Renal failure in the ICU: comparison of the impact of acute renal failure and end-stage renal disease on ICU outcomes

BACKGROUND: Acute renal failure (ARF) is associated with a persistent high mortality in critically ill patients in intensive care units (ICUs). Most studies to date have focused on patients with established, intrinsic ARF or relatively severe ARF due to multiple factors. None have examined outcomes of dialysis-dependent chronic renal failure [end-stage renal disease (ESRD)] patients in the ICU. We examined the incidence and outcomes of ARF in the ICU using a standard definition and compared these to outcomes of ICU patients with either ESRD or no renal failure. We sought to determine the impact of renal dysfunction and/or loss of organ function on outcome. METHODS: We prospectively scored 1530 admissions to eight ICUs over a 10-month period for illness severity at ICU admission using the Acute Physiological and Chronic Health Evaluation (APACHE III) evaluation tool. Patients were defined as having ARF based on the definition of Hou et al (Am J Med 74:243-248,1983) designed to detect significant measurable declines in renal function based on serum creatinine. ESRD patients were identified as being chronically dialysis-dependent prior to ICU admission and the remainder had no renal failure. Clinical characteristics at ICU admission and ICU and hospital outcomes were compared between the three groups. RESULTS: We identified 254 cases of ARF, 57 cases of ESRD and 1219 cases of no renal failure for an incidence of ARF of 17%. Roughly half the ARF patients had ARF at ICU admission and the remainder developed ARF during their ICU stay. Only 11% of ARF patients required dialysis support. ARF patients had significantly higher acute illness severity scores than those with no renal failure, whereas patients with ESRD had intermediate severity scores. ICU mortality was 23% for patients with ARF, 11% for those with ESRD, and 5% for those with no renal failure. There was no difference in outcome between patients who had ARF at ICU admission and those who developed ARF in the ICU. Patients with ARF severe enough to require dialysis had a mortality of 57%. APACHE III predicted outcome very well in patients with no renal failure and patients with ARF at the time of scoring but underpredicted mortality in those who developed ARF after ICU admission and overestimated mortality in patients with ESRD. CONCLUSIONS: ARF is common in ICU patients and has a persistent negative impact on outcomes, although the majority of ARF is not severe enough to require dialysis support. The mortality of patients with ARF from all causes is almost exactly similar to that noted using the same criteria two decades ago. More profound ARF requiring dialysis continues to have an even greater mortality. Nevertheless, acute declines in renal function are associated with a mortality that is not well explained simply by loss of organ function. The majority of ARF patients who did not require dialysis still had a considerably higher mortality than the ESRD patients, all of whom required dialysis; while ARF patients who did require dialysis had a much higher morality than ESRD patients. APACHE III performs well and captures the mortality of patients with ARF at the time of scoring. Development of ARF after scoring has a profound effect on standardized mortality. We were unable to identify a unique mortality associated with ARF, but the presence of measurable renal insufficiency continues to be a sensitive marker for poor outcome.     

Acute Renal Failure During Eclampsia: Incidence Risks Factors and Outcome in Intensive Care Unit

Objective: To assess the incidence, risk factors and the outcome of acute renal failure (ARF) associated with eclampsia in intensive care unit (ICU). Design: Prospective and analytic study. Setting: A surgical ICU in a university hospital. Patients: 178 consecutive women with eclampsia admitted to an intensive care unit during seven years. ARF was defined by a serum creatinine concentration > 140 µmol/L. Results: The incidence of ARF was 25.8%. In univariate analysis the severity of patient illness, the complications associated with eclampsia (disseminated intravascular coagulation, Hellp syndrome, neurologic complications, abruptio placenta, aspiration pneumonia, delivery hemorrhage) were significantly associated with ARF. In a logistic regression model, risk factors for ARF included organ system failure (OSF) odds ratio (OR) = 1.81 confidence interval (CI) [1.08–3.05], bilirubin > 12 µmol/L OR = 4.42 CI [1.54–12.68], uric acid > 5.9 g/dL OR = 16.5 CI [3.09–87.94], abruptio placenta OR = 0.2 7 CI [0.08–0.99], and oliguria OR = 0.10 CI [0.03–0.44]. In contrast, severity of blood pressure or proteinuria on dipstick were not associated with ARF. However, in this series, 15 women required dialysis in the short term and one required long‐term dialysis. ARF associated with eclampsia was significantly associated with mortality (32.6% versus 9.1% p = 0.0001). Conclusion: ARF with eclampsia is a frequent situation that required intensive management when risks factors were present. The need for dialysis was a rare condition.     

