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Background: The goal of haemodialysis treatment in end-stage renal disease (ESRD) patients is to correct the complications of the uraemic condition. Among the main complications are fluid overload and subsequent hypertension that are corrected by achievement of 'dry weight'. We report in this study the evolution of post-dialysis body-weight and blood pressure in patients who began their HD treatment in our unit. [ABSTRACT FROM PUBLISHER]

High blood pressure (BP) is a major factor contributing to the high incidence of cardiovascular morbidity and mortality in haemodialysis (HD) patients. According to predialysis casual BP measurements, long HD has been shown to provide good BP control. To confirm this result during the period between dialysis sessions, we performed ambulatory monitoring of BP in 91 non-selected HD patients (mean age, 58.7 (14.1) years; 14% incidence of nephrosclerosis and diabetes mellitus; treatment duration, 93.0 (77.2) months; 3×8 h/week, cuprophane, acetate buffer in 95% of the patients). Only one patient (1.1%) was receiving an antihypertensive medication. Ambulatory BP results were systolic (S) BP, 119.4 (19.9) mmHg; diastolic (D) BP, 70.6 (12.9) mmHg; mean (M) BP, 87.6 (13.9) mmHg. These values were significantly lower than the casual predialysis BP data and close to the reference values reported by Staessen . in a meta-analysis including 3476 normotensive subjects. The MBP was inversely correlated with the treatment duration, but not with interdialysis weight gain. The MBP increased significantly in the last part of the interdialysis period, and this rise was not correlated with the interdialysis weight gain. The nocturnal/diurnal ratios for SBP and DBP for the HD patients (0.97 and 0.92) were higher than the reference values reported by Staessen, (0.87 and 0.83), and argued against a nocturnal decrease in BP. We found that 52.1% of the patients had an abnormal nocturnal BP fall (MBP fall <5%). This feature worsened during the second night of the interdialysis period. We confirm that interdialysis BP in HD patients treated by long HD and without antihypertensive drugs approached the levels observed in a normal population. Achievement of dry weight is thought to be the cornerstone of this good result, but we cannot rule out other mechanisms such as the optimal clearance of pressor molecules. The BP rise during the interdialysis period, independent of the weight gain, argues for such an accumulation. Despite good BP control the circadian rhythm of BP is not restored in our patients, and remains to be studied. [ABSTRACT FROM PUBLISHER]

Sixty-six haemodialysed (HD) in centre patients (24 h/m/week, acetate bath, cuprophane membrane), with a mean age of 59.2 years, treated for 16.7 ± 4.5 years, underwent clinical examination of their hands to determine anatomical and functional alterations. For each hand a functional score was calculated from a medicolegal technique based on sensitivity and angulation amplitude (rating from 0 to 100). Dialysis-related arthropathy (DRA), including carpal-tunnel (CT) syndrome, was scored as well as hand muscle amyotrophia. Trigger fingers, abnormal synovial hypertrophy, and one or more non-functional tendons were found in 15, 26, and 33% of the patients respectively. Thirteen percent had pseudoporphyria. Amyotrophy was moderate or severe in 39%. The global functional score (mean of the two unilateral functional scores) decreased with time spent on haemodialysis and was correlated with the DRA score. The unilateral functional score was linked to tendinous lesions, amyotrophy, and presence of pulses, but not to CT surgery or presence of AV fistula. Hands with ulnar insult at the elbow shown by electromyography had significantly lower functional scores. Repercussions of hand functional alteration may have an important social and psychological impact in daily life. The responsibility of amyloidosis is evidenced by tendinous lesions and nervous entrapment. Ulnar palsy is also important because of the vital motor role of that nerve in hand function. [ABSTRACT FROM PUBLISHER]

