Abstract Introduction: Acute kidney injury (AKI) is a frequent complication of severe COVID-19 and is associated with high case fatality rate (CFR). However, there is scarcity of data referring to the CFR of AKI patients that underwent kidney replacement therapy (KRT) in Brazil. The main objective of this study was to describe the CFR of critically ill COVID-19 patients treated with acute kidney replacement therapy (AKRT). Methods: Retrospective descriptive cohort study. We included all patients treated with AKRT at an intensive care unit in a single tertiary hospital over a 15-month period. We excluded patients under the age of 18 years, patients with chronic kidney disease on maintenance dialysis, and cases in which AKI preceded COVID-19 infection. Results: A total of 100 out of 1479 (6.7%) hospitalized COVID-19 patients were enrolled in this study. The median age was 74.5 years (IQR 64 – 82) and 59% were male. Hypertension (76%) and diabetes mellitus (56%) were common. At the first KRT prescription, 85% of the patients were on invasive mechanical ventilation and 71% were using vasoactive drugs. Continuous veno-venous hemodiafiltration (CVVHDF) was the preferred KRT modality (82%). CFR was 93% and 81 out of 93 deaths (87%) occurred within the first 10 days of KRT onset. Conclusion: AKRT in hospitalized COVID-19 patients resulted in a CFR of 93%. Patients treated with AKRT were typically older, critically ill, and most died within 10 days of diagnosis. Better strategies to address this issue are urgently needed.

Resumo Introdução: Injúria renal aguda (IRA) é uma complicação frequente da COVID-19 grave e está associada a alta taxa de letalidade (TL). Entretanto, há escassez de dados referentes à TL de pacientes com IRA submetidos a suporte renal artificial (SRA) no Brasil. O objetivo principal deste estudo foi descrever a TL de pacientes graves com IRA por COVID-19 tratados com SRA. Métodos: Estudo de coorte descritivo retrospectivo. Incluímos todos os pacientes tratados com SRA em unidade de terapia intensiva de um único hospital terciário por 15 meses. Excluímos pacientes menores de 18 anos, pacientes com doença renal crônica em diálise de manutenção e casos nos quais a IRA precedeu a infeção por COVID-19. Resultados: Incluímos neste estudo um total de 100 dos 1479 (6,7%) pacientes hospitalizados com COVID-19. A mediana de idade foi 74,5 anos (IIQ 64 – 82) e 59% eram homens. Hipertensão (76%) e diabetes mellitus (56%) foram comuns. Na primeira prescrição de SRA, 85% dos pacientes estavam em ventilação mecânica invasiva e 71% em uso de drogas vasoativas. A hemodiafiltração contínua foi a modalidade de SRA preferida (82%). A TL foi de 93% e 81 dos 93 óbitos (87%) ocorreram nos primeiros 10 dias do início da SRA. Conclusão: O SRA em pacientes hospitalizados com IRA por COVID-19 resultou em TL de 93%. Os pacientes tratados com SRA eram geralmente idosos, gravemente enfermos e a maioria foi a óbito em até 10 dias após o diagnóstico. Estratégias melhores para abordar esse problema são urgentemente necessárias.

ABSTRACT Background: Rapid correction of hyponatremia, especially when severe and chronic, can result in osmotic demyelination. The latest guideline for diagnosis and treatment of hyponatremia (2014) recommends a correction limit of 10 mEq/L/day. Our aim was to summarize published cases of osmotic demyelination to assess the adequacy of this recommendation. Method: Systematic review of case reports of osmotic demyelination. We included cases confirmed by imaging or pathology exam, in people over 18 years of age, published between 1997 and 2019, in English or Portuguese. Results: We evaluated 96 cases of osmotic demyelination, 58.3% female, with a mean age of 48.2 ± 12.9 years. Median admission serum sodium was 105 mEq/L and > 90% of patients had severe hyponatremia (<120 mEq/L). Reports of gastrointestinal tract disorders (38.5%), alcoholism (31.3%) and use of diuretics (27%) were common. Correction of hyponatremia was performed mainly with isotonic (46.9%) or hypertonic (33.7%) saline solution. Correction of associated hypokalemia occurred in 18.8%. In 66.6% of cases there was correction of natremia above 10 mEq/L on the first day of hospitalization; the rate was not reported in 22.9% and in only 10.4% was it less than 10 mEq/L/day. Conclusion: The development of osmotic demyelination was predominant in women under 50 years of age, with severe hyponatremia and rapid correction. In 10.4% of cases, there was demyelination even with correction <10 mEq/L/day. These data reinforce the need for conservative targets for high-risk patients, such as 4–6 mEq/L/day, not exceeding the limit of 8 mEq/L/day.

