Impact of dialysis adequacy on the mortality and morbidity of anuric Chinese patients receiving continuous ambulatory peritoneal dialysis

Dialysis adequacy has a major impact on the outcome of continuous ambulatory peritoneal dialysis (CAPD) patients. However, most studies on peritoneal dialysis adequacy have focused on patients with significant residual renal function. The present study examined the effect of dialysis adequacy on anuric CAPD patients. A single-center prospective observational study on 140 anuric CAPD patients was performed. These patients were followed for 22.0 +/- 11.9 mo. Dialysis adequacy and nutritional indices, including Kt/V, creatinine clearance (CCr), protein equivalent nitrogen appearance, percentage of lean body mass, and serum albumin level were monitored. Clinical outcomes included actuarial patient survival, technique survival, and duration of hospitalization. In the study population, 64 were male, 36 (25.7%) were diabetic, and 59 (42.1%) were treated with 6 L exchanges per day. The body weight was 59.2 +/- 10.2 kg. Average Kt/V was 1.72 +/- 0.31, and CCr was 43.7 +/- 11.5 L/wk per 1.73m(2). Two-yr patient survival was 68.8%, and technique survival was 61.4%. Multivariate analysis showed that DM, duration of dialysis before enrollment, serum albumin, and index of dialysis adequacy (Kt/V or CCr) were independent factors of both patient survival and technique survival. It was estimated that for two patients who differed only in weekly Kt/V, a 0.1 higher value was associated with a 6% decrease in the RR of death (P: < 0.05; 95% confidence interval, 0.92 to 0.99). Serum albumin and CCr were the only independent factors that predicted hospitalization. It was found that even when there is no residual renal function, higher dialysis dosage is associated with better actuarial patient survival, better technique survival, and shorter hospitalization. Dialysis adequacy has a significant impact on the clinical outcome of CAPD patients, and the beneficial effect is preserved in anuric patients as well as in an ethnic group that has a low overall mortality.     

腹膜转运和营养状况在腹透充分性中的评价

持续不卧床腹膜透析(CAPD)患者普遍存在营养不良状态,本研究探讨腹膜转运特性对CAPD患者营养状况的影响,并分析两者在透析充分性判定中的地位。     

Dialysis adequacy in Chinese anuric peritoneal dialysis patients

Purpose

We aimed in this study to explore how lower-protein diet would affect dialysis adequacy in anuric peritoneal dialysis (PD) patients.

Methods

Patients’ demographic features were collected, namely age, gender, weight, height, underlying renal disease, and time on PD. Urea kinetic model was used to assess solute clearance. A consecutive 3-day dietary record was collected to evaluate dietary protein intake (DPI), and normalized protein nitrogen appearance (nPNA) was also calculated to reflect protein intake. Blood samples were collected to measure hemoglobin and biochemistry. Patient’s nutritional status was assessed by biochemistry, handgrip strength, and subjective global assessment (SGA). Body fluid distribution was measured by body composition monitor.

Results

Patients were 60.8 ± 14.92 years old, and the time on PD was 40.15 ± 22.90 months. Daily prescribed dialysis dose was 7,178 ± 1,326 mL. Kt/V was 1.6 ± 0.32. DPI was 0.8 ± 0.25 g/kg/day. nPNA was 0.9 ± 0.21 g/kg/day. Serum albumin was 39.42 ± 4.83 g/L. Prevalence of malnutrition (assessed by SGA) was 20.2 %. Serum phosphate and serum bicarbonate were 1.68 ± 0.47 and 27.16 ± 3.49 mmol/L, respectively. Systolic blood pressure and diastolic blood pressure were 123.4 ± 20.0 and 74.2 ± 12.6 mmHg, respectively. Patients with nPNA less than 0.6 had significantly lower serum albumin concentrations than the average, and patients with nPNA more than 1.2 g/kg/day had significantly higher levels of serum phosphate and serum urea than the average.

Conclusions

Our study suggested that anuric PD patients could achieve adequate dialysis even under lower solute clearance. And lower-protein diet contributed largely to adequate dialysis in these patients.     