Risk factors for acute renal failure requiring dialysis after surgery for congenital heart disease in children

BACKGROUND: Limited data exist on the risk factors for acute renal failure (ARF) following cardiac surgery in children with congenital heart disease. This cohort study was conducted to examine this subject, as well as changes in the incidence of ARF from 1993 to 2002, the in-hospital mortality and the time spent in the intensive care unit (ICU). METHODS: One thousand, one hundred and twenty-eight children, operated on for congenital heart disease between 1993 and 2002, were identified from our prospectively collected ICU database to obtain data on potential risk factors. RESULTS: A total of 130 children (11.5%) developed ARF after surgery. A young age [> or =1.0 vs. <0.1 year; odds ratio (OR), 0.23; 95% confidence interval (CI), 0.12-0.46], high Risk Adjusted Classification of Congenital Heart Surgery (RACHS-1) score (OR, 2.72; 95% CI, 1.66-4.45) and cardiopulmonary bypass (CPB) (<90 min vs. none; OR, 2.68; 95% CI, 1.03-6.96; > or =90 min vs. none; OR, 12.94; 95% CI, 5.46-30.67) were independent risk factors for ARF. The risk of ARF decreased during the study period. Children with ARF spent a significantly longer time in the ICU (2-7 days vs. <2 days, P = 0.002; > or =7 days vs. <2 days, P < 0.001) compared with non-ARF patients, and showed increased in-hospital mortality (20% vs. 5%, P < 0.001). CONCLUSION: A young age, high RACHS-1 score and CPB were independent risk factors for ARF after surgical procedures for congenital heart disease in children. The risk of ARF decreased during the study period. Children with severe ARF spent a longer time in the ICU, and the mortality in ARF patients was higher than that in non-ARF patients.     

Acute renal failure during eclampsia: incidence risks factors and outcome in intensive care unit

OBJECTIVE: To assess the incidence, risk factors and the outcome of acute renal failure (ARF) associated with eclampsia in intensive care unit (ICU). DESIGN: Prospective and analytic study. SETTING: A surgical ICU in a university hospital. PATIENTS: 178 consecutive women with eclampsia admitted to an intensive care unit during seven years. ARF was defined by a serum creatinine concentration >140 micromol/L. RESULTS: The incidence of ARF was 25.8%. In univariate analysis the severity of patient illness, the complications associated with eclampsia (disseminated intravascular coagulation, Hellp syndrome, neurologic complications, abruptio placenta, aspiration pneumonia, delivery hemorrhage) were significantly associated with ARF. In a logistic regression model, risk factors for ARF included organ system failure (OSF) odds ratio (OR)=1.81 confidence interval (CI) [1.08-3.05], bilirubin >12 micromol/L OR=4.42 CI [1.54-12.68], uric acid >5.9 g/dL OR=16.5 CI [3.09-87.94], abruptio placenta OR=0.2 7 CI [0.08-0.99], and oliguria OR=0.10 CI [0.03-0.44]. In contrast, severity of blood pressure or proteinuria on dipstick were not associated with ARF. However, in this series, 15 women required dialysis in the short term and one required long-term dialysis. ARF associated with eclampsia was significantly associated with mortality (32.6% versus 9.1% p=0.0001). CONCLUSION: ARF with eclampsia is a frequent situation that required intensive management when risks factors were present. The need for dialysis was a rare condition.     

