The new ELISIO-H® dialyzer (henceforth referred to as ELISO-H) is a high-flux dialyzer made from the POLYNEPHRON™ fiber designed and manufactured by Nipro Corporation of Japan. The dialyzer has undergone in vitro testing, and all legally required biological safety tests have been successfully completed and certified by an external institute. A number of clinical studies have been completed for this particular dialyzer, in Japan and in Europe. Nipro ELISIO-H dialyzers have been commercially available for several years outside of United States On December 20, 2013, ELISIO-H dialyzer obtained 510k approval for use in United States. The aim of the study was to confirm the safety and clinical effectiveness of the Nipro ELISIO-H for the US market by comparing its performance characteristics and hemocompatibility with Gambro Polyflux Revaclear® (henceforth referred to as Revaclear) and Fresenius Optiflux® (henceforth referred to as Optiflux) dialyzers, currently in use in the United States. This study was performed under the oversight of the University of Missouri Columbia Institutional Review Board. As this study falls under the category of a clinical study per US requirements (with reference to the European Standard ISO 14155 and the Declaration of Helsinki), informed consent was obtained from all patients enrolled in the study. Ten clinically stable patients who satisfied inclusion criteria and were on maintenance hemodialysis were selected from the Dialysis Clinics Incorporated (DCI) in-center hemodialysis population. All patients were receiving regular maintenance HD via AV fistula for 4 hours per session, three times a week. Specific patient inclusion, exclusion, and withdrawal criteria are provided in Appendix I. All patients in the study were dialyzed on Gambro Phoenix X36 hemodialysis machine (Baxter Healthcare, Deerfield, IL, USA). The dialyzers used were the Elisio 21H, Elisio 17H (Nipro Medical Corporation, Osaka, Japan), Optiflux F200NR, Optiflux F160NR (Fresenius Medical Care, Waltham, MA, USA), and Revaclear Max and Revaclear (Baxter Healthcare) (see Table 1 for dialyzer characteristics). Orders for anticoagulation type, dosage, and administration were not changed unless specified otherwise by the investigator/physician. The total amount of anticoagulant was carefully documented for each patient. The blood flow rate (Qb) was kept in the range of 300–500 mL/min, as prescribed by the patient's nephrologist. The dialysate flow (Qd) rate was set to twice the blood flow rate. Dialyzer setup and preparation was done per dialysis clinic's normal standard operating procedure (details available on request). This involved a pre-rinsing step before the start of dialysis. The priming solution was not infused to the patient. Dialysate flow was initiated at the beginning of the rinsing procedure. All the dialyzers were pre-rinsed in the same manner. The type of heparin and dosage normally used for each individual patient, including the administration regimen (bolus injection and continuous infusion), remained unchanged unless specified otherwise by the investigator or patient's nephrologist during the evaluation. The blood flow rate (Qb) was kept between 300 and 500 mL/min. The dialysate flow rate (Qd) was kept at two times the Qb. Blood flow and dialysates flow were not changed for any patient throughout the study period. The ultrafiltration rate (Uf) was maintained per physician's orders for each patient during each treatment and appropriately documented. Three consecutive treatments were performed for each patient with each dialyzer type in a pre-specified randomly assigned sequence: Elisio, Fresenius, Gambro; Gambro, Elisio, Fresenius; and Fresenius, Gambro, Elisio. Five minutes before the collection, the flow rate was adjusted so that at time of collection, Qb = 350 mL/min, Qd = 700 mL/min, and Uf = 0 for all patients. Blood was collected from venous side first followed by arterial side. Blood was collected pre, during, and post-dialysis at appropriate intervals (see Appendix II). (See Appendix III for the equations used for the above mentioned calculations.) All blood samples were collected after confirming that the blood and dialysate flows were at the targeted rates listed above. Venous and arterial pressures at the point of collection were recorded as well. All the blood analyses were performed by a commercial laboratory (Boyce & Bynum Pathology Laboratories, P.C., Columbia, MO, USA). All data, including blood flow rates, dialysate composition, heparin schedule (i.e., concentration in the pre-rinsing solution, bolus, and