Modelling of icodextrin hydrolysis and kinetics during peritoneal dialysis.

In peritoneal dialysis, ultrafiltration is achieved by adding an osmotic agent into the dialysis fluid. During an exchange with icodextrin-based solution, polysaccharide chains are degraded by α-amylase activity in dialysate, influencing its osmotic properties. We modelled water and solute removal taking into account degradation by α-amylase and absorption of icodextrin from the peritoneal cavity. Data from 16 h dwells with icodextrin-based solution in 11 patients (3 icodextrin-exposed, 8 icodextrin-naïve at the start of the study) on dialysate volume, dialysate concentrations of glucose, urea, creatinine and α-amylase, and dialysate and blood concentrations of seven molecular weight fractions of icodextrin were analysed. The three-pore model was extended to describe hydrolysis of icodextrin by α-amylase. The extended model accurately predicted kinetics of ultrafiltration, small solutes and icodextrin fractions in dialysate, indicating differences in degradation kinetics between icodextrin-naïve and icodextrin-exposed patients. In addition, the model provided information on the patterns of icodextrin degradation caused by α-amylase. Modelling of icodextrin kinetics using an extended three-pore model that takes into account absorption of icodextrin and changes in α-amylase activity in the dialysate provided accurate description of peritoneal transport and information on patterns of icodextrin hydrolysis during long icodextrin dwells.

Extracorporeal versus peritoneal ultrafiltration in diuretic-resistant congestive heart failure--a review.

Diuretic-resistant congestive heart failure in the form of type 2 cardiorenal syndrome is a problem of growing significance in everyday clinical practice because of high morbidity and mortality. There has been scant progress in the treatment of overhydration, the main cause of symptoms in this group of patients. The aim of our review is to present recent advances in the ultrafiltration therapy of congestive heart failure, with special attention to the new dedicated device for extracorporeal isolated ultrafiltration, as well as modifications of peritoneal dialysis in the form of peritoneal ultrafiltration with icodextrin solution and incremental peritoneal dialysis. Technical and clinical features, costs and potential risks of available devices for isolated ultrafiltration are presented. This method should be reserved for patients with true diuretic resistance as part of a more complex strategy aiming at the adequate control of fluid retention. Peritoneal ultrafiltration is presented as a viable alternative to extracorporeal ultrafiltration because of medical and psychosocial benefits of home-based therapy, lower costs and more effective daily ultrafiltration. In conclusion, large, properly randomized and controlled clinical trials with long-term follow-up will be essential in assessing the logistics and cost-effectiveness of both methods. Most importantly, however, they should be able to evaluate the impact of both methods on preservation of renal function and delaying the progression of heart failure by interrupting the vicious circle of cardiorenal syndrome. Our review is supplemented with the case report of the use of peritoneal ultrafiltration with a single 12-hour nighttime icodextrin exchange as a life-saving procedure in a patient with congestive heart failure resistant to pharmacological treatment.

Long Peritoneal Dialysis Dwells With Icodextrin: Kinetics of Transperitoneal Fluid and Polyglucose Transport.

Background and objective: During peritoneal dialysis (PD), the period of effective net peritoneal ultrafiltration during long dwells can be extended by using the colloidal osmotic agent icodextrin but there are few detailed studies on ultrafiltration with icodextrin solution exceeding 12 h. We analyzed kinetics of peritoneal ultrafiltration in relation to icodextrin and its metabolites for 16-h dwells with icodextrin. Design, setting, participants, and measurements: In 20 clinically stable patients (mean age 54 years; 8 women; mean preceding time on PD 26 months), intraperitoneal dialysate volume (VD) was estimated from dilution of 125I-human serum albumin during 16-h dwell studies with icodextrin 7.5% solution. Sodium was measured in dialysate and plasma. In 11 patients, fractional absorption of icodextrin from dialysate, dialysate, and plasma amylase and high and low (Mw <2 kDa) Mw icodextrin fractions were analyzed. Results: Average VD increased linearly with no difference between transport types. At 16 h, the cumulative net ultrafiltration was 729 ± 337 ml (range -18 to 1,360 ml) and negative in only one patient. Average transcapillary ultrafiltration rate was 1.40 ± 0.36 ml/min, and peritoneal fluid absorption rate was 0.68 ± 0.38 ml/min. During 16 h, 41% of the initial mass of icodextrin was absorbed. Plasma sodium decreased from 138.7 ± 2.4 to 136.5 ± 3.0 mmol/L (p < 0.05). Dialysate glucose G2-G7 oligomers increased due to increase of G2-G4 metabolites while G6-G7 metabolites and higher Mw icodextrin fractions decreased. In plasma maltose and maltotriose (G2-G3 metabolites) increased while higher Mw icodextrin oligomers were almost undetectable. Dialysate amylase increased while plasma amylase decreased. Conclusions: Icodextrin resulted in linear increase of VD with sustained net UF lasting 16 h and with no significant difference between peritoneal transport types. In plasma, sodium and amylase declined, G2-G3 increased whereas larger icodextrin fractions were not detectable. In dialysate, icodextrin mass declined due to decrease of high Mw icodextrin fractions while low Mw metabolites, especially G2-G3, increased. The ability of icodextrin to provide sustained UF during very long dwells - which is usually not possible with glucose-based solutions - is especially important in anuric patients and in patients with fast peritoneal transport.

