Abstracts Nephrology Dialysis Transplantation MP513 IMPACT OF RESIDUAL RENAL FUNCTION ON CLINICAL OUTCOME AND QUALITY OF LIFE IN PATIENTS ON PERITONEAL DIALYSIS Kallel Hend2, Krid Madiha2, Jbeli Hela2, Khedher Rania2, Ben Mami Ikram2, Smaoui Wided2, Ben Fatma Lilia2, Ben Hmida Fethi1, Raies Lamia2, Beji Soumaya2, Zouaghi Mohammed Karim2 1 Laboratory of renal disease LR00SP01 Charles Nicolles Hospital Tunis Tunisia and 2 Nephrology Rabta Hospital Tunis Tunisia INTRODUCTION AND AIMS: The preservation of residual renal function (RRF) has become of paramount importance to nephrologists in the clinical management of patients on peritoneal dialyse PD. We studied the impact of RRF on clinical outcome and quality of life in 90 patients on peritoneal dialysis (PD). METHODS: All consecutive patients receiving PD between January 2007 and December 2016 were included. The study was carried out at Rabta Hospital, Tunis, Tunisia. A total number of 90 patients were enrolled after obtaining their consents. They were assigned to two groups, at the time of initiation of PD, based on their estimated RRF: RRF was estimated by calculating glomerular ﬁltration rate (GFR) expressed as a mean of creatinine and urea clearance (ml/min/1, 73 m): high RRF group (with eGFR 5 mL/min/1.73 m2) and low RRF (with eGFR <5 mL/min/1.73 m2). Seventy tow patients were in the high RRF group and 18 patients in the low RRF. A record of the following clinical and biochemical parameters was made: weight, BMI, blood pressure BP, urine output, eGFR , ultra ﬁltration, serum albumin, hemoglobin, serum potassium , serum alkaline phosphatase (ALP), serum phosphorous. Parathyroid hormone (PTH) and vitamin D, levels were measured. During the study, number of peritonitis events were recorded. Sleep quality assessment was carried out using the Pittsburgh Sleep Quality. Depression was assessed during the similar time frame, using the Becks Depression Score BDS . We excluded from the study patients who died within three months of initiation of PD . RESULTS: Baselines characteristics including age, sex, BMI, and native kidney disease were similar in both groups. The number of patients who discontinued CAPD were thirty (41, 66%) in the high RRF group and 6 (33.33%) in low RRF group.Six (8.33%) patients in high RRF group had at least one episode of peritonitis whereas 8 (44.44%) of patients in the low RRF group had peritonitis. As assessed by PSQI, in high the RRF group, 36 patients (50%) had normal sleep quality score, eighteen (25%) had mild sleep disturbances and eight (25%) had moderate sleep disturbances, and none had severe sleep disturbances. In low RRF group, 9 patients (50%) had normal score, tow (11, 11%) had mild sleep disturbances, and 6 (33.33%) had moderate sleep disturbances, and one (5.55%) had severe sleep disturbances. Thirty six patients (50%) in the high RRF group had normal depression score, 26 (33.3%) had mild depression and 10 (13.88%) had moderate depression, and none had severe depression. In low RRF group, four patients (22.22%) had normal score, ten (55.55%) had mild depression, three (16.66%) had moderate depression and one (5.55%) had severe depression. We observed a better correlation between RRF and serum albumin concentration and a tendency toward better nutritional status in patients with RRF .Serum ALP level was low in high RRF group (Table 1) CONCLUSIONS: We found that a high RRF at the time of initiation of PD, signiﬁcantly decreased the incidence of infections, depression, better nutrition, and lower levels of alkaline phosphatase. We need to develop treatment plans that focus on preserving RRF in dialysis patients MP514 IMPACT OF SOLUTE EXCHANGE BETWEEN ERYTHROCYTES AND PLASMA ON HEMODIALYZER CLEARANCE Jacek Waniewski2, Jan Poleszczuk1 Department of Mathematical Modelling of Physiological Processes Nalecz Institute of Biocybernetics and Biomedical Engineering Warszawa Poland and 2Department of Mathematical Modelling of Physiological Systems Nalecz Institute of Biocybernetics and Biomedical Engineering Warszawa Poland 1 INTRODUCTION AND AIMS: During the ﬂow of blood through hemodialyzer small solutes are removed from plasma to dialysis ﬂuid across the dialyzer membrane and from erythrocytes to plasma across the cellular membrane. The rate of exchange of solutes between cells and plasma inﬂuences the performance of hemodialyzer. A mathematical model was applied to assess the impact of this exchange on the effective hemodialyzer clearance. METHODS: The model describes the ﬂow of solutes in the countercurrent dialyzer with one phase ﬂow of dialysis ﬂuid in the dialysate channel and two phase ﬂow of plasma water and water in cellular blood components (erythrocytes) in the blood channel. The one dimensional approach to the distribution of solute concentration in the channel cross-section is assumed. The channels are characterized by their volumes and the solute transport characteristics by diffusive permeability of the dialyzer membrane KoA, the transmittance coefﬁcients of the dialyzer, and the diffusive permeability of