Reduction in urea distribution volume over time in clinically stable dialysis patients.

We have previously shown that, assuming urea distribution volume (V) remains constant for 1 month, ionic dialysance (ID) allows the dialysis dose to be calculated without the need for blood sampling. The aim of this multicenter study was to verify whether the assumption of a constant V can be extended to 1 year. In clinically stable patients receiving thrice-weekly hemodialysis at 13 dialysis centers, V and Kt/V were assessed during three dialysis sessions at baseline and 1 year later using ID as dialyzer urea clearance and the single-pool urea kinetic model. Baseline albumin, hemoglobin, and C reactive protein were prespecified covariates for predicting the change in V over time. Of the 52 enrolled patients, 40 (25 males; age 63.0+/-13.5 years) completed the study. Baseline end-dialysis body weight (62.4+/-13.7 kg) showed a non-significant 1% reduction during follow-up (-0.6+/-2.8 kg; P=0.175), whereas V significantly decreased from 29.0+/-6.8 to 27.4+/-6.0 l (-1.6+/-3.0 l or 4.5%; P=0.002). The reduction in V was greater when baseline albumin was lower (P=0.001) and baseline V was higher (P=0.005). The single-pool K(t)/V calculated using baseline V underestimated the actual value by 0.07+/-0.16 (P=0.008). The slight underestimate of Kt/V during follow-up suggests that annual V evaluations may be sufficient for dialysis dose quantification as the only risk is underestimating the actually delivered dialysis dose. However, the relationship between baseline albumin and the reduction in V over time may have nutritional value, and suggests more frequent V evaluations.

[HFR vs HDF-ON line: plasmatic amino acids loss evaluation]. / HFR vs HDF on-line: valutazione della perdita aminoacidica plasmatica.

PURPOSE: The high convection dialytic techniques, such as hemodiafiltration (HDF), can cause the loss of important molecules such as growth factors, vitamins and amino acids. Hemodiafiltration reinfusion (HFR) is an HDF on-line process, using a sipping cartridge, able to remove uremic toxins and give back a "repaired" ultra-filtrate to the patient. We aimed to establish the plasmatic amino acid levels before and after dialysis in HFR vs. HDF on-line, with scrupulous attention to branched chain amino acids (BCAA) such as isoleucine, leucine and valine. These amino acids, often present with low plasmatic levels in hemodialyzed patients, seem to be related to a picture of malnourishment. METHODS: Eleven male patients on bicarbonate dialysis, for at least 1 yr, were evaluated (average dialytic age = 88 months, /average age = 67 yrs), with good dialytic efficiency and body mass levels, randomized in HFR or HDF on-line (filter PAN AN 69) for 1 week of treatment, respectively. The different results of each method were controlled for the same patient. Blood samples were taken before and after dialysis in each 2nd hemodialytic weekly session. Total amino acids, essential, non-essential and BCAA were determined by gas-chromatography. RESULTS: There was no difference detected in pre-dialytic plasmatic levels of analyzed amino acids between the two groups. In post-dialysis, HDF patients demonstrated a total essential, non-essential amino acid and BCAA higher loss rate, compared to HFR patients. Post-dialysis amino acid level averages were: total amino acids in HDF 1852 +/- 302.6 micromol/L, in HFR 2395 +/- 492.8 micromol/L (p = 0.018); essential amino acids in HDF 428.8 +/- 118.2 micromol/L, in HFR 510.3 +/- 129.3 micromol/L (p = 0.022); non-essential amino acids in HDF 1176 +/- 213 micromol/L, in HFR 1546 +/- 339.2 micromol/L (p = 0.01); BCAA in HDF 242.7 +/- 83.42 micromol/L, and in HFR 286.7 +/- 89.9 micromol/L (p = 0.03). CONCLUSIONS: Since low plasmatic BCAA levels are related to anorexia and malnourishment, the loss of these amino acids can be important in the dialytic technique choice. HFR can offer an outstanding advantage, combining a high convection treatment with medium molecule removal, without compromising physiologic molecule loss.

Effect of high-flux dialysis on the anaemia of haemodialysis patients.