RESUMO Antecedentes: A correção rápida da hiponatremia, principalmente quando grave e crônica, pode resultar em desmielinização osmótica. A última diretriz para diagnóstico e tratamento da hiponatremia (2014) recomenda um limite de correção de 10 mEq/L/dia. Nosso objetivo foi sumarizar os casos publicados de desmielinização osmótica para avaliar a adequação dessa recomendação. Método: Revisão sistemática de relatos de caso de desmielinização osmótica. Incluímos casos confirmados por imagem ou anatomia patológica, em maiores de 18 anos, publicados entre 1997 e 2019, nas línguas inglesa ou portuguesa. Resultados: Avaliamos 96 casos de desmielinização osmótica, sendo 58,3% do sexo feminino e com média de idade de 48,2 ± 12,9 anos. A mediana de sódio sérico admissional foi 105 mEq/L e > 90% dos pacientes apresentavam hiponatremia grave (<120 mEq/L). Foram comuns os relatos de distúrbios do trato gastrointestinal (38,5%), etilismo (31,3%) e uso de diuréticos (27%). A correção da hiponatremia foi feita principalmente com solução salina isotônica (46,9%) ou hipertônica (33,7%). Correção de hipocalemia associada ocorreu em 18,8%. Em 66,6% dos casos houve correção da natremia acima de 10 mEq/L no primeiro dia de internamento; a velocidade não foi relatada em 22,9% e em apenas 10,4% foi menor que 10 mEq/L/dia. Conclusão: O desenvolvimento da desmielinização osmótica foi predominante em mulheres, abaixo de 50 anos, com hiponatremia grave e correção rápida. Em 10,4% dos casos, houve desmielinização mesmo com correção <10 mEq/L/dia. Esses dados reforçam a necessidade de alvos conservadores para pacientes de alto risco, como 4–6 mEq/L/dia, não ultrapassando o limite de 8 mEq/L/dia.

OBJECTIVES: Positive fluid balance is frequent in critically ill patients and has been considered a potential biomarker for acute kidney injury (AKI). This study aimed to evaluate positive fluid balance as a biomarker for the early detection of AKI in critically ill patients. METHODS: This was a prospective cohort study. The sample was composed of patients ≥18 years old who stayed ≥3 days in an intensive care unit. Fluid balance, urinary output and serum creatinine were assessed daily. AKI was diagnosed by the Kidney Disease Improving Global Outcome criteria. RESULTS: The final cohort was composed of 233 patients. AKI occurred in 92 patients (40%) after a median of 3 (2-6) days following ICU admission. When fluid balance was assessed as a continuous variable, a 100-ml increase in fluid balance was independently associated with a 4% increase in the odds of AKI (OR 1.04; 95% CI 1.01-1.08). Positive fluid balance categorized using different thresholds was always significantly associated with subsequent detection of AKI. The mixed effects model showed that increased fluid balance preceded AKI by 4 to 6 days. CONCLUSION: These results suggest that a positive fluid balance might be an early biomarker for AKI development in critically ill patients.

