Peritoneal Equilibration Test Results Research Articles

#4797 ASSOCIATION BETWEEN BLOOD PRESSURE AND SALT CONSUMPTION WITH FLUID STATUS USING BIOIMPEDANCE SPECTROSCOPY IN PERITONEAL DIALYSIS PATIENTS

Abstract Background and Aims Control of extracellular volume in peritoneal dialysis (PD) patients requires both removal of sodium and water. Hypervolemia occurs more frequently in PD patients and is associated with greater morbidity and mortality. Dietary salt restriction (Na+ < 2g) is recommended in all PD patients. Most patients do not comply with this recommendation (prevalence difficult to assess). Bioimpedance spectroscopy (BIS) devices can help assess volume overload in patients receiving maintenance PD. The aim of our study was to determine the association between fluid status as measured using BIS to BP and salt consumption in continuous ambulatory peritoneal dialysis (CAPD) patients. Method We performed a retrospective, longitudinal study, that included 60 PD patients followed at our unit. Demographic and clinical characteristics, such as age, gender, chronic kidney disease (CKD) etiology, time on PD program, dialytic efficacy (Kt/V), peritoneal equilibration test results, BIS results and episodes of peritonitis were registered from our unit database. We measured total sodium removal and estimated daily sodium intake using dietary recall for one day, during the assessment of dialysis adequacy. Based on a 2017 study of 87 patients on PD that sought a correlation between effective daily sodium intake (memory recollection) and urinary + peritoneal sodium sieving. It allowed, through logistic regression, the creation of equations for patients with and without renal residual function (RRF) (Pearson's 0.6). Statistical analyses were performed using SPSS statistics version 23.0. The statistical hypothesis tests with p-value <0.05 were considered significant. Results Sixty patients (male: 60%) with a mean age of 55,9 ± 9 years were selected. Mean time on dialysis was 24,8 months ± 11,9 (min. 2, max. 63). The most common etiology of CKD was glomerular diseases (n = 16, 26.7%), followed by uncertain etiology (n = 11, 18.3%) and diabetic kidney disease (n = 9, 15%). In total, 71,7% of patients were on continuous ambulatory peritoneal dialysis (CAPD). Mean Kt/V was 2,2 ± 0,6 and the majority of patients were high-average transporters. Previous comorbidities were arterial hypertension (n = 60, 100%), diabetes (n = 16, 26,7%), heart failure (n = 13, 21,7%), body mass index >30 kg/m2 (n = 22, 36,7%) and dyslipidemia (n = 40, 66,7%). According to European Society of Cardiology we define three stages of hypertension: stage 1 (140–159/90–99 mmHg) with 15 patients (25%), stage 2 (160–179/100–109 mmHg) with 14 patients (23,3%) and stage 3 (≥180/≥110 mmHg) with 4 patients (6,7%). In total, we have 27 patients (45%) with hypertension under control. A statistically significant positive correlation was found between a status of overhydration (≥2liters) with salt consumption (Na+ >2g) (p = 0,01) and also of hypertension stages 2 and 3 (p = 0,03). Conclusion In PD patients, BIS is a reliable method for evaluating volume status. We found that stable CAPD patients with uncontrolled BP had higher overhydration and salt consumption compared to patients whose BP was controlled. Control of hypervolemia and blood pressure is associated with better cardiac condition. Thus, it is important to encourage patients on peritoneal dialysis to significantly restrict salt intake.

#4793 DOES PRIOR ABDOMINAL SURGERY INFLUENCE TECHNIQUE SURVIVAL OF PERITONEAL DIALYSIS PATIENTS?