infusion rates), all medications given to or taken by the patient, and standard dialysis symptom/events seen routinely in dialysis patients were recorded in the case report form. Patient records included patient names, dates of birth, End Stage Renal Disease (ESRD) diagnosis, and duration of treatment on dialysis. Data were stored in a locked dataset in a secure computer in the Nephrology Research Laboratory. Data were analyzed in house using SigmaPlot for Windows 11.2 (Systat Software, Inc., San Jose, CA, USA) for statistical analysis. Parametric non-paired t-test was used to compare groups except where the data failed the normality test or the variance test, when the nonparametric Mann–Whitney Rank Sum was utilized to test for significance. The study group (Table 2) consisted of eight males and two females with an average age of 57.2 ± 10.9 years. There were six African Americans (A) and four Caucasians (C) with an average time on dialysis of 3.8 ± 3.2 years. The etiology of ESRD was Diabetes Mellitus type 2 in six, Polycystic kidney disease in three, and hypertension in one patient. Six patients had left upper arm fistulae, one patient had left forearm fistula, one patient had right upper arm fistula, and two patients had right femoral fistulae. Mean serum values of different solutes at various time points are given in Table 3 for the three dialyzers. Table 4 shows 60 minute clearances by session (Monday: seesion 1; Wednesday: session 2; and Friday: session 3) and dialyzer type with any significant differences (P < 0.05). There was no significant difference in whole blood small solute clearance or removal rates among different dialyzers. B2 microglobulin and myoglobin clearances were significantly higher in Elisio as well as Revaclear when compared to Optiflux dialyzers. No significant difference was present between Elisio and Revaclear dialyzers (Figure 1a,b). The clearance for myoglobin in Optiflux dialyzer was calculated as a negative value when compared with Elisio and Optiflux dialyzers in sessions 1 and 2 (Table 4). Removal rates of B2 microglobulin and myoglobin were significantly higher in Elisio as well as Revaclear when compared to Optiflux dialyzers (Figure 2a,b). No significant difference was found between Elisio and Revaclear dialyzers. The removal rate for myoglobin in Optiflux dialyzer was calculated as a negative value when compared with Elisio and Optiflux dialyzers in all three sessions. The percentage change in TAT levels at 240 minutes in Elisio, Revaclear, and Optiflux dialyzers was significantly higher (Figure 3) when compared to that of 60 minute values (data not shown). There was no significant difference in the percentage change at 60 or 240 minute TAT levels between any of the dialyzers studied (Table 5). C5a levels did not show any significant percentage change in any of the timed blood samples (15, 30, 60, and 240 minutes) in either Elisio or Revaclear dialyzers. In Optiflux dialyzers, C5a levels at 30, 60, and 240 minutes were significantly lower than 15 minute levels in terms of percentage change. Also, the 240 minute levels showed a significant rise when compared to 60 minute levels (data not shown). When percentage change (from baseline) in C5a levels (Table 5) was compared between various dialyzers, both Elisio and Revaclear showed significant differences at 15 minutes when compared to Optiflux (P < 0.001 and <0.001, respectively). There was also a significant change seen at 240 minutes levels between Optiflux vs. Revaclear (P < 0.005) (Table 5). The WBC count at 30, 60, and 240 minutes in Elisio dialyzers was significantly higher (percentage change) when compared to 15 minute values. No difference in WBC count was observed in Optiflux and Revaclear dialyzers between various timed blood draws (data not shown). There was no significant percentage change between different dialyzers (Table 5). The hemoglobin levels in Elisio dialyzers showed a significant rise (percentage change) at 240 minutes when compared to 15, 30, and 60 minutes. In Optiflux dialyzers, the 240 minute rise in hemoglobin was only significantly different when compared to 15 minute values. In Revaclear dialyzers, the 240 minute levels of hemoglobin were significantly higher when compared to 15 and 60 minute values (data not shown). No difference in percentage change in Hb levels was observed (Table 5). In both Elisio and Revaclear dialyzers, the mean Hematocrit levels at 240 minutes were significantly higher (percentage change) than 15 minute levels. Optiflux dialyzers showed no difference among various timed values (data not