Impact of cardiopulmonary bypass management on postcardiac surgery renal function

OBJECTIVE: Cardiac surgery on cardiopulmonary bypass (CPB) is associated with postoperative renal dysfunction and up to 4% of patients with normal preoperative renal function develop acute renal failure (ARF) requiring dialysis. According to recent investigations, CPB management is not evidence-based and, thus, current clinical CPB practice may favor renal dysfunction. The purpose of our study was to investigate if postcardiac surgery renal dysfunction is influenced by CPB management. METHODS: We selected three groups of patients with normal preoperative renal function who had been subjected to cardiac surgical procedures on CPB: 44 patients with postoperative ARF requiring hemofiltration/dialysis (ARF group), 51 patients with postoperative renal dysfunction not requiring hemofiltration/dialysis (serum creatinine increase > 0.5 mg/dl within 48 h postsurgery: CREA group), and 48 patients with normal postoperative renal function (Control group). The patients' on-line CPB records were analyzed for CPB duration, CPB perfusion pressure, CPB flow, and periods on CPB at a perfusion pressure <60 mmHg. On-CPB diuretic and vasoconstrictor medication was recorded. RESULTS: Patient demographics were similar for the three groups. In the ARF group, CPB duration was longer (166 +/- 77 [standard deviation, SD] min) compared to CREA (115 +/- 41 min; p < 0.001) and to Control groups (107 +/- 40 min; p < 0.001), and mean CPB flow was lower (2.35 +/- 0.36 l/min/m2) compared to CREA (2.61 +/- 0.35 l/min/m2; p = 0.0015) and to Control groups (2.51 +/- 0.33 l/min/m2; p = 0.09). Mean arterial pressure on CPB (ARF: 61 +/- 10; CREA: 60 +/- 7; CONTROL: 63 +/- 9 mmHg; p = 0.19) as well as furosemide and norepinephrine medication on CPB were similar for the groups. Compared to Control (46 +/- 26 min), CPB duration at arterial pressures <60 mmHg was longer in ARF (78 +/- 60 min; p = 0.034) and in CREA (62 +/- 36 min;p = 0.048). CONCLUSIONS: Our data suggest that current clinical CPB management impacts postoperative renal function. We found that patients with normal preoperative renal function who developed postoperative ARF had longer CPB duration, lower CPB perfusion flow, and longer periods on CPB at pressures < 60 mmHg compared to patients with no post CPB ARF. However, our data do not allow us to separate these CPB-related factors from the potential influence of perioperative low cardiac output syndrome as a cause for postoperative ARF. Thus, future clinical studies are required to elucidate CPB-induced ARF and to optimize CPB management for ARF prevention.     

High volume peritoneal dialysis for acute renal failure.

BACKGROUND: Peritoneal dialysis (PD) is still widely used for acute renal failure (ARF) in developing countries despite concerns about its inadequacy. Continuous PD has been evaluated in ARF by analyzing the resolution of metabolic abnormality and normalization of plasma pH, bicarbonate, and potassium. Methodology: A prospective study was performed on 30 ARF patients who were assigned to high-dose continuous PD (Kt/V = 0.65 per session) via a flexible catheter (Tenckhoff) and automated PD with a cycler. Fluid removal, pH and metabolic control, protein loss, and patient outcome were evaluated. RESULTS: Patients received 236 continuous PD sessions; 76% were admitted to ICUs. APACHE II score was 32.2+/-8.65. BUN concentrations stabilized after 3 sessions, creatinine after 4, and bicarbonate and pH after 2. Fluid removal was 2.1+/-0.62 L/day. Creatinine and urea clearances were 15.8+/-4.16 and 17.3+/-5.01 mL/minute respectively. Normalized creatinine clearance and urea Kt/V values were 110.6+/-22.5 L/week/1.73 m(2) body surface area and 3.8+/-0.6 respectively. Solute reduction index was 41%+/-6.5% per session. Serum albumin values remained stable in spite of considerable protein losses (median 21.7 g/day, interquartile range 9.1-29.8 g/day). Regarding ARF outcome, 23% of patients presented renal function recovery, 13% remained on dialysis after 30 days of follow-up, and 57% died. CONCLUSION: High-dose continuous PD by flexible catheter and cycler was an effective treatment for ARF. It provided high solute removal, allowing appropriate metabolic and pH control, and adequate dialysis dose and fluid removal. Continuous PD can therefore be considered an alternative to other forms of renal replacement therapy in ARF.     