Abstract Background and Aims Prior abdominal surgery may result in peritoneal membrane adhesions and fibrosis, compromising the success of peritoneal dialysis (PD). The impact of this factor on peritoneal membrane function and PD technique survival has not been adequately investigated. The aim of our study was to disclosure the effect of prior abdominal surgical procedures on PD technique survival (main outcome), efficacy rates and also evaluate the risk of infectious complications (secondaries outcomes). Method We performed a retrospective, longitudinal study, that included 155 PD patients followed at our unit, since September 2018 to September 2022. Two groups were created: G1 (without previous abdominal surgery) and G2 (with previous abdominal surgery). Demographic and clinical characteristics, such as age, gender, chronic kidney disease (CKD) etiology, time on PD program, dialytic efficacy (Kt/V), peritoneal equilibration test results and episodes of peritonitis were registered from our unit database. Statistical analyses were performed using SPSS statistics version 23,0. The statistical hypothesis tests with p-value <0,05 were considered significant. Results One-hundred and fifty-five patients (female: 50,9%) with a mean age of 55,4 ± 7 years were selected. The main CKD cause was glomerular diseases (n = 43, 27,7%), followed by uncertain etiology (n = 32, 20,6%) and autosomal dominant polycystic kidney disease (n = 21, 13,5%). G1 (n = 87; 56,1%) and G2 (n = 68; 43,9%) had similar distributions of gender (female: 50,6% vs 47,1%, p = 0,061), age (50,4± 9 vs 55,4 ±10 years, p = 0,076) and dialysis vintage (27,9 vs 28,2 months, p = 0,081). In G1, 62,1% of patients were on continuous ambulatory peritoneal dialysis (vs 55,9% in G2). The majority of patients were high-average transporters in both groups (58,6% vs 54,4%, p = 0,066). Previous comorbidities were (G1 vs G2): arterial hypertension (95,4% vs. 98,5%, p = 0,87), diabetes (27,6% vs. 26,5%, p = 0,83), heart failure (25,3% vs. 26,5%, p = 0,64), peripheral arterial disease (28,7% vs 35,3%, p = 0,082), body mass index >30 kg/m2 (20,7% vs 29,4%, p = 0,072) and dyslipidemia (64,4% vs. 64,7%, p = 0,91). In G1, Kt/V was inferior a 1,7 in 36,8% of patients (vs 66,2% in G2, p<0,001). Seven patients (8,1%) have reported more than one peritonitis during time in PD in group 1 (vs 32,4% in G2, p<0,001). We found no differences in PD technique survival between both groups. Transition to hemodialysis happened in 26,4% of patients in G1 (vs 26,5% in G2, p = 0,092). Mortality rate was similar in both groups (6,9% vs 10,3%, p = 0,063). Conclusion According to our results, prior abdominal surgical procedures do not appear to compromise technique survival in patients on PD. Although, abdominal surgical events places PD patients in a higher risk of infectious complications and lower efficacy rates. Thus, this group of patients deserve a more detailed evaluation before starting PD, in order to understand if they are good candidates for the technique, as this may not be the most advantageous for them in the long term.

MO710GALECTIN-3, IS IT A NEW PLAYER IN PERITONEAL INFLAMMATION AMONG PATIENTS UNDERGOING PERITONEAL DIALYSIS?

Abstract Background and Aims Peritoneal dialysis (PD) is a common used method for renal replacement therapy. Prolonged PD treatment causes structural and functional changes in the peritoneal membrane which are attributed to local inflammatory process in the peritoneal cavity. Galectin-3 (Gal-3) is a galactoside-binding lectin with pro-inflammatory and pro-fibrotic effects. The aim of this study was to assess correlation between Gal-3 serum and dialysate effluent levels with peritoneal membrane transport characteristics. Method Gal-3 levels in serum and dialysate effluent were measured simultaneously in prevalent PD patients in morning visit or during peritoneal equilibration test (PET). Gal-3 levels were correlated with clinical and laboratory parameters. Interlukin (IL) -6 levels were measured in dialysate effluent. Gal-3 mRNA and protein expression were evaluated after exposure of primary endothelial cell culture to several dialysate solutions. Results 37 PD patients were included in the study; mean age was 65.7±13.1 years, mean dialysis vintage was 17.5±13 months. Gal-3 levels in dialysate effluent correlated with peritoneal equilibration test (PET) results (0.663, p=0.005) and effluent IL-6 levels (0.674, p=0.002) but not with serum Gal-3 levels or dialysis vintage. Patients with high PET results had higher effluent Gal-3 levels as compared average low PET results. In multivariate regression analysis effluent IL-6 level was the most dominant predictor of effluent Gal-3 levels. Gal-3 mRNA and protein expression in primary endothelial cell culture were not affected by stimulation with dialysate solutions. Conclusion Our study demonstrated presence of Gal-3 within the dialysate effluent in PD patients. Gal-3 levels correlated with peritoneal membrane transport characteristics and effluent IL-6 levels suggesting a role in the inflammatory process within the peritoneal cavity.

Proteomic profiling of peritoneal dialysis effluent-derived extracellular vesicles: a longitudinal study.