cellular membrane, PAer. The rate of ultraﬁltration is assumed to be constant. Computer simulation of the model predicts the proﬁle of the solute distribution along the dialyzer channels, the change of the proﬁles with time, and three clearances: 1) dialyzer clearance KD calculated using the amount of solute removed with dialysate over its concentration in inlet plasma, 2) plasma clearance KP calculated using the amount of solute removed from plasma over its concentration in inlet plasma, 3) erythrocyte clearance KE calculated using the amount of solute removed from erythrocytes to plasma over the difference in its concentration in inlet cellular water. The typical values of the volumetric ﬂow rates in dialyzer and dialyzer membrane diffusive permeability for urea and creatinine were assumed. The cellular membrane permeability for urea and creatinine were taken as estimated by Schneditz et al, 2009. RESULTS: For the constant solute concentrations in plasma water and cellular water at the inlet to dialyzer the steady state of the transport in dialyzer is obtained after around two minutes for both solutes. The results were however much different for urea and creatinine. The urea concentrations proﬁles in plasma water and cellular water are similar along the dialyzer and the system behaves as the removal was from the whole water in the blood channel. In contrast, the creatinine concentration in cellular water changes only slightly along the dialyzer and the system may be approximated as the removal of creatinine from plasma water. For a standard dialysis (blood and dialysis ﬂuid inﬂow of 300 and 500 mL/min, respectively, zero ultraﬁltration, hematocrit 35%), permeability of dialyzer membrane KoA = 789 and 556 mL/min, and permeability of cellular membrane PAer = 78400 and 4.4 mL/min for urea and creatinine, respectively, the clearances for urea were KD = 219.5, KP = 162.0, KE = 64.3 mL/min and KD = 169.9, KP = 165.0, KE = 2.2 mL/min for creatinine. CONCLUSIONS: The highly different diffusive permeability of cellular membrane for urea and creatinine yields much different contribution of blood cellular compartment to the removal of these solutes from blood in dialyzer: whereas urea is removed from the whole blood water without any hindrance in cellular membrane, creatinine is removed practically from plasma water only. Typically, the dialyzer clearance, KD, is close to the sum of plasma clearance, KP, and cellular clearance, KE. MP515 FLUID STATUS ASSESSMENT USING BIOELECTRICAL IMPEDANCE ANALYSIS IN ELDERLY HEMODIALYSIS PATIENTS Alvita Gincaite1, Vaidas Vicka1, Diana Sukackiene2, Migle Gudynaite1, Agne Laucyte-Cibulskiene2, Laurynas Rimsevicius2,1, Marius Miglinas2,1 1 Faculty of Medicine Vilnius University Vilnius Lithuania and 2Center of Nephrology Vilnius University Hospital Santariskiu Klinikos Vilnius Lithuania MP513 Figure INTRODUCTION AND AIMS: The amount of elderly patients undergoing hemodialysis (HD) is steadily increasing. Therefore age related problems are gaining more relevance in hemodialysis patients care, one of them is chronic ﬂuid overload. Our aim was to compare ﬂuid status between young and elderly patients using bioelectrical impedance analysis (BIA) and to evaluate possible risk factors associated with ﬂuid overload in these patients. METHODS: We conducted an observational study in a tertiary reference hospital. Fluid state of 99 HD patients was examined post HD procedure using BIA data, such as intracellular (ICW) and extracellular water, extracellular water (ECW)/total body water doi:10.1093/ndt/gfx175 | iii617 Downloaded from https://academic.oup.com/ndt/article-abstract/32/suppl_3/iii617/3854295 by guest on 25 July 2019 volume overload accompanied by retention of nitrogenous waste products and some electrolytes. The aim of the present study was to evaluate the efﬁcacy of Cross Linked Polyelectrolyte (CLP) on adsorption of ﬂuid, nitrogenous waste products and electrolytes. METHODS: In an experimental study on 30 hemodialysis patients, the effect of CLP on adsorption of ﬂuid, urea, creatinine, uric acid, sodium and potassium of dialysate efﬂuent were evaluated. 500 ml of efﬂuent ﬂuid of each patient were collected at the begining of dialysis. The concentrations of urea, creatinine, uric acid, sodium and potassium of ﬂuid were measured by standard methods. Then efﬂuent samples were treated with 6g CLP and incubated for 4h at 37 . The efﬁcacy of CLP on adsorption of water, and waste products was evaluated. Statistical analysis was performed using SPSS software and result was presented as mean +/- SD and p-value was set at 0.05. RESULTS: Up to 80% of efﬂuent ﬂuid water was adsorbed by CLP. There was signiﬁcant reduction of urea, creatinine, uric acid and sodium in the remaining efﬂuent ﬂuid (p<0.001). In contrast, the amount of potassium has been increased in the efﬂuent ﬂuid. CONCLUSIONS: this study showed that CLP can adsorb signiﬁcant amount of ﬂuid and nitrogenous waste products and in the future it may be used to reduction of dialysis dose especially in volume overload patients.