When is dialysis indicated in acute kidney injury?

The indications for dialysis in patients with acute kidney injury (AKI), as well as the dose and timing of initiation, remain uncertain. Recent data have suggested that early initiation of renal replacement therapy (RRT) may be associated with decreased mortality but not with the recovery of kidney function. A blood urea nitrogen (BUN) level of 75 mg/dL is a useful indicator for dialysis in asymptomatic patients, but one that is based on studies with limitations. Different parameters, including absolute and relative indicators, are needed. Currently, nephrologists should consider the trajectory of disease, and the clinical condition and prognosis of the patient are more important than numerical values in the decision to initiate dialysis.

Continuous peritoneal dialysis compared with daily hemodialysis in patients with acute kidney injury.

BACKGROUND: In some parts of the world, peritoneal dialysis is widely used for renal replacement therapy (RRT) in acute kidney injury (AKI), despite concerns about its inadequacy. It has been replaced in recent years by hemodialysis and, most recently, by continuous venovenous therapies. We performed a prospective study to determine the effect of continuous peritoneal dialysis (CPD), as compared with daily hemodialysis (dHD), on survival among patients with AKI. METHODS: A total of 120 patients with acute tubular necrosis (ATN) were assigned to receive CPD or dHD in a tertiary-care university hospital. The primary endpoint was hospital survival rate; renal function recovery and metabolic, acid-base, and fluid controls were secondary endpoints. RESULTS: Of the 120 patients, 60 were treated with CPD (G1) and 60 with dHD (G2). The two groups were similar at the start of RRT with respect to age (64.2 +/- 19.8 years vs 62.5 +/- 21.2 years), sex (men: 72% vs 66%), sepsis (42% vs 47%), shock (61% vs 63%), severity of AKI [Acute Tubular Necrosis Individual Severity Score (ATNISS): 0.68 +/- 0.2 vs 0.66 +/- 0.22; Acute Physiology and Chronic Health Evaluation (APACHE) II: 26.9 +/- 8.9 vs 24.1 +/- 8.2], pre-dialysis blood urea nitrogen [BUN (116.4 +/- 33.6 mg/dL vs 112.6 +/- 36.8 mg/dL)], and creatinine (5.85 +/- 1.9 mg/dL vs 5.95 +/- 1.4 mg/dL). In G1, weekly delivered Kt/V was 3.59 +/- 0.61, and in G2, it was 4.76 +/- 0.65 (p < 0.01). The two groups were similar in metabolic and acid-base control (after 4 sessions, BUN < 55 mg/dL: 46 +/- 18.7 mg/dL vs 52 +/- 18.2 mg/dL; pH: 7.41 vs 7.38; bicarbonate: 22.8 +/- 8.9 mEq/L vs 22.2 +/- 7.1 mEq/L). Duration of therapy was longer in G2 (5.5 days vs 7.5 days; p = 0.02). Despite the delivery of different dialysis methods and doses, the survival rate did not differ between the groups (58% in G1 vs 52% in G2), and recovery of renal function was similar (28% vs 26%). CONCLUSION: High doses of CPD provided appropriate metabolic and pH control, with a rate of survival and recovery of renal function similar to that seen with dHD. Therefore, CPD can be considered an alternative to other forms of RRT in AKI.

Utilization of peritoneal dialysis in the acute setting.

Peritoneal dialysis (PD), although classically described and utilized in the treatment of patients with end-stage renal disease, can also be utilized in the acute setting in different clinical situations. Recent studies showed that, in patients with acute renal failure, it is possible to obtain reasonable dialysis doses with adequate metabolic and electrolytic control and low incidence of complications by utilizing continuous PD through a cycler at high volume. In patients with congestive heart failure without end-stage renal disease, PD is capable of promoting clinical improvement with slow removal of liquids, becoming an attractive alternative for situations of rapidly or slowly worsening cardiac function. In patients submitted to chronic hemodialysis but who have vascular access difficulties, PD can also be utilized as a "bridge," thereby avoiding the use of central venous catheters, which can be associated with infectious complications such as bacterial endocarditis. New studies must be realized showing other indications for PD.

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.

[Assessment of mortality and specific index in acute renal failure]. / Mortalidade e prognóstico específico em pacientes com insuficiência renal aguda.