Prognosis of patients with acute renal failure requiring dialysis: results of a multicenter study

Despite several decades of clinical experience, the mortality rate for patients with acute renal failure (ARF) requiring dialysis remains high, and the evaluation of the patients prognosis has been difficult. To date, the Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring system has been used more frequently for prediction in studies of ARF than any other scoring system, but has not been prospectively validated in controlled multicenter studies of this entity. In a multicenter, prospective, controlled trial evaluating the use of biocompatible hemodialysis membranes (BCMs) in patients with ARF, we evaluated the extent to which the APACHE II scoring system, based on the physiological variables in the 24 hours before the onset of dialysis and the presence or absence of oliguria, is predictive of outcome. Analysis of survival and recovery of renal function for the 153 patients treated in this study show that APACHE II scores are predictive both of survival and recovery of renal function, whether analyzed separately by type of dialysis membrane used (BCM or bioincompatible [BICM]) or for both groups combined (all P < 0.01). There was no evidence of a significant center effect or interaction of APACHE II score with dialysis membrane in our study. After adjusting for the APACHE II score, there was a positive effect of the BCM on both probability of survival (P < 0.05) and recovery of renal function (P < 0.01). In patients dialyzed with BCMs, oliguria at onset of dialysis had an adverse effect on both survival and recovery of renal function (both P < 0.01). Receiver operator curves (ROCs) using APACHE II score and the use of BCMs in nonoliguric patients yielded a statistically significant improvement versus the use of APACHE II score alone in the area under the curve (AUC) for survival (0.747 to 0.801; P < 0.05) and recovery of renal function (0.712 to 0.775; P < 0.05). We conclude that the use of the APACHE II score determined at the time of initiation of dialysis for patients with ARF is a statistically significant predictor of patient survival and recovery of renal function. The use of the APACHE II score measured at the time of dialysis initiation, especially when modified by the presence or absence of oliguria, should help in predicting outcome when evaluating interventions for patients with ARF.     

Acute renal failure in intensive care unit: which factors predict future dialysis dependency?

Management of acute renal failure (ARF) in an intensive care unit (ICU) is difficult. The aim of this study was to identify prognostic factors determining ARF outcome in the ICU in terms of dialysis dependency or independency. We included 35 patients who turned out to be dialysis dependent (DD) and 11 patients who turned out to be dialysis independent (DI) after ARF in the ICU, which necessitated renal replacement therapy. In the post-ARF period, acetylsalicylic acid was protective against dialysis dependency (p < 0.05, odds ratio [OR] = 0.078) and dopamine increased the likelihood of dialysis dependency (p = 0.016, OR = 10.6). Multiorgan dysfunction (p = 0.001, OR = 13.6), especially cardiac (p = 0.009) and hepatic failure (p < 0.0001) were determined to increase risk of dialysis dependency. Mean systolic blood pressures during the first 24 hours (p = 0.023) and 24-48 hours (p = or < 0.0001), mean diastolic blood pressures during first the 24-48 hours (p = 0.03) and 48-72 hours of ARF in ICU (p = 0.023) and at discharge (p = 0.03) were significantly lower in the DD group than in the DI group. Mean thrombocyte counts at hospitalization (p = 0.034), during the first 24 hours (p = 0.019) and 24-48 hours of ARF in ICU (p = 0.038) were lower in the DD than DI group. This study demonstrates the very early prognostic factors influencing ARF outcome in terms of dialysis dependency. Early thrombocyte count and systolic blood pressure and follow-up diastolic blood pressure were prognostic factors for ARF outcome. Acetylsalicylic acid seemed to improve renal outcome, whereas dopamine seemed to worsen the disease process.     

