Flexibility in peritoneal dialysis prescription: Impact on technique survival

Background:

Patient burnout is a major cause of technique failure on peritoneal dialysis (PD). Reducing the PD prescription on an individual basis, dependent upon residual kidney function (RKF), may have a role in prolonging time on PD by reducing dialysis burden. This retrospective study aimed to determine the safety and impact of flexible PD prescribing on technique and patient survival.

Methods:

All patients (186) from our centre starting PD from 1st January 2012 to 31st December 2016 were included. Data on dialysis prescription were collected for each patient from the time they had started PD, and dialysis adequacy measured regularly (3–6 monthly) using PD Adequest.

Results:

Median age at start of dialysis was 61 years. Only 49% started on PD 7 days a week and this dropped to 27% at 3 months following the first clearance test. Over 90% achieved creatinine clearance > 50 L/week/1.73 m2 up to 2 years of follow-up, with 87% achieving this standard at 3 years. Patient and technique survival at 1, 2 and 3 years were 91%, 81%, and 72%, and 89%, 87% and 78% respectively. Factors on univariate analysis affecting technique survival included increasing age (HR 0.98, p = 0.04, 95% CI (0.96–0.999)), two or more episodes of PD-associated peritonitis (HR 4.52, p = 0.00, 95% CI (1.87–10.91)) and increasing PD intensity (HR 3.30, p = 0.02, 95% CI (1.22–8.93)). After multivariate adjustment which included baseline kidney function, low PD intensity continued to be associated with better technique survival (HR 0.17, p = 0.03, 95% CI (0.03–0.85)).

Conclusion:

Tailoring the PD prescription to RKF enables days off dialysis while still maintaining recommended levels of small solute clearance. This approach reduces dialysis burden and is associated with higher technique survival.

Frequency and Causes of Discrepancy between Kt/V and Creatinine Clearance

Objective

This study examines the frequency of discrepancy between Kt/V urea and creatinine clearance (Ccr) measurements in patients on peritoneal dialysis (PD) and the reasons for this discrepancy.

Design

Nonrandomized, retrospective data analysis.

Setting

Single PD unit of a university teaching hospital.

Patients

All adult patients receiving PD at our center from January 1995 to December 1996.

Methods

Actual (a) and desired (d) body weight (BW) were used to calculate urea volume of distribution (V) and body surface area (BSA). Patients were divided into four groups based upon their total small solute clearances (Kt/V and Ccr, normalized by actual weight) and three additional groups based upon actual/desired (a/d) body weight ratio. An additional analysis was performed for the subset of anuric patients. Data collected for all patients included the following: total Kt, total Ccr, 4-hour dialysate/ plasma (D/P) creatinine, serum albumin concentration, duration of PD, actual body weight, age, and height.

Results

Twenty-three percent of the clearance measurements in our study were discrepant, defined as having values for either Kt/V or Ccr (but not both) above the accepted targets of Kt/V ≥ 2.0/wk and Ccr ≥ 60 L/wk/ 1.73 m2. Patients with both values above target are more likely to have higher residual renal function. Patients who are significantly less than BWd and patients on PD for a longer time are more likely to have adequate Kt/V but not Ccr. Furthermore, patients who are less than 90% or greater than 110% of BWd have markedly different values for Kt/V and Ccr when BWa versus BWd values are used.

Conclusions

Kt/V and Ccr values are frequently discrepant; a number of factors affect these two measurements to varying degrees, including weight, degree of residual renal function, and duration of PD.

The Effect of Technique Failure on Outcome in Black Patients on Continuous Ambulatory Peritoneal Dialysis

Background

We previously reported that, while black patients have a better patient survival than white patients on peritoneal dialysis (PD), they also have a significantly higher technique failure rate (39% vs 8%, p < 0.0001). The purpose of this study was to determine the effect of technique failure/transfer to hemodialysis (HD) on patient survival in black PD patients.

Methods

We retrospectively evaluated 137 incident black patients entering our PD program from January 1987 to December 1997. During the course of follow-up, 82 (60%) patients remained on PD (PD group) while 55 (40%) patients were permanently transferred to HD (PD–HD group). The primary outcome measured was patient survival.