shown). No significant difference in percentage change was seen among various dialyzers (Table 5). There was no significant difference between various timed values of platelet counts for any of the three dialyzers studied (data not shown). The percentage change in platelet count at 30 minutes showed a significant decline in Elisio dialyzers when compared to Revaclear (P < 0.009). No other significant differences in percent change in platelet counts were observed between different dialyzers (Table 5). The small solute clearance (urea, creatinine, and phosphate) in Elisio dialyzer was comparable and not significantly different from the two reference dialyzers. In contrast, the clearances and removal rates of low molecular weight (LMW) proteins, that is, B2 microglobulin and myoglobin were significantly higher in Elisio and Revaclear dialyzers when compared to Optiflux dialyzers. There was no difference in the clearance or removal rates of LMW between Elisio and Revaclear dialyzers. The removal and clearance of larger molecules (like LMW proteins) by standard dialysis membranes is limited by their relatively higher molecular weights as well as lower sieving coefficients. The molecular weights of B2 microglobulin and myoglobin are 11 and 16.7 kDa, respectively. The sieving coefficient for B2 microglobulin is 0.7 (Revaclear) and 0.22 for myoglobin (ELISIO 15H) (Table 1). Possible contribution by membrane adsorption may also contribute to low or negative clearance of larger molecules in some membranes (i.e., Optiflux in our study). All dialysis sessions were completed successfully without any significant clotting. The TAT profile in Elisio dialyzer was similar to the other two dialyzers and not significantly different from Optiflux or Revaclear dialyzers in terms of percent change in TAT activity. The stability of C5a levels in Elisio dialyzers as well as a lack of any significant difference in percentage change in C5a activity when compared to the other two dialyzers (except with Optiflux dialyzer at 15 minutes) shows that the inflammatory activation with Elisio is similar to the other reference dialyzers. These data validate the observation that the thrombogenic and inflammatory potential of the Elisio dialyzer is overall similar to the other two reference dialyzers. The WBC count profile of the Elisio dialyzer showed significantly higher 30, 60, and 240 minute values (percentage change) when compared to 15 minute values. The lack of a significant difference in the percentage change in WBC count among different dialyzers confirms that the effect of Elisio dialyzer on WBC counts is similar to the other reference dialyzers. All three dialyzers showed a rise in hemoglobin levels with time during hemodialysis sessions (hemoconcentration effect). Similar trends were observed in hematocrit values in Elisio and Revaclear dialyzers. The lack of a significant difference in percentage change on comparing hemoglobin and hematocrit values among the three dialyzers confirms the observation that the effect of Elisio dialyzer on the hemoglobin and hematocrit is similar to the other two reference dialyzers. Similarly, platelet counts demonstrated a stable profile with Elisio dialyzers. The lack of any significant difference in percentage change in platelet counts among the three dialyzers confirms that the effect of Elisio dialyzers on platelet count is similar to the other two reference dialyzers. Taken overall, this confirms that ELISIO-H has similar hemocompatibility profile when compared to the other two reference dialyzers. This comparative analysis of Elisio-H dialyzer shows no difference in small solute clearance when compared to the Optiflux or Revaclear dialyzers. The large solute clearance by Elisio-H was similar to Revaclear and better than Optiflux dialyzers. No clinically meaningful difference was found among the three dialyzers when hemocompatibility parameters were studied. Overall, this analysis confirms the clinical effectiveness and safety profile of Elisio-H. Therefore, Eliso-H dialyzer is an acceptable alternative to other currently available dialyzers in use in the United States. Patient inclusion criteria Patient exclusion criteria Withdrawal criteria Sampling to be done for every dialysis treatment (three times per dialyzer, per patient). % Removal rate: ((([S]T0 – [S]T240) / [S]T0) * 100) % Change: (((TX1…Xi – T0) / T0) * 100) 60 minute clearance: ((([S]60'Art – [S]60'Ven) / [S]60'Art) * Qb) where [S] = solute concentration; T0 = time point 0; TX1…Xi = time points 1–4; T240 = time point 240 minutes; Qb = blood flow rate.