腹膜透析治疗小儿先心病术后急性肾功能衰竭

目的 探讨腹膜透析(PD)对小儿先天性心脏病术后急性肾功能衰竭(ARF)的治疗效果。方法 对36例先心病术后ARF行腹膜透析治疗患儿的临床资料进行透析效果、转归合并症进行回顾性分析。结果 单纯ARF的死亡率12.5％,显著低于合并其它系统器官衰竭组的45％(P<0.05),腹膜透析3～30天内肾功能恢复,其中1～2天内血钾[K~ ]恢复正常,2～5天内血碳酸氢根[HCO_3~-]恢复正常,4～6天内血尿素氮(BUN)下降49.2％,血肌酐(Cr)下降42.6％。结论 对小儿先心病术后ARF,及早进行腹膜透析具有较好的治疗效果。     

Factors affecting the use of peritoneal dialysis among the ESRD population in India: a single-center study.

OBJECTIVES: Factors such as limited health-care budget allotment and poor accessibility of the majority of the population to hemodialysis (HD) facilities should favor the use of peritoneal dialysis (PD) in India. However, only 6% of end-stage renal disease patients undergoing dialysis in India are on PD. We undertook this prospective study to evaluate various factors that could contribute to this low rate of use of PD at a tertiary-care state-run hospital in Northern India. METHODS: All the patients who entered our HD or PD program from August 2001 to December 2003 were interviewed using a preset questionnaire. The questionnaire recorded their basic disease and comorbidity, social and demographic characteristics, awareness of the various modalities of renal replacement therapy (RRT), and the reasons for choosing their present modality of therapy. Treating nephrologists were also interviewed with respect to the factors that, in their opinion, were responsible for the limited use of PD at our institute. RESULTS: In total, 342 patients on HD, 66 patients on PD, and 24 nephrologists were interviewed. The rate of PD use was 16.2%. Mean age of patients on HD and PD was 34.6 +/- 11.8 years and 62.9 +/- 10.3 years respectively (p < 0.0001). The incidence of diabetes mellitus and coronary artery disease in the HD and PD populations was 2.5% and 62.5%, and 9.1% and 46.7% respectively (p < 0.0001 for both). Only 30.4% of patients on HD were aware of PD as a modality of RRT and 83.6% of them found PD to be expensive, 65.4% had low enthusiasm toward a domiciliary therapy such as PD, and 61.5% were not recommended PD by their nephrologist. Only 5 (7.6%) patients were initiated on PD directly, the remaining 61 patients were shifted from HD after a mean duration on HD of 185.3 +/- 15.4 days: 67.1% were shifted due to poor tolerance of HD, 29.4% were advised to shift to PD because of comorbidity and vascular access problems, and only 3.3% took up PD because of the independent lifestyle it offered. None of the interviewed nephrologists routinely discussed PD in predialysis counseling. They found financial constraints (100%), lack of patient enthusiasm (100%), doubtful patient compliance (83.2%), and lack of an organized PD program (79.2%) to be the main factors limiting more widespread use of PD at our institute. CONCLUSIONS: Peritoneal dialysis is an underused modality of RRT at our institute. The patients who are taken up for PD at our institute are elderly and have a higher incidence of other comorbid conditions, such as diabetes mellitus and coronary artery disease. Also, most patients who switch to PD do so due to their unsuitability for HD rather than by their own choice. The factors contributing to this low rate of use of PD are ignorance of PD, increased cost of therapy, low enthusiasm toward domiciliary therapy, and lack of adequate infrastructure for PD at our institute. Effective predialysis counseling, reduction in the cost of the therapy, and development of an adequate infrastructure can increase the rate of use of PD.     

