Daily Peritoneal Ultrafiltration in Anuric Peritoneal Dialysis Patients
Daily Peritoneal Ultrafiltration in Anuric Peritoneal Dialysis Patients
Background. Maintenance dialysis therapy is the only way to remove excess fluid in patients with anuric end-stage renal disease. The optimal ultrafiltration (UF) volume in patients on peritoneal dialysis (PD) remains controversial.
Methods. We retrospectively analysed a cohort of 86 prevalent anuric PD patients followed up for a median of 25.3 months (range, 6 to 54 months). Clinical and PD parameters were recorded yearly. Kaplan–Meier analysis and Cox proportional hazards models were used to identify risk factors of mortality and technique failure in patients with a UF ≥1 L/24 h or <1 L/24 h.
Results. When compared to those with a UF <1 L/24 h, patients with a UF ≥1 L/24 h had significantly higher haemoglobin levels (101.9 ± 20.5 vs 89.3 ± 20.2 g/L, P < 0.05) and tended to be younger (55.0 ± 12.5 vs 60.6 ± 16.1 years, P = 0.10). Also, while Kt/V and CCr were stable over time, UF decreased significantly over the study period (baseline, 1205.5 ± 327.3 ml/24 h vs after 3 years, 870.6 ± 439.8 ml/24 h; P < 0.001). Using Kaplan–Meier analysis, patients with baseline UF <1 L/24 h had significantly worse outcome (survival, 27.2 ± 3.9 vs 42.4 ± 1.9 months; P < 0.001). In multivariate Cox regression analysis, age, time-dependent UF volume and serum albumin were independent predictors of mortality, while UF independently predicted technique failure.
Conclusions. The present study demonstrates a strong predictive value of daily peritoneal UF for both technique and patient survival in prevalent anuric PD patients. Identifying markers of satisfactory fluid status, as well as optimizing therapy to meet UF goals, remains an important clinical target.
Over the past four decades, peritoneal dialysis (PD) has been an important form of renal replacement therapy for patients with end-stage renal disease (ESRD). Previous studies have reported similar patient survival rates for PD and haemodialysis when appropriate adjustments are made for differences in case mix. However, a number of studies have shown that fluid overload is prevalent in PD patients, especially in patients who have lost their residual renal function (RRF). Inadequate fluid removal in this population contributes to hypertension and is associated with an increased risk of cardiovascular disease, hypoalbuminaemia and systemic inflammation. Indeed, reanalysis of the large CANUSA study has shown that the decrease in RRF, rather than peritoneal creatinine clearance, best predicts both mortality and morbidity in PD patients. According to this analysis, every increase of 250 ml in urine output leads to a 36% decrease in mortality risk, again suggesting the important role of fluid status in predicting clinical outcome.
Ultrafiltration (UF) over the peritoneal membrane during dialysis is the standard therapy for removing excess fluid in anuric patients on PD, but the optimal UF volume in this population remains controversial. The European Best Practice Guideline Working Group on Peritoneal Dialysis set an arbitrary target that the minimum net UF in anuric PD patients should be 1 L/day. However, the International Society for Peritoneal Dialysis believes that no numerical target for UF can be formulated using the present data.
In the present study, we performed a retrospective cohort study of prevalent anuric PD patients in our centre. We aimed to study the impact of attaining peritoneal UF targets on clinical outcome in anuric Chinese patients.
Abstract and Introduction
Abstract
Background. Maintenance dialysis therapy is the only way to remove excess fluid in patients with anuric end-stage renal disease. The optimal ultrafiltration (UF) volume in patients on peritoneal dialysis (PD) remains controversial.
Methods. We retrospectively analysed a cohort of 86 prevalent anuric PD patients followed up for a median of 25.3 months (range, 6 to 54 months). Clinical and PD parameters were recorded yearly. Kaplan–Meier analysis and Cox proportional hazards models were used to identify risk factors of mortality and technique failure in patients with a UF ≥1 L/24 h or <1 L/24 h.
Results. When compared to those with a UF <1 L/24 h, patients with a UF ≥1 L/24 h had significantly higher haemoglobin levels (101.9 ± 20.5 vs 89.3 ± 20.2 g/L, P < 0.05) and tended to be younger (55.0 ± 12.5 vs 60.6 ± 16.1 years, P = 0.10). Also, while Kt/V and CCr were stable over time, UF decreased significantly over the study period (baseline, 1205.5 ± 327.3 ml/24 h vs after 3 years, 870.6 ± 439.8 ml/24 h; P < 0.001). Using Kaplan–Meier analysis, patients with baseline UF <1 L/24 h had significantly worse outcome (survival, 27.2 ± 3.9 vs 42.4 ± 1.9 months; P < 0.001). In multivariate Cox regression analysis, age, time-dependent UF volume and serum albumin were independent predictors of mortality, while UF independently predicted technique failure.
Conclusions. The present study demonstrates a strong predictive value of daily peritoneal UF for both technique and patient survival in prevalent anuric PD patients. Identifying markers of satisfactory fluid status, as well as optimizing therapy to meet UF goals, remains an important clinical target.
Introduction
Over the past four decades, peritoneal dialysis (PD) has been an important form of renal replacement therapy for patients with end-stage renal disease (ESRD). Previous studies have reported similar patient survival rates for PD and haemodialysis when appropriate adjustments are made for differences in case mix. However, a number of studies have shown that fluid overload is prevalent in PD patients, especially in patients who have lost their residual renal function (RRF). Inadequate fluid removal in this population contributes to hypertension and is associated with an increased risk of cardiovascular disease, hypoalbuminaemia and systemic inflammation. Indeed, reanalysis of the large CANUSA study has shown that the decrease in RRF, rather than peritoneal creatinine clearance, best predicts both mortality and morbidity in PD patients. According to this analysis, every increase of 250 ml in urine output leads to a 36% decrease in mortality risk, again suggesting the important role of fluid status in predicting clinical outcome.
Ultrafiltration (UF) over the peritoneal membrane during dialysis is the standard therapy for removing excess fluid in anuric patients on PD, but the optimal UF volume in this population remains controversial. The European Best Practice Guideline Working Group on Peritoneal Dialysis set an arbitrary target that the minimum net UF in anuric PD patients should be 1 L/day. However, the International Society for Peritoneal Dialysis believes that no numerical target for UF can be formulated using the present data.
In the present study, we performed a retrospective cohort study of prevalent anuric PD patients in our centre. We aimed to study the impact of attaining peritoneal UF targets on clinical outcome in anuric Chinese patients.