Peritoneal dialysis (PD) is a life-sustaining therapy for end-stage renal disease (ESRD), used by 10–15% of the dialysis population worldwide. Peritoneal fibrosis (PF) is a known complication of long-term PD and frequently follows episodes of peritonitis, rendering the peritoneal membrane inadequate for dialysis. Transforming growth factor (TGF)-β is an inducer of fibrosis in several tissues and organs, and its overexpression has been correlated with PF. Animal models of peritonitis have shown an increase in expression of TGF-β in the peritoneal tissue. Decorin, a proteoglycan and component of the extracellular matrix, inactivates TGF-β, consequently reducing fibrosis in many tissues. Recently, gold nanoparticles (GNP) have been used for drug delivery in a variety of settings. In the present study, we tested the possibility that GNP-delivered decorin gene therapy ameliorates zymosan-mediated PF. We created a PF model using zymosan-induced peritonitis. Rats were treated with no decorin, GNP-decorin, or adeno-associated virus-decorin (AAV-decorin) and compared with controls. Tissue samples were then stained for Masson's trichrome, enface silver, and hematoxylin and eosin, and immunohistochemistry was carried out with antibodies to TGF-β1, α-smooth muscle actin (α-SMA), and VEGF. Animals which were treated with GNP-decorin and AAV-decorin gene therapy had significant reductions in PF compared with untreated animals. Compared with untreated animals, the treated animals had better preserved peritoneal mesothelial cell size, a significant decrease in peritoneal thickness, and decreased α-SMA. Quantitative PCR measurements showed a significant decrease in the peritoneal tissue levels of α-SMA, TGF-β, and VEGF in treated vs. untreated animals. This study shows that both GNP-delivered and AAV-mediated decorin gene therapies significantly decrease PF in vivo in a rodent model. This approach has important clinical translational potential in providing a therapeutic strategy to prevent PF in PD patients.

This study compares patient and technique survival on continuous ambulatory peritoneal dialysis (CAPD) and other peritoneal dialysis (PD) modalities in relation to body size indicators, race, sex, and peritoneal transport characteristics. Data were abstracted from a PD adequacy database, with 354 patients subjected to analysis. Transfers between PD modalities were almost exclusively from CAPD to various offshoots of PD, mostly due to inadequate dialysis or inadequate ultrafiltration. Survival analysis showed better technique survival for other PD modalities compared to CAPD when body mass index was less than 25 kg/m2, body surface area (BSA) was less than 1.9 m2, total body water was less than 39 L, and the dialysate-to-plasma ratio of creatinine at four hours was less than 0.65 by the peritoneal equilibration test (PET). There were no differences found in relation to gender, race, or PET ratio of dialysate glucose at four hours to dialysate glucose at time zero. In other PD modalities, no differences in technique and patient survival were found in regard to the same parameters, with the exception of better technique survival in males with a BSA over 1.9 m2. In conclusion, CAPD technique survival is better in the small patient with below average peritoneal transport characteristics. In other PD modalities, survival is not related to anthropometric indices or peritoneal transport characteristics.