Acute renal failure in critically ill patients: prognosis for recovery of kidney function after prolonged dialysis support

OBJECTIVE: To clarify the prognosis for eventual recovery of kidney function in patients who experience prolonged dialysis dependence after acute renal failure (ARF). DESIGN: Retrospective, chart review. SETTING: Inpatients of a large, referral-based hospital. PATIENTS: Twenty-six consecutive survivors of ARF who required greater than 4 wk of dialysis support. RESULTS: All 26 patients were critically ill and developed ARF during treatment in an ICU. The clinical course of these patients was characterized by multiple episodes of renal ischemia or nephrotoxin exposure during dialysis dependence. However, despite multiple renal insults and prolonged dialysis support (mean duration 8.4 +/- 0.7 wk), 23 (88%) of the 26 patients recovered sufficient kidney function to discontinue dialysis. Preexisting renal impairment was associated with a greater risk of irreversible renal failure, and, in patients able to discontinue dialysis, renal recovery was often incomplete. CONCLUSIONS: Despite some renal damage, most critically ill patients who survive ARF requiring prolonged dialysis support recover life-sustaining kidney function.     

High incidence of renal failure requiring short-term dialysis: a prospective observational study

BACKGROUND: Previous estimates of incidence of acute renal failure (ARF) requiring renal replacement therapy have varied from 18 to 75 patients per million per year, but have been beset by problems of definition. AIM: To investigate whether the '90-day rule' provides a more reliable, reproducible and robust estimate of the need for short-term dialysis. SETTING: District general hospital serving a population of 147 000. DESIGN: Prospective observational study. METHODS: Patients who received renal replacement therapy in Dumfries and Galloway between 01/01/94 and 31/12/2000 were divided into two groups: long-term dialysis (> or =90 days) and short-term dialysis (<90 days). RESULTS: Of 302 patients, 193 received short-term dialysis, giving an incidence for short-term dialysis of 187 patient episodes per million per year (95%CI 170-203). Use of a more conventional definition for ARF (including all ARF and acute-on-chronic renal failure, but excluding patients with chronic renal failure who present acutely) produced a similar estimate at 176 patients per million per year (95%CI 160-193). DISCUSSION: The 90-day rule estimated the incidence of short-term dialysis/ARF at nearly twice the incidence of chronic renal failure requiring dialysis, and more than twice the most recent estimate of the incidence of ARF in the UK. The main attraction of the 90-day rule is its simplicity. If the high level of short-term dialysis/ARF found in our study is confirmed by other centres, there are significant resource implications for the provision of renal care.     

Preoperative 24-hour urine amount as an independent predictor of renal outcome in poor cardiac function patients after coronary artery bypass grafting

PURPOSE: To investigate the incidence and the main pre-operative risk factors for the development of acute renal failure (ARF) in triple vessels coronary artery bypass grafting (CABG) with special reference to a subset of patients with poor cardiac function (ejection fraction <50%). PATIENTS: The study included the patients (n = 66) requiring CABG from January 1, 1995 to January 1, 2002 in a medical center. RESULTS: A high percentage (84.8%) of patients developed ARF and 57.6% of patients received hemodialysis (HD). Preoperative variables significantly associated with the development of ARF included increased age, increased preoperative serum creatinine, decreased preoperative 24-hour urine output and accepted emergent CABG. By the logistic multivariate regression model, increased age (OR = 1.16), preoperative serum creatinine (OR = 3.58,), decreased preoperative 24-hour urine amount (OR = 0.99,) and emergent CABG (OR = 2.01) were independently associated with ARF. As for the need for HD, those factors including, preoperative serum creatinine (2.11 +/- 1.13 v 3.08 +/- 1.67 mg/dL) and preoperative 24-hour urine output (1358.6 +/- 745.9 v 755.2 +/- 572.1 mL/day) were significantly associated with requirement of dialysis. Using multivariate logistic regression, the significant risk factors independently associated with dialysis were preoperative serum creatinine (OR = 1.34) and preoperative 24-hour urine output (OR = 0.99). Patients with non- oliguric renal failure had significantly greater chance of recovering their renal function after cardiac surgery compared to those with oliguria (36.9% v 10.0%, P <.05). CONCLUSION: Preoperative 24-hour urine amount and pre-operative serum creatinine can provide valuable information for predicting the likelihood of developing acute renal failure and requiring dialysis in this subgroup of patients.     