Abstract Background: Despite the efficacy of vitamin K antagonists against stroke in patients with atrial fibrillation (AF), the underuse of this therapy is well documented. Objectives: To evaluate trends and predictors of oral anticoagulants utilization in patients with AF. Methods: Observational, retrospective, serial cross-sectional study between 2011-2016. Comparisons between groups were performed using the Student t, Mann-Whitney and Chi-square tests. Logistic regression was used to identify independent predictors of anticoagulation. A p value < 0.05 was considered significant. Results: A total of 377 patients were analyzed. The mean age was 70 ± 15 years; 52% were male and 75% were anticoagulated (20% with VKA and 55% with DOAC). Over 5 years, the overall frequency of anticoagulation increased by 22.4%. The use of DOACs increased from 29% to 70%, whereas the use of VKA decreased from 36% to 17%. The use of antiplatelet agents alone also fell from 21% to 6%. The predictors of anticoagulation were previous episodes of AF (OR 3.1, p < 0.001), hypertension (OR 3.0, p < 0.001) and HASBLED score (OR 0.5, p < 0.001). The predictors of DOAC use were serum creatinine (OR 0.2, p = 0.002), left atrial size (OR 0.9, p = 0.003) and biological valve prosthesis (OR 0.1, p = 0.007). Of the 208 patients using DOACs, 63 (30%) received inadequate prescriptions: 5 with severe drug interactions and 58 with incorrect dosing. Conclusions: Between 2011 and 2016, DOACs were rapidly incorporated into clinical practice, replacing AVKs and antiplatelets, and contributing to greater use of anticoagulation in patients with AF.

Abstract INTRODUCTION: Bowel dysfunction is frequent in patients with spinal cord diseases, but little is known about the prevalence of bowel symptoms in human T-lymphotropic virus-(HTLV-1) infected individuals. The purpose of this study is to determine the frequency of bowel symptoms in HTLV-1 infected individuals and their correlation with the degree of neurologic disease. METHODS: This is a cross-sectional study comparing the frequency of bowel symptoms in HTLV-1-infected individuals* and seronegative donors (controls). Patients answered a questionnaire, the Rome III Criteria was applied, and stool consistency was evaluated by the Bristol Stool Form Scale. The individuals were classified as HTLV-1 carriers, probable HTLV-1 myelopathy and definitive HTLV-1 associated myelopathy or tropical spastic paraparesis (definitive HAM / TSP)**. RESULTS: We studied 72 HTLV-1 infected individuals and 72 controls with equal age and gender distribution. Constipation was the most frequent complaint, occurring in 38 % of HTLV-1 individuals and in 15 % of the controls. In comparison to the seronegative controls, the probability of constipation occurrence was approximately 18 times higher in definitive HAM / TSP patients. Straining, lumpy or hard stools, sensation of anorectal obstruction/blockage, fewer than 3 defecations per week, flatulence, soiling, evacuation pain, and bleeding were also more frequent in the HTLV-1 patients than in the controls. Moreover, bowel symptoms were more frequent in patients with definitive or probable HAM / TSP than in carriers. CONCLUSIONS: Bowel symptoms were more frequent in HTLV-1-infected patients than in seronegative controls and the frequency of bowel symptoms correlated with the severity of neurologic disease.

Introdução: A sepse é considerada importante causa de Lesão Renal Aguda (LRA) em pacientes internados em Unidade de Terapia Intensiva (UTI), sendo esta síndrome associada à elevada mortalidade. Objetivo: Avaliar os fatores de risco para diálise e mortalidade em uma coorte de pacientes com LRA de etiologia predominantemente séptica. Métodos: Pacientes adultos com LRA internados em UTI avaliados pela equipe da nefrologia, sendo excluídos portadores de doença renal crônica terminal e transplantados renais. Resultados: 114 pacientes foram incluídos. A maioria apresentou sepse (84%), estágio AKIN 3 (69%) e oligúria (69%) na primeira consulta nefrológica. Diálise foi realizada em 66%; a mortalidade geral foi de 70%. A creatinina mediana nos sobreviventes e não sobreviventes foi 3,95 mg/dl (2,63 - 5,28) and 2,75 mg/dl (1,81 - 3,69). Nos modelos multivariáveis, oligúria e a ureia sérica foram positivamente associadas com diálise; entretanto, menor creatinina sérica na primeira consulta foi independentemente associada com maior mortalidade. Conclusão: Nesta coorte de pacientes com LRA de etiologia predominantemente séptica, oligúria e a ureia sérica foram as principais indicações de diálise. Também observamos associação inversa entre a creatinina sérica e mortalidade. Possíveis justificativas para esse achado são avaliação nefrológica tardia, sobrecarga volêmica com hemodiluição da creatinina sérica ou desnutrição. Este achado pode, ainda, ajudar a explicar o baixo poder discriminativo dos escores gerais de gravidade, que atribuem maior pontuação a valores maiores de creatinina, em pacientes críticos com LRA.