Results

Average age was 49 ± 15 years, 42% were male, and 40% had diabetes mellitus. At baseline, serum creatinine was 10.8 ± 5.4 mg/dL, serum albumin 3.4 ± 0.7 g/dL, body mass index 27.3 ± 6.5 kg/m2, peritoneal transport status was high in 18% and high-average in 61%, and residual glomerular filtration rate was 3.4 ± 3.5 mL/minute. There were no significant differences in clinical features, nutritional status, peritoneal transport, residual renal function, or dialysis adequacy at baseline between the PD group and PD–HD group. While a greater proportion of patients transferring to HD had cardiac disease (53% vs 32%, p < 0.05), there were no other significant differences in 15 comorbid conditions assessed at baseline. The primary reason for transfer was peritonitis (64%) and the overall peritonitis rate in the PD–HD group was significantly higher than in the PD group (2.21 vs 1.17 episodes/patient-year, p < 0.0001). Overall follow-up was 34 ± 25 months for PD group and 44 ± 26 months for PD–HD group ( p < 0.01), with a mean time on PD prior to transfer to HD of 22 ± 18 months. During the course of follow-up, there were no significant differences between the two groups in the number of patients transplanted or deaths. Patient survival at 1, 2, and 5 years was 91%, 80%, and 57% for PD group and 96%, 92%, and 55% for PD–HD group [ p = not significant (NS)]. A risk-adjusted time-dependent Cox regression analysis resulted in an adjusted relative risk of death that was not significantly different for those who transferred from PD to HD versus those who remained on PD (relative risk 1.49; 95% confidence interval 0.77–2.89; p = NS).

Conclusions

In black patients on PD, transfer to HD is not associated with any significant difference in patient survival compared to patients remaining on PD. While a high rate of peritonitis predisposes to technique failure, we found no features at baseline predictive of patients at greatest risk to fail PD. Since technique failure does not portend a poorer prognosis, PD remains a viable option for black patients entering an end-stage renal disease program.

Peritoneal Dialysis Case Forum

The Trials and Tribulations of an Adolescent Patient with End-Stage Renal Disease

Effect of Oral Administration of Losartan, Prazosin, and Verapamil on Peritoneal Solute Transport in Continuous Ambulatory Peritoneal Dialysis Patients

Background

Several intraperitoneally administered drugs have been shown to modify transport of peritoneal solute and fluid. Fewer studies, however, have evaluated the effect of orally administered drugs. The present study was performed to evaluate the effects of oral losartan, prazosin, and verapamil on peritoneal membrane transport during a peritoneal equilibration test (PET), as well as the effects on creatinine clearance (CrCl), Kt/V urea, 24-hour protein in drained dialysate, and drained volume.

Methods

This was an open, controlled, crossover clinical trial performed in 20 patients on continuous ambulatory peritoneal dialysis. All subjects used four 2-L 1.5% glucose dialysis exchanges per day. After a 7-day washout period (without antihypertensives), they had a baseline standard PET and dialysis adequacy assessment performed. Subsequently, they were randomly allocated to receive the first of three study drugs (losartan, prazosin, and verapamil), which were administered orally for a 7-day period. Immediately after each drug period, patients had a new 3-day washout and subsequently started the next drug, until they had received each of the three drugs. On the last day of administration of each drug, patients were subjected to a new PET and adequacy of dialysis evaluation.

Results

None of the studied drugs significantly modified the peritoneal transport of creatinine, glucose, urea, sodium, potassium, or total protein as evaluated by PET. Verapamil significantly increased peritoneal CrCl [51.3 (44.3 – 53.3) vs baseline 45.8 (41.4 – 50.5) L/week/1.73 m2, p < 0.05], weekly Kt/V urea [1.75 (1.60 – 1.78) vs baseline 1.59 (1.54 – 1.73), p < 0.05], and drained dialysate volume [8.80 (8.30 – 8.96) vs baseline 8.44 (8.20 – 8.50) L/day, p < 0.05].

Conclusions

Oral administration of losartan, prazosin, and verapamil did not modify the peritoneal transport of solutes during a 4-hour PET. Oral verapamil significantly increased CrCl, Kt/V urea, and 24-hour drained dialysate volume. It is most likely that verapamil increases peritoneal (hydraulic) conductivity, and then net ultrafiltration volume and convective transport of urea, creatinine, and protein. Verapamil could be considered as an alternative in patients requiring increased dialysis dose and/or ultrafiltration.