Calciphylaxis (CPX) or calcific uraemic arteriolopathy is a rare life-threatening complication, affecting mainly dialysis patients. The condition is characterized by calcifications and thrombosis of the small cutaneous vessels and small vessels in the fat tissue, resulting in the development of necrotizing and non-healing ulcers. The development of these lesions leads to poor outcomes owing to infectious complications and some frequently associated unfavourable medical conditions: obesity, diabetes, and peripheral vascular disease. We report the case of six patients with different clinical forms of CPX in the past 10 years with favourable outcomes observed in five of the six patients. The diagnosis was based on clinical presentation: bilateral and hyperalgesic necrotic lesions along with a history of mineral metabolism disorder or warfarin use. The therapeutic strategy included the following: daily dialysis, hyperbaric oxygen therapy, treatment of limb artery stenosis, maintenance of the optimal haemodynamic stability, delivery of cutaneous care, administration of analgesics and antibiotics, warfarin and calcium cessation, and additional therapy with cinacalcet or parathyroidectomy and therapy with bisphosphonates or sodium thiosulphate. Healing was observed in five out of six CPX patients by using this strategy that should be rapidly employed in order to decrease the necrotizing areas that result in poor outcomes. Prevention includes identification of at-risk patients in order to optimize the treatment of the identified risk factors for CPX., (Copyright © 2010 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.)

Introduction: The treatment of secondary hyperparathyroidism (SHPT) in dialysis patients has changed with the introduction of cinacalcet (CC), which represents a medical alternative to surgical parathyroidectomy (PTX). The aim of our study is to prospectively assess the tolerance and efficacy of CC in patients, treated in one centre using long haemodialysis, with SHPT who do not respond to conventional therapy., Patients and Methods: We prospectively observed all patients treated with CC between September 2004 and 2009. The characteristics of the patients were compared with that recorded for the patients non treated with CC. Biological factors and the efficacy of the treatment in the patients were compared before (T-0) and after (T-End) CC therapy. The haemodialysis (HD) schedule was 3 x 5 to 3 x 8 h per week. The biological criteria for CC prescription were a serum PTH level greater than 300 pg/ml, calcium level greater than 2.45 mmol/l and bone alkaline phosphatase level greater than 20 microg/l or, in cases of tertiary hyperparathyroidism (THPT), a calcium level greater than 2.55 mmol/l., Results: Eighty-one (14.7%) among the 550 HD patients were treated with CC. As compared to the untreated population, these patients were younger and had higher body mass index (BMI) and higher protein-catabolic rate (nPCR). The treatment failed in 6.1% of the treated patients; 12.3% had severe gastrointestinal side effects and 10% underwent PTX. The treatment was successful in 81.4% patients who were prescribed a mean final CC dosage of 51+/-30 mg/day. Between T-0 and T-End (18+/-15) months), the serum PTH levels decreased by 77%, calcaemia levels decreased by 10% and phosphataemia levels decreased by 14%. Therefore, the percentage of patients with normal biological parameters increased significantly : serum PTH (150-300 pg/ml: 0 to 50%), calcaemia (2.1-2.37 mmol/l: 6 to 77%) and phosphataemia (1.15-1.78 mol/l: 58 to 84%). After 12 months, eight patients (10%) successfully weaned from CC therapy. No episodes of hypocalcaemia (<2.0 mmol/l) occurred. Treatments with alfacalcidol (68 to 40%) and sevelamer (72 to 50%) decreased, treatments with CaCO(3) remained stable (20%), those with native vitamin D increased (55 to 95%)., Conclusion: The treatment of HD patients having SHPT and THPT with CC and vitamin D derivatives was efficacious and well tolerated in a majority of cases after the failure of conventional therapies. These treatments improved mineral metabolism significantly., (Copyright 2010 Association Société de néphrologie. Published by Elsevier SAS. All rights reserved.)