Introduction: Sepsis is a leading precipitant of Acute Kidney Injury (AKI) in intensive care unit (ICU) patients, and is associated with a high mortality rate. Objective: We aimed to evaluate the risk factors for dialysis and mortality in a cohort of AKI patients of predominantly septic etiology. Methods: Adult patients from an ICU for whom nephrology consultation was requested were included. End-stage chronic renal failure and kidney transplant patients were excluded. Results: 114 patients were followed. Most had sepsis (84%), AKIN stage 3 (69%) and oliguria (62%) at first consultation. Dialysis was performed in 66% and overall mortality was 70%. Median serum creatinine in survivors and non-survivors was 3.95 mg/dl (2.63 - 5.28) and 2.75 mg/dl (1.81 - 3.69), respectively. In the multivariable models, oliguria and serum urea were positively associated with dialysis; otherwise, a lower serum creatinine at first consultation was independently associated with higher mortality. Conclusion: In a cohort of septic AKI, oliguria and serum urea were the main indications for dialysis. We also described an inverse association between serum creatinine and mortality. Potential explanations for this finding include: delay in diagnosis, fluid overload with hemodilution of serum creatinine or poor nutritional status. This finding may also help to explain the low discriminative power of general severity scores - that assign higher risks to higher creatinine levels - in septic AKI patients.

Injúria renal aguda (IRA) é uma síndrome de elevada incidência, associada a altas taxas de morbimortalidade. Sepse, grandes cirurgias e baixo débito cardíaco são as principais causas de IRA no mundo. Na maioria destas situações clínicas, a expansão volêmica é o elemento fundamental de prevenção e do manejo terapêutico da IRA, restaurando a perfusão periférica e atenuando a nefrotoxicidade de drogas. Ressuscitação volêmica precoce em pacientes sépticos está associada à prevenção de isquemia tecidual e à maior sobrevida. Contudo, a manutenção de estratégia liberal de infusão de fluidos após ressuscitação inicial pode causar balanços hídricos cumulativamente positivos, e este vem sendo associado a aumento de morbimortalidade em pacientes criticamente enfermos. Neste trabalho, revisamos os principais estudos que associam balanço hídrico positivo (BH+) e morbimortalidade em pacientes internados em Unidades de Terapia Intensiva (UTI). Sugerimos que BH+ (não apenas o volume urinário) possa ser utilizado como possível biomarcador precoce de IRA nestes pacientes.

Acute kidney injury (AKI) has a high hospital incidence and is associated to significant morbidity and mortality. Sepsis, major surgery and low cardiac output are the main cause of AKI worldwide. In the majority of these situations, volume expansion is part of both prevention and therapeutic management, restoring peripheral perfusion and attenuating drug nephrotoxicity. Early and aggressive volume resuscitation in septic patients halts tissue ischemia and is associated with higher survival. However, a liberal fluid infusion strategy after six hours can cause fluid overload. Fluid overload has been associated with morbidity and mortality increase in critically ill patients. Herein, we present a review of the main studies that assessed the effects of net fluid balance/fluid overload on the morbidity and mortality of critically ill patients. We suggest that positive water balance may be used as a potential early biomarker of AKI in these patients.