Technique survival in continuous ambulatory peritoneal dialysis (CAPD) depends mostly on clearances in relation to body size and residual renal function (RRF). Our clinical impression has been that when RRF fails, larger patients leave CAPD sooner than smaller patients do. Peritoneal equilibration tests (PETs) and 24-hour adequacy evaluations performed in 277 patients in a single center from 1986 through 2009 were abstracted from the existing peritoneal dialysis adequacy database. A PET (using 2 L of 2.5% dextrose dialysis solution) was performed in 272 patients during the first 4 months of dialysis. Every 3 months, the patients brought their 24-hour urine and dialysate collections for adequacy evaluations and had height and weight recorded. Body surface area (BSA), body mass index (BMI), and total body water (TBW) were calculated. There were 1372 adequacy evaluations abstracted. The number of patients gradually declined over time because of death (28%) or transfer to other peritoneal regimens (25%) or to hemodialysis (23%). A small number of patients received a kidney graft (6%) or left CAPD for other reasons (12%); only 6% of patients remained on CAPD after 80 months of treatment. The mean (+/- standard deviation) PET 4-hour values were 0.652 +/- 0.128 for dialysate-to-plasma (D/P) ratio of creatinine (Cr), 0.403 +/- 0.0969 for 4-hour dialysate-to-initial dialysate (D/D0) glucose concentration ratio, and 2336 +/- 211 mL for the drain volume. There was no correlation between PET D/P Cr and BSA (r = 0.0051, p = 0.934), PET D/D0 glucose and BSA (r = 0.0042, p = 0.945), or PET drain volume and TBW. The correlations with other size indicators were very poor. None of the large patients (BSA > 1.9 m2, weight > 75 kg, BMI > 25 kg/m2) remained on CAPD for more than 80 months once they lost RRF. These results confirm our impression that, with declining RRF, larger patients do not continue CAPD as long as smaller patients do.

Self-cannulation has been shown to decrease complications and extend the life of the arteriovenous fistula. Teaching self-cannulation has been difficult due to patient distress created by the use of needles. This article discusses a technique that has been used in the authors' clinic to teach self-cannulation to incenter patients. The observed use of this technique has helped create a comfortable environment for the patient.

Q: there anything I can do to be more successful cannulating an upper arm fi s t u l a that rolls or retracts into the tissue upon attempted cannulation? Even stretching the skin does not help much. A: access is a hemodialysis patient’s lifeline, and successful cannulation is critical to the viability of the vascular access. One of the best ways to preserve the access is to try to make every cannulation trouble-free by decreasing cannulation attempts and needle manipulation. This will lessen the chance of infiltration and damage to the intimal lining of the vessel wall of the vascular access. Problems with cannulation of upper arm accesses are common, particularly in obese patients. Because immobilization of vessels is a problem, cannulation can require multiple attempts to achieve a viable access. Cannulation can be troublesome due to a variety of reasons, including the blood vessel rolling or retracting into the surrounding tissue (Ball, 20 05). Multiple needle sticks increase the probability of vessel damage due to the development of aneurisms, infiltrations, and vessel lining damage. The number of possible access sites is limited, so it is crucial to use strategies that prolong the viability of the vascular a c c e s s .

Hemodialysis InternationalVolume 8, Issue 3 p. 306-306 Reply to letter on diffusion study Harold L Moore, Harold L Moore Professor Emeritus of Medicine MA436 Health Sciences Center University of Missouri One Hospital Drive Columbia, MO 65212, U.S.A.Search for more papers by this authorZbylut J Twardowski, Zbylut J Twardowski Professor Emeritus of Medicine MA436 Health Sciences Center University of Missouri One Hospital Drive Columbia, MO 65212, U.S.A.Search for more papers by this author Harold L Moore, Harold L Moore Professor Emeritus of Medicine MA436 Health Sciences Center University of Missouri One Hospital Drive Columbia, MO 65212, U.S.A.Search for more papers by this authorZbylut J Twardowski, Zbylut J Twardowski Professor Emeritus of Medicine MA436 Health Sciences Center University of Missouri One Hospital Drive Columbia, MO 65212, U.S.A.Search for more papers by this author First published: 30 June 2004 https://doi.org/10.1111/j.1492-7535.2004.01110.xRead the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume8, Issue3July 2004Pages 306-306 RelatedInformation