In hemodialysis (HD) patients, mineral metabolism (MM) disorders have been associated with an increased mortality rate. We report the evolution of MM parameters in a stable HD population undergoing long hemodialysis by performing an annual cross-sectional analysis for every year from 1994 to 2008. The therapeutic strategy has changed: the dialysate calcium concentration has decreased from a mean of 1.7 +/- 0.1 to 1.5 +/- 0.07 mmol/L and has been adapted to parathyroid hormone serum levels (from 1 to 1.75 mmol/L). The use of calcium-based and aluminum-based phosphate binders has decreased and they have been replaced by sevelamer; alfacalcidol has partly been replaced by native vitamin D. The percentage of patients with a parathyroid hormone serum level between 150 and 300 pg/mL has increased from 9% to 67% (P<0.001); the percentage of patients with phosphataemia between 1.15 and 1.78 mmol/L has increased from 39% to 84% (P<0.001). The percentage of those with albumin-corrected calcemia between 2.1 and 2.37 mmol/L has increased from 29% to 61% (P<0.001), and that of patients with a calcium-phosphorous product (Ca x P) level >4.4 mmol/L decreased from 8.8% to 2% (P=0.02). Although patients undergo long and intensive HD treatment, MM disorders are common. However, an appropriate strategy, mostly consisting of native vitamin D supplementation, progressive replacement of calcium-based phosphate binders with non-calcium-based ones, and individualization of dialysis session duration and dialysate calcium concentration, would result in a drastic improvement.

Introduction: Catheter-related adverse events (CAE) remain a major cause of mortality and morbidity., Aim: We aimed to compare the CAE prevalence and adverse events rate at 10 years interval in one centre using different devices, dressing procedures., Methods: We compared two periods, from 1994 to 1997 (period 1) and from 2004 to 2007 (period 2). We recorded all prevalent tunnelled CAE and their related adverse event rate: catheter-related bacteraemia (CRB), catheter local infection (CLI), catheter dysfunction leading to CAE exchange, thrombolytic use and spontaneous pulling up., Results: In period 1, PermCath catheter (Quinton, N=63) and TwinCath catheter (MedComp, N=76) were used in 95 HD. BioFlex catheter (N=52) and ASPC split catheter (MedComp, N=52) were used in 72 HD in period 2. In period 1, we performed catheter dressing using povidone iodine versus alcoholic chlorexidine in period 2. Between period 1 and period 2, the CAE prevalence decreased from 15-18% to 9-6%, CRB from 1.1 to 0.23/1000 day-catheter (p<0.001), CLI from 1.1 to 0.28/1000 day-catheter (p<0.001), definitive dysfunction from 12 to 1.2% (p<0.001) and CAE pulling up from 4 to 0%. The annual urokinase consumption decreased from three to one unit per CAE., Conclusion: This study shows the dramatic decrease in CAE prevalence (-50%) and related-adverse events (approximately -200%) since 10 years. Switching povidone iodine to chlorexidine and using more recent catheter devices appear very efficient in decreasing catheter-related adverse events.

