Peritoneal Dialysis

SUMMARY Peritoneal dialysis (PD) is a renal replacement therapy based on infusing a sterile solution into the peritoneal cavity through a catheter and provides for the removal of solutes and water using the peritoneal membrane as the exchange surface. This solution, which is in close contact with the capillaries in the peritoneum, allows diffusion solute transport and osmotic ultrafiltration water loss since it is hyperosmolar to plasma due to the addition of osmotic agents (most commonly glucose). Infusion and drainage of the solution into the peritoneal cavity can be performed in two ways: manually (continuous ambulatory PD), in which the patient usually goes through four solution changes throughout the day, or machine-assisted PD (automated PD), in which dialysis is performed with the aid of a cycling machine that allows changes to be made overnight while the patient is sleeping. Prescription and follow-up of PD involve characterizing the type of peritoneal transport and assessing the offered dialysis dose (solute clearance) as well as diagnosing and treating possible method-related complications (infectious and non-infectious).

RESUMO A diálise peritoneal (DP) é uma terapia renal substitutiva baseada na infusão de uma solução estéril na cavidade peritoneal através de um cateter, proporcionando a remoção de solutos e água usando a membrana peritoneal como superfície de troca. Essa solução, em contato com os capilares do peritônio, permite o transporte difuso de solutos e a perda de água por ultrafiltração osmótica, uma vez que é hiperosmolar ao plasma devido à adição de agentes osmóticos (normalmente, a glicose). A infusão e drenagem da solução dentro da cavidade peritoneal pode ser realizada de duas maneiras: manualmente (DP ambulatorial contínua), em que o paciente, geralmente, passa por quatro trocas de solução durante o dia, ou por DP mecânica (automatizada), em que a diálise é realizada com o auxílio de uma máquina de diálise que permite que as trocas sejam feitas durante a noite, enquanto o paciente está dormindo. A prescrição e o acompanhamento da DP envolvem a caracterização do tipo de transporte peritoneal e a avaliação da dose de diálise oferecida (depuração do soluto), bem como o diagnóstico e tratamento de possíveis complicações relacionadas ao método (infecciosas e não infecciosas).

Benefits of a Continuous Ambulatory Peritoneal Dialysis (CAPD) Technique with One Icodextrin-Containing and Two Biocompatible Glucose-Containing Dialysates for Preservation of Residual Renal Function and Biocompatibility in Incident CAPD Patients

In a prospective randomized controlled study, the efficacy and safety of a continuous ambulatory peritoneal dialysis (CAPD) technique has been evaluated using one icodextrin-containing and two glucose-containing dialysates a day. Eighty incident CAPD patients were randomized to two groups; GLU group continuously using four glucose-containing dialysates (n=39) and ICO group using one icodextrin-containing and two glucose-containing dialysates (n=41). Variables related to residual renal function (RRF), metabolic and fluid control, dialysis adequacy, and dialysate effluent cancer antigen 125 (CA125) and interleukin 6 (IL-6) levels were measured. The GLU group showed a significant decrease in mean renal urea and creatinine clearance (-Delta1.2+/-2.9 mL/min/1.73 m2, P=0.027) and urine volume (-Delta363.6+/-543.0 mL/day, P=0.001) during 12 months, but the ICO group did not (-Delta0.5+/-2.7 mL/min/1.73 m2, P=0.266; -Delta108.6+/-543.3 mL/day, P=0.246). Peritoneal glucose absorption and dialysate calorie load were significantly lower in the ICO group than the GLU group. The dialysate CA125 and IL-6 levels were significantly higher in the ICO group than the GLU group. Dialysis adequacy, beta2-microglobulin clearance and blood pressure did not differ between the two groups. The CAPD technique using one icodextrin-containing and two glucose-containing dialysates tends to better preserve RRF and is more biocompatible, with similar dialysis adequacy compared to that using four glucose-containing dialysates in incident CAPD patients. [Clincal Trial Registry, ISRCTN23727549]