Prediction of acute renal failure by "bedside formula" in medical and surgical intensive care patients

BACKGROUND: Prediction of which intensive care unit (ICU) patients are likely to develop acute renal failure (ARF) would be useful. However, scoring systems such as APACHE have been disappointing in this regard. We previously developed a bedside formula to predict ARF using only 3 parameters: serum albumin, urine osmolality, and presence of sepsis. METHODS: We prospectively evaluated 115 consecutive medical ICU (MICU) patients, comparing the bedside formula to APACHE II AND APACHE III as predictors of ARF or death and looking at nutritional parameters such as iron binding capacity, triceps skin fold, mid-arm circumference, and total lymphocyte count. We then evaluated 123 additional consecutive MICU and 98 consecutive surgical ICU (SICU) patients, comparing the bedside formula to APACHE II. RESULTS: The bedside formula was consistently more accurate than APACHE II in predicting ARF or in-hospital death in MICU patients. However, in SICU neither formula predicted ARF, and APACHE II predicted in-hospital death slightly better. No nutritional parameter other than albumin correlated with ARF. CONCLUSION: The bedside formula appears superior to APACHE II in predicting ARF or death in MICU but not SICU. This suggests that these two ICU populations are different.     

Accuracy of shock index versus ABC score to predict need for massive transfusion in trauma patients

BackgroundVarious scoring systems have been developed to predict need for massive transfusion in traumatically injured patients. Assessments of Blood Consumption (ABC) score and Shock Index (SI) have been shown to be reliable predictors for Massive Transfusion Protocol (MTP) activation. However, no study has directly compared these two scoring systems to determine which is a better predictor for MTP activation. The primary objective was to determine whether ABC or SI better predicted the need for MTP in adult trauma patients with severe hemorrhage.MethodsThis was a retrospective cohort study which included all injured patients who were trauma activations between January 1, 2009 and December 31, 2013 at an urban Level I trauma center. Patients <18 years old or with traumatic brain injury (TBI) were excluded. ABC and SI were calculated for each patient. MTP was defined as need for >10 units PRBC transfusion within 24 h of emergency department arrival. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) were used to evaluate scoring systems’ ability to predict effective MTP utilization.ResultsA total of 645 patients had complete data for analysis. Shock Index ≥1 had sensitivity of 67.7% (95% CI 49.5%–82.6%) and specificity of 81.3% (95% CI 78.0%–84.3%) for predicting MTP, and ABC score ≥2 had sensitivity of 47.0% (95% CI 29.8%–64.9%) and specificity of 89.8% (95% CI 87.2%–92.1%). AUROC analyses showed SI to be the strongest predictor followed by ABC score with AUROC values of 0.83 and 0.74, respectively. SI had a significantly greater sensitivity (P = 0.035), but a significantly weaker specificity (P < 0.001) compared to ABC score.ConclusionABC score and Shock Index can both be used to predict need for massive transfusion in trauma patients, however SI is more sensitive and requires less technical skill than ABC score.     

Pattern of acute renal failure in a tertiary hospital in the United Arab Emirates

Acute renal failure (ARF) is a challenging problem in nephrology. To evaluate the pattern, management and outcome of ARF in our tertiary hospital, we analyzed the data of all 81 patients admitted with or developing ARF in hospital between January 2002 and June 2003. The 45 men and 36 women of mean age 56.2 +/- 21 (range 13 to 91) years were managed either on the ward (n = 48; 59%) and or in the ICU (n = 33; 41%) 10% were direct admissions to the nephrology service with ARF, and 90% developed ARF in hospital. Thirty percent were referred by oncology services and 15% by general medicine. Sepsis was the cause of ARF in 36 (44%) patients, followed by drug nephrotoxicity in 11 (14%), and obstructive uropathy in 9 (11%). Comorbid conditions were hypertension in 28 (35%); diabetes in 27 (33%); chronic renal failure, 19 (23%); ischemic heart disease 19 (23%); and liver disease 12 (15%). The most common predisposing factor was hypotension in 42 (52%), dehydration in 32 (40%), and drug nephrotoxicity in 20 (25%). Sixty patients (74%) were managed conservatively, and 21 (26%) required renal replacement therapy. The length of hospital stay was 29.5 +/- 38.4 (range 2 to 279) days. Patient survival for those managed on the ward was 71% compared to 33% for ICU patients (P <.00001). Renal survival was 83% for ward patients, compared to 48% for those in the ICU (P <.001). This study showed that majority of ARF developed in-hospital with oncology patients constituting the greatest proportion. Sepsis was the leading cause of ARF and hypotension, the main predisposing factor. Patients treated in the ICU showed a worse prognosis for both patient and renal survival.     