BACKGROUND: Anaemia is one of the major clinical characteristics of patients with chronic renal failure, and has a considerable effect on morbidity and mortality. Adequate dialysis is of paramount importance in correcting anaemia by removing small and medium-sized molecules, which may inhibit erythropoiesis. However, high-molecular-weight inhibitors cleared only by means of highly porous membranes have also been found in uraemic serum and it has been claimed from uncontrolled studies that high-flux dialysis could improve anaemia in haemodialysis patients. METHODS: We therefore planned this multicentre randomized controlled trial with the aim of testing whether the use of a large-pore biocompatible membrane for a fixed 12-week follow-up improves anaemia in haemodialysis patients in comparison with the use of a conventional cellulose membrane. Eighty-four (5.3%) of a total of 1576 adult haemodialysed patients attending 13 Dialysis Units fulfilled the entry criteria and were randomly assigned to the experimental treatment (42 patients) or conventional treatment (42 patients). RESULTS: Haemoglobin levels increased non-significantly from 9.5+/-0.8 to 9.8+/-1.3 g/dl (dP=0. 069) in the population as a whole, with no significant difference between the two groups (P:=0.485). Erythropoietin therapy was given to 32/39 patients (82%) in the conventional group, and 26/35 (74%) in the experimental group (P:=0.783) with subcutaneous administration to 26/32 patients in conventional and to 23/26 patients in experimental group, P:=0.495. Dialysis dose (Kt/V) remained constant in both groups (from 1.30+/-0.17 to 1.33+/-0.20 in the conventional group and from 1.28+/-0.26 to 1.26+/-0.21 in the experimental group, P:=0.242). Median pre- and post-dialysis beta(2)-microglobulin levels remained constant in the conventional group (31.9 and 34.1 mg/dl at baseline) and decreased in the experimental group (pre-dialysis values from 31.1 to 24.7 mg/dl, P:=0.004 and post-dialysis values from 24.8 to 20.8 mg/dl, P:=0.002). Median erythropoietin doses were not different at baseline (70 IU/kg/week in conventional treatment and 90 IU/kg/week in experimental treatment, P:=0.628) and remained constant during follow-up (from 70 to 69 IU/kg/week in the conventional group and from 90 to 91 IU/kg/week in the experimental group, P:=0.410). Median erythropoietin plasma levels were in the normal range and remained constant (from 12.1 to 12.9 mU/ml in the conventional group and from 13.2 to 14.0 mU/ml in the experimental group, P:=0.550). CONCLUSIONS: This study showed no difference in haemoglobin level increase between patients treated for 3 months with a high-flux biocompatible membrane in comparison with those treated with a standard membrane. When patients are highly selected, adequately dialysed, and have no iron or vitamin depletion, the effect of a high-flux membrane is much less than might be expected from the results of uncontrolled studies.

[Safety in dialysis rooms. Biologic risks]. / La sicurezza in sala dialisi. Il rischio biologico.

The search for quality in the health service cannot lead aside the safety of its operators and users, subject to the well defined parameters of Law 626. This study makes a preliminary examination of the accidents occurring in our Health District which comprises three hospitals, 600 beds and 1,800 employees. A total of 172 accidents have been reported. The percentages can be broken down between the various sectors: 73% of accidents involve nurses, 9% involve doctors and 1% administrative personnel. The greatest risk in hemodialysis is the biological factor (through accidental cuts or pricks which account for 67% of the accidents reported) and involves humans (both patients and personnel), monitors and environments as the sources of pathogens. The most frequently isolated germs are E. coli and Pseudomonas. It has been shown that prevention is above all based on the accuracy with which procedures are followed. The risk of hepatitis C has not yet been resolved, as is affinned in a review reported in the study. The HIV risk gives the greatest cause for concern, even if only 0.2% after exposure compared to 15-36 for HbsAg. Compliance with universal rules for prevention and post-exposure procedures provides an adequate guarantee for prevention.

[Nephrotic syndrome refractory to conventional therapy]. / Sindrome nefrosica refrattaria alla terapia convenzionale.