Association of Alternative Approaches to Normalizing Peritoneal Dialysis Clearance with Mortality and Technique Failure: A Retrospective Analysis Using the United States Renal Data System-Dialysis Morbidity and Mortality Study, Wave 2

♦ BACKGROUND: Total body water (V) is an imprecise metric for normalization of dialytic urea clearance (Kt). This poses a risk of early mortality/technique failure (TF). We examined differences in the distribution of peritoneal Kt/V when V was calculated with actual weight (AW), ideal weight (IW), and adjusted weight (ADW). We also examined the associations of these Kt/V measurements, Kt/body surface area (BSA), and non-normalized Kt with mortality and TF. ♦ METHODS: This is a retrospective cohort study of 534 incident peritoneal dialysis (PD) patients from the Dialysis Morbidity and Mortality Study Wave 2 linked with United States Renal Data System through 2010. Using Cox-proportional hazard models, we examined the relationship of several normalization strategies for peritoneal urea clearance, including Kt/VAW, Kt/VIW, Kt/VADW, Kt/BSA, and non-normalized Kt, with the outcomes of mortality and TF. Harrell's c-statistics were used to assess the relative predictive ability of clearance metrics for mortality and TF. The distributions of Kt/VAW, KT/VIW, and KT/VADW were compared within and between body mass index (BMI) strata. ♦ RESULTS: Median patient age: 59 (54% male; 72% white; 91% continuous ambulatory PD [CAPD]). Median 24-hour urine volume: 700 mL; median estimated glomerular filtration rate (eGFR) at initiation: 7.15 mL/min/1.73 m2. Technique failure and transplant-censored mortality at 5 years: 37%. Death and transplant-censored TF at 5 years: 60%. There were no significant differences in initial eGFR and 24-hour urine volume across BMI strata. There were statistically significant differences in each Kt/V calculation within the underweight, overweight, and obese strata. After adjustment, there were no significant differences in the hazard ratios (HRs) for TF/mortality for each clearance calculation. Harrell's c-statistics for mortality for each clearance calculation were 0.78, and for TF, 0.60 - 0.61. ♦ CONCLUSIONS: Peritoneal urea clearances are sensitive to subtle changes in the estimation of V. However, there were no detectable significant associations of Kt/VAW, Kt/VIW, Kt/VADW, Kt/BSA, or Kt with TF or mortality.

Peritoneal Dialysis in Brazil: Twenty-Five Years of Experience in a Single Center

Objectives

To evaluate patient and technique survival and to provide an analysis of peritoneal dialysis (PD)-related peritonitis in 25 years of experience in a single center.

Study Design

Retrospective study of incident patients on PD from July 1980 to July 2005.

Setting

Single, university based, Brazilian dialysis program.

Patients

680 patients were analyzed in our study from July 1980 to July 2005, with a cumulative experience of 15303 patient-months. All patients over 15 years of age entering the dialysis program were included in the study. Patients with less than 30 days of follow-up were excluded. Biochemical and demographic variables, peritonitis episodes, and patient and technique survival were analyzed.

Results

Mean age at start of PD was 53 ± 16 years; diabetic nephropathy was the main cause of chronic kidney disease. Cardiovascular disease was the main cause of death (44%); peritonitis was responsible for 16% of fatal events. The predictors of death in our study were diabetes [relative risk (RR) 1.23, p < 0.01], advanced age (RR 1.58, p < 0.001), low serum albumin level (RR 1.25, p < 0.01), and low serum phosphate level (RR 1.39, p < 0.001) upon starting PD. There were 1048 cases of peritonitis over the 25-year period, with a significant reduction in incidence after the introduction of the double-bag system. The number of incident PD patients originating from hemodialysis increased threefold over the observation period ( p < 0.001), with a similar increase in comorbidities over time.

Conclusion

In the largest single-center report of PD experience in Latin America, we describe the overall rate and trends over time of peritonitis as well as patient and technique survival, which are similar to previous reports. Significant changes in peritonitis rates and causative organisms as well as a significant time-dependent increase in high-risk patients starting PD were observed.

Discrepancies between adequacy goals in peritoneal dialysis: role of gender

BACKGROUND

The National Kidney Foundation-Dialysis Outcome Quality Initiative (NKF-DOQI) recommends a weekly creatinine clearance (CrCl) of 60 L/wk/1.73 m2 or greater and a Kt/V of 2.0 or greater as peritoneal dialysis (PD) adequacy standards. It has been described that approximately one quarter of patients may have discrepancies between these goals. The purpose of this study is to identify associated factors in patients reaching both criteria, none, or only weekly Kt/V, where K is clearance, t is time, and V is volume.

