Carla Valente

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.

Outcomes of cancer and non-cancer patients with acute kidney injury and need of renal replacement therapy admitted to general intensive care units

BACKGROUND Studies on cancer patients with acute kidney injury (AKI) are restricted to specialized intensive care units (ICUs). The aim of this study was to compare the characteristics and outcomes of cancer and non-cancer patients requiring renal replacement therapy (RRT) for AKI in general ICUs. METHODS A prospective cohort study was conducted in 14 ICUs from three tertiary care hospitals. A total of 773 (non-cancer 85%; cancer 15%) consecutive patients were included over a 44-month period. Logistic regression was used to identify factors associated with hospital mortality. RESULTS Continuous RRT was used in 79% patients. The main contributing factors for AKI were sepsis (72%) and ischaemia/shock (66%); AKI was multifactorial in 87% of cancer and in 71% non-cancer patients. Hospital mortality rates were higher in cancer (78%) than in non-cancer patients (68%) (P=0.042). However, in multivariate analyses, older age, medical admission, poor chronic health status, comorbidities, ICU days until the RRT start and number of associated organ dysfunctions were associated with hospital mortality. The diagnosis of cancer was not independently associated with mortality [odds ratio=1.54 (95% confidence interval, 0.88-2.62), P=0.115]. Mortality in cancer patients was mostly dependent on the number of associated organ dysfunctions. Of note, 85% cancer patients recovered renal function at hospital discharge. CONCLUSIONS In general ICUs, one in six patients requiring RRT has cancer. Despite a relatively higher mortality, the presence of cancer was not independently associated with mortality in the present cohort.

SAPS 3 scores at the start of renal replacement therapy predict mortality in critically ill patients with acute kidney injury

Patients can experience acute kidney injury and require renal replacement therapy at any time during their admission to intensive care units. Prognostic scores have been used to characterize and stratify patients by the severity of acute disease, but scores based on findings during the day of admission may not be reliable surrogate markers of the severity of acute illness in this population. The aim of this study was to evaluate the performance of SAPS 3 and MPM(0)-III scores, determined at the start of renal replacement therapy, in 244 patients admitted to 11 units of three hospitals in Rio de Janeiro, Brazil. Continuous renal replacement therapy was used as first indication in 84% of these patients. Discrimination by area under the receiver operating characteristic curve was significantly better for SAPS 3 than for MPM(0)-III, as was the calibration measured by the Hosmer-Lemeshow goodness-of-fit test. Mortality prediction and calibration approached those eventually found when a customized equation of SAPS 3 for Central and South America was used. After adjusting for other relevant covariates in multivariate analyses, both higher prognostic scores and length of stay in the unit prior to the start of renal replacement therapy were the main predictive factors for hospital mortality. Our study shows that a customized SAPS 3 model was accurate in predicting mortality and seems a promising algorithm to characterize and stratify patients in clinical studies.

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 (Δ-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 Δ-SOFA (p=0.016) were higher in non-survivors. However, neither A-SOFA nor Δ-SOFA discriminated survivors from non-survivors on an individual basis. Adjusting for other covariates (including SOFA on D1), A-SOFA and Δ-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

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.

The evaluation of sequential platelet counts has prognostic value for acute kidney injury patients requiring dialysis in the intensive care setting

OBJECTIVE: To evaluate the prognostic value of platelet counts in acute kidney injury patients requiring renal replacement therapy. METHODS: This prospective cohort study was performed in three tertiary-care hospitals. Platelet counts were obtained upon admission to the intensive care unit and during the first week of renal replacement therapy on days 1, 3, 5 and 7. The outcome of interest was the hospital mortality rate. With the aim of minimizing individual variation, we analyzed the relative platelet counts on days 3, 5, 7 and at the point of the largest variation during the first week of renal replacement therapy. Logistic regression analysis was used to test the prognostic value of the platelet counts. RESULTS: The study included 274 patients. The hospital mortality rate was 62%. The survivors had significantly higher platelet counts upon admission to the intensive care unit compared to the non-survivors [175.5×103/mm3 (108.5–259×103/mm3) vs. 148×103/mm3 (80−141×103/mm3)] and during the first week of renal replacement therapy. The relative platelet count reductions were significantly associated with a higher hospital mortality rate compared with the platelet count increases (70% vs. 44% at the nadir, respectively). A relative platelet count reduction >60% was significantly associated with a worse outcome (mortality rate = 82.6%). Relative platelet count variations and the percentage of reduction were independent risk factors of hospital mortality during the first week of renal replacement therapy. CONCLUSION: Platelet counts upon admission to the intensive care unit and at the beginning of renal replacement therapy as well as sequential platelet count evaluation have prognostic value in acute kidney injury patients requiring renal replacement therapy.

Predialysis hypernatremia is a prognostic marker in acute kidney injury in need of renal replacement therapy

BACKGROUND AND OBJECTIVES The present study aimed to evaluate the prognostic impact of predialysis dysnatremia in patients with acute kidney injury requiring renal replacement therapy (RRT). DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS A secondary analysis of a prospective multicenter cohort study was performed. Serum sodium (Na) concentrations were categorized immediately before the first RRT as normonatremia (135≤Na ≤145mEq/L), hyponatremia (mild [130≤Na ≤134mEq/L] or severe [Na ≤129mEq/L]), and hypernatremia (mild [146≤Na ≤155mEq/L] or severe [Na ≥156mEq/L]). Multivariable logistic regression was used to estimate the impact of sodium levels categories on hospital mortality. RESULTS Dysnatremia occurred in 47.3% of 772 included patients. Hypernatremia was more frequent than hyponatremia (33.7% vs 13.6%, P=.001). Intensive care unit (ICU) and hospital mortality rates were 64.6% and 69%, respectively. Hospital mortality was higher in severe hypernatremia (89.1% [95% confidence interval {CI}, 78.7%-95.8%] vs 64.6% [CI, 59.8%-69.2%], P<.001, in normonatremia). Older patients, clinical admission, number of comorbidities, length of ICU stay before the beginning of RRT, and the number of organ dysfunctions were associated with higher hospital mortality. In multivariate analysis, severe hypernatremia (odds ratio, 2.87; 95% CI, 1.2-6.9), poor chronic heath status, severity of illness, sepsis, and lactate were independently associated with outcome. CONCLUSION Almost 50% of patients with acute kidney injury in need of RRT in the ICU had mild or severe dysnatremia before dialysis initiation. Hypernatremia was the main sodium disturbance and independently associated with poor outcome in the study population.