UNLABELLED: A variety of systems of risk factor stratification have been studied to predict the outcome in acute renal failure (ARF). OBJECTIVES: Assess and compare mortality and the Acute Tubular Necrosis Individual Severity Score (ATN-ISS) in patients with AFR treated in a university hospital. METHODS: A prospective analysis was made of 103 patients with a diagnosis of intrinsic ARF admitted to the Hospital das Clinicas da Faculdade de Medicina de Botucatu, UNESP. Patients were followed up until recovery of renal function or death. The Score ATN-ISS was recorded during the first hours of the assessment by a nephrologist. Results were reported as median or mean +/- SD, with statistical significance of p < 0.05. RESULTS: Fifty-one percent of patients were male with a mean age of 58 +/- 36 years. Forty-four percent died in the hospital. Mortality was higher in patients from the surgical wards (52.7%) and in patients who were treated with dialysis (63.8%). The score ATN-ISS showed a good confidence level, with high discriminatory power (area under the curve of 0.95) and good accuracy. CONCLUSIONS: Mortality in this study was comparable to that found in literature. The ATN-ISS was shown to be a prognostic index with a high confidence level that could be routinely applied by nephrologists to patients with AFR.

Peritoneal dialysis in acute renal failure.

The definition of adequate dialysis in acute renal failure (ARF) is complex and involves the time of referral to dialysis, dose, and dialytic method. Nephrologist experience with a specific procedure and the availability of different dialysis modalities play an important role in these choices. There is no consensus in literature on the best method or ideal dialysis dose in ARF. Peritoneal dialysis (PD) is used less and less in ARF patients, and is being replaced by continuous venovenous therapies. However, it should not be discarded as a worthless therapeutic option for ARF patients. PD offers several advantages over hemodialysis, such as its technical simplicity, excellent cardiovascular tolerance, absence of an extracorporeal circuit, lack of bleeding risk, and low risk of hydro-electrolyte imbalance. PD also has some limitations, though: it needs an intact peritoneal cavity, carries risks of peritoneal infection and protein losses, and has an overall lower effectiveness. Because daily solute clearance is lower with PD than with daily HD, there have been concerns that PD cannot control uremia in ARF patients. Controversies exist concerning its use in patients with severe hypercatabolism; in these cases, daily hemodialysis or continuous venovenous therapy have been preferred. There is little literature on PD in ARF patients, and what exists does not address fundamental parameters such as adequate quantification of dialysis and patient catabolism. Given these limitations, there is a pressing need to re-evaluate the adequacy of PD in ARF using accepted standards. Therefore, new studies should be undertaken to resolve these problems.

Influência do treinamento na evolução da diálise peritoneal / Influence of training on the progression of peritoneal dialysis

Objetivo: Conhecer a influência do cuidador no treinamento da diálise peritoneal (DP) e no tempo livre de peritonite. Método: Estudo retrospectivo com 38 pacientes prevalentes, atendidos na Diálise Ambulatorial do Hospital das Clínicas/Botucatu, que receberam treinamento para DP pela mesma enfermeira. Avaliaram-se: 1) o responsável pela técnica de diálise (paciente ou cuidador); 2) o treinamento (tempo dispensado e desempenho atingido); 3) o tempo livre de peritonite. Foram realizadas regressão logística e análise de sobrevivência por Kaplan-Meyer. Resultado: A DP foi realizada por umcuidador em 71% (N=27) dos pacientes. Dos diabéticos, 89% (N=16) necessitavam de cuidador e 11% (N=2) realizaram o próprio tratamento (p<0,05); quanto à idade, 26% (N=10) apresentavam mais de 65 anos e, destes, 90% (N=9) tinham o cuidador para DP (p=0,05); dos pacientes provenientes de outras localidades (N=23), 74% (N=17) necessitavam do cuidador (p=0,07). O treinamento foi concluído no tempo médio por 71% (N=27), e 79% (N=30) obtiveram desempenho bom, sem diferenças quanto ao responsável pela técnica. A probabilidade de permanecer livre de peritonite no primeiro ano detratamento foi maior quando o cuidador realizava a DP, sendo 54% para o paciente e 78% para o cuidador (p<0,05). Conclusão: Pacientes com mais de 65 anos e diabéticos necessitaram de cuidador na diálise. No treinamento, tempo dispensado e desempenho atingido não diferiram quanto ao responsável pela técnica. O tempo livre de peritonite foi maior para os pacientes em que a diálise foi realizada por cuidador. O responsável pela diálise (paciente ou cuidador) pode influenciar na evolução da DP.