METHODS

We studied 64 patients and their adequacy results in a cross-sectional analysis. Patients were divided in three groups. Group 1 reached both weekly Kt/V and CrCl criteria. Group 2 did not reach either criteria. Group 3 reached only the weekly Kt/V criterion. A new weekly Kt/V also was calculated, assigning to all patients a male V. One patient who met only the CrCl criterion was excluded.

RESULTS

Groups 2 and 3 had significantly less residual renal function (RRF) than group 1 (residual CrCl, 5.50 and 1.33 versus 37.3 L/wk/1.73 m2, respectively; P < 0.001). Other differences, such as age, weight, peritoneal membrane transport, nutritional parameters, or number of patients with diabetes, were not significantly different. Group 3 made up 19% of patients and was predominantly females. Conversely, group 2 was predominantly males. Using a male V, we obtained a weekly Kt/V below the NKF-DOQI recommendations for group 3 (1.9 versus 2.2; P < 0.05).

CONCLUSION

Conservation of RRF was the main factor in reaching both PD adequacy criteria. Discrepancies were frequent, accounting for 19% of our population. Female gender explained why patients reached weekly Kt/V only. This difference disappeared when we calculated Kt/V using a male V.

Peritoneal Function and Adequacy Calculations: Current Programs versus PD Adequest 2.0

Objective

Our current programs (CPs) were compared to PD Adequest 2.0 (PD-A) for calculations of peritoneal membrane transport and dialysis adequacy.

Design

Thirty peritoneal equilibration tests (PETs) and 24-hour balances (24hBs) were conducted and calculated using our CPs and PD-A.

Patients and Methods

Thirty hospital-controlled peritoneal dialysis (PD) patients were studied. The inclusion of correction factors (for glucose or plasmatic water) and of residual volume, and the use of 3 or 6 peritoneal samples were analyzed to discover the differences between programs. The main outcome measures were peritoneal permeability and adequacy parameters, evaluated by Student t-test (mean and paired comparisons) and linear regression for correlation.

Results

No significant differences were found in D/P values for small solutes. At the first step, mass transfer area coefficient (MTAC) urea and MTAC creatinine were significantly higher in DP-A than in CP, but MTAC glucose did not differ. The causes of differences were: ( 1 ) inclusion of a correction factor for aqueous plasmatic concentration of small solutes in CP; ( 2 ) lack of inclusion of residual volume in peritoneal volumes in CP; and ( 3 ) use of 6 peritoneal samples in CP versus 3 in PD-A. At the second step, when the input data were made equivalent for both programs, the differences disappeared for MTAC urea, creatinine, and glucose (mean comparison), but creatinine and glucose remained different by paired comparison. Similar results were obtained when a correction for plasmatic aqueous concentration was applied to the data in both programs [MTAC urea: 22.60 ± 4.27 mL/min (CP) vs 22.43 ± 4.61 mL/min (PD-A), nonsignificant, r = 0.97; MTAC creatinine: 9.76 ± 3.83 mL/min (CP) vs 10.61 ± 3.07 mL/min (PD-A), nonsignificant, r = 0.98; MTAC glucose: 13.30 ± 3.12 mL/min (CP) vs 11.87 ± 3.41 mL/min (PD-A), nonsignificant, r = 0.92]. Creatinine and glucose were different by paired t-test. No significant differences were found in Kt/V and urea generation rate. Weekly creatinine clearance [WCCr: 70.71±16.71 L (CP) versus 79.33±18.73 L (PD-A), p < 0.001] and creatinine generation rate [CrGR: 0.56 ± 0.18 mg/min (CP) versus 0.61±0.19 mg/min (PD-A), p < 0.001) were significantly higher in PD-A than in CP owing to the lack of creatinine correction according to glucose concentration in the PD-A adequacy program. Finally, normalized protein nitrogen appearance according to Bergström [1.09 ± 0.20 g/kg/d (CP) versus 1.03 ± 0.21 g/kg/d (PD-A), p = 0.01] was different owing to the different algorithms and normalization method: standardized body weight in CP and actual body weight in PD-A.

Conclusions

Provided that equivalent data are used, PD-A and CP yield similar results. The PD-A program needs external correction of data input: ( 1 ) for plasmatic water concentration in MTAC calculations, and ( 2 ) for peritoneal glucose interference with creatinine analysis (Jaffé method) in WCCr and CrGR calculations; otherwise, it may give falsely optimistic results.

