Outcomes of critically ill patients with acute kidney injury and end-stage renal disease requiring renal replacement therapy: a case-control study.

BACKGROUND: This study aimed to evaluate and compare the characteristics and outcomes of patients with end-stage renal disease (ESRD) with those of matched controls of patients with acute kidney injury (AKI) requiring renal replacement therapy. METHODS: A case-control study was performed at the intensive care units (ICU) of three tertiary-care hospitals between December 2004 and September 2007. Patients were admitted with life-threatening complications and were matched for age and for severity of illness and organ dysfunctions. Conditional logistic regression was used to identify factors associated with hospital mortality. RESULTS: A total of 54 patients with ESRD and 54 patients with AKI were eligible for the study and were well matched. In general, clinical characteristics were similar. Nonetheless, comorbidities were more frequent in patients with ESRD, and patients with AKI more frequently required mechanical ventilation. ICU (43% versus 20%, P = 0.023) and hospital (50% versus 24%, P = 0.010) mortality rates were higher in patients with AKI. In addition, patients with AKI experienced longer ICU and hospitals stays. The SAPS II score had a regular ability in discriminating survivors and non-survivors, and tended to underestimate mortality in patients with AKI and overestimate in patients with ESRD. When all patients were evaluated, older age [OR = 1.05 (95% CI, 1.01-1.09)], poor chronic health status [OR = 3.90(1.19-12.82)] and number of associated organ failures [OR = 4.44(1.97-10.00)] were the main independent predictors of mortality. After adjusting for those covariates, ESRD was still associated with a lower probability of death [OR = 0.17 (0.06-0.050)]. CONCLUSIONS: ESRD patients with life-threatening complications had significantly better outcome than AKI patients.

Effects of early changes in organ dysfunctions on the outcomes of critically ill patients in need of renal replacement therapy.

INTRODUCTION: Acute kidney injury usually develops in critically ill patients in the context of multiple organ dysfunctions. OBJECTIVE: To evaluate the effect of changes in associated organ dysfunctions over the first three days of renal replacement therapy on the outcomes of patients with acute kidney injury. METHODS: Over a 19-month period, we evaluated 260 patients admitted to the intensive care units of three tertiary-care hospitals who required renal replacement therapy for > 48 h. Organ dysfunctions were evaluated by SOFA score (excluding renal points) on the first (D1) and third (D3) days of renal replacement therapy. Absolute (A-SOFA) and relative (Delta-SOFA) changes in SOFA scores were also calculated. RESULTS: Hospital mortality rate was 75%. Organ dysfunctions worsened (A-SOFA>0) in 53%, remained unchanged (A-SOFA=0) in 17% and improved (A-SOFA<0) in 30% of patients; and mortality was lower in the last group (80% vs. 84% vs. 61%, p=0.003). SOFA on D1 (p<0.001), SOFA on D3 (p<0.001), A-SOFA (p=0.019) and Delta-SOFA (p=0.016) were higher in non-survivors. However, neither A-SOFA nor Delta-SOFA discriminated survivors from non-survivors on an individual basis. Adjusting for other covariates (including SOFA on D1), A-SOFA and Delta-SOFA were associated with increased mortality, and patients in whom SOFA scores worsened or remained unchanged had poorer outcomes. CONCLUSIONS: In addition to baseline values, early changes in SOFA score after the start of renal replacement therapy were associated with hospital mortality. However, no prognostic score should be used as the only parameter to predict individual outcomes.