腹膜透析患者血清铁蛋白水平与微炎症及透析效果相关性分析

目的分析腹膜透析患者血清铁蛋白与C反应蛋白(CRP)之间的相关性,探讨血清铁蛋白对腹膜透析效果的影响。 方法回顾性分析2009年6月至2015年7月在广西医科大学第一附属医院腹膜透析中心规律随诊的腹膜透析患者120例,根据血清铁蛋白浓度将其分成三组,Ⅰ组：男性患者血清铁蛋白≤200 μg/L或女性患者血清铁蛋白≤150 μg/L;Ⅱ组：男性患者血清铁蛋白浓度为200～500 μg/L或女性患者150～500 μg/L;Ⅲ组：血清铁蛋白≥500 μg/L,将三组的临床资料进行分析。根据CRP值,将120例患者分为A组(CRP ≤8 mg/L)和B组(CRP > 8 mg/L),比较两组间血清铁、转铁蛋白饱和度、总铁结合力和血红蛋白水平差异。血清铁蛋白与各相应临床指标进行相关性分析。采用SPSS 16.0统计学软件进行数据分析。 结果(1)与Ⅰ组及Ⅱ组比较,Ⅲ组C反应蛋白水平显著升高,血红蛋白及Kt/V值均低于Ⅰ组及Ⅱ组(P<0.05),Ⅰ组与Ⅱ组比较无显著性差异(P>0.05)。(2)Ⅰ组总铁结合力明显高于Ⅱ组和Ⅲ组(P<0.05),Ⅱ组与Ⅲ组比较无显著性差异(P>0.05)。(3)相关性分析提示血清铁蛋白与血红蛋白及总铁蛋白结合力呈负相关(r＝－0.194,r＝－0.298;P<0.05),与血尿素氮、年龄及C反应蛋白呈正相关(r＝0.234,r＝0.238,r＝0.203;P<0.05)。(4)与A组比较,B组患者血清铁蛋白水平显著升高(t＝2.271, P<0.05),两组间总铁结合力、转铁蛋白饱和度及血红蛋白无显著性差异(t＝0.391,t＝0.371, t＝0.835; P>0.05)。 结论腹膜透析患者血清铁蛋白水平受微炎症状态的影响,高浓度的血清铁蛋白可影响腹膜透析患者的透析充分性,应该联合年龄、转铁蛋白饱和度、血红蛋白及CRP等指标,正确的判断患者缺铁情况。     

Comments on adequacy, nutrition and survival with peritoneal dialysis and haemodialysis

Summary: This paper summarizes the status of the worldwide peritoneal dialysis population at the end of 1994. Relative mortality risks on peritoneal dialysis and haemodialysis are compared. Clearance targets for continuous ambulatory peritoneal dialysis are discussed.     

Inotropic support and peritoneal dialysis adequacy in neonates after cardiac surgery

We describe the impact of cardiovascular pharmacologic support on peritoneal dialysis adequacy in 20 neonates who required postoperative renal replacement therapy following cardiopulmonary bypass exposure. Peritoneal dialysis was administered for 2.5 (2) days. Peritoneal dialysis creatinine clearance was 3.4 (2.1) ml/min/1.73 m(2) and ultrafiltration rate was 9.75 (10) ml/h. Residual creatinine clearance was 31 (26) ml/min/1.73 m(2). Peritoneal dialysis creatinine clearance appeared to be a function of dialysate flow up to 100 ml/h. No correlation was present between inotropes and vasopressors infusion and peritoneal dialysis creatinine clearance/ultrafiltration rate. LDH clearance was 0.59 (0.85) ml/min/1.73 m(2) and it did not appear to have a correlation with dialysate flow. Patients in-hospital mortality was 20%, significantly higher than overall neonatal population admitted to our ICU (4.8%, P=0.02). Peritoneal dialysis in neonates allows optimal ultrafiltration rate and adequate small solute clearance, irrespective of hemodynamic status or vasopressor support.     

Defining peritoneal dialysis adequacy: Kt/Vurea revisited

BACKGROUND: Although adequate peritoneal dialysis is not well defined, Kt/Vurea has been used as an index, and various values have been proposed. However, conflicting evidence existed regarding the appropriateness of using Kt/Vurea to define dialysis adequacy and its optimal value. Therefore, the present study performed a theoretical analysis on whether we should use Kt/Vurea to define peritoneal dialysis adequacy and what the optimal value should be. METHODS: The three-pore model was applied to evaluate the transport patterns of different molecular weight solutes and fluid. Optimal Kt/Vurea value was estimated based on urea kinetics and nitrogen balance. RESULTS: The removal pattern of small solute, middle and large molecules, and fluid and sodium are quite different. Depending on the dwell time, higher urea removal does not necessarily mean higher sodium, fluid, and other molecular weight solute removals. To reach nitrogen balance, the dialysis doses and therefore Kt/Vurea values varied with different dietary protein intakes in a patient with a given weight and residual renal function. CONCLUSION: This study shows that Kt/Vurea in peritoneal dialysis cannot represent the removal of other solutes and fluid, indicating that Kt/Vurea alone should not be used as a sole indicator of peritoneal dialysis adequacy. The results also show that optimal Kt/Vurea cannot be a fixed value, but varies according to individual dietary protein intake and tolerable blood urea level.     