Peritoneal dialysis (PD) is an optimal renal replacement therapy for patients while waiting for kidney transplantation, but functional failure of the peritoneal membrane (PM), mainly induced by exposure to PD solutions, force many patients to early abandon PD therapy. PM function is evaluated by the peritoneal equilibration test (PET), a tedious technique only detecting alterations in extensively damaged PM. In a previous study, we showed that peritoneal dialysis effluent contained extracellular vesicles (PDE-EV), and that their proteome was significantly different between newly enrolled and long-term PD patients. Here, we report the results of a longitudinal study and compare PDE-EV proteome changes with PET results. PDE was collected from 11 patients every 6months (coincident with PET controls) from 0months up to 24months on PD. PDE-EV were isolated by size-exclusion chromatography and the proteome was analyzed by mass spectrometry (LC-MS/MS). Bioinformatic analyses were conducted to evaluate differences between groups. At follow-up endpoint, patients were classified as Stable (n = 7) or Unstable (n = 4) according to PET evolution. Strikingly, PDE-EV from the Stable group showed a significantly higher protein expression compared to Unstable patients already at 6months on PD, when PET alterations had not been detected yet. PDE-EV proteome show alterations much earlier than PET monitoring, thus unveiling the potential of PDE-EV proteins as feasible biomarkers of PM alteration in PD patients.

Effect of Initial Peritoneal Equilibration Test Results on Mortality in Peritoneal Dialysis Patients

Effect of Initial Peritoneal Equilibration Test Results on Mortality in Peritoneal Dialysis Patients

Peritonitis before Peritoneal Dialysis Training: Analysis of Causative Organisms, Clinical Outcomes, Risk Factors, and Long-Term Consequences.

Peritonitis before peritoneal dialysis (PD) training (pretraining peritonitis [PTP]) is an uncommon event. The study aim was to examine the causative organisms, clinical outcomes, risk factors, and long-term consequences of PTP. In this single-center, retrospective, observational study involving all incident patients on PD who developed PTP between 1998 and 2012, we examined the causative organisms, primary response rate, complete cure rate, risk factors, and associations of PTP with peritoneal equilibration test (PET) and patient survival. For each patient in the PTP group, the patients who underwent catheter insertion immediately before and after the index case were identified as controls. Among 1252 incident patients on PD, 52 (4.2%) patients developed PTP, and 104 patients were identified as controls. The two groups were similar in age, sex distribution, comorbidities, and residual renal function, but the PTP group had significantly lower hemoglobin and serum albumin. Patients were followed up for a median of 37.5 months (interquartile range [IQR], 16.3-62.2 months). The most common causative organisms of PTP were Staphylococcus aureus (30.8%) and polymicrobial (21.2%); 25% had negative growth. The primary response and complete cure rates were 82.7% and 78.8%, respectively. In the PTP group, 7.7% of patients died, 9.6% of patients required catheter removal, and PD training was significantly delayed (median =42.0; IQR, 26.0-65.8 days versus 27.5; IQR, 23.0-35.0 days; P=0.01). Multivariate logistic regression analysis showed that serum albumin was the only predictor of PTP (adjusted odds ratio, 0.89 per 1-g/dl increase; 95% confidence interval, 0.82 to 0.97). There were no differences in PET results and dialysis adequacy (measured around 1 month after PD training). The PTP group had significantly worse patient survival (median =41.2; IQR, 21.8-60.5 months versus 55.8; IQR, 40.4-71.2 months; P=0.02). Technique failure occurred in 11.5% and 10.6% of patients in the PTP and control groups, respectively. S. aureus is the most common causative organism of PTP. Nutritional interventions in patients who are hypoalbuminemic before catheter insertion deserve additional study.

Effluent Tenascin-C Levels Reflect Peritoneal Deterioration in Peritoneal Dialysis: MAJOR IN PD Study

Peritoneal deterioration causing structural changes and functional decline is a major complication of peritoneal dialysis (PD). The aim of this study was to explore effluent biomarkers reflecting peritoneal deterioration. In an animal study, rats were intraperitoneally administered with PD fluids adding 20 mM methylglyoxal (MGO) or 20 mM formaldehyde (FA) every day for 21 days. In the MGO-treated rats, tenascin-C (TN-C) levels in the peritoneal effluents were remarkably high and a cluster of TN-C-positive mesothelial cells with epithelial-to-mesenchymal transition- (EMT-) like change excessively proliferated at the peritoneal surface, but not in the FA-treated rats. Effluent matrix metalloproteinase-2 (MMP-2) levels increased in both the MGO- and FA-treated rats. In a clinical study at 18 centers between 2006 and 2013, effluent TN-C and MMP-2 levels were quantified in 182 PD patients with end-stage renal disease. Peritoneal function was estimated using the peritoneal equilibration test (PET). From the PET results, the D/P Cr ratio was correlated with effluent levels of TN-C (ρ = 0.57, p < 0.001) and MMP-2 (ρ = 0.73, p < 0.001). We suggest that TN-C in the effluents may be a diagnostic marker for peritoneal deterioration with EMT-like change in mesothelial cells in PD.

