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Arteriovenous fistula (AVF) is still in 2010 the gold standard of vascular(2) access in haemodialysis (HD) patients. Nevertheless it may be difficult to obtain and/or to use AVF in elderly. With this prospective randomised pilot study, we compare two strategies of vascular access in 70 years old or more new HD patients. AVF were compared to tunnelled jugular vein catheters (TIJC) with taurolidine as bacterial lock solution. Results were as follow: [table: see text] The responses with the visual analogic scale of comfort was 8/10 for TIJC and 5/10 with AVF * P<0.05. In five TIJC patients, heparin was added with success to taurolidine because of partial clotting of catheters. Albuminemia was significantly lower in AVF failure patients compared to AVF success patients (24.8g/L vs 31.1g/L). This pilot study allows to conclude that TIJC is an acceptable challenge to AVF in haemodialysed patients of 70 years or more in a two years long use., (Copyright © 2011 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.)

A correct access flow is one of the most important factors for dialysis efficiency. Clinical examination does not allow the detection of flow decrease. We conducted a prospective study comparing the dilution ultrasound system (Transonic) to duplex Doppler sonography (GE logiq 700 expert series) in two phases: Comparison of the access flow values obtained with both devices and discussion of their discrepancies. Scheduled survey of vascular access, analysis of its results regarding the rate of fistula thrombosis, then definition and achievement of a strategy of early preventive surgery. After two years, flow data were similar with both systems, provided that Transonic values were corrected by a constant coefficient. The use of both techniques during the scheduled survey of fistulas resulted in a 43% decrease of the rate of acute thrombosis (p < 0.05).

A simple, safe and potentially cost effective method of giving intravenous iron to patients receiving regular haemodialysis therapy is described. The heparin and iron are mixed in normal saline and given as a continuous infusion via the syringe pump present on the modern dialysis machine. No pharmacological incompatibility was observed between iron polymaltose and Heparin Choay or Heparin Roche. No adverse reactions attributable to i.v. iron were observed in over 400 patients and more than 30,000 dialyses.

Chronic hemodialysis patients often have lesions of the hands characterized by distinctive etiopathogenic mechanisms and functional consequences. We conducted a prospective cross-sectional study in 116 patients with a mean age of 55.9 years and a mean hemodialysis duration of 8.17 years. Carpal tunnel syndrome was present in 28.4% of patients. Median nerve entrapment was bilateral in a large proportion of cases. Wasting of the lateral thenar muscles was often present at diagnosis, denoting advanced nerve compression. Amyloid was demonstrated in the carpal tunnel in 74% of cases of carpal tunnel syndrome. Digital flexor tendon lesions responsible for trigger finger or restriction of active flexion were seen in 21.5% of patients. Erosive arthropathy manifesting as deformities, pain and loss of function affected the distal interphalangeal joints in 11% of patients and the proximal interphalangeal joints or trapeziometacarpal joint in a smaller proportion of patients. Thirty per cent of patients had bony cysts located in the carpometacarpal area, carpal bones, or distal forearm bones; communication with the adjacent joint space was seen occasionally, and intracarpal derangement was a feature in some patients. Most patients had several types of lesions. The rate of occurrence of hand lesions increased markedly after ten years on hemodialysis, with devastating functional consequences.

Due to the incidence of symptomatic atherosclerosis in uremic patients, hemostasis-derived cardiovascular risk factors, basal plasma concentrations of some endothelial-derived glycoproteins and desmopressin-induced variations of endothelial-derived proteins were studied in 22 uremic patients on prolonged maintenance hemodialysis with no cardiovascular antecedent. Compared to control subjects, patients had increased predialysis hemostasis-related cardiovascular risk factors: high fibrinogen, proconvertin, and type 1 plasminogen activator inhibitor plasma concentrations; low albumin values; generally low antithrombin III values but sometimes high. They had high predialysis plasma concentrations of endothelium-derived glycoproteins: von Willebrand factor, tissue-type plasminogen activator and urokinase-type plasminogen activator, which are secreted by endothelial cells, but also soluble thrombomodulin, a marker of endothelial cell injury. The desmopressin-induced release of tissue-type plasminogen activator and of von Willebrand factor were lower than in controls. High fibrinogen, type 1 plasminogen activator inhibitor and low albumin plasma concentrations may be linked to repeated acute phase reactions associated with hemodialysis. Data concerning endothelium-related proteins are concordant with the co-existence of a chronic in vivo endothelial activation and endothelial injury in uremia. This could be linked to the initiation and progression of atherosclerosis.

