The role of residual renal function on potassium intake and excretion in patients on peritoneal dialysis.

BACKGROUND: Patients on chronic dialysis are at increased risk of developing disorders in potassium balance. The preservation of residual renal function (RRF), frequently observed in patients on peritoneal dialysis (PD), may contribute to better control of serum potassium. This study aimed to investigate the role residual renal function on potassium intake and excretion in PD patients. METHODS: In this cross-sectional study, dietary potassium was evaluated by the 3-day food record. Potassium concentration was determined in serum, 24 h dialysate, stool ample, and 24 h urine of patients with diuresis > 200 mL/day, who were considered non-anuric. RESULTS: Fifty-two patients, 50% men, 52.6 ± 14.0 years, and PD vintage 19.5 [7.0-44.2] months, were enrolled. Compared to the anuric group (n = 17, 33%), the non-anuric group (n = 35, 67%) had lower dialysate potassium excretion (24.8 ± 5.3 vs 30.9 ± 5.9 mEq/d; p = 0.001), higher total potassium intake (44.5 ± 16.7 vs 35.1 ± 8.1 mEq/d; p = 0.009) and potassium intake from fruit (6.2 [2.4-14.7] vs 2.9 [0.0-6.0]mEq/d; p = 0.018), and no difference in serum potassium (4.8 ± 0.6 vs 4.8 ± 0.9 mEq/L; p = 0.799) and fecal potassium (2.2 ± 0.5 vs 2.1 ± 0.7 mEq/L; p = 0.712). In non-anuric patients, potassium intake correlated directly with urinary potassium (r = 0.40; p = 0.017), but not with serum, dialysate, or fecal potassium. In the anuric group, potassium intake tended to correlate positively with serum potassium (r = 0.48; p = 0.051) and there was no correlation with dialysate or fecal potassium. CONCLUSION: The presence of residual renal function constitutes an important factor in the excretion of potassium, which may allow the adoption of a less-restrictive diet.

The benefits of peritoneal dialysis (PD) solution with low-glucose degradation product in residual renal function and dialysis adequacy in PD patients: A meta-analysis / Beneficios de la solución de diálisis peritoneal (DP), con producto de degradación bajo en glucosa, en la función renal residual y la adecuación de la diálisis en pacientes en DP: un metanálisis

Abstract The peritoneal effects of low-glucose degradation product (GDP)-containing peritoneal dialysis (PD) solutions have been extensively described. To systematically evaluate the efficacy and safety of low GDP solution for PD patients, specifically the effect on residual renal function (RRF) and dialysis adequacy, we conducted a meta-analysis of the published randomized controlled trials (RCTs). Different databases were searched for RCTs that compared low GDP-PD solutions with conventional PD solutions in the treatment of PD patients with continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD). The outcomes of RCTs should include RRF and may include small solute clearance, peritoneal transport status, nutritional status, and all-cause mortality. Seven studies (632 patients) were included. Compared with the conventional solution, low-GDP solution preserved RRF in PD patients over time (MD 0.66 mL/min, 95% CI 0.34 to 0.99; p<0.0001), particularly in one year of treatment (p<0.01), and improved weekly Kt/V (MD 0.11, 95% CI 0.05 to 0.17; p=0.0007) without an increased 4-hour D/Pcr (MD 0.00, 95% CI -0.02 to 0.02; p=1.00). Notably, the MD of RRF and urine volume between the two groups tended to decrease as time on PD progressed up to 24 months. Patients using low GDP PD solutions did not have an increased risk of all-cause mortality (MD 0.97, 95% CI 0.50 to 1.88; p=0.93). Our meta-analysis confirms that the low GDP PD solution preserves RRF, improves the dialysis adequacy without increasing the peritoneal solute transport rate and all-cause mortality. Further trials are needed to determine whether this beneficial effect can affect long-term clinical outcomes.

Resumen Los efectos peritoneales de las soluciones de diálisis peritoneal (DP) que contienen productos de degradación bajos en glucosa (PIB) se han descrito ampliamente. Para evaluar sistemáticamente la eficacia y la seguridad de la solución de PIB bajo para pacientes en DP, específicamente el efecto sobre la función renal residual (RRF) y la adecuación de la diálisis, realizamos un metanálisis de los ensayos controlados aleatorios (ECA) publicados. Se realizaron búsquedas en diferentes bases de datos de ECA que compararan la solución de DP de bajo PIB con la solución de DP convencional en el tratamiento de pacientes con EP con CAPD y APD. Los resultados de los ECA deben incluir la RRF y pueden incluir la depuración de solutos pequeños, el estado nutricional, el estado del transporte peritoneal y la mortalidad por todas las causas. Se incluyeron siete estudios (632 pacientes). En comparación con la solución convencional, la solución de bajo PIB preservó la FRR en pacientes con EP a lo largo del tiempo (DM 0,66 mL/min, IC del 95%: 0,34 a 0,99; p<0,0001), particularmente en un año de tratamiento (p<0,01), y mejoró el Kt/V semanal (DM 0,11, IC del 95%: 0,05 a 0,17; p = 0,0007), sin un aumento de D/Pcr a las 4 horas (DM 0,00, IC del 95%: -0,02 a 0,02; p = 1,00). Los pacientes que usaron una solución para DP con bajo contenido de GDP no tuvieron un mayor riesgo de mortalidad por todas las causas (DM 0,97; IC del 95%: 0,50 a 1,88; p = 0,93). Nuestro metanálisis confirma que la solución de DP de bajo PIB preserva la FRR, mejora la adecuación de la diálisis sin aumentar la tasa de transporte peritoneal de solutos y la mortalidad por todas las causas. Se necesitan más ensayos para determinar si este efecto beneficioso puede afectar los resultados clínicos a largo plazo.