The Association Between Peritoneal Charge Barrier Dysfunction and Protein Lost During Continuous Ambulatory Peritoneal Dialysis

Background/Aims: The main purpose of the present study was to determine the effect of peritoneal charge barrier dysfunction on hypoalbuminemia during CAPD. Methods: We measured the association of dialysis dose, peritoneal equilibration test (PET) results (ratio of dialysate and plasma creatinine), and peritoneal charge barrier index (ratio of pancreatic and salivary α-amylase clearance) on protein loss in 33 patients on maintenance CAPD. All patients were from a single institution and were diagnosed with chronic nephritis (n = 18 cases), diabetic nephropathy (n = 8), hypertension (n = 5), and hepatitis B virus-associated glomerulonephritis (n = 2). Results: The mean (± SD) dialysate protein loss was 4.04 g (± 1.97) per day. Protein loss was positively correlated with dialysis dose (r = 0.438, p = 0.01) but was not significantly correlated with PET results. The mean (± SD) peritoneal charge barrier index was 6.12 (± 21.20) and was inversely correlated with protein loss into the peritoneal dialysate (r = -0.532, p < 0.01). Conclusions: Taken together, our study of CAPD patients indicates that protein loss into the peritoneal dialysate increases with peritoneal dialysis dose and with disruption of the peritoneal charge barrier.

The Plasma Permeability Factor in Nephrotic Syndrome: Indirect Evidence in Pediatric Peritoneal Dialysis

Nephrotic syndrome (NS) in children has been associated with a systemic circulating permeability factor. Therefore, once peritoneal dialysis (PD) has been started, peritoneal protein losses should be higher in the nephrotic than in the non-nephrotic population. We compared peritoneal protein losses in children with and without NS on PD. Our retrospective 4-year study analyzed Hispanic patients with NS under PD. Data at dialysis entry and 6 months later were compared. Nutritional support was given according to recommended dietary allowances and recommendations from the Kidney Disease Outcomes Quality Initiative. Clinical and biochemical data were obtained, and 24-hour dialysate and urine samples were collected to measure protein losses. Dialysis dose (Kt/V), daily protein intake (DPI), normalized protein equivalent of nitrogen appearance (nPNA), peritoneal equilibration test (PET), and peritonitis rate were determined. All measurements took place at least 4 weeks after resolution of a peritonitis episode. All patients received automated PD using a HomeChoice PD System cycler (Baxter Healthcare Corporation, Deerfield, IL, USA), with an exchange volume of 1100 mL/m(2) and a dextrose concentration of 1.5% - 2.5%. A control group of non-NS children on PD matched by age and sex were also studied. Data are reported as mean ± standard deviation. Differences between groups were calculated using the Mann-Whitney U-test, and p < 0.05 was considered significant. Each study group consisted of 10 patients [NS patients: 4 boys, mean age of 7.3 ± 4.1 years; control patients: 6 boys, mean age of 7.2 ± 4.7 years (p = nonsignificant)]. In the group with NS, 8 patients were diagnosed by biopsy as having focal segmental glomerulosclerosis, and 2 as having minimal-change disease. At study entry, patients with NS had hourly urinary protein losses of 398 ± 313 mg/m(2) and daily peritoneal protein losses of 3.4 ± 1.9 g/m(2), compared with 29.9 ± 31 mg/m(2) and 1.5 ± 1.1 g/m(2) respectively in the control group (p < 0.05). The same statistical difference was found 6 months later. We observed no statistical differences in PET results, daily exchange volume, and mean dextrose concentration of dialysate. Similarly, no significant between-group differences were observed for Kt/V, DPI, nPNA, and biochemical parameters. Hispanic children with NS on PD show higher peritoneal protein losses than do their control counterparts. Such differences could be secondary to increased peritoneal permeability caused by a systemic permeability factor.