The adequacy of laparoscopy for continuous ambulatory peritoneal dialysis procedures

The aim of this study was to determine the safety and efficacy of diagnostic/therapeutic laparoscopy in the management of peritoneal Tenchoff catheter placement in end-stage renal disease patients who had previous abdominal surgery and malfunctioning peritoneal dialysis catheters. From 1999 to 2004, 16 videolaparoscopic procedures were performed in 16 patients who had previous laparotomies. Laparoscopy was performed before peritoneal catheter placement in seven (group 1) and in 9 patients with peritoneal dialysis catheters in place, laparoscopy was performed for the management of catheter dysfunction (group 2). All laparoscopic procedures were performed under general anesthesia. The mean follow-up was 31.5 (range, 11 to 60) months. In group 1, six patients (85.7%), and in group 2, seven patients (77.7%) are still on peritoneal dialysis. Laparoscopy resulted in the placement/salvage of peritoneal dialysis catheter dysfunction. Placement of catheter was accomplished in patients who would have been previously designated as unsuitable candidates. Laparoscopy is a useful tool in every step of a peritoneal dialysis program.     

Incremental peritoneal dialysis: effects on the choice of dialysis modality, residual renal function and adequacy

There is still disagreement on whether peritoneal dialysis (PD) should begin with a full dose (Full_Dial) or with incremental doses (Incr_Dial) to compensate for the amount of Kt/V no longer supplied by the residual renal function (RRF). The aim of this study is to assess the effects of an Incr_Dial protocol on the choice of dialysis modality, RRF, and adequacy. The Incr_Dial protocol in our center is as follows: for patients with a glomerular filtration rate (GFR)>5 ml min(-1), PD is initiated with two exchanges per day (continuous ambulatory PD (CAPD)) or four sessions per week (ambulatory PD (APD)); and hemodialysis (HD) is initiated with two sessions per week. The PD dose is then increased in proportion to the reduction in the GFR as follows: GFR< or =5 and >3 ml min(-1)=3 CAPD exchanges or five APD sessions; GFR <3 ml min(-1)=full dialysis dose (Full_Dial). The effects of the Incr_Dial protocol on the choice of dialysis modality were assessed on 87 patients (pts) (age: 69.3+/-13.1 years) who initiated dialysis between 1 January 2004 and 31 May 2007. The effects of Incr_Dial on RRF and dialytic adequacy were assessed in 11 pts treated with two CAPD exchanges per day for a total of 106 months (mean+/-s.d. 9.7+/-6.5), and then treated with three CAPD exchanges per day for an additional 105 months (9.4+/-8.3). The use of Incr_Dial determined the choice of PD in 27 of 44 pts (61.4%) without indications or contraindications to HD or PD. CAPD was chosen by 20 of these pts (74.1%), whereas APD was preferred by 6 of the 8 pts switched from Incr_Dial to Full_Dial. During Incr_Dial, a significant reduction in the loss of GFR of 2.4+/-3.1 ml min(-1) year(-1) was observed when compared to the pre-dialysis period. Incr_Dial allowed for adequate clearance, as confirmed by the Kt/V (2.07+/-0.2), protein nitrogen appearance (1.17+/-0.13), and biochemical parameters. Ultrafiltration (UF) with icodextrin (772+/-166 ml per exchange) provided a daily UF of 517+/-296 ml day(-1) and remained unchanged when the duration of the dwell time increased significantly from 12.3+/-1.4 to 17.5+/-2.6 h.     

Dialysis adequacy and homocyst(e)ine concentrations in peritoneal dialysis patients.

INTRODUCTION: Determinants of hyperhomocysteinaemia in peritoneal dialysis patients have been recently reported but there is still conflicting data on the influence of dialysis adequacy on homocysteine (Hcy). METHODS: We studied 46 consecutive new continuous ambulatory peritoneal dialysis (CAPD) patients to determine the variation of Hcy before and 1 and 6 months after dialysis. The variation in Hcy was analysed with respect to dialysis adequacy, factors known to influence its metabolism, and Hcy peritoneal clearance. RESULTS: Hcy was 31.9+/-9 micromol/l before dialysis. It was significantly higher before dialysis than 1 month after the onset of PD (31.9+/-9 micromol/l vs 23.2+/-6.9 micromol/l, P < 0.0005). Weekly PD Hcy clearance was 14.3+/-5.4 1. There was no relationship between pre-dialysis Hcy and 1 month post-dialysis Hcy (r=0.176, P=0.15). There was a strong relationship between PD Hcy clearance and both PD creatinine clearance (r=0.502, P<0.005) and Kt/V (r=0.42, P<0.005). There was no relationship between Hcy and PD creatinine clearance (r= -0.221, P=0.11). In contrast, the decrease in tHcy at 1 month was related to PD Hcy clearance (r=0.487, P<0.01), to PD creatinine clearance (r= 0.349, P<0.02) and to Kt/V (r=0.32, P<0.02). Multivariate analysis confirmed the relationship between the decrease in Hcy and dialysis adequacy. Eleven patients (24%) experienced arteriosclerotic complications. Fasting Hcy concentrations in this population were significantly higher before and 1 month-post-dialysis than in patients without cardiovascular complications. CONCLUSIONS: We observed a significant and prolonged reduction in Hcy concentrations by peritoneal dialysis in end-stage renal disease patients. The decrease in Hcy concentration was positively related to dialysis adequacy. This study suggests the possibility that dialysis adequacy may influence arteriosclerotic outcomes through an Hcy-lowering effect.     