Hyperglycaemia and renal ischaemia-reperfusion injury.

Introduction Hyperglycaemia is most probably a contributing factor in thedevelopment of ischaemic acute renal failure (ARF) in many patients.Both clinical and experimental data suggest that hyperglycaemiaincreases the risk of ARF [1–3]. Hyperglycaemia also worsensthe outcome in renal transplantation [4,5]. Conversely, ischaemia–reperfusion(I/R) combined with hyperglycaemia could also be important inthe development of diabetic nephropathy. Studies in our laboratoryshow that a brief renal ischaemia results in a progressive injuryleading to end-stage renal failure in diabetic animals [6,7].The mechanisms behind this increased sensitivity to renal I/Rduring hyperglycaemia are still poorly understood. Experimental findings An increased susceptibility to renal I/R injury in diabeticrats has been shown in several studies [1,3,6–9]. Furthermore,non-diabetic rats and dogs are more vulnerable     

Effects of hydroxyethyl starch administration on renal function in critically ill patients

BACKGROUND: The influence of hydroxyethyl starch (HES) solutions on renalfunction is controversial. We investigated the effect of HESadministration on renal function in critically ill patientsenrolled in a large multicentre observational European study. METHODS: All adult patients admitted to the 198 participating intensivecare units (ICUs) during a 15-day period were enrolled. Prospectivelycollected data included daily fluid administration, urine output,sequential organ failure assessment (SOFA) score, serum creatininelevels, and the need for renal replacement therapy (RRT) duringthe ICU stay. RESULTS: Of 3147 patients, 1075 (34%) received HES. Patients who receivedHES were older [mean (SD): 62 (SD 17) vs 60 (18) years,P = 0.022], more likely to be surgical admissions, had a higherincidence of haematological malignancy and heart failure, higherSAPS II [40.0 (17.0) vs 34.7 (16.9), P < 0.001] and SOFA[6.2 (3.7) vs 5.0 (3.9), P < 0.001] scores, and less likelyto be receiving RRT (2 vs 4%, P < 0.001) than those who didnot receive HES. The renal SOFA score increased significantlyover the ICU stay independent of the type of fluid administered.Although more patients who received HES needed RRT than non-HESpatients (11 vs 9%, P = 0.006), HES administration was not associatedwith an increased risk for subsequent RRT in a multivariableanalysis [odds ratio (OR): 0.417, 95% confidence interval (CI):0.05–3.27, P = 0.406]. Sepsis (OR: 2.03, 95% CI: 1.37–3.02,P < 0.001), cardiovascular failure (OR: 6.88, 95% CI: 4.49–10.56,P < 0.001), haematological cancer (OR: 2.83, 95% CI: 1.28–6.25,P = 0.01), and baseline renal SOFA scores > 1 (P < 0.01for renal SOFA 2, 3, and 4 with renal SOFA = 0 as a reference)were all associated with a higher need for RRT. CONCLUSIONS: In this observational study, haematological cancer, the presenceof sepsis, cardiovascular failure, and baseline renal functionas assessed by the SOFA score were independent risk factorsfor the subsequent need for RRT in the ICU. The administrationof HES had no influence on renal function or the need for RRTin the ICU.     