Background: The major source of catheter‐associated bacteremia is contamination of the catheter hub during connection–disconnection procedures. A new method of catheter locking has been developed wherein anticoagulant is injected first, followed by a 0.1‐mL air bubble and 0.9 mL of bactericidal solution. The anticoagulant is then located at the catheter tip and the bactericidal solution is located at the catheter hub. The air bubble prevents mixing of the two solutions. The bactericidal solution was acidified concentrated saline (ACS). The 27% saline solution has a pH of 2.0. ACS was chosen because it is theoretically harmless if injected in the amount used to lock the catheter lumens. The goals of this pilot study were to determine whether the new method of catheter locking is easy to perform with available syringes and whether eventual injection of the experimental solution is well tolerated. Methods: Ten patients were randomly assigned, either to heparin lock (5 patients, 62 treatments) or air‐bubble method (5 patients, 56 treatments). In the control group, the catheters were locked with heparin, 5000 U/mL. In the experimental group, the catheters were locked with heparin, air bubble, and ACS. Altogether, the lumens were overfilled by 0.2 mL. Results: Compared to the routine method, the experimental method required a 1‐ to 2‐min‐longer procedure time. There were no errors in proper sequence of injections into the lumina. There were no episodes of bacteremia related to hub contamination in either group. In the air‐bubble group, there was one case of bacteremia associated with purulent drainage from the exit and the same organism in both cultures. In three instances in each group, the locking solution could not be aspirated and was injected without any subjective symptoms or objective signs. Conclusion: We conclude that the air‐bubble method of locking central‐vein catheters is easy to perform. In three instances of air‐bubble and ACS injection, there were no adverse effects. A full‐scale prospective randomized study is feasible and warranted.

Background: Soft, cuffed indwelling catheters are used for hemodialysis access and intravenous infusions. The majority of these catheters are removed as a result of infection caused by contamination of the catheter hub during the connection/disconnection procedures. To prevent clot formation in the lumen, these catheters are routinely “locked” with heparin or some other anticoagulant. None of the anticoagulants commonly used as locking solutions demonstrates any significant bactericidal properties. The primary goal of this study was the development of a catheter locking method that retains anticoagulant properties at the catheter tip and bactericidal properties at the catheter hub. The second goal was to find a solution that possesses excellent bactericidal properties but is not detrimental in the event of injection into the patient's blood stream. The bactericidal properties of acidified, concentrated saline (ACS) were compared to concentrated trisodium citrate and to commonly used bactericidal agents such as povidone iodine, sodium hypochlorite, and chlorhexidine. Methods: In preliminary studies, the rate of diffusion of solutes was measured in glass tubes. In another set of experiments, the mixing of two solutions (anticoagulant and bactericide) separated by an air bubble (“air‐bubble method”) was observed in stationary and moving systems. The final series of studies compared the bactericidal properties of ACS to other bactericidal solutions mentioned above. Results: The solutions diffused swiftly in the glass tubes, and by the third day, both solutions were mixed. The air‐bubble method prevented mixing in both stationary and moving systems. The bactericidal properties of ACS were superior to all other tested solutions. Conclusions: The proposed method of catheter locking with anticoagulant at the catheter tip and ACS at the catheter hub separated by an air bubble is a promising technique and clinical studies are warranted.