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.     

Impact of first dialysis modality on outcome of patients contraindicated for kidney transplant.

BACKGROUND: We compared, in patients contraindicated for kidney transplant, outcomes between those patients who were only on hemodialysis (HD) and those who were given peritoneal dialysis (PD) as first renal replacement therapy (RRT). DESIGN: Prospective, population-based cohort study of incident cases of end-stage renal disease between June 1997 and June 1999. SETTING: A network of dialysis care: NEPHROLOR, that is, all the renal units in Lorraine, one of the 22 French administrative regions (population over 2.3 million people). PARTICIPANTS: 387 patients were contraindicated for kidney transplant during the first 2 years of RRT: 284 were on HD, 103 on PD. Mean age was 67.6 +/- 11.3 years for HD patients and 70.8 +/- 11.4 years for PD patients (p = 0.015). MAIN OUTCOME MEASURES: Mortality until June 2003, hospitalization over the 2 first years of RRT, and Kidney Disease and Quality of Life Short Form (KDQOL-SF) 6 and 12 months after initiation of RRT. RESULTS: HD patients were more likely to die from cardiac or cerebrovascular causes, PD from cachexia or withdrawal from dialysis. Whatever mode of RRT, the unadjusted 2-year and 5-year survival rates were similar (p = 0.98). The rate of total duration of hospital stay per month of RRT was similarin HD and PD groups: 2.7 +/- 4.5 and 2.9 +/- 4.2 days respectively (p = 0.7). PD was associated with better quality of life than HD. The dimensions Role limitation due to emotional function, Burden of kidney disease, and Role limitation due to physical function ranked first, second, and third for PD. CONCLUSION: In Lorraine, end-stage renal disease patients who were given PD as first-line RRT had no excess of death risk or hospitalizations, and better quality of life the first year of RRT.     

Survivors of acute renal failure who do not recover renal function

Overall survival in 1095 with severe acute renal failure (ARF) between 1984 and 1995 was 59.5%. Of these, 107 (16.2%) remained dependent on long-term dialysis. The frequency of end-stage renal failure (ESRF) in survivors of ARF varied between 3% and 41% according to the cause of ARF, being highest in those with acute renal parenchymal disease (in whom survival was also among the highest at 84%) and lowest in ARF due to obstetrics and trauma. Patients failing to regain adequate renal function did not appear to differ on clinical grounds from survivors who became dialysis-independent. Survival in those requiring long-term dialysis was less good than for other patients with ESRF, partly due to excess mortality in those for whom vascular disease or surgery was the precipitating cause of ARF. Six patients recovered sufficient renal function to become independent of dialysis after 3-18 months on regular dialysis therapy (6-21 months after onset of ARF). ESRF resulting from ARF is more frequent than previously reported. This increase may be due to a changing case-mix, increasing age of patients (and hence reduced capacity for renal recovery), and an increase in aggressive surgery for patients with advanced vascular disease. This presents a significant and increasing problem, with implications for both clinical management and the provision of dialysis services.      

Outcome of Acute Kidney Injury in Sudanese Children — An Experience from a Sub-Saharan African Unit