Effect of Fenoldopam Mesylate in Critically Ill Patients at Risk for Acute Renal Failure is Dose Dependent

Background: Acute renal failure (ARF) is common and difficult to prevent, especially in intensive care unit (ICU) patients with cancer. Therapeutic trials with various agents have generally been ineffective in preventing ARF. We describe the effects of two different doses of the dopamine DA-1 receptor agonist fenoldopam mesylate on renal function in a series of critically ill cancer patients at risk of developing ARF. Methods: We performed a retrospective chart review of 100 consecutive patients who received fenoldopam mesylate for at least 72 h in the medical and surgical ICUs of The University of Texas M. D. Anderson Cancer Center who were at risk of developing ARF. Eighteen patients received low-dose fenoldopam mesylate (≤ 0.05 µg/kg/min). The remaining 82 patients received high-dose fenoldopam mesylate (0.07–0.1 µg/kg/min). Data were collected relating to drug dosage, patient demographics, severity of illness, and indices of renal function. Results: Patients were moderately ill, with a mean APACHE II score of 18 ± 6 at initiation of fenoldopam infusion. Eighty-five percent of patients had at least two risk factors for the development of ARF, and 20% had four. For the group overall, the incidence of ARF was 13%, and the hospital mortality rate was 37%. When compared with the low-dose group, patients who received high-dose fenoldopam had a significantly shorter ICU length of stay despite a significantly higher APACHE II score (p = 0.01). The high-dose group also had a highly significant decrease in serum creatinine levels at 72 h (p = 0.005). Conclusions: These data support the hypothesis that fenoldopam mesylate may provide a degree of dose-dependent renal protection in cancer patients with early acute renal failure.     

Comparison of continuous and intermittent renal replacement therapy for acute renal failure.

BACKGROUND: Mortality rates of critically ill patients with acute renal failure (ARF) requiring renal replacement therapy (RRT) are high. Intermittent and continuous RRT are available for these patients on the intensive care units (ICUs). It is unknown which technique is superior with respect to patient outcome. METHODS: We randomized 125 patients to treatment with either continuous venovenous haemodiafiltration (CVVHDF) or intermittent haemodialysis (IHD) from a total of 191 patients with ARF in a tertiary-care university hospital ICU. The primary end-point was ICU and in-hospital mortality, while recovery of renal function and hospital length of stay were secondary end-points. RESULTS: During 30 months, no patient escaped randomization for medical reasons. Sixty-six patients were not randomized for non-medical reasons. Of the 125 randomized patients, 70 were treated with CVVHDF and 55 with IHD. The two groups were comparable at the start of RRT with respect to age (62+/-15 vs 62+/-15 years, CVVHDF vs IHD), gender (66 vs 73% male sex), number of failed organ systems (2.4+/-1.5 vs 2.5+/-1.6), Simplified Acute Physiology Scores (57+/-17 vs 58+/-23), septicaemia (43 vs 51%), shock (59 vs 58%) or previous surgery (53 vs 45%). Mortality rates in the hospital (47 vs 51%, CVVHDF vs IHD, P = 0.72) or in the ICU (34 vs 38%, P = 0.71) were independent of the technique of RRT applied. Hospital length of stay in the survivors was comparable in patients on CVVHDF [median (range) 20 (6-71) days, n = 36] and in those on IHD [30 (2-89) days, n = 27, P = 0.25]. The duration of RRT required was the same in both groups. CONCLUSION: The present investigation provides no evidence for a survival benefit of continuous vs intermittent RRT in ICU patients with ARF.     

Initial and delayed onset of acute respiratory failure: factors associated with development and outcome

In a prospective observational study of 1038 adult admissions to a 31-bed medical/surgical intensive care unit (ICU), acute respiratory failure (ARF, defined as a Pao(2)/Fio(2) ratio 48 h after ICU admission) in 49 (16%). On admission, the cardiovascular sequential organ failure assessment (SOFA) score was higher in initial than in delayed onset ARF (1.1 +/- 1.5 vs 0.6 +/- 1.2, P < 0.05). High admission serum C-reactive protein concentrations (OR 1.08, 95% CI 1.04-1.12, P = 0.0001) and SOFA scores (OR 1.20, 95% CI 1.08-1.33, P = 0.0007) were the factors independently associated with initial ARF, and a low Glasgow coma scale (GCS) score (OR 1.13, 95% CI 1.04-1.21, P = 0.0018) was associated with delayed onset ARF. In initial ARF, a high SOFA score (OR 1.24, 95% CI 1.12-1.38, P = 0.0001) and a low GCS score (OR 0.89, 95% CI 0.83-0.96, P = 0.0013) on admission, and in delayed onset ARF, a low GCS score at 48 h (OR 0.67, 95% CI 0.54-0.84, P = 0.0011) were independently associated with death. The mortality rate was similar for initial and delayed onset ARF.     