Objective: To evaluate the influence of the caretaker on the training time of peritoneal dialysis (PD) and peritonitis-free time. Method: Retrospective medical record review of 38 patients receiving PD training from the same nurse at the Dialysis Unit of Botucatu Medical School Hospital. Assessment included: 1) home PD provider (patient or caretaker); 2) training (length and performance achieved); 3) peritonitis-free time. Result: In 71% (N=27) of the cases, PD was performed by a caretaker. Among diabetic patients, 89% (N=16) were supported by a caretaker, and 11 % (N=2) performed their own dialysis (p=0.03); 26% (N=10) were over 65 years of age, with 90% (N=10) of them having a PD caretaker (p=0.05). Among patients from other areas (N=23), 74% (N=17) were supported by a PD caretaker (p=0.07). Training was concluded after the mean time by 71% (N=27) and a good performance level was achieved in 79% (N=30) of the cases with no difference between provider type. The probability of the patient remaining peritonitis-free over the first year was higher when PD was performed by a caretaker (patient= 54%; caretaker = 78%; p<0.05). Conclusion: The presence of caretakers was more frequent among the patients who were over 65 years of age or diabetic. With respect to training, length of time and performance did not differ according to the person responsible for technique. Peritonitis-free time was longer among patients supported by caretakers. The PD provider (patient or caretaker) may influence PD results.

Mortalidade e prognóstico específico em pacientes com insuficiência renal aguda / Assessment of mortality and specific index in acute renal failure

Vários sistemas de estratificação de risco têm sido estudados com o objetivo de predizer a evolução de pacientes graves com insuficiência renal aguda (IRA). OBJETIVOS: Avaliar e comparar as taxas de mortalidade e o escore de severidade individual de necrose tubular aguda (ATN-ISS) em pacientes que desenvolveram IRA tratados em hospital universitário de atendimento predominantemente terciário. MÉTODOS: Foram estudados prospectivamente 103 pacientes com IRA por necrose tubular aguda (NTA), atendidos no Hospital das Clínicas da Faculdade de Medicina de Botucatu - UNESP, acompanhados até recuperação do quadro renal ou óbito. No momento da primeira avaliação do nefrologista foi aplicado o escore ATN-ISS. Os resultados foram apresentados em média ± desvio padrão ou mediana, com nível de significância de 5 por cento. RESULTADOS: Verificamos que 51,4 por cento eram do sexo masculino, com média de idade de 58 ± 36 anos. A mortalidade geral foi de 44,3 por cento, sendo estatisticamente maior nos pacientes provenientes de enfermarias cirúrgicas (52,7 por cento) quando comparados àqueles de enfermarias clínicas (35,3 por cento), e naqueles que realizaram diálise (63,8 por cento) quando comparados aos de tratamento conservador (23,5 por cento). O escore ATN-ISS apresentou boa confiabilidade, com elevado poder discriminatório (área sob a curva de 0,95) e boa calibração, principalmente a partir do quintil 3. CONCLUSÃO: Na população estudada, as taxas de mortalidade foram semelhantes àquelas encontradas na literatura. O escore ATN-ISS mostrou ser um índice prognóstico com grande confiabilidade, podendo ser aplicado na prática diária do nefrologista.

Sobrevida em hemodiálise no hospital das clínicas da faculdade de medicina de Botucatu Unesp: comparação entre a primeira e a segunda metades da década de 90 / Hemodialysis Survival at the Hospital das Clínicas da Faculdade de Medicina de Botucatu - Unesp: Comparison Between The First and Second Halves of the 1990Æs

Comparar a sobrevida em hemodiálise da primeira com a segunda metades da década de 90. Método: Foram avaliados 153 renais crônicos tratados exclusivamente por hemodiálise no Hospital das Clínicas da Faculdade de Medicina de Botucatu no período de março de 1990 a março de 2000, comparando a sobrevida entre a primeira (Grupo 1; n= 75) e a segunda (Grupo 2; n= 78) metades da década, sendo que a primeira metade estava claramente relacionada à menor utilização de recursos tecnológicos como diálises em máquinas de tanque, banho contendo acetato como tampão e tratamento de água feito por deionizador. Na segunda metade, a maioria das máquinas era de proporção com ultrafiltração controlada, dialisato contendo bicarbonato e tratamento da água por osmose reversa. Resultados: A sobrevida global foi de 77% em um ano e de 58% em 5 anos. Esses valores foram de 78% e 57% para o Grupo 1 e 79% e 61% para o Grupo 2. Não houve diferença estatisticamentesignificante quanto à sobrevida entre as duas metades da década, mesmo quando corrigida para os principais fatores de risco: idade e presença de diabetes. Conclusões: Não pudemos observar melhora na sobrevida apesar da incorporação de novas tecnologias, ocorrida principalmente na segunda metade da década, o que não exclui que a morbidade pudesse ter melhorado.(au)