Background: Vascular calcifications (VCs) are frequently observed in chronic kidney disease (CKD) and haemodialysis (HD) patients. They have been associated with numerous factors, particularly hyperphosphataemia, excess calcium load, hypertension and increased mortality rate. The purpose of this study is to measure VCs in long-HD patients with good blood pressure and phosphate control, with the occasional use of sevelamer, using a plain radiological score to identify the associated factors and effects on the 1-year survival rate., Methods: We studied HD patients from one centre using a semi-quantitative score ranging from 0 to 3 according to the severity and extent of VCs. The following patients' characteristics were compared according to their VC scores: medical history, treatments, blood pressure, standard biological data, fibroblast growth factor (FGF) 23, osteoprotegerin (OPG), whole PTH, beta-crosslaps, bone alkaline phosphatases and bone mineral density scores. One-year survival analyses were also performed., Results: Among the 250 HD patients of the centre, 161 were studied; the mean age was 67.2 +/- 13 years, 45% of the subjects were females, 35% were diabetics, and they had been on dialysis for between 1-486 months (median: 45 months) with a 3 x 5-3 x 8 h dialysis schedule using 1.5 mmol/l dialysate calcium and providing a mean 2.25 +/- 0.5 Kt/V. Only 17% of the patients were free from VCs and 11% had severe VCs. The factors associated with VCs were classified into 'classic' (age, diabetes, male gender, tobacco use, inflammation, more frequent warfarin treatment and peripheral vascular and cardiac diseases) and 'non-traditional' (higher FGF-23 and OPG serum levels, low albumin serum levels and low alfacalcidol and CaCO(3) use). In logistic regression, only age, diabetes and FGF-23 serum levels were associated with VC scores of 2 and 3. The patients with a score of 3 had a higher 1-year mortality rate (RR 2.1; P = 0.01) as compared to patients with a 0 score., Conclusion: A plain radiological score showed the high prevalence (83%) of VCs in HD patients in spite of a long and intensive dialysis strategy and adherence to guidelines. The main associated factors were classic factors such as ageing and diabetes. No relationship was found with blood pressure and phosphataemia that remained well controlled in long dialysis; the association with FGF-23 serum levels may aggregate some non-traditional risk factors. The harmful effects of VCs on survival require their systematic assessment and optimization of the potentially modifiable associated factors in CKD and HD patients.

Background: In hemodialysis (HD) patients, the plasma brain natriuretic peptide (BNP) level is associated with left ventricular dysfunction and patients' survival. Malnutrition is common in HD patients, it is associated with inflammation and contributes to the high incidence of cardiovascular (CV) disease in this setting (malnutrition-inflammation-atherosclerosis syndrome). In a cross-sectional study, we assessed the relationship between predialysis plasma BNP level and nutritional markers in chronic HD patients., Methods: Of 210 patients receiving HD treatment in our unit, 51 patients who were treated with three times weekly long-hour HD (5-8 h/session) for at least 6 months (mean age 65.8 +/- 15.0 years; F/M ratio 23/28; vintage 71.3 +/- 71.9 months; BMI 24.9 +/- 5.9; session time 6.9 +/- 1.3 h; percentage of diabetic patients 31%) were studied before a mid-week HD session for nutritional markers (plasma albumin 35.3 +/- 3.7 g/l; prealbumin 0.36 +/- 0.09 g/l; CRP 15.3 +/- 14.7 mg/l; nPNA 1.29 +/- 0.29 g/kg/day) and plasma BNP (246.9 +/- 252.2 ng/l, normal <100 ng/l, Bayer(R) kit). The interdialytic weight gain was 2.1 +/- 1.0 kg. In the last 3 months prior to the commencement of the study, the patients' dry weight varied by +0.17 +/- 1.9 kg., Results: Predialysis plasma BNP levels did not differ according to gender and the presence of diabetes. It was not correlated with age and vintage but was found to be negatively associated with the session time (r = -0.34, p = 0.018). Several nutritional markers were negatively correlated with BNP levels: prealbumin (r = -0.46, p = 0.001), BMI (r = -0.33, p = 0.018), nPNA (r = -0.46, p = 0.002). The plasma albumin relationship with the BNP level was close to significance (p = -0.26, p = 0.070). The 3-month dry weight variation was also negatively correlated with BNP levels (r = -0.34, p = 0.018). With multiple stepwise regression analysis, prealbumin and session time remained significant (respectively p = 0.004 and 0.01). BNP levels were higher in a subgroup of malnourished patients (n = 12) (400 +/- 405 vs. 202 +/- 166 ng/l, p = 0.03) than in patients who did not meet the malnutrition criteria (34 patients). They were not correlated with CRP levels, interdialytic weight gain, or predialysis MAP., Conclusions: Hence, the plasma BNP level was found to be associated with malnutrition but not with inflammation. This underlines the relationship between nutrition and the CV system in HD patients. The body weight variations associated with malnutrition and the difficulties in assessing and adjusting dry weight may lead to fluid overload, which could explain, in part, these correlations., (Copyright 2009 S. Karger AG, Basel.)