Benefits of a Continuous Ambulatory Peritoneal Dialysis (CAPD) Technique with One Icodextrin-Containing and Two Biocompatible Glucose-Containing Dialysates for Preservation of Residual Renal Function and Biocompatibility in Incident CAPD Patients

In a prospective randomized controlled study, the efficacy and safety of a continuous ambulatory peritoneal dialysis (CAPD) technique has been evaluated using one icodextrin-containing and two glucose-containing dialysates a day. Eighty incident CAPD patients were randomized to two groups; GLU group continuously using four glucose-containing dialysates (n=39) and ICO group using one icodextrin-containing and two glucose-containing dialysates (n=41). Variables related to residual renal function (RRF), metabolic and fluid control, dialysis adequacy, and dialysate effluent cancer antigen 125 (CA125) and interleukin 6 (IL-6) levels were measured. The GLU group showed a significant decrease in mean renal urea and creatinine clearance (-Delta1.2+/-2.9 mL/min/1.73 m2, P=0.027) and urine volume (-Delta363.6+/-543.0 mL/day, P=0.001) during 12 months, but the ICO group did not (-Delta0.5+/-2.7 mL/min/1.73 m2, P=0.266; -Delta108.6+/-543.3 mL/day, P=0.246). Peritoneal glucose absorption and dialysate calorie load were significantly lower in the ICO group than the GLU group. The dialysate CA125 and IL-6 levels were significantly higher in the ICO group than the GLU group. Dialysis adequacy, beta2-microglobulin clearance and blood pressure did not differ between the two groups. The CAPD technique using one icodextrin-containing and two glucose-containing dialysates tends to better preserve RRF and is more biocompatible, with similar dialysis adequacy compared to that using four glucose-containing dialysates in incident CAPD patients. [Clincal Trial Registry, ISRCTN23727549]

Low-calcium peritoneal dialysis solution is effective in bringing PTH levels to the range recommended by current guidelines in patients with PTH levels < 150 pg/dL / Alteração do teor de cálcio no banho de DP para 2, 5 mEq/L é eficaz no reestabelecimento dos valores preconizados por diretrizes atuais em pacientes com PTH < 150 pg/dL

INTRODUÇÃO/OBJETIVO: A doença óssea adinâmica (DOA) é um achado comum em diálise peritoneal (PD) e é considerada fator de risco para desenvolvimento de fraturas e doença cardiovascular. Dados do BRAZPD apontam as soluções de cálcio a 3,5 mEq/L presentes na maioria das prescrições no país, que possui quase 9.000 pacientes em PD. É comum o balanço positivo de cálcio com concentrações a 3,5 mEq/L contribuindo para o desenvolvimento de DOA. Diretrizes atuais recomendam um PTHi na DRC V em diálise entre 2 e 9 vezes (150-500 pg/mL) o valor máximo da normalidade. O objetivo deste estudo foi avaliar a resposta em 6 meses do PTH-i após a conversão para solução de cálcio a 2,5 mEq/L de pacientes que usavam soluções com cálcio a 3,5 mEq/L e com PTH-i basal < 150 pg/mL. MÉTODOS: Coorte prospectiva, observacional, na qual todos pacientes prevalentes em PD entre janeiro de 2008 e janeiro de 2009 de um único centro foram incluídos. Critérios de inclusão foram:(1) estar em uso de solução de DP com cálcio a 3,5 mEq/L; (2)PTH sérico < 150 pg/mL. A critério médico, os pacientes poderiam ser convertidos ou não para soluções cálcio a 2,5 mEq/L. RESULTADOS: 35 pacientes (idade média 62 ± 17 anos) foram incluídos. Desses, 22 foram convertidos para solução de cálcio 2,5 mEq/L. Nefropatia diabética foi a principal doença de base (36 por cento) seguido por HAS (25 por cento) e GNC (14 por cento). Os grupos apresentavam valores basais semelhantes de PTH, cálcio, fósforo e fosfatase alcalina. No grupo-intervenção, houve aumento significativamente maior de PTH em 6 meses comparado com o grupo-controle (Δ194 pg/dL versus Δ 92/dL; p < 0,05).