♦ Background: Acute Kidney Injury (AKI) is an important cause of morbidity and mortality in developing countries. Although continuous renal replacement therapy is gaining more popularity worldwide, peritoneal dialysis (PD) in children remains an appropriate therapy for AKI in children for all age groups including neonates.♦ Methodology: We retrospectively reviewed all children who have been admitted with AKI at the pediatric nephrology unit, Soba University Hospital, Khartoum, during the period from January 2005 to December 2011.♦ Results: Over 7 years we recorded 659 children of whom 362 (54.9%) were male. The spectrum of age was variable with the majority being neonates, 178 (27.1%). The average patient admission rate was 94 patients per year, with an estimated incidence of 9.8 patients/million population/year. Common causes of AKI were sepsis 202 (30.8%), acute glomerulonephritis 75 (11.5%) and obstructive uropathy due to stones 56 (8.5%). The most common dialysis modality used was PD, 343 (52.4%), and peritonitis was reported in 53 (15.4%) patients. Recovery from AKI was achieved in 450 (68.9%) children, 37 (5.7%) went into chronic kidney disease (CKD), 33 (5.1%) referred to the pediatric surgery and 194 (29.7%) died.♦ Conclusion: In the setting of developing countries where AKI is a common cause of morbidity and mortality, reasonably equipped renal units with adequately trained medical staff may save many lives. International funding programs for communicable diseases and charity organizations should include AKI management in their programs. Acute PD remains the treatment modality of choice for AKI in developing countries.     

Bimodal dialysis: an integrated approach to renal replacement therapy.

BACKGROUND: Peritoneal dialysis (PD) and hemodialysis (HD) are both widely used as sole therapies for end-stage renal disease (ESRD). There is still controversy over which (if either) is superior in terms of patient outcomes. Peritoneal dialysis offers the advantages of long, slow, continuous ultrafiltration and potentially enhanced protection of residual renal function (RRF). In contrast, HD offers superior solute removal at the cost of undesirable cardiovascular tolerance of high rates of sodium and water removal. The aim of this study was to investigate the clinical feasibility of offering a combined treatment of both modalities [bimodal dialysis (BMD)] to incident patients reaching ESRD. We set out to investigate if it might be possible to utilize the intrinsic advantages of both modalities within a setting of good patient acceptability. METHODS: We prospectively studied 8 patients. They were recruited in the pre-ESRD phase from a specialist low clearance clinic. An arteriovenous fistula was formed and peritoneal catheters were inserted. The BMD consisted of 2, 3-hour, high efficiency, euvolemic HD sessions per week in combination with 2 PD exchanges per day to provide a degree of solute clearance and all of the ultrafiltration. Adequacy was measured independently for each modality. Patients were followed using the standard range of evaluations in addition to RRF (by creatinine clearance and EDTA clearance), echocardiography (left ventricular mass and ventricular performance), treatment outcomes, patient symptoms, and complications. RESULTS: Mean time on BMD was 346 +/- 74.9 (range 245 - 431) days. Peritonitis rate was 21 months per episode (mean 0.6 +/- 0.9, 0 - 2 episodes per patient). Mean peritoneal ultrafiltration volume was 1.58 +/- 0.32 (1.3 - 2.1) L per day. Delivered Kt/V and weekly PD Kt/V did not change significantly. Patients' RRF was maintained over the study period, as were serum albumin and control of serum phosphorus. Blood pressure was controlled with a reduction in the number of antihypertensive agents. Left ventricular mass index reduced over the treatment period, from a mean of 194 +/- 31.2 (161 - 265) to 156 +/- 21.2 (138 - 189) g/m2 (p = 0.05). Ventricular performance remained unchanged over the study [ejection fraction 50.4 +/- 11.1 (38 - 67) % to 48 +/- 8.0 (48 - 67) %]. Mean time during BMD spent on HD alone was 4.2 +/- 6.9 (0 - 16) days, and on PD alone 9.2 +/- 10.6 (0 - 25) days. CONCLUSION: This study suggests that BMD is a feasible treatment for ESRD. It is associated with adequate solute removal and good hemodynamic/volume control, and allows increased treatment flexibility for coping with complications normally requiring recourse to unplanned HD with temporary central venous access.     

Serum albumin and other serum protein fractions in stable patients on peritoneal dialysis.