Desempenho de seis modelos de predição prognóstica em pacientes críticos que receberam suporte renal extracorpóreo / Performance of six prognostic scores in critically ILL patients receiving renal replacement therapy

JUSTIFICATIVA E OBJETIVOS: Não existe consenso sobre qual modelo prognóstico deva ser utilizado em pacientes com disfunção renal aguda (DRA). O objetivo deste estudo foi avaliar o desempenho de seis escores de prognóstico em pacientes que necessitaram de suporte renal. MÉTODO: Coorte prospectiva de pacientes internados nas unidades de terapia intensiva (UTI) de três hospitais terciários que necessitaram de suporte renal por DRA durante 32 meses. Foram excluídos os pacientes crônicos em programa de diálise ou com < 24h de internação na UTI. Os dados das primeiras 24h de UTI foram utilizados no cálculo do SAPS II e do APACHE II, e os dados das primeiras 24h de suporte renal foram utilizados no cálculo dos escores LOD, ODIN, Liaño e Mehta. A discriminação foi avaliada através da área sobre a curva ROC (AUROC) e a calibração através do teste do goodness-of-fit de Hosmer-Lemeshow. A letalidade hospitalar foi o desfecho de interesse. RESULTADOS: Quatrocentos e sesseta e sete pacientes foram incluídos e a letalidade hospitalar foi 75 por cento. Os valores dos escores SAPS II, APACHE II e LOD foram 48,5 ± 11,2, 27,4 ± 6,3, 7 (5-8) pontos, respectivamente. A calibração foi adequada para todos os escores, com exceção do Mehta (p = 0,001). Entretanto, a discriminação foi ruim para todos os modelos, com AUROC variando entre 0,60 para o ODIN e 0,72 para o SAPS II e Mehta. Com exceção do Mehta, todos os modelos subestimaram a letalidade. CONCLUSÕES: Todos os seis modelos estudados foram inadequados na predição prognóstica de pacientes graves com DRA e necessidade de suporte renal.

BACKGROUND AND OBJECTIVES: There is no consensus about prognostic scores for use in patients with acute kidney injury (AKI). The aim of this study was to evaluate the performance of six prognostic scores in predicting hospital mortality in patients with AKI and need for renal replacement therapy (RRT). METHODS: Prospective cohort of patients admitted to the intensive care units (ICU) of three tertiary care hospitals that required RRT for AKI over a 32-month period. Patients with end-stage renal disease and those with ICU stay < 24h were excluded. Data from the first 24h of ICU admission were used to calculate SAPS II and APACHE II scores, and data from the first 24h of RRT were used in the calculation of LOD, ODIN, Liaño and Mehta scores. Discrimination was evaluated using the area under ROC curve (AUROC) and calibration using the Hosmer-Lemeshow goodness-of-fit test. The hospital mortality was the end-point of interest. RESULTS: 467 patients were evaluated. Hospital mortality rate was 75 percent. Mean SAPS II and APACHE II scores were 48.5 ±11.2 and 27.4 ± 6.3 points, and median LOD score was 7 (5-8) points. Except for Mehta score (p = 0.001), calibration was appropriate in all models. However, discrimination was uniformly unsatisfactory; AUROC ranged from 0.60 for ODIN to 0.72 for SAPS II and Mehta scores. In addition, except for Mehta, all models tended to underestimate hospital mortality. CONCLUSIONS: Organ dysfunction, general and renal-specific severity-of-illness scores were inaccurate in predicting outcome in ICU patients in need for RRT.

Performance of six prognostic scores in critically ILL patients receiving renal replacement therapy. / Desempenho de seis modelos de predição prognóstica em pacientes críticos que receberam suporte renal extracorpóreo.

BACKGROUND AND OBJECTIVES: There is no consensus about prognostic scores for use in patients with acute kidney injury (AKI). The aim of this study was to evaluate the performance of six prognostic scores in predicting hospital mortality in patients with AKI and need for renal replacement therapy (RRT). METHODS: Prospective cohort of patients admitted to the intensive care units (ICU) of three tertiary care hospitals that required RRT for AKI over a 32-month period. Patients with end-stage renal disease and those with ICU stay < 24h were excluded. Data from the first 24h of ICU admission were used to calculate SAPS II and APACHE II scores, and data from the first 24h of RRT were used in the calculation of LOD, ODIN, Liaño and Mehta scores. Discrimination was evaluated using the area under ROC curve (AUROC) and calibration using the Hosmer-Lemeshow goodness-of-fit test. The hospital mortality was the end-point of interest. RESULTS: 467 patients were evaluated. Hospital mortality rate was 75%. Mean SAPS II and APACHE II scores were 48.5 ±11.2 and 27.4 ± 6.3 points, and median LOD score was 7 (5-8) points. Except for Mehta score (p = 0.001), calibration was appropriate in all models. However, discrimination was uniformly unsatisfactory; AUROC ranged from 0.60 for ODIN to 0.72 for SAPS II and Mehta scores. In addition, except for Mehta, all models tended to underestimate hospital mortality. CONCLUSIONS: Organ dysfunction, general and renal-specific severity-of-illness scores were inaccurate in predicting outcome in ICU patients in need for RRT.