Um rapaz de 19 anos, previamente hígido, procurou o hospital com queixas de anorexia, náuseas e vômitos. Exames laboratoriais revelaram hipercalcemia (valor máximo do cálcio de 14,8 mg/dL) e lesão renal aguda (valor máximo da creatinina de 2,88 mg/dL). O paciente admitiu utilizar uma formulação parenteral de vitaminas A, D e E de uso exclusivo veterinário, contendo 20.000.000 UI de vitamina A; 5.000.000 UI de vitamina D3 e 6.800 UI de vitamina E, por ampola de 100 mL. Ele refere ter usado cerca de 300 mL do produto no último ano. O jovem não estava interessado na quantidade maciça de vitaminas contida no produto, mas apenas no efeito local do veículo oleoso; o edema provocado pela injeção simulava um aumento de massa muscular. O produto, no entanto, foi absorvido e causou hipervitaminose. O nível sérico de 25(OH) vitamina D estava claramente elevado em 150 ng/mL (referência de 30 a 60 ng/mL), mas não tanto quanto em outros casos publicados de intoxicação por vitamina D. A maioria dos casos de hipercalcemia por hipervitaminose D se associa a níveis de 25 (OH)D bem maiores do que 200 ng/mL. O PTH estava indetectável, e outras causas de hipercalcemia foram excluídas. Deste modo, conclui-se que a gravidade da hipercalcemia encontrada neste caso foi resultado do efeito sinérgico da intoxicação pelas vitaminas A e D. O paciente foi tratado com soro fisiológico, furosemida e ácido zolendrônico e evoluiu com normalização rápida dos níveis séricos de cálcio e da função renal.

A previously healthy 19 year-old male presented to the hospital with anorexia, nausea, and vomiting. Laboratory studies were significant for hypercalcemia (peak calcium value of 14.8 mg/dL) and acute kidney injury (peak serum creatinine of 2.88 mg/dL). He admitted to using a parenteral formulation of vitamins A, D and E restricted for veterinary use containing 20,000,000 IU of vitamin A; 5,000,000 IU of vitamin D3; and 6,800 IU of vitamin E per 100 mL vial. The patient stated to have used close to 300 mL of the product over the preceding year. Interestingly, the young man was not interested in the massive amounts of vitamins that the product contained; he was only after the local effects of the oily vehicle. The swelling produced by the injection resulted in a silicone-like effect, which gave the impression of bigger muscles. Nevertheless, the product was absorbed and caused hypervitaminosis. The serum level of 25(OH) vitamin D was clearly elevated at 150 ng/mL (reference range from 30 to 60 ng/mL), but in most published cases of vitamin D toxicity, serum levels have been well above 200 ng/mL. His PTH level was undetectable and other potential causes of hypercalcemia were excluded. Therefore, we posit that the severity of the hypercalcemia observed in this case was the result of a synergistic effect of vitamins A and D. The patient was treated with normal saline, furosemide and zolendronic acid, with rapid normalization of calcium levels and renal function.

Distinct patterns of glomerular lesions, including membranoproliferative glomerulonephritis and focal segmental glomerulosclerosis, are associated with infection by Schistosoma mansoni or Schistosoma japonicum. Evidence suggests that immune complex deposition is the main mechanism underlying the different forms of schistosomal glomerulonephritis and that immune complex deposition may be intensified by portal hypertension. The relationship between focal segmental glomerulosclerosis and schistosomiasis remains poorly understood. A clinicopathologic classification of schistosomal glomerulopathies was proposed in 1992 by the African Association of Nephrology. In Brazil, mass treatment with oral medications has led to a decrease in the occurrence of schistosomal glomerulopathy. In a survey of renal biopsies performed in Salvador, Brazil, from 2003-2009, only 24 (4%) patients were identified as positive for S. mansoni infection. Among these patients, only one had the hepatosplenic form of the disease. Focal segmental glomerulosclerosis was found in seven patients and membranoproliferative glomerulonephritis was found in four patients. Although retrospective studies on the prevalence of renal diseases based on kidney biopsies may be influenced by many patient selection biases, a change in the distribution of glomerulopathies associated with nephrotic syndrome was observed along with a decline in the occurrence of severe forms of schistosomiasis.