KDOQI US Commentary on the 2020 ISPD Practice Recommendations for Prescribing High-Quality Goal-Directed Peritoneal Dialysis.

The recently published 2020 International Society for Peritoneal Dialysis (ISPD) practice recommendations regarding prescription of high-quality goal-directed peritoneal dialysis differ fundamentally from previous guidelines that focused on "adequacy" of dialysis. The new ISPD publication emphasizes the need for a person-centered approach with shared decision making between the individual performing peritoneal dialysis and the clinical care team while taking a broader view of the various issues faced by that individual. Cognizant of the lack of strong evidence for the recommendations made, they are labeled as "practice points" rather than being graded numerically. This commentary presents the views of a work group convened by the National Kidney Foundation's Kidney Disease Outcomes Quality Initiative (KDOQI) to assess these recommendations and assist clinical providers in the United States in interpreting and implementing them. This will require changes to the current clinical paradigm, including greater resource allocation to allow for enhanced services that provide a more holistic and person-centered assessment of the quality of dialysis delivered.

Hemodiálisis incremental. ¿Una propuesta terapéutica? / Incremental hemodialysis. A therapeutic proposal?

La función renal (FR) es medida por varios métodos. La más utilizada es el aclaramiento de creatinina (ClCr), que reflejaría, el filtrado glomerular (FG). Para su medición se recurre a la recolección de orina durante 24 horas o a la utilización de fórmulas, siendo la más utilizada, la ecuación CKD-EPI (Chronic kidney disease Epidemiology Collaboration). La disfunción renal se clasifica en 5 estadios. El estadio 5 (cuando el ClCr es igual o inferior a 15 ml/min), es cuando los pacientes están prontos a recibir tratamiento sustitutivo renal (TSR). La hemodiálisis (HD), es una técnica muy utilizada como TSR y normalmente es llevada a cabo 3 veces a la semana, por 4 horas cada una. Un paciente de 59 años, quién debido a la distancia entre su domicilio y el Centro de diálisis decide (consentimiento firmado), someterse a solo 2 sesiones de HD por semana. Al inicio del tratamiento, el paciente presentaba todos los datos clínicos y bioquímicos de la Enfermedad renal Crónica Avanzada, estadio 5 y un volumen diurético (VD) ≥ 1 litro/día. En caso de empeoramiento clínico y/o bioquímico, las sesiones de HD serían 3 veces por semana. Al año, los parámetros clínicos, bioquímicos y la función renal residual (FRR), permanecen óptimos. Si FRR (medido por el aclaramiento de urea (Kru) y el VD), declina serán necesarias 3 sesiones de HD, semanales. El mantenimiento de la FRR, está relacionado con la mortalidad y la HD incremental, al preservar mejor la FRR, mejora la sobrevida del paciente.

Several methods are useful to measure renal function (RF). In clinical practice, the creatinina cleareance (CrCl), is widely used, which approximately reflects the glomerular filtration rate (GFR). The 24 hs urine volume collection is required to measure CrCl, however, thanks different formulas we can have a precise CrCl value. The CKD-EPI (chronic kidney disease epidemiology collaboration), is the equation frequently used. According to glomerular filtration rate (GFR), the renal function has been classified in 5 stages. At advances stages (stage 5), (CrCl: 15 ml/min), the patient is faced to receive renal replacement therapy (RRT). Hemodialysis (HD) method is often used. It is carry out 3 times per week (4 hours each). A 59 years old male, due to the distance between the Capital City and his home, decided to receive HD only two times per week (signed consent). At the beginning of the treatment the patient presents all the clinical and biochemical data corresponding to Chronic Renal Failure stage 5. His diuretic volume (DV), ≥ 1 lt/day. In the case of RF deterioration reflected clinical and/or biochemically, the HD session would be 3 times a week. At year, presents adequate residual renal function (RRF) and clinics, biochemical parameters as well. If the RRF (measured by urea clareance (Kru) and the DV) decline, 3 sessions per week will be necessary. The RRF maintenance is related to mortality, therefore, its preservation thanks incremental HD, improve the patient survival.