BACKGROUND: Hypoalbuminemia is common in peritoneal dialysis (PD) patients; but the reduction in serum albumin levels (SAlb) that should be expected in stable PD patients is less clear. OBJECTIVES: To determine prospectively, in a group of stable PD patients without comorbid conditions, the changes in SAlb concentration and in the concentrations of the other serum protein fractions. To investigate the best determinants of a significant decrease in SAlb levels. DESIGN: Prospective observational study. METHODS: Seventeen PD patients in stable clinical condition, with no signs of systemic inflammatory response, were included in the study. SAlb and the electrophoretic pattern of serum proteins were determined immediately before PD start, and after 6, 9, 12, 15, 18, 21, and 24 months on PD. In each study period, clinical characteristics, adequacy parameters, protein catabolic rate (PNPNA: protein equivalent of non protein nitrogen appearance), and protein losses were determined. Patients were divided into two subgroups according to whether SAlb decreased less than 10%, or 10% or more, from baseline values after 24 months on PD. The main differences between the subgroups were investigated. RESULTS: Mean SAlb did not decrease significantly after 24 months on PD (from baseline 3.99 +/- 0.46 g/dL to 3.80 +/- 0.54 g/dL), though percentage SAlb values did (58.36% +/- 5.58% vs 55.15% +/- 5.42%, p < 0.01). A weak increase in alpha2-globulin was observed after 18 months on PD (from 10.62% +/- 2.53% to 12.96% +/- 2.51%, p = 0.001). Alpha-globulin showed a sustained increase from a mean baseline value of 3.51% +/- 1.09% to 6.83% +/- 2.13% after 24 months (p < 0.0001). Seven patients had a reduction in SAlb greater than 10% after 24 months on PD. Kt/V urea and residual renal function tended to be lower in patients whose SAlb decreased. Mean PNPNA was significantly lower in patients who had a reduction in SAlb (0.76 +/- 0.12 g/kg/day vs 0.96 +/- 0.12 g/kg/day, p < 0.0001). However, total protein loss was even greater in patients who had no SAlb reduction. CONCLUSIONS: After 24 months on PD, a mean reduction in SAlb of 10%-15% from baseline values should be expected only in those stable patients whose PNPNA is low.     

Exercise capacity in pediatric patients with end-stage renal disease.

OBJECTIVE: To evaluate the correlation between exercise capacity and hemoglobin in pediatric patients with end-stage renal disease (ESRD) treated with automated peritoneal dialysis (APD) and hemodialysis. DESIGN: Prospective case-control study and retrospective review. SETTING: Dialysis summer camp and Children's Mercy Hospital exercise laboratory. PARTICIPANTS: Prospective evaluation conducted with 14 patients (9 males, mean age 14.5 +/- 2.5 years) who received either home APD (5 patients) or in-center hemodialysis (9 patients), and 8 healthy age-matched controls. Retrospective data derived from 10 children (7 males, mean age 12.3 +/- 3.3 years), all of whom received APD. INTERVENTION: Maximal treadmill evaluation conducted with each patient and control. The hemoglobin value of each patient was also assessed. MAIN OUTCOME MEASURES: Comparison of the following data generated during treadmill protocol: peak heart rate, blood pressure, oxygen saturation, treadmill time, oxygen consumption (VO2), ventilation (Ve), oxygen consumption at anaerobic threshold (VO2AT), and respiratory exchange ratio. RESULTS: The hemoglobin value of the current patient group (12.8 +/- 1.6 g/dL) was significantly greater than the previously studied patients (10.5 +/- 1.1 g/dL) (p = 0.001). Treadmill time, VO2, and VO2AT were significantly lower in both groups of dialysis patients compared to the control subjects (p < 0.05). No differences were noted in any of these variables when comparing these two groups of dialysis patients only. CONCLUSION: The exercise capacity of pediatric dialysis patients is significantly poorer than that of healthy children, an outcome apparently related to factors other than normalization of the hemoglobin value.     

Metallothionein and dendritic cells in skin of end-stage renal disease patients not on dialysis, or on hemodialysis or peritoneal dialysis.