Contribution of Residual Renal Function on Peritoneal Solute Transport in Dialysis Patients

Background: Increased peritoneal solute transport rate (PSTR) is primarily a consequence of continuous exposure to bioincompatible glucose-based peritoneal dialysis (PD) solutions. However, relationships between increasing PSTR and dialysate glucose load remain unclear. As some PD patients with preserved residual renal function do not show increased PSTR despite long-term PD, we examined whether loss of residual renal function is associated with increased PSTR on long-term PD. Methods: We evaluated 35 patients who started PD between 1997 and 2002 and received continuous PD treatment for >6 years. Data included baseline clinical data, residual renal function, urea and creatinine clearance, dialysate glucose load, ultrafiltration, and the use of icodextrin and renin-angiotensin system inhibitors. Peritoneal equilibration test results and data were collected annually for 6 years. Results: Both the glomerular filtration rate and urine volume at 6 years on PD showed significant negative correlations with the dialysate-to-plasma creatinine ratio (D/P Cr) at 6 years (r = –0.716 and r = –0.717, respectively). Multivariate analysis showed only urine volume at 6 years on PD as an independent covariate of the D/P Cr at 6 years on PD. Conclusions: Loss of residual renal function is directly associated with increased PSTR in patients on long-term PD.

Comparisons of the Peritoneal Equilibration Test and Ultrafiltration in Patients with and without Diabetes Mellitus on Continuous Ambulatory Peritoneal Dialysis

Background/Aims: To compare dialysance and ultrafiltration (UF) of peritoneum in diabetes mellitus (DM) and non-DM patients on continuous ambulatory peritoneal dialysis. Methods: A total of 162 adult patients on continuous ambulatory peritoneal dialysis (40 DM and 122 non-DM patients) were studied with the peritoneal equilibration test (PET) using 2.5% glucose dialysis solution retained for 4 h. Patients using 2,000 or 1,500 ml of infusion volume were classified into groups A (23 DM and 63 non-DM patients) and B (16 DM and 41 non-DM patients), respectively. PET results were compared between DM and non-DM patients by unpaired t test. Using Pearson’s correlation and least-square multiple regression, the most powerful predictors of UF rate were also evaluated in DM and non-DM patients. Results: There were no differences between PET parameters and UF rate between DM and non-DM patients in the whole group (WG) and group A. The only significant difference (p < 0.05) was an increased D4/D0 value in DM patients in group B. The most simple but powerful method to predict UF rate was (100 – GAP)/(D4/D0), where GAP corresponds to the glucose absorption percentage and D4/D0 is the PET 4-hour dialysate glucose level/PET 0-hour dialysate glucose level. GAP and D4/D0 were two major determinants of UF rate in the DM group, non-DM group and WG. Conclusions: Peritoneal permeability did not differ between DM and non-DM patients, and GAP and D4/D0 were two major factors predicting UF rate.

Epoetin Responsiveness in Peritoneal Dialysis Patients: A Multi‐center Slovenian Study

The objective of our study was to assess the influence of residual renal function and other factors on epoetin requirements in chronic peritoneal dialysis patients. Fifty-one stable patients (mean age +/- SD: 52 +/- 13 years; 20 women) without recent bleeding, bone marrow disease or malignancy were recruited in four Slovenian centers. The target hemoglobin was above 110 g/L. The peritoneal equilibration test results and relevant clinical and laboratory parameters were recorded. The epoetin resistance index was expressed as a weekly epoetin dose/body weight/hemoglobin concentration. Twenty-four percent of the patients did not need epoetin treatment, the rest were treated with epoetin-beta in a dose of 70 +/- 56 U/kg per week s.c.; the hemoglobin concentration was 124 +/- 15 g/L. Ferritin >100 microg/L and transferrin saturation >20% fulfilled 63% of patients whose epoetin resistance index was not significantly lower (0.43 +/- 0.5 U/kg per week per g/L vs 0.6 +/- 0.72 U/kg per week per g/L, P = 0.502). No difference was found between diabetic and non-diabetic patients. Treatment with angiotensin system antagonists, but not with aluminum phosphate binders, was associated with increased epoetin resistance index (0.56 +/- 0.59 vs 0.3 +/- 0.4 U/kg per week per g/L, P = 0.038). No correlation between epoetin resistance index and residual glomerular filtration rate was found (r = -0.2, P = 0.173). A multiple linear regression analysis showed C-reactive protein, intact parathormone level, female sex and treatment with angiotensin system antagonists to be the independent predictors influencing epoetin resistance index. Our results show that systemic inflammation, secondary hyperparathyroidism and angiotensin system antagonist treatment are the most important modifiable parameters affecting epoetin requirements in stable peritoneal dialysis patients.

Longitudinal changes of solute transport in peritonitis-free peritoneal dialysis patients.