[Glucose polymer in the long dwell exchanges in peritoneal dialysis--advantages and limitations]. / Zastosowanie polimeru glukozy, w dlugich otrzewnowych wymianach dializacyjnych--korzysci i ograniczenia.

The alternative dialysis solution containing glucose polymer- icodextrin was developed in response to disadvantages of conventional glucose solution such as metabolic disorders, structural changes in the mesothelium and glucose absorption from peritoneum leading to dissipation of the osmotic gradient and decrease of ultrafiltration. Icodextrin is especially indicated in patients with impaired ultrafiltration. In the paper current review of literature referred to the ultrafiltration effect of icodextrin in the long dwell exchanges was presented.

[Biocompatibility of dialysis fluid in peritoneal dialysis--limitations and possibilities of improvement]. / Biozgodnosc plynu dializacyjnego w dializie otrzewnowej--ograniczenia i mozliwosci poprawy.

Standard glucose dialysis solutions are characterised by low biocompatibility because of hyperosmolality, low pH, lactate buffer and presence of glucose degradation products. These factors cause failure of peritoneum as dialysis membrane. In our paper we present problems of biocompatibility of glucose-based solutions as well as possibilities of improvement in this field thanks to application of alternative solutions.

[Schönlein-Henoch purpura--case report]. / Plamica Schönleina-Henocha--opis przypadku.

Schönlein-Henoch purpura is a systemic vasculitis characterised by purpura, joints and gastrointestinal involvement and glomerulonephritis. Organs injuries are associated with the deposition of immune complexes containing IgA in the wall of small vessels. This disease rarely affects adults. On the basis of the case of 50 years old man clinical presentation, prognosis and treatment are presented.

Peritoneal transport in peritoneal dialysis patients using glucose-based and amino acid-based solutions.

OBJECTIVE: To evaluate peritoneal transport of fluid and solutes in continuous ambulatory peritoneal dialysis (CAPD) patients using amino acid (AA)-based versus glucose-based dialysis solutions. METHODS: Using iodine-labeled human serum albumin ((125)I-HSA) as intraperitoneal volume marker, peritoneal transport was investigated in a group of 20 clinically stable patients (11 females and 9 men, age 53 +/- 15 years) on CAPD for 15 - 101 months. Two paired 4-hour dwells, one with 1.36% glucose and one with 1.1% AA dialysis solution, were performed in each patient. Intraperitoneal dialysate volume, fluid absorption rate, and diffusive mass transport coefficients (K(BD)) and sieving coefficients (S) for glucose, creatinine, urea, potassium, and total protein were estimated for each dwell study. Dwell studies with AA solution were used to estimate K(BD) values for individual AAs. RESULTS: Intraperitoneal dialysate volume was higher for AA solution in comparison with glucose solution due to the higher osmolality of the AA solution. No statistically significant difference was found for K(BD) or S for creatinine, urea, potassium, or total protein in the dwell studies with either solution, whereas K(BD) for glucose was higher with AA than with glucose solution. Mean values of K(BD) of AA were similar but with high standard deviation, reflecting inter-individual variations in peritoneal transport rate. CONCLUSION: Our results indicate that the AA peritoneal transport rate is strongly dependent on transport characteristics of the individual peritoneal membrane.

[Causes and clinical implications of hypervolemia in peritoneal dialysis]. / Przyczyny i implikacje kliniczne przewodnienia w dializie otrzewnowej.