OBJECTIVE: Renal failure leads to a variety of defects in immune function. The skin, as a major player in the immune system network, also exhibits multiple derangements. The pathogenesis of these defects and derangements are poorly understood; therefore, we studied immune competent cells, dermal dendrocytes (DC), and a special proinflammatory protein, metallothionein (MT), in the skin of these patients. DESIGN: 22 patients with end-stage renal disease (ESRD) but not on dialysis, 18 patients on hemodialysis (HD), 14 patients on peritoneal dialysis (PD), and 35 healthy controls were included in the study. Immunohistochemical staining of skin biopsies for DC and MT was performed with the following antibodies: for DC, antibody against factor XIIIa; and for MT, Dako-MT, E9 (Dako, Carpinteria, California, USA). Measurements were made by counting stained DC per square millimeter, and by optical density (OD) for MT (mean SEM). RESULTS: Metallothionein was increased in the skin of HD (OD 0.42 +/- 0.05, p < 0.01) and PD patients (OD 0.33 +/- 0.04, p < 0.05) compared to controls (OD 0.23 +/- 0.02) and ESRD patients not on dialysis (OD 0.22 +/- 0.05). In contrast, numbers of DC were reduced in patients on PD compared to controls (59 +/- 13 vs 96 +/- 59 DC/mm2, p < 0.01) and increased in patients with ESRD prior to dialysis (141 +/- 13 DC/mm2, p < 0.05). Patients on HD were in-between (105 +/- 20 DC/mm2), with a significant difference versus patients on PD (p < 0.05). CONCLUSIONS: Our data show that the mode of dialysis influences the number of antigen-presenting cells in the dermis. However, in both dialysis modes, a proinflammatory immune status of the skin (MT) was present and, therefore, other regulatory elements for dermal dendrocytes apart from proinflammation exist.     

Update on dialytic management of acute renal failure

The potential impact of renal replacement therapy on clinical outcomes in acute renal failure (ARF) remains a subject of ongoing investigation and controversy. This article reviews in depth the clinical trials to date that have examined the effect of dialysis-related variables on outcomes of patients with hospital-acquired ARF. In particular, the role of the dialysis modality, dialyzer characteristics, and dosing strategies are discussed. Clinical trials comparing intermittent hemodialysis (HD) to continuous renal replacement therapies (CRRT) have failed to demonstrate a survival difference when adjusting for disease severity. Similarly, studies evaluating dialyzer membrane biocompatibility and flux properties had no impact on survival. Efforts aimed at measuring dialysis adequacy in patients with ARF receiving HD using urea kinetic modeling are hindered by a lack of understanding of solute kinetics in this setting. However, dosing strategies during CRRT are promising. Finally, the application of cell therapy to the successful substitution of renal function shows promise for the future.     

SEN virus infection in patients on peritoneal dialysis.

BACKGROUND: Many reports have demonstrated SEN virus (SEN-V) infection rates in hemodialysis patients, but the SEN-V infection rate in peritoneal dialysis (PD) patients has never been reported. In this study, we determined the prevalence rate of SEN-V viremia in a PD population. METHODS: Serum samples from 47 PD patients and a control group of 43 subjects from the general population at their health examination were assayed for SEN-V-D and -H viremia using polymerase chain reaction. RESULTS: The proportions of female gender (p = 0.001), previous transfusion (p < 0.0001), and higher mean serum AST level (p = 0.012) were significantly higher in PD patients. The prevalence rates of SEN-V-D and/or -H viremia were not significantly different between PD patients and controls (27.7% vs 32.6%). SEN-V-D(+) patients had lower mean duration of PD than SEN-V(-) patients. Mean ALT level was significantly lower in SEN-V-H(+) than in SEN-V(-) patients (12.8 +/- 5.8 vs 19.6 +/- 12.1 (IU/L), p = 0.025). None of the SEN-V-infected PD patients had overt clinical or biochemical signs of liver disease. There were no statistically significant differences in prevalence of SEN-V-D and/or -H viremia between automated PD (APD) patients and continuous ambulatory PD (CAPD) patients. CONCLUSIONS: These results indicate that the SEN-V infection rate is not different between healthy individuals and PD patients. Infection with SEN-V is not associated with evident liver disease in PD patients and SEN-V infection rate is not different between APD patients and CAPD patients.