Re-evaluation and modification of the Stuivenberg Hospital Acute Renal Failure (SHARF) scoring system for the prognosis of acute renal failure: an independent multicentre, prospective study.

BACKGROUND: A prognostic scoring system for hospital mortality in acute renal failure (Stuivenberg Hospital Acute Renal Failure, SHARF score) was developed in a single-centre study. The scoring system consists of two scores, for the time of diagnosis of acute renal failure (ARF) and for 48 h later, each originally based on four parameters (age, serum albumin, prothrombin time and heart failure). The scoring system was now tested and adapted in a prospective study. METHODS: The study involved eight intensive care units. We studied 293 consecutive patients with ARF in 6 months. Their mortality was 50.5%. The causes of ARF were medical in 184 (63%) patients and surgical in 108 (37%). In the latter group, 74 (69%) patients underwent cardiac and 19 (18%) vascular surgery. RESULTS: As the performance of the original SHARF scores was much lower in the multicentre study than in the original single-centre study, we re-analysed the multicentre data to customize the original model for the population studied. The independent variables were the score developed in the original study plus all additonal parameters that were significant on univariate analysis. The new multivariate analysis revealed an additional subset of three parameters for inclusion in the model (serum bilirubin, sepsis and hypotension). For the modified SHARF II score, r(2) was 0.27 at 0 and 0.33 at 48 h, respectively, the receiver operating characteristic (ROC) values were 0.82 and 0.83, and the Hosmer-Lemeshow goodness-of-fit P values were 0.19 and 0.05. CONCLUSION: After customizing and by using two scoring moments, this prediction model for hospital mortality in ARF is useful in different settings for comparing groups of patients and centres, quality assessment and clinical trials. We do not recommend its use for individual patient prognosis.     

Validation of Liano score in acute renal failure: a prospective study in Indian patients

Aim  To validate Liano score as a prognostic scoring system in acute renal failure (ARF): a prospective study in Indian patients. Patients and methods  Prospective study including 100 patients over a period of 1 year, from March 2006 to July 2007. Inclusion criteria were patients with no previous renal disease or any systemic disease known to affect the kidney and who presented with acute rise (hours to days) in serum creatinine. Exclusion criteria were patients with preexisting chronic renal failure, age younger than 12 years and ultrasound of the abdomen showing contracted kidneys. Results and conclusions  In this study there were 68 males and 32 females. Peak incidence by age was in the fifth decade. There was no increased mortality in any age group (p = 0.278). A total of 19 patients had pre-renal ARF, 74 patients had intrinsic ARF, of which 46 were acute tubular necrosis (ATN); 7 patients had obstructive ARF. A total of 21 patients had Liano score greater than 0.9, of which 18 patients died and 3 were discharged against medical advice in a critical condition (and died later at home). Calculated sensitivity was 62.1%, specificity was 100% and positive predictive value was 100%. Sensitivity and specificity when calculated separately for intrinsic renal ARF (after excluding post renal ARF) were 60.7% and 100%, respectively. There was statistically significant correlation between Liano score and mortality (p < 0.001).     

Outcome in a post-cardiac surgery population with acute renal failure requiring dialysis: does age make a difference?