An outbreak of group G streptococci infection affected 6 patients of an hemodialysis unit. Group G streptococci were isolated from patients and from numerous atmospheric specimens, different parts of two dialysis machines, and two blankets, but from only one nurse on the hospital staff. Typing of group G streptococci by an improved method of DNA fingerprinting showed that the isolates from one patient, the nurse and the two blankets differed from one another. The group G streptococci were probably transmitted to patients by dialysis machines with defective microporous filters. No further case of group G streptococci infection was reported three years later since microporous guard filters were systematically doubled.

We studied hemocompatibility of various blood tubings with C3a anaphylatoxin measurement and comparative electron scanning microscopy. The following tubing materials were tested: polyvinylchloride (PVC) plasticised with phthalate (PVC), pvc plasticised with phthalate coextruded with polyurethane (PIV), and two phthalate-free lines: pvc plasticised with trimellitate coextruded with polyurethane (TRI) and pvc plasticised with LT 360 (LTP). Results of C3a generation rate showed a significant activation by all blood tubings, with a reduced rate with PIV when compared to all others. Electron scanning microscopy showed marked alterations of PIV surface on tubings stored for 6 months. Protein deposits on internal surfaces after dialysis were similar whatever tubing material was tested, but adhesive cell number was greater with TRI when compared to PVC and LTP. Hemocompatibility is unchanged with phthalate-free tubings when compared to phthalate plasticised ones. In contrast with phthalate plasticised PVC there is no beneficial effect of polyurethane coextrusion with trimellitate plasticised PVC in regard to C3a generation.

Recombinant human erythropoietin (EPO) has been used for 4 years in end-stage renal disease patients, administered intravenously 3 times a week. A study was undertaken to determine the optimal way of administration comparing 3 times weekly intravenous EPO to self-administered daily subcutaneous EPO (SADSCEPO). In a first group of 4 patients, we demonstrated that the change from 3 times weekly intravenous EPO to SADSCEPO permitted a dose reduction of 70%. In a second group of 20 patients who started the EPO therapy with the daily subcutaneous route at a median dose of 12 U/kg/day, the hematocrit increased from 20 to 30% in 4 months and remained over 30% in spite of a median dose reduction to 9 U/kg/day. The patients' acceptance of SADSCEPO was good. The mechanism allowing such a dose reduction is unknown. However, the significant reduction in median dosage requirement with the subcutaneous route should allow a greater number of patients to be treated more cost-effectively.

Since the identification of beta 2-microglobulin as a major component of 'dialysis amyloid', concern about its removal by different dialysis methods has been raised. Haemodialysis with regenerated cellulose membranes increases serum beta 2-microglobulin by 10-15%. Serial measurements show a very early increase during cuprophan haemodialysis, the mechanism of which is as yet unknown. After cuprophan haemodialysis, serum values return to the initial pretreatment concentrations by the time of the next haemodialysis. In contrast to regenerated cellulose, dialysis with polycarbonate lowers serum beta 2-microglobulin by 8%, and dialysis with polysulphone by 53%. As opposed to cuprophan, after polysulphone haemodialysis the serum concentrations have not returned to the initial pretreatment levels within 48 h. Comparison of beta 2-microglobulin removal using the same polysulphone membrane for haemodialysis and haemofiltration shows that beta 2-microglobulin is more effectively removed by convection than by diffusion when both treatment modes are matched for blood flow and urea clearance. Therefore, in contrast to haemodialysis with regenerated cellulose membranes, where a transient, intradialytic release of beta 2-microglobulin is induced, significant removal is observed using higher permeable membranes. These findings may have implications for the generation of 'dialysis amyloid'.

Because of the known presence of aluminium oxide in the Redy cartridge and the increased solubility of aluminium (A1) in alkaline solution, an in vitro study was performed to measure the release of A1 from the Redy cartridge and its potential transfer across a dialyser membrane. The use of bicarbonate rinsed Redy cartridges was associated with significant release of A1 and its subsequent transfer across the cellulose acetate membrane. Bicarbonate dialysis with the Redy system is not recommended for maintenance haemodialysis.

The background of this study is the occurrence during acetate hemodialysis (HDA) of arterial hypoxemia associated with well described vasodilatator hemodynamic changes. Our aim was to evaluate the relationship between these 2 phenomena. Eleven patients (7 males, 4 females, mean age 54 years) were compared in a protocol of HDA and bicarbonate hemodialysis (HDB) as regards their cardiac output measured by the dye dilution method, blood gases and respiratory gas measurements made at the bedside. The results show significant hypoxemia with hypocapnia as soon as the 30th minute of HDA and no significant variation of cardiac index. No significant variation of respiratory response was noted. Arterial prostaglandin levels rose significantly higher during HDA (+ 302%) than HDB (+ 163%; 2 alpha less than 0,05). The absence of a correlation between arterial hypoxemia and hemodynamic changes in HDA compared to HDB suggests that the phenomena are not interdependent. The importance of increased thromboxane activation in HDA will require further investigation.