Progressive nutritional impairment has been recently reported during conventional hemodialysis (HD) treatment. We studied the nutritional parameters during a 5-year follow-up in HD patients. Thirty-three patients (15F/18M; 65 years old at the study start) filled out a 3-day food questionnaire once a year between 1995 and 1999 (study group). Twenty patients, who did not fill out the food records during this period served as a control group (control group). The food record was run by the renal dietician using a dedicated software, providing daily energy and protein intakes (DEI and DPI). Serum albumin, normalized protein equivalent of nitrogen appearance (nPNA), and postdialysis body weight (BW) at the time of food record were collected in the study group and from the patient chart in the control group. The energy intake in the study group and the protein intake in both groups were close to the recommended intakes in ESRD patients. Protein intake assessed from food questionnaire or from urea kinetics were not statistically different. Using ANOVA for repeated measures, no difference along the 5 years was found for daily energy intake, daily protein intake, nPNA, and BW in the study group. The BW and nPNA remained stable in the control group. Hence, this study does not confirm the progressive nutritional impairment reported in the HEMO study, whereas the patients' age and vintage are largely higher in the present study. The role of a large dialysis dose in maintaining nutritional status in HD patients is discussed.

The total amount of sodium present in the body conditions the extracellular compartment volume. In advanced renal failure and in dialysis the sodium balance becomes positive and the extracellular volume inflates. This leads to hypertension and to direct cardiac and vascular changes that explain for a large part the excessive cardiovascular morbidity and mortality in dialysis patients. Controlling body sodium content and extracellular volume allows to reduce hypertension, cardiovascular changes and to improve dialysis patients survival. This can be achieved by reducing the sodium input (low sodium diet and reasonably low sodium dialysate) and/or by increasing sodium output (ultrafiltration by convection in hemodialysis or hemofiltration and osmotic drive in peritoneal dialysis). The intermittent nature of hemodialysis (and hemofiltration) conditions the saw-tooth volume fluctuations that drove to conceiving and implementing the concept of a dry weight, corresponding to normal extracellular volume and blood pressure.

The prevalence of hypertension in hemodialysis (HD) patients has increased over the years. In the early days of maintenance HD blood pressure (BP) control was achieved in most patients. As sessions were shortened, the prevalence of hypertension increased. Yet, in principle, dialysis is able to control hypertension. Today, in programs using long HD, most patients are normotensive without antihypertensive medication. The same is true for patients on daily dialysis, but not for those on short thrice-weekly HD. In all studies reporting BP normalization, dry weight is regularly achieved. Why the poor control of hypertension now? At first sight the shortened session duration is the culprit. This is suggested by several epidemiologic observations and strongly supported by a prospective experience of changing the HD schedule (short to long HD or conversely) in the same group of patients. Recent studies, however, using strict volume control show that BP normalization can be obtained in conventional 3 x 4 hr/week dialysis with relatively low delivered Kt/V(urea). Therefore, prolonging the dialysis time and/or increasing the dialysis dose are not required to achieve BP control. Intensive dialysis most probably normalizes BP by getting the extracellular volume and the amount of sodium in the body back to normal. It acts in conjunction with a moderate dietary sodium restriction and the use of reasonably low dialysate sodium. With this approach improved BP control can be achieved in the vast majority of HD patients.

A long hemodialysis (HD), 3 x 8 hours/week, has been used without significant modification in Tassin for 35 years with excellent morbidity and mortality results. It can be performed during the day or overnight. The relatively good survival is mainly due to a lower cardiovascular mortality than usually reported in dialysis patients. This in turn is mainly due to the good control of blood pressure (BP) including drug-free hypertension control and low incidence of intradialytic hypotension. This control of BP is probably the result of the tight extracellular volume normalization (dry weight), although one cannot exclude the effect of other factors such as serum phosphorus control well achieved using long dialysis. The high dose of small and even more of middle molecules is another essential virtue of long dialysis, leading to good nutrition, correction of anemia, control of serum phosphate and potassium with low doses of medications and providing a very cost-effective treatment. In 2002 one must aim at optimal rather than just adequate dialysis. Optimal dialysis needs to correct as perfectly as possible each and every abnormality due to renal failure. It can be achieved using longer (or more frequent) sessions. Overnight dialysis is the most logical way of implementing long HD with the lowest possible hindrance on patient's life. Due to the change in case mix a decreasing number of patients are able or willing to go on overnight dialysis, education to be autonomous is more difficult, but the benefit is still there.