BACKGROUND: Acute renal failure (ARF), requiring dialysis (ARF-d), develops in 1-5% of patients undergoing cardiac surgery and is associated with higher in-hospital mortality. Age is one of the known risk factors for the development of ARF. As the ageing population is increasing, the nephrologist will be faced with a large population of elderly patients requiring dialysis following cardiac surgery. The aim of our study was to evaluate the influence of age on and the risk factors for in-hospital mortality. METHODS: Eighty-two patients with ARF following cardiac surgery and requiring dialysis between January 1997 and October 2001 were included. Two groups of patients were studied: the younger population (<70 years, 42 patients, mean age 59+/-10) and an elderly population (>/=70 years, 40 patients, mean age 76+/-4). Severity of disease was evaluated using the SAPS (Simplified Acute Physiology Score), the Liano score and the SHARF (Stuivenberg Hospital Acute Renal Failure) score. RESULTS: Overall mortality in the population with ARF-d was 56.1%. No difference in mortality rate was found between the younger (61.9%) and elderly patient group (50.0%). The two groups were very similar in baseline and procedural characteristics with exception of body weight (P=0.02) and preoperative glomerular filtration rate (P=0.0001). No significant difference was found in the scoring systems between the old and the young (SAPS P=0.52; Liano P=0.96; SHARF T0 P=0.06; SHARF T48 P=0.15). Mortality in the elderly was significantly correlated with hypotension before starting renal replacement therapy (RRT) (P=0.002), mechanical ventilation (P=0.002), presence of multiorgan failure (MOF) (P=0.0001) and higher scores in the severity models (SAPS: P=0.01; Liano: P<0.0001 and SHARF: P<0.0001). CONCLUSION: The outcome in the elderly requiring dialysis due to ARF post-cardiac surgery is comparable with the outcome in a younger population. No significant difference was found in severity of disease between the elderly and the younger. Variables predicting mortality in the elderly are the presence of MOF, mechanical ventilation and hypotension 24 h before starting RRT. These findings indicate that at the time the nephrologist is called for an elderly patient requiring dialysis due to ARF following cardiac surgery, age per se is not a reason to withhold RRT.     

Prognostic value of a new scoring system for hospital mortality in acute renal failure

AIM AND METHODS: In order to define a prognostic scoring system for hospital mortality of individual patients with acute renal failure (ARF), data were collected prospectively in a single centre study (Stuivenberg General Hospital, Antwerp, Belgium) on 197 adult patients consecutively admitted to the intensive care unit (ICU) during one year. Mean age was 69.8 (+/- 14.7), male/female ratio was 118/79. RESULTS: Hospital mortality was 53%, 26% of the patients who were treated with renal replacement therapy. For developing the model all parameters showing a significant difference between survivors and non-survivors were entered in the multivariate analysis. Two SHARF scores (= Stuivenberg Hospital Acute Renal Failure scores) were developed, one at the time of diagnosis of ARF (T0) and the other 48 hours later (T48): SHARF T0 (7 x age) + (6 x alb0) + (3 x PTT0) + (39 x vent0) + (9 x heartf0) + 52 SHARF T48 (7 x age) + (6 x alb0) + (3 x PTT0) + (43 x vent48) + (16 x heartf48) + 52 age, albumin (alb0) and prothrombine time (PTT0) at T0 are expressed as categories, respiratory support (vent) and heart failure (heartf) at T0 and T48 are presented as absent (0) or present (1). In the linear regression model, r2 was, respectively, 0.36 and 0.43. The area under the receiver operator characteristic (ROC) curves, judging the discrimination ability between survivors and non-survivors, for T0 and T48 were, respectively, 0.87 and 0.90. The Hosmer-Lemeshow goodness-of-fit C statistic for T0 was C = 8.47; df8; p = 0.3 89 and for T48 C = 11.05; df = 8; p = 0.199. CONCLUSION: We conclude that this scoring system, developed for all types of ARF, compares favorably with published scores and can become useful as a bedside tool for predicting hospital mortality in individual patients. A second measuring point increased the predictive value of the model. The results have to be confirmed in an ongoing prospective multicentre study.