腹膜透析初透剂量对患者残余肾功能的影响

目的 探讨腹膜透析（腹透）初透剂量对患者残余肾功能的影响。 方法 追踪观察我院3个月内连续门诊随访的178例开始腹透的患者,测定24 h尿量。根据透析第1、3个月尿量的变化分为少尿组（LU,97例）、尿量减少组（DU,19例）、尿量正常组（NU,62例）,记录并分析其透析剂量、腹透液葡萄糖含量、超滤量、尿素清除指数（Kt/V）、体质量、水肿程度及尿量变化等的相关性。 结果 3组患者的年龄和性别比例差异无统计学意义。透析1个月后,DU组的体质量和水肿程度大于LU和NU组（P < 0.05）;腹透液总入量、腹透液葡萄糖含量、超滤量、残余肾尿素清除指数Kt/V（rKt/V）高于LU组,与NU组差异无统计学意义。透析3个月后,DU组的体质量和水肿程度有所下降（P < 0.05）,但仍高于LU和NU组（P < 0.05）;腹透液总入量、超滤量、尿量下降速度比LU组和NU组高（P < 0.05）;rKt/V 比腹透前显著下降（P < 0.05）。3组的血清白蛋白和tKt/V差异无统计学意义。 结论 开始腹透患者过度超滤可引起残余肾功能下降。对于有一定残余肾功能的患者要注意避免快速或过多超滤。     

Impact of social factors on patients on peritoneal dialysis.

BACKGROUND: Clinical outcomes among patients on peritoneal dialysis (PD) might not be linked to medical factors alone. We studied the clinical impact of various social factors among patients on PD. METHODS: In a cohort of 102 consecutive patients who started PD in a single centre between 2003 and 2004, we evaluated the effects of social factors on the development of peritonitis and risk of hospitalization after initiation of PD. RESULTS: Of 102 incident PD patients, 35 subjects (34.3%) were referred to nephrologists more than 3 months before dialysis initiation. During 85.7 patient-years of observation (median follow-up, 10.7 months), four subjects died and six underwent kidney transplantation. Patients receiving social security assistance and those younger than 40 years fared worse than others in terms of their risk of peritonitis. Mean peritonitis-free time for subjects who were on social security assistance was 2.7 months, and for those who were not, 16.4 months (P = 0.045). In the Cox proportional hazards analysis, need for social security assistance and illiteracy were the only statistically significant factors associated with the time to a first peritonitis, after adjustment for social characteristics and relevant coexisting medical factors. Dependence on social security assistance prior to PD was associated with a >2-fold increased likelihood of peritonitis, with an adjusted risk ratio of 2.69 (95% confidence interval, 1.10 to 6.54; P = 0.029). The total number of hospitalization days was similar between those who received social security assistance and those who did not: 17.4+/-14.6 days (range, 4-50 days) vs 17.9+/-14.0 days (range, 0-60 days) (P = 0.89). CONCLUSIONS: Our results confirm that socioeconomic status is closely associated with the rate of peritonitis among PD patients. The long-term reliability of these social predictors remains to be validated.     

Impact of primary omentectomy on longevity of peritoneal dialysis catheters in children

Background

The purpose of this study was to determine the impact of omentectomy on peritoneal dialysis catheter failure rates in pediatric patients with renal failure.

Methods

A retrospective review of children undergoing peritoneal catheter placement was performed over a 22-year period. Children were segregated into those undergoing catheter placements with omentectomy or without.

Results

One hundred sixty-three patients were reviewed, with a 1:1.03 ratio of male to female patients. The mean age was 6.25 ± 5.58 years. Fifty-three percent underwent omentectomy. Catheter failure was observed in 63 children (39%). Catheter obstruction was identified in 36%. Peritonitis led to failure in 9.8%. Catheter failure rate was significantly reduced with the performance of omentectomy (23% without omentectomy vs 15% with omentectomy, P = .0054). Differences in time to catheter failure did not reach statistical significance in the omentectomy group (759 vs 280 days, P = .13).

Conclusions

Omentectomy conferred improved utility of peritoneal catheters in children. Omentectomy appears useful in children undergoing peritoneal dialysis catheter placement.     

Guidelines by an ad hoc European committee on adequacy of the paediatric peritoneal dialysis prescription.

AcknowledgmentsNotesReferences