BACKGROUND: Prednisone is the choice medicine in Nephrotic Syndrome (NS) treatment, possibly associated with immunosuppressor medicines (cyclophosphamide or chlorambucil), either in case of NS resistance at cortisone therapy or with frequent relapses. Cyclosporin A (CyA) use has been recently proposed, due to its inhibitory effect on the IL2 and lymphokine release, with a permeabilizing effect on the glomerular membrane. The purpose of this study is to evaluate the CyA antiproteinuric effectiveness with NS conventional therapy refractory patients. METHODS: Six patients (3 females and 3 males) have been treated with CyA (4 +/- 0.5 mg/Kg/die) associated with low corticosteroid dosages. RESULTS: During the treatment, proteinuria reduced in 5 patients, at less than 1/3 of pre-treatment values, for 4 patients this happened starting from the 2nd month of therapy, while after the 12th for the fifth patient. The sixth patient has now a 2/3 reduction compared to the initial one and he is at the 3rd month of therapy. During the CyA treatment, further to the proteinuria reduction, a total proteinemia values increase and a cholesterolemia and tryglyceridemia reduction has been observed, while creatinine and PA have not changed. CONCLUSIONS: Four out of the six treated patients have been respectively under therapy for 2,3,12,30 months. Two stopped CyA therapy: one after 18 months due to clinical stability, still present after 2 years from interruption; one after 9 months with a stable clinical picture for just three months, since she was longing for a pregnancy, achieving a quick proteinuria relapse.

[Heart failure resistant to drug therapy. Nephrologic approach]. / Scompenso cardiaco resistente ai farmaci. Approccio nefrologico.

BACKGROUND: The congestive heart failure (IV cl. NYHA) refractory to medical therapy, can be treated with ultrafiltrative method such as extracorporeal ultrafiltration (UF), intermittent veno-venosus hemofiltration, intermittent peritoneal dialysis (IPD) or chronic ambulatory peritoneal dialysis (CAPD). METHODS: Sixty-one patients suffering from SCC have been managed by combining medical therapy with ultrafiltrative treatment. RESULTS: 28% (17 patients) died within a week from ultrafiltrative therapy beginning. 39% (24 patients) took up to respond to medical therapy (responders). 33% (20 patients) didn't give a proper response to pharmacological therapy (non responders), therefore a ultrafiltration program with chronic ambulatory peritoneal dialysis (CAPD) has been undertaken. Among ultrafiltrative methods applied to patients, IVVH is the most effective. Clinical parameters analysis, relevant to dehydration acute phase, points out: an evident loss of corporeal weight between dehydration pre-post phases in all 3 groups, with statistically significant results; a SAP values reduction between the beginning and the end of treatment in all 3 groups; a PAD values reduction in the group of deceased and non responders. This value remains stable in responders group. Non responders patients, inserted in a ultrafiltration program with CAPD present the following survival rate: 55%: 6 months; 35%: 1 years; 15%: 4 years. These patients maintain a good self-management in 50%, sufficient in 35% and totally partner-dependent in 15%. CONCLUSIONS: Ultrafiltration method together with pharmacological therapy allows a resetting of neuro-endocrine and electrolytic system in refractory congestive heart failure patients and a recovery of a pharmacological response. Without such a response a cardio-circulatory balance can be maintained through a CAPD method.

[Peritoneal dialysis and chronic dobutamine, two experiences contrasted. Possible role and indications in refractory cardiac decompensation]. / Dialisi peritoneale e dobutamina cronica, due esperienze a confronto. Possibili ruoli ed indicazioni nello scompenso cardiaco refrattario.