Patient survival among incident peritoneal dialysis and hemodialysis patients in an urban setting

We retrospectively evaluated 432 patients (336 black; 78%; and 96 white; 22%) incident to our peritoneal dialysis (PD; 195 patients; 45%) and hemodialysis (HD; 237 patients; 55%) programs from January 1987 to December 1997 who survived their first 90 days of dialysis therapy. Black patients comprised 70% of the PD and 84% of the HD patients (P: < 0.01). PD patients were more often men and younger than HD patients and less often had diabetes (40% versus 56% of HD patients; P: < 0.01) and cardiac disease (44% versus 58% of HD patients; P: < 0.01) than HD patients. Adjusting for baseline clinical and comorbid features, patient survival was determined by Cox regression analysis. Survival was better on PD therapy overall (relative risk [RR] for PD versus HD, 0.80; 1-, 2-, and 5-year survival rates, 90%, 77%, and 43% on PD versus 88%, 72%, and 35% on HD, respectively; P: = 0.21) and among black patients (RR for PD versus HD, 0.69; 1-, 2-, and 5-year survival rates, 92%, 80%, and 52% on PD versus 88%, 74%, and 40% on HD, respectively; P: = 0.09), but these were not statistically significant. The RR for PD versus HD was 1.08 for white patients (1-, 2-, and 5-year survival rates, 82%, 61%, and 23% for PD versus 82%, 62%, and 24% for HD; P: = 0.79). Significant predictors of mortality were race (RR for whites versus blacks, 1.51), age (RR, 1.03), cardiac disease (RR, 1.57), baseline albumin level (RR, 0.60), baseline serum creatinine level (RR, 0.91), baseline blood urea nitrogen level (RR, 1.01), and baseline weight (RR, 0.98). In conclusion, patient survival on dialysis therapy is significantly better for black patients and for patients entering dialysis with signs of adequate nutrition (increased weight and creatinine and albumin levels) and without evidence of cardiac disease. In an urban dialysis program, we find that adjusted patient survival on PD equals or is better than that on HD therapy, particularly among black patients, making PD a viable alternative to HD in our patient population.

Adequacy of peritoneal dialysis

The National Kidney Foundation-Dialysis Outcomes Quality Initiatives guidelines have standardized many aspects of treating end-stage renal disease patients with peritoneal dialysis in an attempt to improve overall patient outcome. While recommending certain total solute clearance goals, the guidelines have also pointed out deficiencies in our knowledge base and precipitated many controversies. Some of these controversies have been resolved while others may have been interpreted wrongly, unnecessarily resulting in transfer of patients from peritoneal dialysis to hemodialysis due to "failure to meet adequacy targets" even when doing well clinically. This report reviews the rationale for the original guidelines and their subsequent modification. It also outlines a rational approach toward prescription modification based on peritoneal physiology. Specific solute clearance target goals discussed are the modifications for continuous ambulatory peritoneal dialysis (CAPD) and cycler peritoneal dialysis (CCPD), and a review of what solute clearance targets subsequent guidelines from other countries have used. Some examples are as follows: new guidelines suggest that solute clearance goals for creatine clearance should differ for low and low-average transporters than for high and high-average transporters (weekly clearance of 50 and 60 1/1.73 m(2), respectively) while Kt/V targets remain unchanged. Also discussed is the rationale for having the same target for patients on CCPD with a mid-day exchange as those for patients on CAPD. We are also reminded that solute clearance is only one aspect of "adequate" dialysis-blood pressure and volume control are equally important, and ways to maintain euvolemia and blood pressure control are discussed in the context of prescription management.