Aims: Hemodialysis tunneled catheters are widely used nowadays. However, their complications, infection and dysfunction, remain much too frequent. Different types of tunneled silicone hemodialysis catheters are available. We prospectively compared the long-term outcome of the two most popular devices, Permcath cuffed double catheter and TwinCath uncuffed twin catheter, both inserted percutaneously., Methods: From January 1994 to April 1998, 125 tunneled catheters were inserted in the internal jugular vein of 86 chronic hemodialysis patients, 63 TwinCath MedComp (TC) and 62 Permcath Quinton (PC). They were prospectively followed looking for technical patency, infection and dysfunction rate., Results: TC were used more often for iterative access (52 vs. 25%, p = 0.01) and were inserted more frequently in the left internal jugular vein (59 vs. 16% p < 0.001). Their median technical survival rate was longer (869 vs. 433 days for PC, p < 0.01) with a 1-year patency rate of 80 vs. 53% (p = 0.002). Total catheter extrusion was also slightly less frequent with TC (4.7 vs. 9.6%), but partial extrusion happened more frequently (43 vs. 16%, p = 0.02). No significant difference in infection rate was observed, 0.77 for TC vs. 1.3 local infection/1,000 catheter days; 1.08 vs. 1.30 bacteremia/1,000 catheter days. A persistent catheter thrombosis was observed in 7.9 vs. 20.9% in PC (p = 0.04), the number of dysfunction was 10.5 vs. 24/1,000 days in use (p = 0.0001) and the number of urokinase infusion was 4.4 vs. 12/1,000 days (p = 0.001). PC needed more radiological interventions for dysfunction with endolumenal brushes (4 vs. 0) or fibrin sleeve removal (4 vs. 0). The vena cava thrombosis incidence was not different (2 vs. 3)., Conclusion: Although the study was not randomized, TC appears more efficient allowing for a longer patency with a lower dysfunction rate than PC. This was reinforced by less favorable conditions of TC including more left jugular side and more iterative catheters. The cuff does not offer a better bacteriological barrier or protection against extrusion, and the TC seems at a less risk of fibrin sleeves. However, a large randomized study is needed to definitively conclude., (Copyright 2001 S. Karger AG, Basel)

The incidence and prevalence of diabetes mellitus (DM) in the dialysis population in Europe, and more especially in France, have been lagging behind the impressive United States and Japanese rates. For a decade, things have been changing, and the incidence of DM in hemodialysis (HD) reached almost 40 in Tassin, France in 1999. The prevalence has followed the same trend but increased more slowly. The increase in incidence and prevalence is almost totally accounted for by type 2 DM explosive outbreak and development. The morbidity on dialysis (hypotensive episodes, hospitalization number, and duration) was significantly worse in diabetic patients (without difference between type 1 and 2) than in nondiabetic patients. The mortality rate was higher in diabetic patients than in nondiabetic patients (mean half-life 3 and 13 years, respectively), even after adjustment for age and comorbidity. The mortality rate was higher in type 2 than in type 1 (mean half-life 2.7 and 5.2 years, respectively), a difference which disappears when adjusting for age and comorbidity. Specific causes of death were different in diabetic and nondiabetic HD patients; in diabetics there was a six-fold higher cardiovascular (CV) and three-fold higher infectious mortality, but there was the same mortality from cancer. A strong difference was observed between type 1 and type 2 DM: in type 1 there was no increased infectious mortality and a moderately increased CV mortality compared with nondiabetic patients. Type 2 diabetic patients had a four-fold increased infectious and an eight-fold increased CV mortality. Altogether, the eruption of DM in our unit over the last decade has drastically increased the crude mortality, but the standardized mortality ratio using the USRDS mortality table remained unchanged, about 45 of expected mortality.