Hiponatremia é o distúrbio hidroeletrolítico mais comum em pacientes hospitalizados. A presença de hiponatremia está associada a uma série de desfechos desfavoráveis, tais como: necessidade de internamento em unidade de terapia intensiva, hospitalização prolongada e de maior custo, transferência para abrigos e mortalidade. Ainda não está claro se existe relação de causalidade direta ou se a hiponatremia é apenas um marcador de gravidade da doença de base. No entanto, sabe-se que o manejo inadequado de um paciente hiponatrêmico pode causar graves danos neurológicos ou até mesmo a morte. Neste manuscrito, os conceitos básicos sobre a fisiopatologia da hiponatremia serão revisados, seguido de uma abordagem prática sobre sua investigação e tratamento.

Hyponatremia is the most common electrolyte imbalance in hospitalized patients. It is associated with several unfavorable endpoints such as: the need for intensive care, longer hospital stay, higher hospitalization costs, discharge to long-term care facilities, and mortality. It is still not clear if there is a direct causal relationship or if hyponatremia is simply a marker of disease severity. Nevertheless, it is quite clear that improper management of a hyponatremic patient may result in severe neurologic damage or death. This paper addresses the basic pathophysiologic concepts about hyponatremia followed by a practical approach to its diagnosis and management.

Uma fração crescente das atividades clínicas dos nefrologistas é exercida nas unidades de terapia intensiva (UTIs). Ao avaliar pacientes com insuficiência renal aguda no contexto de choque circulatório, que também apresentam anasarca e/ou trocas gasosas ruins, o nefrologista precisa decidir entre duas condutas antagônicas: 1) remover volume através de diálise ou diureticoterapia para melhorar o quadro edematoso; 2) administrar volume para melhorar a hemodinâmica. Para minimizar a chance de decisões incorretas, é imperativo que o nefrologista conheça as ferramentas disponíveis para avaliação hemodinâmica invasiva e de estimativa de adequação da volemia no paciente com doença crítica. Neste artigo, fazemos uma breve revisão da fisiologia da regulação do volume do líquido extracelular e, em seguida, abordamos o diagnóstico de volemia, com base em critérios clínicos e hemodinâmicos.

A growing fraction of the clinical duties of Nephrologists is undertaken inside intensive care units. While assessing patients with acute renal failure in the context of circulatory collapse, which are also edematous and/or with impaired gas exchanges, the Nephrologist must decide between two opposing therapies: 1) remove volume with the aid of dialysis or diuretics to improve the edematous state; 2) volume expand to improve hemodynamics. To minimize the odds of making incorrect choices, the Nephrologist must be familiar with the tools available for determining the adequacy of volume status and for invasive hemodynamic monitoring in the critically ill patient. In this manuscript, we will briefly review the physiology of extra cellular fluid volume regulation and then tackle the issue of volume status assessment, based on clinical and hemodynamic criteria.

INTRODUÇÃO: Pouco se conhece sobre a evolução de pacientes que iniciam DP como única alternativa. OBJETIVOS: Descrever o perfil clínico-demográfico e a ocorrência de peritonite em uma amostra de pacientes convertidos de HD para DP por exaustão de acesso vascular. MÉTODOS: Revisão dos prontuários de todos os pacientes do programa de DP do HGRS. RESULTADOS: Foram estudados 22 pacientes com idade mediana de 47,9 anos, 54,5% de homens, 84,2% de negros ou mulatos, 68,2% procedentes do interior da Bahia. DP foi a modalidade inicial de TRS em apenas quatro pacientes. Os 18 pacientes restantes iniciaram TRS através de HD; neste grupo, predominou o início de HD de forma emergencial e através de cateter duplo-lúmen (CDL). Em uma mediana de 7,7 meses em HD, a maioria dos pacientes (64,7%) usou mais de quatro CDL. Em apenas 7/18 (39%) pacientes, a conversão de HD para DP foi feita por escolha do paciente; na maioria dos casos, 11/18 (61%), o motivo de conversão foi exaustão de acesso vascular para HD. Peritonite foi mais frequente nos pacientes que entraram em HD por exaustão de acesso vascular que no restante do grupo. CONCLUSÕES: O início de TRS de forma emergencial através de HD utilizando CDL pode levar a uma rápida exaustão de acesso vascular, deixando a DP como única alternativa viável. Este modo inadequado de "seleção" de pacientes para DP está associado a maiores chances de ocorrência de peritonite.