The aim of this study was to evaluate the longitudinal changes in peritoneal transport in patients on long-term, peritonitis-free, continuous ambulatory peritoneal dialysis (CAPD) therapy. Results were longitudinally recorded for the standard peritoneal equilibration test (PET) in 76 consecutive, nondiabetic, adult patients from the beginning of CAPD therapy until their first episodes of peritonitis, abdominal surgery, or any cause of drop out. The PET results were evaluated once annually using the dialysate-to-plasma ratio of creati-nine (D/PCr) and the dialysate-to-instilled dextrose ratio (D4/D0) at 4 hours after beginning dialysis. A total of 168 PET results were obtained. A statistically significant tendency toward decreased D/PCr and increased D4/D0 values over time for up to 3 years was found. This study shows a tendency toward progressive decline in small molecular transport over time in nondiabetic patients with uneventful CAPD therapy. Sequential PET follow-up cannot be overlooked in peritonitis-free CAPD patients.

Association of ENOS polymorphism with basal peritoneal membrane function in uremic patients

Background:Basal peritoneal permeability has a major impact on the outcome of peritoneal dialysis (PD) patients, but the determinant of this is unknown. Early evidence suggests that peritoneal permeability is affected by nitric oxide (NO) activity. Recently, a gene polymorphism of the endothelial NO synthase (ENOS) gene was identified that is associated with circulating nitrate levels. Methods:We performed a cross-sectional study to examine the relationship between ENOS4(a/b) gene polymorphism and basal peritoneal function in 86 Chinese incident PD patients. ENOS genotypes for variable number tandem repeats in intron 4 (a/b) were identified by polymerase chain reaction. Patients were classified into 2 groups according to results of a basal peritoneal equilibration test (PET) performed within 2 months of dialysis therapy: group A consisted of patients with low (L)/L average (LA) PET results, and group B consisted of those with H and HA PET results. Results:Group A (L/LA) had a significantly greater prevalence of ENOS aa/ab genotype than group B (H/HA; 30% versus 12%; P < 0.05). Frequencies of the ENOS a allele also were greater in group A (L/LA) than group B (H/HA) (16% versus 6%; P = 0.03). ENOS genotype remained an independent predictor for peritoneal transport after adjustment for sex, body weight, and prevalence of diabetes by multivariate analysis (adjusted odds ratio, 3.3; confidence interval, 1.1 to 3.7; P = 0.03). Subjects with the aa/ab genotype had significantly lower mass transfer area coefficients (7.35 ± 3.4 versus 9.48 ± 5.21 mL/min; P = 0.023) and dialysate-plasma creatinine ratios at 4 hours (0.55 ± 0.13 versus 0.62 ± 0.14; P = 0.048) than those with the bb genotype. Conclusion:ENOS4(a/b) gene polymorphism is associated with basal peritoneal permeability in uremic Chinese patients.

Feasibility of Reinstitution of CAPD after Partial Hepatectomy in Patients with Malignant Hepatic Tumors

To determine the feasibility of reinstitution of continuous ambulatory peritoneal dialysis (CAPD) in patients with malignant hepatic tumors after partial hepatectomy. Retrospective analysis of 2 CAPD patients. Dialysis unit of a university teaching hospital. Two CAPD patients with malignant hepatic tumors who had undergone partial hepatectomy. Serum biochemistry, Kt/V, peritoneal equilibration test (PET) results before and after hepatectomy. One patient was able to resume CAPD 4 weeks after partial hepatectomy. The other patient was successfully resumed on CAPD after resting the peritoneum for 3 months following partial hepatectomy. The serum biochemistry, Kt/V, and PET results of the 2 patients did not change significantly before and after partial hepatectomy. Reinstitution of CAPD after partial hepatectomy in patients with malignant hepatic tumors is feasible.

The Association of Peritoneal Transport Properties with 24-Hour Blood Pressure Levels in Capd Patients

We aimed to investigate the effects of peritoneal transport characteristics on blood pressure (BP) parameters, measured by 24-hour ambulatory blood pressure monitoring (ABPM), and on the development of left ventricular hypertrophy (LVH) in continuous ambulatory peritoneal dialysis (CAPD) patients. Cross-sectional and prospective design. Tertiary-care center. 25 CAPD patients (11 male, 14 female; mean age 47 +/- 14 years) were included. Mean time on CAPD was 22.9 +/- 18 months and all patients had been dialyzed for more than 6 months. The patients were divided into high, high-average, low-average, and low transport groups according to peritoneal equilibration test results. Daytime and nighttime systolic and diastolic BP and left ventricular mass index among the different peritoneal transport groups; changes in BP parameters before and after increase in ultrafiltration. On 24-hour ABPM records, 13 patients (52%) were found to be hypertensive. Both mean systolic and diastolic BP were significantly increased in high-transporter groups compared to low transporters in both daytime and nighttime BP parameters. Left ventricular mass index was higher in high transporters compared to low transporters, without reaching statistical significance: 160 +/- 23 vs 119 +/- 41 g/m2, p > 0.05. Following increase in ultrafiltration, mean systolic (145 +/- 13 vs 128 +/- 5 mmHg, p < 0.001) and diastolic (96 +/- 10 vs 81 +/- 3 mmHg, p < 0.001) BP decreased, and BP levels returned to normotensive levels in 6 (46%) of the 13 hypertensive patients, requiring discontinuation of antihypertensive drugs. Improvement in volume status resulted in a decrease in both daytime and nighttime BP. Differences in peritoneal transport properties were associated with the development of hypertension and LVH.