INTRODUCTION/OBJECTIVE: Adinamic bone disease (ABD) is a common finding in peritoneal dialysis (PD) and is associated with higher risk of developing cardiovascular and bone disease. Data from BRAZPD indicates that 3.5 mEq/L calcium PD solutions represents the majority of PD prescriptions in the country. A positive calcium balance can contribute to ABD development. Currently guidelines suggest that PTH-i levels in end stage renal disease should be kept from 150-300 pg/mL. The purpose of this study is to evaluate 6 month PTH-i response after conversion to 2.5 mEq/L calcium PD solution in patients with baseline PTH-i levels < 150 pg/mL. METHODS: Prospective, observational study of all prevalent patients (at least 90 days on therapy) on PD of a single Brazilian center from January 2008 to May 2009. Inclusion criteria (1) be in use of a PD solution with 3.5mEq/L of calcium; (2) baseline PTH leves < 150 pg/ mL. According to clinical practice patients could be switched to PD solutions with 2.5 mEq/L of calcium. RESULTS: 35 patients (age 62 ± 17 years) were included. Of these 22 were converted to 2.5 mEq/L calcium solutions. Diabetic nephropathy (36 percent) was the main cause of renal disease followed by nephrosclerosis (25 percent) and glomerulonephritis (14 percent). Converted group presented a greater increase in PTH levels when compared with the control group (Δ194 pg/dL versus Δ 92/dL; p < 0,05). Among patients switched to low calcium solution, 41 percent reached the target values (PTH 150300 pg/mL) compared to 14 percent whose remain with normal calcium solutions (p < 0.05). There were no differences between groups regarding calcium, phosphorus and alkaline phosphatase. CONCLUSION: In patients with PTH < 150 pg/mL conversion to low calcium solutions (2.5 mEq/L) appears to be a simple and effective strategy to bring PTH levels to the range determined by current guidelines when compared with 3.5mEq/L calcium PD solutions.

High Peritoneal Transport Status is Not an Independent Risk Factor for High Mortality in Patients Treated with Automated Peritoneal Dialysis

We undertook this study to elucidate whether baseline peritoneal membrane transport characteristics are associated with high mortality in incident automated peritoneal dialysis (APD) patients. This retrospective study includes 117 patients who started APD at Yonsei University Health System from 1996 to 2008 and had a PET within 3 months of APD initiation. High transporters were significantly older and had a higher incidence of cardiovascular disease. Patient survival for years 1, 3, and 5 were 85%, 64%, and 35% for high transporter and 94%, 81%, and 68% for non-high transporter group (P<0.01). Multivariate analysis revealed that age, diabetes, cardiovascular disease, serum albumin level, and residual renal function were independently associated with high mortality in APD patients. In contrast, high transport status was not a significant predictor for mortality in this population when the other covariates were included. Even though high transport was significantly associated with mortality in the univariate analysis, its role seemed to be influenced by other comorbid conditions. These findings suggest that the proper management of these comorbid conditions, as well as appropriate ultrafiltration by use of APD and/or icodextrin, must be considered as protective strategies to improve survival in peritoneal dialysis patients with high transport.

Avaliação da eficiência dialítica através da quantificação direta do dialisato em pacientes com insuficiência renal aguda submetidos à hemodiálise prolongada / Evaluation of dialysis efficiency by direct dialysate quantificationin acute renal failure patients submitted to extended hemodialysis