In our paper we present actual data from world literature as well as own experiences with respect to chronic hypervolemia as a very important clinical problem in peritoneal dialysis. We discussed the causes and clinical picture of hypervolemia as well as differential diagnosis of ultrafiltration failure as a potential cause of hypervolemia in peritoneal dialysis patients. Special attention was paid to the kinetic modelling of sodium and water removal in peritoneal dialysis.

[Enoxaparin in haemodialysis]. / Enoksaparyna w hemodializie.

Using of low-molecular-weight heparins (LMWH) in haemodialysis therapy significantly reduced the incidence of haemorrhagic complications with the same clinical efficacy in comparison to standard unfractionated heparins. Taking enoxaparin as example, we present the mechanisms of action of LMWH paying special attention to efficacy in haemodialysis and adverse effects.

[Bacteremic shock in the course of urinary tract infection--case report]. / Wstrzqs bakteriemiczny w przebiegu zakazenia ukladu moczowego--opis przypadku.

On the basis of 51 years old, so far healthy patient with urinary tract infection we present appearance of bacteremic shock of severe clinical course complicated with multiorgan failure. Increased level of cardiac enzymes in the blood followed by sudden cardiac arrest enabled us to differentiate between cardiogenic and bacteremic shock.

["Abdominal catastrophe" in peritoneal dialysis]. / "Katastrofa brzuszna" w dializie otrzewnowej.

Abdominal catastrophe in peritoneal dialysis is defined as peritonitis secondary to visceral injury with enteric organisms in dialysate. This complication is associated with a high mortality rate. Peritonitis associated with abdominal catastrophe is extremely difficult to diagnose. This review refers to the special aspects of pathogenesis, diagnosis and therapy of peritonitis due to visceral injury.

[Sterile peritonitis associated with the use of icodextrin solution. Case report]. / Jalowe zapalenie otrzewnej podczas stosowania wymian dializacyjnych plynem zawierajacym ikodekstryne. Opis przypadku.

Sterile peritonitis after dialysis with the use of icodextrin-containing solution is a rare complication of peritoneal dialysis programme. On the basis of the case of hypersensitivity to icodextrin accompanied by peritonitis, the diagnostic problems were described and a review of literature on this complication is presented.

[Influence of parathormone level on the doses of human recombinant erythropoietin in haemodialysed patients]. / Wplyw stezenia parathormonu na dawke ludzkiej rekombinowanej erytropoetyny u chorych przewlekle hemodializowanych.

UNLABELLED: The purpose of the study was to determine the doses of rHuEPO, which are necessary to obtain the same correction of renal anaemia in chronically haemodialysed patients with different levels of iPTH. 25 haemodialysed patients with stable values of iPTH for at least 6 months (mean age 58 +/- 15.6 years; 6 females and 19 males on haemodialysis from 1 to 126 months) were divided into 3 groups: group 1 (7 patients) with iPTH < 100 pg/ml, group 2 (12 patients) with iPTH 100-300 pg/ml and group 3 (6 patients) with iPTH > 300 pg/ml. In all groups adequacy of haemodialysis (HD) measured by Kt/V was similar. Every month the following data were determined: Ca, P, CaxP product, HCT, HGB, Fe, transferrin saturation (TSAT) and weekly dose of rHuEPO. Patients with chronic infections, neoplastic diseases or those after blood transfusions were excluded from the study. Significantly higher weekly dose of rHuEPO was needed in patients with iPTH > 300 pg/ml to obtain similar correction of renal anaemia in comparison with patients with iPTH from 100 to 300 pg/ml. There were no statistically significant differences between the groups with respect to other data except significantly higher values of Cas in the group with iPTH > 300 pg/ml. CONCLUSION: Higher doses of rHuEPO to obtain the same correction of renal anaemia are necessary only in patients with iPTH > 300 pg/ml.

[Diverticulosis as a background of "abdominal catastrophe" in the course of peritoneal dialysis. Care Report]. / Uchylkowatosc jelita grubego jako tlo "katastrofy brzusznej" w przebiegu dializoterapii otrzewnowej. Opis przypadku.