Effects of early changes in organ dysfunctions on the outcomes of critically ill patients in need of renal replacement therapy

INTRODUCTION: Acute kidney injury usually develops in critically ill patients in the context of multiple organ dysfunctions. OBJECTIVE: To evaluate the effect of changes in associated organ dysfunctions over the first three days of renal replacement therapy on the outcomes of patients with acute kidney injury. METHODS: Over a 19-month period, we evaluated 260 patients admitted to the intensive care units of three tertiary-care hospitals who required renal replacement therapy for > 48 h. Organ dysfunctions were evaluated by SOFA score (excluding renal points) on the first (D1) and third (D3) days of renal replacement therapy. Absolute (A-SOFA) and relative (D-SOFA) changes in SOFA scores were also calculated. RESULTS: Hospital mortality rate was 75 percent. Organ dysfunctions worsened (A-SOFA>0) in 53 percent, remained unchanged (A-SOFA=0) in 17 percent and improved (A-SOFA<0) in 30 percent of patients; and mortality was lower in the last group (80 percent vs. 84 percent vs. 61 percent, p=0.003). SOFA on D1 (p<0.001), SOFA on D3 (p<0.001), A-SOFA (p=0.019) and D-SOFA (p=0.016) were higher in non-survivors. However, neither A-SOFA nor D-SOFA discriminated survivors from non-survivors on an individual basis. Adjusting for other covariates (including SOFA on D1), A-SOFA and D-SOFA were associated with increased mortality, and patients in whom SOFA scores worsened or remained unchanged had poorer outcomes. CONCLUSIONS: In addition to baseline values, early changes in SOFA score after the start of renal replacement therapy were associated with hospital mortality. However, no prognostic score should be used as the only parameter to predict individual outcomes.

RIFLE classification in patients with acute kidney injury in need of renal replacement therapy.

OBJECTIVES: To evaluate the association of RIFLE classification with the outcomes of critically ill patients with acute kidney injury (AKI) who require renal replacement therapy (RRT). DESIGN AND SETTING: Prospective cohort study in the medical-surgical ICUs at three tertiary hospitals. PATIENTS: 214 patients over 1 year (mean age 71.4+/-15.8 years). Continuous RRT was used in 179 (84%); patients were classified as risk (25%), injury (27%), or failure (48%). Overall mortality was 76%. MEASUREMENTS AND RESULTS: There were no significant differences according to RIFLE classification (risk 72%, injury 79%, failure 76%). Variables selected in multivariate analysis were: older age (OR 1.03, 95% CI 1.01-1.06), presence of comorbidity (3.15, 1.10-9.02), poor chronic health status (6.51, 1.95-21.71), number of associated organ dysfunctions (patients with one or two organ dysfunctions 5.93, 2.03-17.33; patients with three or more organ dysfunctions 26.76, 6.28-114.11), and start of RRT after the first day of ICU (2.46, 1.09-5.53). RIFLE classification was forced into the model and was not selected. However, a subgroup analysis of 150 patients who received mechanical ventilation and vasopressors found failure to be associated with increased mortality (3.58, 1.08-11.80). CONCLUSIONS: Older age, number of organ dysfunctions, presence of comorbidities, and reduced functional capacity were the main prognostic factors. Patients who required RRT after the first day of ICU had a worse outcome. The RIFLE classification did not discriminate the prognosis in patients with AKI in need for RRT.