Racial differences in survival in an urban peritoneal dialysis program

We retrospectively evaluated 233 incident patients (61% black, 27% white, and 12% Hispanic/Asian) to our peritoneal dialysis (PD) program from January 1987 to September 1997 to identify any possible racial differences in patient survival. Information collected included clinical features, comorbid conditions, nutritional status, and dialysis dose at initiation of dialysis. The average age was 52 +/- 16 (SD) years, and 49% were men. Diabetes mellitus was present in 41% of patients. Overall follow-up was 31 +/- 24 (median 26) months during which time 21% of patients underwent transplant, 29% of patients transferred to hemodialysis (HD), and 42% of patients died. The Cox proportional hazards analysis, based on intent-to-treat, identified age (RR: 1.03), race (RR: 2.35, white versus black), cardiac disease (RR: 1.97), and serum albumin (RR: 0. 44) to independently predict mortality. Further analysis was performed based on diabetic status, and the analysis identified age (RR: 1.06), race (RR: 2.45, white versus black), and peripheral vascular disease (RR: 2.88) as predictors of mortality in diabetic patients. In nondiabetic patients, age (RR: 1.03), race (RR: 2.24, white versus black), cardiac disease (RR: 2.48), cerebrovascular disease (RR: 3.17), and serum albumin (RR: 0.39) were significant predictors of mortality. The significance of race persisted even after adjusting patients transferring to hemodialysis. The adjusted patient survival at 1, 2, and 5 years was 94%, 87% and 53% for black patients, and 86%, 72%, and 23% for white patients. The adjusted patient survival in diabetics at 1, 2, and 5 years was 92%, 79%, and 37% for black patients, and 82%, 56%, and 9% for white patients. The adjusted patient survival in nondiabetics at 1, 2, and 5 years was 94%, 91%, and 63% for black patients, and 88%, 82%, and 35% for white patients. In conclusion, long-term patient survival is better for black patients than white patients in our peritoneal dialysis program. Peritoneal dialysis should be considered a viable dialytic option for black patients entering an end-stage renal disease program.

Evaluation of the PD Adequest Program in Japanese Patients on Peritoneal Dialysis

To perform adequate peritoneal dialysis, it is necessary to individualize the dialysis regimen. PD Adequest is a software program based on the three-pore model that can be used to predict solute clearance and ultrafiltration volume during peritoneal dialysis. We evaluated the ability of this program to predict the solute clearance and ultrafiltration volume in Japanese patients on peritoneal dialysis. The weekly creatinine clearance and weekly urea Kt/V were determined in 45 patients. The PD Adequest was used to simulate their current dialysis regimens and the predicted values of these parameters were calculated. Strong positive correlations were obtained between the actual and predicted weekly creatinine clearance (r=0.993) and weekly urea Kt/V (r=0.991). In conclusion, this program is potentially useful for designing peritoneal dialysis regimens in Japanese patients, even though they have a smaller body mass than Canadians and Americans for whom it was designed.

Peritoneal dialysis adequacy: a model to assess feasibility with various modalities

BACKGROUND

The current standard of adequacy for peritoneal dialysis (PD) is to provide a weekly normalized urea clearance (Kt/V) of 2.0 or more and a creatinine clearance (CCr) of 60 liter/1.73 m2 or more. As native renal function is lost, it is important to determine the effectiveness of the available therapeutic modalities in achieving these goals.

METHODS

A model to assess our ability to provide a weekly Kt/Vurea of 2.0 or more and a CCr of 60 liter/1.73 m2 or more to anuric patients undergoing continuous ambulatory PD (CAPD) and automated PD (PD Plus) was developed. The body surface area (BSA) distribution was obtained from 38,768 patients undergoing dialysis during January 1997. The distribution of peritoneal transport rates (PTRs) was obtained from 2531 peritoneal equilibration tests performed during 1996. The weekly Kpt/Vurea was calculated for the various PTR groups and the range of BSA with four PD prescriptions: CAPD 8 liters, CAPD 10 liters, PD Plus 12 liters, and PD Plus 15 liters, using a previously validated kinetic program (PackPD).

RESULTS

The predicted percentage of patients capable of achieving the adequacy goals for Kt/V and CCr, respectively, were 24.8 and 11. 2 for CAPD 8 liters, 54.2 and 33.0 for CAPD 10 liters, 77.8 and 54.9 for PD Plus 12 liters, and 93.2 and 72.9 for PD Plus 15 liters.

CONCLUSIONS

Most patients can attain the current adequacy standards of therapy with automated PD, but few (less than 25%) can do so with standard CAPD in the absence of residual renal function.

Trends in clinical indicators of care for adult peritoneal dialysis patients in the United States from 1995 to 1997. ESRD Core Indicators Workgroup

BACKGROUND

This article describes the changes in four core indicator variables: dialysis adequacy, hematocrit, serum albumin, and blood pressure in peritoneal dialysis CAPD and cycler patients over a three-year period.

METHODS

A national random sample of adult peritoneal dialysis patients in the United States was drawn each study period. Clinical data abstraction forms were completed by facility staff for patients selected for the sample, returned to the respective network, then forwarded to the Health Care Financing Administration for analysis.

