Seven procedures of endovascular occlusion of vascular accesses were performed in the study period. All patients were considered as having a high surgical risk or presented technical difficulties related to surgical intervention. Venous hypertension was the indication in 5 cases and grade III or IV steal syndrome was the indication in 2 cases. Six AVFs were treated: 2 distal radiocephalic, 1 brachiocephalic, 2 brachiobasilic, and 1 Gracz AVF; an antebrachial graft was also treated. Occlusion was obtained in 4 cases by means of embolization and in 3 cases by means of exclusion. The technical success was 100% with virtually no complications. Endovascular occlusion of vascular access represents an effective and safe procedure in selected cases, also when compared with the surgical approach. Furthermore, the different technical solutions available allow to adequately solve the problems linked to anatomical variability and to the sites of the vascular accesses.

[Management of arteriovenous fistula: anastomosis and more....]. / Gestione della fistola arterovenosa: l'anastomosi e oltre...

The huge amount of human and economic resources necessary for a vascular access creation in haemodialysis strongly requires a very careful patient assessment and the choice of the most appropriate procedures, both aiming at improving quality of care and optimizing available resources. This review focuses on arteriovenous fistula (AVF) monitoring and surveillance, not only by following current guidelines, but also by exploring the most interesting data of the literature; attention is particularly focused on the haemodynamic aspects of AVF, which play a relevant role not only in himself. the natural history of vascular access, but also of the patient.

A modified Two-BUN method for routine urea modeling: clinical validation in 120 patients on a free diet.

Recently, a modified algorithm of the Two-BUN method (MA2p), avoiding dialyzer clearance measurement, was presented for routine assessment of Kt/V and NPCR. To validate MA2p in patients on a free diet (FDP), we studied 120 stable dialysis FDP by measuring Kt/V and NPCR with both MA2p and a modified version of the standard Three-BUN method (MA3p), for the 3 weekly sessions. The NPCR values (g/kg/day), calculated by MA3p for the 3 interdialyses were: 1.286 +/- 0.274, 1.256 +/- 0.276, and 1.116 +/- 0.230, respectively. The correlation coefficient (r) for averaged Kt/V values obtained by the two methods was 0.999 and the percent error (Error%) for MA2p vs. MA3p results ranged from -1.5 to +0.78%. The respective results for NPCR were: r = 0.967, Error% range from -11.7 to +13.9%. In conclusion, MA2p can be safely used in patients on a free diet. The lowest NPCR values were observed during the long interdialysis.

Chronic glomerulonephritis and exposure to solvents: a case-referent study.

To evaluate the risk of chronic glomerulonephritis in subjects exposed to solvent vapours, a case-referent study was carried out. The case group, including 60 patients (44 men and 16 women) with non-systemic chronic glomerulonephritis, established by biopsy, was compared with 120 control subjects (60 patients with traumatic fractures and 60 patients affected by nephrolithiasis) matched by sex and age. Information on occupational and non-occupational exposure to solvent was obtained by questionnaire. The exposure scores drawn from questionnaires were significantly higher in the case group than in the referent groups for both total and occupational solvent exposure. No significant differences in non-occupational exposure were found. The odds ratio of chronic glomerulonephritis for occupationally exposed (score > 0) was 3.9 (95% confidence interval (95% CI) 1.64-8.33). When IgA nephropathy patients (n = 27) were separately evaluated, an increased risk was found for both total and occupational exposure. Using a logistic regression model, a dose-response effect for occupational exposure was seen. The results support the hypothesis that chronic glomerulonephritis may be related to environmental factors such as exposure to hydrocarbons.