INTRODUCTION: Little is known about the prognosis of patients beginnig peritoneal dialysis (PD) as their last alternative. OBJECTIVES: To describe the clinical-demographic profile of patients switching from hemodialysis (HD) to PD, due to exhaustion of the HD vascular access, and the occurrence of peritonitis among them. METHODS: Review of the medical records of all patients in the PD program of the Hospital Roberto Santos in the city of Salvador, state of Bahia, Brazil. RESULTS: The study comprised 22 patients (median age, 47.9 years), 54.5% of whom were men, 84.2%, black or mulattoes, and 68.2% originated from the inner Bahia state. Peritoneal dialysis was the initial modality of renal substitutive therapy (RST) in only four of those patients. The remaining 18 patients began RST through HD, mainly on an emergency basis and by using double-lumen catheter (DLC). In a median of 7.7 months on HD, most patients (64.7%) used four or more DLCs. In only 7/18 (39%) patients, the switch from HD to PD was based on the patient';s choice; in most cases, 11/18 (61%), the reason for switching to PD was exhaustion of HD vascular access. Peritonitis was more frequent in patients switching to PD due to exhaustion of HD vascular access than in the rest of the group. CONCLUSIONS: Initiating RST on an emergency basis through HD and using DLC may lead to a fast exhaustion of vascular access, leaving PD as the only viable option. This inadequate mode of patient "selection" for PD is associated with a higher risk for peritonitis.

A acidose lática é um distúrbio do equilíbrio ácido-base muito frequente em pacientes internados em unidades de terapia intensiva e está associado a um mau prognóstico. Embora exista um acúmulo substancial de evidências de que níveis críticos de acidemia provocam inúmeros efeitos adversos sobre o funcionamento celular, a utilização de bicarbonato de sódio para o tratamento da acidose lática em pacientes gravemente enfermos permanece alvo de controvérsias. Neste artigo, pretendemos: 1) analisar as principais diferenças entre as acidoses hiperclorêmicas e as acidoses orgânicas, com ânion gap (AG) elevado, visando embasar a discussão sobre os fundamentos da terapia com bicarbonato de sódio nas acidoses metabólicas; 2) avaliar os riscos associados à persistência de níveis críticos de acidemia, contrastando-os com os riscos do uso de bicarbonato de sódio; 3) analisar criticamente as evidências da literatura sobre o uso de bicarbonato de sódio no tratamento da acidose lática do paciente crítico, com ênfase em ensaios clínicos randomizados em seres humanos; 4) fornecer um fundamento para a utilização judiciosa de bicarbonato de sódio nesta situação.

Lactic acidosis is an acid-base imbalance frequently found in critically ill patients. It is associated with a poor prognosis. Despite the substantial body of evidence that critical levels of acidemia have several adverse effects on cell function, the use of sodium bicarbonate to treat lactic acidosis in critically ill patients remains highly controversial. This article aimed at: 1) analyzing the main differences between hyperchloremic and organic acidoses, with high anion gap; 2) comparing the risks associated with critical levels of acidemia with those associated with the use of sodium bicarbonate; 3) critically analyzing the literature evidence about the use of sodium bicarbonate for the treatment of lactic acidosis in critically ill patients, with an emphasis on randomized control trials in human beings; and 4) providing a rationale for the judicious use of sodium bicarbonate in that situation.