Between dialyses, the catheter lumens are commonly locked with heparin (H), which does not prevent bacterial growth. Trisodium citrate (TSC) has been used as a locking agent because of its anticoagulant effects and suggested bactericidal properties. The purpose of this study was to evaluate the bactericidal properties of ACS as a potential locking agent in the air-bubble locking method (Twardowski ZJ et al. Air-bubble method of locking central-vein catheter: A pilot study. Hemodial Int. Abstracts, 2003; 7: this issue). ACS does not induce formation of resistant strains, and is harmless if a small amount (0.5–1.5 ml) is incidentally injected. Other bactericidal agents, such as Chlorhexidine (Ch), povidone iodine (PI), TSC, and sodium hypochlorite (SH) are harmful if incidentally injected. Bactericidal properties of ACS were compared to 27% NaCl, normal saline (NS) bacteriostatic NS (BNS), 1% SH, 0.057% SH, 46% TSC, 23% TSC, H 5000 units/ml, H 10,000 units/ml diluted with BNS to 5000 units/ml, 4% Ch, and 10% PI. Effects on 8 organisms were studied: S. aureus, penicillin and methicillin resistant S. aureus, S. epidermidis, K. pneumoniae, P. aeruginosa, E. coli, and C. albicans. The organisms were prepared following the manufacturers’ protocols with a final concentration of 107–108 cfu/ml for bacteria and 104–105 cfu/ml for yeast. Following standard microbiological technique, a 10-μl loop of preparation was added to 1 ml of each of the solutions. A sample of each solution was removed and plated at 0, 1, 3, 6, 24, 48, 72, and 96 hrs. All plates were subsequently counted 24 hrs after plating. Eight to eleven samples of each organism were tested on each solution. ACS, PI, 0.057% SH, and Ch, killed bacteria in 90%, 69%, 68%, and 61%, of samples immediately (at 0 hr); 100% of samples from these solutions showed no growth at 24 hrs. Only 1–5% of samples from other solutions showed no growth at 0 hr. All samples from BNS and 1% SH showed no growth at 24 hrs; samples taken from other solutions showed growth in 17–68% samples at 24 hrs. The percent of sterile samples taken from the latter solutions gradually increased with time, probably due to lack of nutrients. We conclude that ACS may be useful as a bactericidal agent for the air-bubble method of central-vein catheter locking. Bactericidal properties of 46% and 23% TSC were not confirmed in this study.

In the original peritoneal equilibration test (PET), which established standard values for membrane categorization in 1987, the dwell time of the preceding exchange was approximately 8 hours. Basing the test on an 8-hour prior exchange was convenient when almost all patients were on continuous ambulatory peritoneal dialysis (CAPD); however, many patients are now on some form of automated peritoneal dialysis (PD), and an 8-hour exchange before the PET requires a change in the dialysis schedule. Our goal in the present study was to determine whether the dialysate-to-plasma ratio (D/P) of solutes and the final dialysate to initial dialysate ratio (D/D0) of glucose in the short PET (2-hour equilibration time) are similar whether a 3-hour exchange or an 8-hour exchange precedes the test. The PETs were performed in 9 stable PD patients using 2 L of 2.5% dextrose dialysis solution (Baxter Healthcare, Deerfield, IL, U.S.A.). Before the equilibration exchange, the patients were on a randomly selected long (approximately 8-hour) or short (3-hour) dwell. During the equilibration exchange, dialysate samples were collected at 0.30, and 60 minutes of dwell time and from the drain bag (120-minute sample). Within a week, the PET was repeated in each patient after the alternate-length exchange. The values for D/P creatinine and urea and for D/D0 glucose were almost identical throughout the 2-hour PET after either the long or the short exchange. The D/P protein values tended to be higher in the PET after the long exchange. The short PET can be used for clinical purposes, and the creatinine and glucose results can be used for membrane categorization. Any dwell time between 3 and 12 hours is acceptable for the preceding exchange, and the equilibration test may be performed with either a 2-hour or a 4-hour dwell. The protein values obtained after a 3-hour prior dwell differ from those obtained after a long prior dwell. Protein values must therefore be standardized in a larger number of patients.

Background. In general, there is a good correlation between the specific gravity and osmolality of a urine sample. In certain clinical conditions, such as uncontrolled diabetes mellitus, nephrotic syndrome, after the administration of intravenous radiocontrast material or saline diuresis, dependence upon specific gravity for determining the concentrating ability will result in over- or underestimation. Methods: We studied the relationship between specific gravity and osmolality in vitro with simulated urines of varying composition. Urine samples from patients with different clinical conditions were also analyzed. Results: The in vitro curves for sodium chloride, urea, creatinine, glucose, contrast dye, and albumin were plotted (specific gravity versus osmolality). We found a linear correlation between the specific gravity and osmolality of the 6 substances that were studied and for their combinations. The urine samples obtained from patients with different clinical conditions documented that reliance on specific gravity could over- or underestimate the urine osmolality. Conclusions: We concluded that in those clinical conditions, urine osmolality should always be determined and it should not be estimated based on specific gravity.