RESULTS

The mean weekly Kt/V urea for CAPD patients increased from 1.91 in 1995 to 2.12 in 1997 (P < 0.001) and for cycler patients, from 2.12 in 1996 to 2.24 in 1997 (P < 0.05). The mean weekly creatinine clearance for CAPD patients increased from 61.48 liter/week/1.73 m2 in 1995 to 65.84 liter/week/1.73 m2 in 1997 (P < 0.05). For cycler patients, it increased from 63.37 liter/week/1.73 m2 in 1996 to 67.45 liter/week/1.73 m2 in 1997 (P < 0.05). Despite this increase in adequacy values, less than 40% of peritoneal dialysis patients in 1997 had weekly Kt/V urea or creatinine clearance values that met subsequently published National Kidney Foundation's Dialysis Outcomes Quality Initiative (DOQI) guidelines. These data suggest that the dialysis prescription may not be adequately modified to compensate for increased body weight and for decreased residual renal function as years on dialysis increase. The average hematocrit value increased modestly in both CAPD and cycler patients from 1995 to 1997, and the number of patients with a hematocrit of less than 25% decreased from 6% in 1995 to 1.4% in 1997 (P < 0.001). Both serum albumin values and systolic and diastolic blood pressure values were essentially unchanged during the three-year period of observation.

CONCLUSIONS

Despite improvements in dialysis adequacy and hematocrit values, there remains much room for improvement in these core indicator values.

Optimal care of the pediatric end-stage renal disease patient on dialysis

This manuscript is an effort on behalf of the American Society of Pediatric Nephrology to provide recommendations designed to optimize the clinical care of pediatric patients with end-stage renal disease (ESRD). Although many of the recommendations are evidenced-based with the supporting data being derived from a variety of sources, including patient registries, others are opinion-based and derived from the combined clinical experience of the authors. In all cases, it is recommended that the decision to initiate dialysis should be made only after an assessment of a combination of biochemical and clinical characteristics. Irrespective of the choice of dialysis modality (hemodialysis v peritoneal dialysis), dialysis efficacy should be measured regularly, and the dialysis prescription should be designed to achieve target clearances. Attention to dialysis adequacy, control of osteodystrophy, nutrition, and correction of anemia is mandatory, because all may influence patient outcome in terms of growth, cognitive development, and school performance. Finally, the availability of a multidisciplinary team of pediatric specialists is desirable to provide all facets of pediatric ESRD care, including renal transplantation, in an optimal manner. Future clinical research efforts intended to address topics such as dialysis adequacy, anemia management, and growth should be encouraged.

An evidence-based approach to earlier initiation of dialysis

The objective was to review evidence addressing the optimal time to initiate dialysis treatment. The database was derived from an evidence-based review of the medical literature and from the Canada-United States peritoneal dialysis study. The publications were divided into (1) those addressing the clinical impact of early versus late referral to a dialysis program; (2) those evaluating the association between residual renal function at initiation of dialysis and the concurrent nutritional status; (3) those evaluating the association between residual renal function at initiation of dialysis and subsequent clinical outcomes, including patient survival. There were five studies evaluating early versus late referral, three cohort design and two case-control design. Late referrals had worse outcomes than early referrals. The former had more serious comorbidity and many had been noncompliant with follow-up. The latter were more likely to have hereditary renal disease. Renal function was slightly worse at initiation among those referred late. Three studies addressed the association between renal function at initiation of dialysis and concurrent nutritional status. Two showed decreased protein intake with diminished glomerular filtration rate (GFR). Poor nutritional status is associated with decreased patient survival among both incident and prevalent dialysis patients. The third study reported excellent patient survival among patients with late initiation of dialysis. These patients had received a supplemented low-protein diet and were not malnourished at initiation of dialysis. Three groups have studied the association between GFR at initiation of dialysis and clinical outcomes. Decreased GFR at initiation of dialysis is associated with a increased probability of hospitalization and death. None of these studies has used the rigorous randomized clinical trial design, and they are therefore subject to bias. Referral time bias, comorbidity, patient compliance, and starting time bias are potential confounders. A randomized clinical trial is required to resolve this important issue. However, there is sufficient evidence to justify initiation of dialysis at a Ccr of 9 to 14 mL/min if there is any clinical or laboratory evidence of malnutrition.