Peritonitis complicating peritoneal dialysis (PD) may represent a difficult diagnostic and therapeutic problem if it coexists with surgical pathology of intra-abdominal organs defined as "abdominal catastrophe". The illustration of this problem is the case of 70-year-old patient treated with automated PD, in whom recurrent episodes of peritonitis (Escherichia coli) were typical of "abdominal catastrophe" and were probably caused by microperforations of the colon in the course of diverticulosis.

[Comparison of peritoneal transport of solutes and water during CAPD with glucose or amino acids solutions. Preliminary report]. / Porównanie transportu przezotrzewnowego czasteczek i wody podzas ciaglej ambulatoryjnej dializy otrzewnowej prowadzonej z zastosowaniem plynu glukozowego lub aminokwasowego. Doniesienie wstepne.

The aim of the study was the comparison of peritoneal transport of solutes and water during dialysis with presently used 1.1% amino acid solution in relation to 1.36% glucose solution. 20 clinically stable patients on CAPD for 50.0 +/- 27.6 months were enrolled into the study. On the basis of blood and dialysate samples taken during 4-hour CAPD, intraperitoneal dialysate volume and diffusive mass transport coefficients (KBD) for: glucose, creatinine, urea, sodium, potassium and total protein were calculated. Intraperitoneal dialysate volume was higher in the case of amino acid solution in comparison to glucose solution. The KBD values for the investigated solutes were higher when amino acid solution was used, but for glucose and sodium the KBD values were statistically significantly higher. In conclusion, the differences in transperitoneal transport of solutes and water between both solutions found in our study suggest better clinical usefulness of amino acid solution than standard glucose solution for achieving adequate ultrafiltration.

Peritoneal dialysis as a therapeutic approach in congestive heart failure resistant to pharmacological treatment.

Given an increasing number of patients with congestive heart failure (CHF) refractory to diuretics, new and more effective therapeutic modalities are sought. Peritoneal dialysis (PD), which provides continuous, slow ultrafiltration, may be an alternative to hemodialysis in this population. The current paper, based on a comprehensive literature review, addresses the role of PD in improving the quality of life of patients with CHF.

The kinetics of water transperitoneal transport during long-term peritoneal dialysis performed using icodextrin dialysis fluid.

INTRODUCTION: Dialysis fluid containing icodextrin is used in patients on peritoneal dialysis (PD) because of its significant ultrafiltration properties. The use of the fluid in treating patients with congestive heart failure resistant to diuretics has also been reported. OBJECTIVES: The aim of the study was to evaluate water peritoneal transport during a 16-hour dialysis exchange performed using icodextrin-containing dialysis fluid. PATIENTS AND METHODS: Eleven clinically stable patients were enrolled in the study (5 women and 6 men; mean age, 50.4 +/- 18.3 years), treated with PD for 26.9 +/- 22.4 months. Water transperitoneal transport was evaluated using a modified version of Babb-Randerson-Farrell thermodynamic model of membrane transport with human albumin marked with iodine as the marker of intraperitoneal volume. Based on blood and dialysate samples collected during the 16-hour dialysis exchange, the intraperitoneal volume of dialysate and dialysate reverse absorption were calculated. RESULTS: There were no clinical complications associated with the use of icodextrin fluid during the study. A significant increase in intraperitoneal volume of dialysate (950 ml on average) compared to the initial value was observed in the whole group at the 16th hour of the exchange. CONCLUSIONS: The study demonstrated that dialysis fluid with icodextrin ensured effective ultrafiltration during a 16-hour dialysis exchange. This indicates its potential usefulness in the treatment of patients with severe congestive heart failure with or without coexisting end-stage renal disease.

Peritoneal dialysis as a therapeutic approach in congestive heart failure resistant to pharmacological treatment: case report.

This report describes the use of continuous peritoneal dialysis (PD) as an alternative to hemodialysis (HD) in a patient with type 2 cardiorenal syndrome in the course of congestive heart failure resistant to standard pharmacological treatment. A 39-year-old man presented with a 24-year history of progressive heart failure. Ineligibility for heart transplant and previous inefficient treatment with different modifications of HD reduced his treatment options to PD. After 7 months of continuous PD (1 overnight exchange with icodextrin and 2 daily standard continuous ambulatory PD exchanges) his overall condition significantly improved compared with his status while on HD. An increase from NYHA class IV to class II, increase in left ventricular ejection fraction from 50% to 55%, decrease in right ventricular systolic pressure from 73 to 53 mmHg, and improvement in the quality of life enabled him to resume his daily activities.