BACKGROUND:Residual renal function (RRF) plays an important role in dialysis patients. Studies in patients on maintenance dialysis suggest that RRF is better preserved in patients receiving peritoneal dialysis (PD) vis-à-vis those receiving hemodialysis (HD). We speculated that regardless of the patient's type of therapy, the estimate obtained for the rate of decline in glomerular filtration rate (GFR) may be biased because of informative censoring associated with patient dropout. Informative censoring occurs when patients who die or transfer to another modality very early have associated with them a lower starting GFR or a higher rate of decline of GFR than patients who either complete the study or who die or transfer much later. If patient dropout is indeed related to the rate of decline in GFR and if this relationship is ignored in the analysis, then the estimate obtained of the rate of decline in GFR may be biased.METHODS:In an attempt to determine if there is a relationship between patient dropout and the decline in GFR, we reanalyzed the CANUSA data by modeling GFR as a nonlinear function of time with the rate of decline being exponential.RESULTS:This article highlights the significance of "informative censoring" when studying the decline of RRF on dialysis. The results show that for the CANUSA cohort, the mean initial GFR was significantly lower, and the rate of decline was significantly higher for patients who died or transferred to HD than for patients who were randomly censored or received a transplant. It is important to emphasize that the impact of informative censoring on previous analyses of the decline of RRF between PD versus HD is presently unclear. If bias caused by informative censoring is the same regardless of what therapy a patient is on, then conclusions from previous studies comparing the decline in GFR between PD and HD would still be valid. However, if the magnitude of the bias differs according to therapy, then additional adjustments would be needed to fairly compare the decline in GFR between PD and HD. Because this analysis is restricted to patients on PD, it would be scientifically incorrect to interpret previous studies solely on the basis of the results from this analysis.CONCLUSION:In any longitudinal study designed to estimate trends in an outcome measured over time, it is important that the analysis of the data takes into account any effect patient dropout may have on the estimated trend. This analysis demonstrates that among PD patients, both the starting GFR and the rate of decline in GFR are associated with patient dropout. Consequently, future studies aimed at estimating the rate of decline in GFR among PD patients should also account for any dependencies between dropout and GFR. Similarly, data analyzing for apparent differences in the rate of decline of GFR between PD and HD should also adjust for possible informative censoring.

Blood flow, measured by an ultrasound flowmeter, and the extent of hemolysis were assessed during a single, routine dialysis in 100 patients. Before and after the hemodialysis session, blood was drawn for measurements of haptoglobin (HPT), hemoglobin (HGB), albumin (ALB), and lactate dehydrogenase (LDH). The average values were as follows: pump speed 510 mL/ min, real blood flow 422 mL/min, arterial chamber pressure -350 mm Hg, and venous chamber pressure 279 mm Hg. Haptoglobin concentrations were higher in patients with central vein catheters compared to patients with arteriovenous access. The meaning of this finding is unclear. Mean HPT concentrations increased significantly less during hemodialysis (2.37%) than concentrations of ALB (11.3%), HGB (9.17%), and LDH (18.2%), indicating that some hemolysis is present in all dialyses. In dialyses with arterial chamber pressures more negative than -350 the median concentration of ALB (8.70%) increased significantly more than the median concentration of HGB (7.99%). This indicates significantly more hemolysis in dialyses with more negative pressures compared to those with less negative arterial chamber pressures. Median LDH increased more in dialyses with more negative prepump chamber pressures (16.19% vs 13.78%), but not significantly; however, LDH increases were significantly higher than either HGB or ALB, thus indicating significantly more hemolysis in dialyses with more negative pressures compared to those with less negative arterial chamber pressures. Erythropoietin dose was not significantly different in patients dialyzed with more or less negative arterial chamber pressures (17 645 ± 1226 U/week vs 16 308 ± 1506 U/week). We conclude that dialyses with negative arterial chamber pressures greater than -350 mm Hg cause slightly higher hemolysis than dialyses with less negative arterial chamber pressures, but this increased hemolysis is not associated with an increased requirement of erythropoietin dose. Whether this increased hemolysis is of clinical significance is uncertain.