Introdução: A melhor forma de quantificar a dose de diálise em pacientes com insuficiência renal aguda (IRA) ainda não está estabelecida. O b j e t i v o s :Avaliar a dose de diálise recebida pela maneira tradicional (PRU e Kt/V) e através da quantificação direta do dialisato em pacientes com IRA. M é t o d o s :A dose de diálise foi quantificada pelo percentual de redução de uréia (PRU), Kt/V (spKt/V e eKt/V) e massa extraída de uréia no dialisato (coleta parcialpor dispositivo automatizado) em pacientes com IRA submetidos à hemodiálise prolongada em unidade de terapia intensiva (UTI). Pacientes cominsuficiência renal crônica (IRC) em programa de diálise serviram como grupo controle. Resultados: Foram realizadas 11 sessões de hemodiáliseprolongada em 8 pacientes com IRA e 8 sessões de hemodiálise convencional em 5 pacientes com IRC. O PRU foi maior nos pacientes com IRC (67%;62-74% v s 54%; 37-57%; P<0,01), assim como o spKt/V (1,31;1,15-1,62 vs 0,90;0,55-1,01; P<0,01) e o eKt/V (1,15; 1,03-1,44 vs 0,69;0,47-0,92; P<0,01).Não houve diferença com relação à massa extraída de uréia no dialisato entre as sessões de hemodiálise convencional (32,6 g; 24,4-56,1) e prolongada(31,8 g; 18,2-88,8). Conclusões: Apesar da maior dose de diálise recebida nos pacientes com IRC, quando avaliada pelo PRU e Kt/V, não houvediferença na massa extraída de uréia no dialisato. Possivelmente, os valores de normalidade definidos pelo método clássico de cinética de uréia parapacientes com IRC não se aplicam a pacientes com IRA e a aferição da dose de diálise pelo dialisato pode ser uma alternativa viável nestes pacientes.

Introduction: The best way for dialysis quantification in patients with acute renal failure (ARF) is not defined. Objectives: Evaluate the delivered dialysisdose by the traditional methods (URR and Kt/V) and by the direct dialysate quantification in patients with acute renal failure. Methods: The dialysis dosewas measured by urea reduction rate (URR), Kt/V (spKt/V, eKt/V) and urea extracted mass in the dialysate (partial dialysate collection by automatic device)in acute renal failure (ARF) patients submitted to extended dialysis in intensive care unit (ICU). Chronic renal failure (CRF) patients were the control group.Results: Eleven extended hemodialysis sessions in eight patients with ARF and eight conventional hemodialysis sessions in five CRF patients wereevaluated. The URR was higher in CRF patients (67%; 62-74% vs 54%; 37-57%; P<0.01) as the spKt/V (1.31;1.15-1.62 vs 0.90;0.55-1.01; P<0.01) andeKt/V (1.15; 1.03-1.44 vs 0.69;0.47-0.92; P<0.01). There was no difference regarding the urea extracted mass in the dialysate in the conventional (32.6 g;24.4-56.1) and extended hemodialysis (31.8 g; 18.2-88.8). Conclusions: In spite of CRF patients have received a higher dialysis dose when evaluated byURR and Kt/V, there was no difference in the urea extracted mass in the dialysate. The classical urea kinetic model may be not applicable for ARF patientsand the evaluation of the dialysate can be an alternative for measurement of dialysis dose in these patients.

Gasometria y tolerancia clínica de los pacientes durante hemodiálisis con baños de bicarbonato y de acetato de sodio / Gasometry and clinical tolerance of patients during hemodyalisis with sodium and acetate

La hemodialisis es mas fisiológica cuando se usa baño de bicarbonato en vez de acetato y las nuevas técnicas de hemodialisis (alta eficiencia y alto flujo), requieren el uso de estos baños. La influencia de los cambios en la gasometria sobre la sintomatologia en hemodialisis de pacientes con caracteristicas especiales, no ha sido adecuadamente descrita. En el presente trabajo comparamos la evolución de la gasometria arterial en un grupo de 56 hemodialisis realizadas en 14 pacientes(7 altamente sintomaticos y 7 oligosintomaticos) tratados en dos sesiones con baños de bicarbonato y dos con baños de acetato de 3 horas cada una. Tambien se comparo la sintomatologia y tolerancia hemodinamica de los pacientes cuando se dializaron con las dos soluciones. Encontramos una corrección mas temprana del pH y la bicarbonetemia y un grado de hipoxemia significativamente menor en los pacientes dializados con baños de bicarbonato. En ellos fue mejor la tolerancia sintomatológica y hemodinamica al proceso dialitico