The Relationship between Ultrafiltrate Volume with Icodextrin and Peritoneal Transport Pattern according to the Peritoneal Equilibration Test

To establish a relationship between peritoneal transport membrane pattern, analyzed by the peritoneal equilibration test (PET), and drained volume using icodextrin (7.5% Ico) and glucose (3.86% Glu) solutions. Thirty peritoneal dialysis patients were submitted to a standard 4-hour PET and divided into 4 transport categories based on dialysate-to-plasma ratio of creatinine (D/Pcr) and dialysate ratio of glucose at 4 and zero hours of the dwell (D4/D0). Patients were asked to perform exchanges for 2 consecutive nights in 10-hour dwells (2 L 3.86% Glu solution on the first night, and 2 L 7.5% Ico solution on the second night). The drained volume was measured and dialysate samples from the overnight exchanges were obtained for beta2-microglobulin (B2M) levels. PET classification using D/Pcr showed that 46.6% of the patients were high and high-average transporters, or 23.3% when D4/D0 was used. In spite of this difference, both methods showed significant correlation (p = 0.0001, r = 0.862). The mean drained volumes were similar for both solutions (for 3.86% Glu, 2696 +/- 369 mL; for 7.5% Ico, 2654 +/- 424 mL). The high and high-average transport patients classified by D4/D0 achieved a higher ultrafiltration with 7.5% Ico than with 3.86% Glu (p = 0.0235). When classified by D/Pcr, the difference was not significant (p = 0.2243). In the low and low-average transport patients classified by D/Pcr, we observed a significantly lower ultrafiltration when 7.5% Ico was used compared to 3.86% Glu solution (p = 0.0197). Using D4/D0, we saw a tendency toward lower ultrafiltration (p = 0.0719) in the same group. We then correlated the PET results and the difference between drained volume with 7.5% Ico and 3.86% Glu solution [deltaV (I-G)]. We found a significant negative correlation between D4/D0 and deltaV (I-G) (p = 0.002, r = -0.5390), and a positive correlation between D/Pcr and deltaV (I-G) (p = 0.005, r = 0.4932). The levels of B2M obtained with 7.5% Ico were higher than those obtained with 3.86% Glu solution (for 7.5% Ico, 9.47 +/- 6.71 microg/vol; for 3.86% Glu, 7.29 +/- 4.91 microg/vol; p = 0.004). Furthermore, we found significant correlation between the total amount of B2M obtained with 7.5% Ico solution and D4/D0 (p < 0.0001, r = -0.4493), and D/Pcr (p < 0.0001, r = 0.5431). Mean drained volume was similar between the two solution groups. High transporters, as defined by D4/D0, achieved higher ultrafiltration with 7.5% Ico than with 3.86% Glu solution. This is most likely due to the higher number of small pores in the peritoneal membrane. Low transporters, as classified by D/Pcr, achieved lower ultrafiltration with 7.5% Ico than with 3.86% Glu solution. The deltaV (I-G) and the PET results showed significant correlation, confirming that high transporters have a higher ultrafiltration volume with 7.5% Ico. The total B2M mass obtained with 7.5% Ico was greater than with 3.86% Glu solution and significantly higher in the high transport patients, indicating a larger number of small pores. Thus, the deltaV (I-G) could give us an idea of the peritoneal transport pattern in peritoneal dialysis patients.