Central venous stenosis (ST) and thrombosis (TB) related to catheter (KT) had been reported mostly for the subclavian vein. We performed a systematic cavographic study to evaluate the prevalence of these complications in 51 hemodialysis patients with present or previous history of tunneled internal jugular catheter. Each of them had used one or several KT (1.8 +/- 1.4 KT) for a mean 28 +/- 26 month cumulative time (i.e. 43,584 days total exposure time). Fifty percent of the KT were PermCath Quinton and 50% were Twincath (uncuffed) or CS 100 (cuffed) Medcomp. Twenty-seven had no ST (53%, group I), 24 had one or several significant ST (47%, group II) of superior Vena Cava (SVC, n = 4), inferior Vena Cava (IVC, n = 1), Brachio-cephalic Vein (BCV, n = 5) and subclavian vein (SC, n = 10), or a TB of SVC (n = 1), IVC (n = 3), BCV (n = 3), SC (n = 2). This accounts for an incidence of 0.55 ST or TB/1000 patient-days. Five of the twelve subclavian ST and TB had no history of previous subclavian catheter. Comparison between the two groups showed no differences according to age, time on dialysis, diabetes, hematocrit, CRP, cumulative time with catheter, catheter-related infections, type of catheter and anticoagulant treatment. IVC catheter tip's position is an important risk factor for TB and ST (4/6). Twelve group II patients had ST or TB-related symptoms, with a functional AV fistula in 9 cases. Eleven patients underwent repeated percutaneous angioplasty with 4 additional Wallstents and in 2 cases an AV fistula need to be closed. Central venous ST and TB after a jugular KT is extremely frequent, mostly without any symptoms. Consequences on peripheral or central vascular access, cost and poor long-term patency rate of angioplasty are of major importance. These results incite us to further reduce the catheter use in dialysis patients.

While nephrologists wait for the ideal, non invasive, inexpensive, precise, and reproducible tool to evaluate extracellular volume (ECV), they need to exert their clinical acumen in the quest of that holy grail, dry weight (DW). Estimation of DW using a clinical approach based on blood pressure (BP) and ECV is feasible and reliable as shown by successful experiences in various dialysis modes over more than three decades. But a need still exists to resolve difficulties associated with accurate assessment of BP (methods and circumstances of measurement, and the confounding effects of antihypertensive drugs) and ECV (evaluation of weight changes unrelated to ECV, lack of specificity and sensitivity of clinical symptoms, lag time, confusion in terminology). An essential point in clinical assessment of DW is that a normal BP is at the same time the target and the crucial index of DW achievement. For this reason, a trialand-error "probe" process has to be used at intervals to make sure that the dry weight target point is correctly estimated. The various "non clinical" methods proposed for dry weight assessment increase the complexity and the cost of hemodialysis. They are, in the present state of things, more clinical research than practice tools. They do not replace clinical judgment.

Cardiovascular disease is the main cause of the high mortality of dialysis patients and is largely due to poor control of blood pressure. Establishing and maintaining normal extracellular volume (ECV) is required to achieve normotension. The dry weight concept links ECV and blood pressure by a simple clinical relationship. Dry weight is the ideal postdialysis weight that allows a constantly normal blood pressure to be maintained without using antihypertensive medications. Maintenance of normal ECV requires control of salt intake to reduce interdialytic weight gain ( i.e., saline overload) combined with the diffusive and convective removal of salt and water from the body during dialysis sessions. Several problems are to be faced when using the dry weight method. Clinical evaluation must take into account the following confounding factors: weight varies with nutrition, clinical symptoms are unspecific and sometimes discordant, and there is a lag time between ECV and blood pressure changes. On the other hand, achievement of dry weight is hampered by dialysis times that are too short (and weight gains that are too high), by antihypertensive medications, and by poor heart conditions. A longer session time allows for a slower, easier, and more comfortable ultrafiltration.