UNLABELLED: The number of patients who develop heart failure (HF) is increasing and is expected to increase further in the next decade. Despite the availability of an ever-widening array of pharmacological therapy, patients with end-stage HF have a poor long-term prognosis. Little attention has been paid to alternative non-conventional therapy for these patients. The aim of this non-randomized study was to describe two non-conventional approaches in patients with HF, refractory to conventional medical therapy. The feasibility and long-term efficacy of a continuous ambulatory peritoneal dialysis (CPAD: 20 patients) or dobutamine intermittent infusions (DOB: 11 patients) was analysed: the mean dobutamin dose was 5 gamma/kg/min, and the interval period treatment ranged from 12 hours/day to 12 hours/week. RESULTS: Both treatments were feasible and non major procedure complications occurred. The 6 and 12 month survival rates were 55% (14/20 patients), 35% (9/20 patients) and 36% (6/11 patients), 18% (3/11 patients) in the CAPD patients and DOB patients, respectively. All patients survived at one year (38% = 12/31 patients) documented a significant functional improvement and quality of life. The conclusions is drawn that the use of CAPD and DOB should be considered in those with refractory HF, in whom medical therapy has failed and in whom home training is considered feasible. Further studies are necessary to define those patients who will benefit from one of these strategies and to confirm these preliminary data.

[Medical nephropathies: what has changed in 20 years]. / Nefropatie mediche: cosa è cambiato in 20 anni.

The authors analyse the series of patients with medical nephropathy undergoing renal biopsy between 1973 and 1993 in order to make a diagnostic and prognostic comparison between the first (ID) and second (IID) decade. Clinical indications for biopsy, which became more precise during the second decade, led to the diagnosis of fewer patients with normal histology; the introduction of ME and IF allowed non-significant histological conditions to be reduced during IID; echo-guided biopsy has led to a reduced number of post-biopsy complications in IID compared to ID. Epidemiological analysis reveals the reduction of focal glomerulosclerosis in IID in favour of glomerulonephritis with IgA deposits in correlation with the use of IF; the increase in mebranous glomerulonephritis secondary to increased antigenic stimuli; reduced acute post-infective glomerulonephritis and membrane-proliferative glomerulonephritis owing to an improved prophylaxis of sources of infection. Among the patients undergoing renal biopsy and commencing dialysis an increase was observed in IID in the number of cases of membranous glomerulonephritis or caused by IgA deposits. There was an increased interval between biopsy and the start of dialysis in IID compared to ID, in spite of fewer patients receiving immunosuppressive therapy. This was probably due to the increased number of pathologies with a slower evolution, thus justifying the postponement of the start of dialysis.

[Cost methodologies in dialysis in relation to the Italian National Health Service]. / Metodologie dei costi in dialisi in rapporto all'azienda salute italiana.

This work analyses the economic aspects of dialysis in Italy in relation to government resources allocated to the health service in general. The authors illustrate the procedures used to estimate the resources required by the dialytic programme. The costs of dialytic programmes in different cities and at different periods in the history of the Italian health service are compared. A concrete example is outlined of the economic management of dialysis and the authors demonstrate how the results were obtained using cost analysis.

[Variability of the response to recombinant human erythropoietin in patients undergoing hemodialysis treatment]. / Variabilità di risposta all'eritropoietina umana ricombinante nei pazienti in trattamento emodialitico.

The paper assesses the existence of possible interference between dialysis and the response to human recombinant erythropoietin administered i.v. in a group of patients undergoing regular dialysis. The results obtained show that the time taken to reach the set hemoglobin target (Hb 10 g%) was shorter in hemodiafiltered (HDF) patients compared to those receiving bicarbonate dialysis (BD). A plausible explantation may be the different depurative characteristics and the greater degree of biocompatibility of alternative dialysis which is able to achieve a more rapid cellular response to pharmacological stimulation.

[High-efficiency membranes and the dialysis solution]. / Membrane ad alta efficienza e bagno di dialisi.

During this work through the total bacterial count and of the pseudomonas and the determination of the positive substances to Limulus Amebocyte Lysate test, bacterial pollution of the liquid bicarbonate concentrate has been determined together with the influence that preparation conditions and the entity of interval between the said preparation and utilization of concentrates have on it. Through the evaluation of the cardiac rate and the systemic arterial pressure, we have studied the influence of the bacterial pollution on the clinical of the patient. Analysing the obtained data we can point out that the liquid bicarbonate concentrate present an elevated degree of contamination which feels the effects of the production and storage procedures. The remark of inverse correlation between systemic arterial pressure and endotoxin level of the dialysate seems to reconfirm the importance of the bacterial contamination on the clinical of the patient.