A preceding exchange with polyglucose versus glucose solution modifies peritoneal equilibration test results

The peritoneal equilibration test (PET) is an important tool for evaluating peritoneal membrane characteristics. The polyglucose icodextrin induces ultrafiltration caused by colloid osmosis through the small pores of the peritoneal membrane and therefore is especially effective during long dwell times. The main indications for polyglucose solutions are daytime dwells in patients on automated peritoneal dialysis and nighttime exchanges in continuous ambulatory peritoneal dialysis (CAPD) patients. In CAPD patients, PET is started immediately after the icodextrin exchange. Therefore, we performed two PETs in each of 15 CAPD patients. PET post-1.36% glucose was performed immediately after a preceding exchange with 2 L of 1.36% glucose dialysate solution (dwell time, 10 hours). PET postpolyglucose was started immediately after a preceding exchange with 2 L of 7.5% icodextrin solution (dwell time, 10 hours). The dialysate to plasma (D/P) ratio of creatinine, phosphate, and sodium during PET postpolyglucose was significantly greater than during PET post-1.36% glucose at 1, 2, 3, and 4 hours of dwell time. The quotient of dialysate glucose at 1, 2, and 4 hours of dwell time to dialysate glucose at 0 dwell time was significantly lower in PET postpolyglucose compared with PET post-1.36% glucose. In the case of creatinine, phosphate, and glucose, PET postpolyglucose curves tended to be steeper than those of PET post-1.36% glucose during the first hour of dwell time, whereas both curves were parallel between 1 and 4 hours of dwell time. The course of D/P ratio curves of urea nitrogen, protein, and albumin was nearly identical between PET postpolyglucose and PET post-1.36% glucose. In a subgroup of 5 patients, D/P ratios of creatinine and phosphate were also greater in PET postpolyglucose compared with PET performed after a long dwell with 2.27% glucose solution. Before a scheduled PET, CAPD patients using icodextrin solution during the nighttime should perform their nighttime exchange with conventional glucose solution. © 2001 by the National Kidney Foundation, Inc.

Natural changes in peritoneal equilibration test results in continuous ambulatory peritoneal dialysis patients: a retrospective, seven year cohort survey.

We conducted a retrospective, 7 year cohort survey to examine the natural changes in peritoneal equilibration test (PET) results in patients with long-term uneventful continuous ambulatory peritoneal dialysis (CAPD). Thirty-two (17 males, 15 females) patients on CAPD with two or more standard PETs performed more than 6 months apart, in the absence of peritoneal insult, were included. Changes and pattern of PET results were evaluated by the dialysate to plasma ratio of creatinine (D:P-cre), the fourth h dialysate to instilled glucose ratio (D4:Do) and ultrafiltration volume (UF, ml). The subgroups included high (H), high-average (HA), low-average (LA), or low (L) transporters with the dividing ratios (D:P-cre) of >0.81, >0. 65 to 0.81, >0.5 to 0.65, and <0.5, respectively. The median D:P-cre significantly decreased (p = 0.04), but neither the D4:Do nor the final median UF significantly decreased. The change in D:P-cre was strongly and inversely correlated with the initial D:P-cre value (r = -0.68; p < 0.05). A similar relationship was found between the change in the final D4:Do and the initial D4:Do (r = -0.752; p < 0. 01) and between the change in the final UF and the initial UF (r = -0.875; p < 0.01). No correlation was found between the change in D:P-cre and the age of the patient, the time interval between PETs, monthly dialysate glucose exposure, or underlying diabetes/non-diabetes. The final peritoneal transport pattern was altered with 5 (15.6%) patients remaining in the extreme subgroups (H or L) and, by contrast, 84.4% (27/32) of the patients now in the averaged (HA or LA) groups (p < 0.01, chi2 test). We demonstrated a natural "centralization" migration of PET results after long-term uneventful CAPD, which may help to explain why patients with extreme PET characteristics, that is, H or L, continued to do well on CAPD.

Transperitoneal transport in diabetic and non-diabetic patients on peritoneal dialysis.

To investigate differences in the transport characteristics of the peritoneal membrane between diabetic and non-diabetic patients on chronic peritoneal dialysis, a study was conducted in 21 non-diabetic and 18 diabetic patients. Transperitoneal transport of small solutes was evaluated in terms of the mass transfer area coefficients (urea, creatinine and glucose), ultra-filtration sieving coefficients (urea and creatinine) and by peritoneal equilibration test results. The capacity of the peritoneal membrane to transport macromolecules was evaluated by albumin mass transfer rates and clearances of albumin. Transperitoneal water transport was evaluated by the ultra-filtration properties and the lymphatic flow rates. Finally, the whole-body capillary permeability was estimated by measuring the unidirectional flux of albumin across the capillary wall, i.e. the transcapillary escape rate of 125I-labelled human albumin. Despite a significantly increased transcapillary escape rate of albumin in the diabetic patients, no differences in peritoneal membrane characteristics could be demonstrated between diabetic and non-diabetic patients on peritoneal dialysis.