Agentle ultrafiltration can be achieved using a long and slow hemodialysis. It is easier to achieve gentle ultrafiltration if the interdialytic weight intake is moderate ( i.e., if the patient maintains a low sodium diet) and if diffusion allows for a negative or nil sodium balance during the session ( i.e., dialysate sodium < 140 mmol/L). A gentle ultrafiltration allows control of blood pressure by reducing the extracellular volume to its ideal level, the "dry weight," at the end of the session. Controlling blood pressure reduces cardiovascular mortality, which is by far the foremost cause of death in hemodialysis. Controlling blood pressure means reducing the occurrence of both hypertension and hypotension. Hypotension has been reported to correlate with mortality in hemodialysis as much as or more than hypertension itself. This "U-curve" phenomenon is not paradoxical. It displays two distinct facts on the same figure: an increased early mortality in hypotensive patients (hypotension is a marker of frailty or congestive heart failure, both of which cause increased mortality) and, on the other hand, the well-established, long-term increased mortality in hypertensive patients. Hypotension is not a mandate to undertreat hypertension.

Long, slow hemodialysis (3 × 8 hours/week) has been used without significant modification in Tassin, France, for 30 years with excellent morbidity and mortality rates. A long dialysis session easily provides high Kt/V urea and allows for good control of nutrition and correction of anemia with a limited need for erythropoietin (EPO). Control of serum phosphate and potassium is usually achieved with low-dose medication. The good survival achieved by long hemodialysis sessions is essentially due to lower cardiovascular morbidity and mortality than in short dialysis sessions. This, in turn, is mainly explained by good blood pressure (BP) control without the need for antihypertensive medication. Normotension in this setting is due to the gentle but powerful ultrafiltration provided by the long sessions, associated with a low salt diet and moderate interdialytic weight gains. These allow for adequate control of extracellular volume (dry weight) in most patients without important intradialytic morbidity. Therefore, increasing the length of the dialysis session seems to be the best way of achieving satisfactory long-term clinical results.

Femoral or subclavian central venous catheters are commonly used for temporary vascular access in haemodialysis. We used 36 tunnelized siliconed double lumen catheter (Quinton Permcath or Hickman Bard), most of them in right internal jugular percutaneously. Indication for this catheter were acute or chronic renal failure, plasma exchange, rescue of arterio venous fistula or peritoneal dialysis. Insertion incidents were minors (local haematoma), mean functional time was 51 days. Catheters were changed in 5 cases of infection, 3 cases of obstruction and in 2 accidental remove. Insertion facility, low morbidity, potentially long time use, high blood flow rate with low recirculation argue for this expensive material.

Silicone catheter (C) can be used in the hemodialysis setting as an alternative for the blood access. We analysed retrospectively the 3 types of the catheters used in 45 patients. 58 catheters were percutaneously inserted in the internal jugular vein (9 Bard (B)-Hickman; 17 Canaud (CD)-Vygon; 32 Permcath (PC)-Quinton). The indications were thrombosis or dysfunction of an arterio-venous fistula (A-V F) (52%), absence of a A-V F (21%), Thomas' shunt infection (8%), infection or extrusion of a previous catheter (19%). The functional survival curve of the C shows the best results for the PC and the worse with the B (Log-Rank test = 6,602, p < 0.037). The main cause of failure was the catheter's extrusion (3 of the 5 failures for the B; 4 of the 6 for the CD). None of the PC was extruded. Infection and inadequate blood flow were equally found in the 3 groups. In our experience, PC give the best results because of the quality of the cuff making a good attachment in the sub-cutaneous tunnel.