Early prognostic factors in patients with acute renal failure requiring dialysis

PURPOSE: Despite improvements in renal therapy and technology, the mortality rate of patients with acute renal failure (ARF) remains high. Because ARF is a heterogeneous syndrome, occurring in patients with diverse etiologies and comorbid conditions, predicting its outcome is difficult. This study aims to identify early clinical and laboratory prognostic factors, including acute-phase reactants such as C-reactive protein (CRP), fibrinogen, and albumin, in ARF patients requiring dialysis. MATERIAL AND METHODS: From June 2002 to March 2004, 61 patients with ARF requiring dialysis at Chang Gung Memorial Hospital, Chiayi, were prospectively analyzed. For each patient, the worst values of prognostic variables 24 hr before starting dialysis were prospectively assessed. RESULTS: Oliguria, low plasma fibrinogen levels, hypotension, cardiac disease, and neoplastic disease were statistically significant in predicting hospital mortality. Using Youden's index, the best cut-off value for plasma fibrinogen in predicting mortality was 300 mg/dL with a sensitivity and specificity of 61% and 96%, respectively. Serum CRP and serum albumin were not predictive of hospital mortality. CONCLUSION: Early prognostic factors in predicting mortality for patients with ARF requiring dialysis identified by multivariate logistic regression were oliguria, low plasma fibrinogen, hypotension, cardiac disease, and neoplastic disease. Serum CRP and albumin were not predictive of hospital mortality, whereas a plasma fibrinogen level < or =300 mg/dL had 61% sensitivity and 96% specificity in predicting mortality.     

Prognosis in acute pancreatitis complicated by acute renal failure requiring dialysis

Acute pancreatitis complicated by acute renal failure (ARF) requiring dialysis is a rare condition with a mortality rate of 80%. During the period 1977-1988 419 patients were admitted to our hospital because of ARF requiring dialysis. Fourteen (3%) had ARF caused by acute pancreatitis. Ten patients developed respiratory failure, eight patients circulatory failure, four hepatic failure, and one disseminated intravascular coagulation. Three patients had complicating septicemia and two gastrointestinal bleeding. Ten patients (71%) died. All patients with four or more organ failures besides the pancreatic failure died. Median time from start of symptoms until death was 28 days. Mortality in this series does not differ from that reported over the last 40 years. The need of multicenter trials for the purpose of improving prognosis is emphasized.     

A clinical index to predict survival in acute renal failure patients requiring dialysis

Recent advances in technology have not substantially changed the relatively low survival rate associated with acute renal failure (ARF). Several clinical prognostic variables and multivariate models have been reported to predict survival in individual patients, but these are either cumbersome to use or restrictive in their application. A straightforward clinical index has been developed to predict survival in ARF based on data obtained for all patients receiving dialysis for ARF at the University of Kansas Medical Center from November 1979 through October 1985. During this period, 126 patients received dialysis for ARF, with an overall survival of 25% (32/126). There were no significant differences between survivors and nonsurvivors in age, gender, or indication for dialysis. Eleven variables were statistically related to survival, and were reduced to five when clinically similar variables were combined or eliminated. A clinical survival index was based on these five easily determined variables that were significantly related to survival: systolic blood pressure less than or equal to 110 mm Hg, assisted ventilation, congestive heart failure, proven or suspected sepsis, and gastrointestinal (GI) dysfunction (bleeding, ileus, obstruction, or recent abdominal surgery). Survival was directly related to the number of factors present: zero, 62% (8/13); one, 44% (8/18); two, 30% (10/33); three, 19% (5/26); four, 0% (0/20); and five, 6% (1/16). This straightforward index, derived from easily obtained clinical data, is useful for judging survival prognosis in patients with ARF severe enough to warrant treatment with dialysis.     

Outcomes and APACHE II predictions for critically ill patients with acute renal failure requiring dialysis

BACKGROUND: Despite the widespread availability of dialytic and intensive care unit technology, the probability of early mortality in critically ill patients with acute renal failure (ARF) is still high, and the evaluation of the patients' prognosis has been difficult. The Acute Physiology and Chronic Health Evaluation II (APACHE II) score is a reliable indicator of severity of illness and likelihood of survival in critically ill patients with ARF. We have attempted to determine whether the APACHE II scoring system can be used to predict prognosis. METHODS: A retrospective cohort study evaluated the medical records of 100 consecutive patients in intensive care units with acute renal failure who required dialysis from January 1997 through December 1998. RESULTS: Of the 100 patients studied, 65 were men and 35 were women. The mean age of survivors and nonsurvivors was 59.4 +/- 20.3 years and 58.3 +/- 20.0 years. The overall mortality rate was 71%. There were no significant differences between survivors and nonsurvivors in age, gender, or indication for dialysis. The cause of death in the majority of patients was related to higher APACHE II score during the 24 hours immediately preceding the initiation of acute hemodialysis, and carry mortality rates exceeding 85% with an APACHE II score of 24 or higher. CONCLUSION: We conclude that mortality rate for acute renal failure in intensive care unit patients continues to be high. 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. There is a significant trend with APACHE II score for outcome.     

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.     

Prognostic value of acute physiology and chronic health evaluation II and organ system failure in patients with acute renal failure requiring dialysis

BACKGROUND: Despite advances in modern technology of dialysis, prognosis of patients with acute renal failure (ARF) remains poor. To give the clinicians the most useful information, a model that accurately predicts outcome early in the course of ARF is required. However, because ARF is a heterogeneous syndrome and occurs in patients with diverse etiologies and some coexisting diseases, predicting outcome early is hard. The aim of this study is to evaluate prospectively the Acute Physiology and Chronic Health Evaluation (APACHE II) and organ system failure (OSF) models, evaluated prior to dialysis, in predicting hospital mortality. METHODS: From June 2002 to March 2004, ARF patients requiring dialysis at Chang Gung Memorial Hospital, Chiayi, were prospectively recruited for this study. The worst clinical and laboratory data in the 24 hours before initiation of dialysis were prospectively evaluated, and the patients' APACHE II score and OSF number were assessed. RESULTS: A total of 61 patients (40 male and 21 female) were enrolled, of whom 38 (62.3%) died before discharge. By multivariate logistic regression, the APACHE II score (odds ratio 1.3 per increase in one score; P<0.001), or OSF number (odds ratio 1.9 per increase in one OSF; P<0.01) and oliguria (odds ratio 4.2; P=0.04), were found to be statistically significant prognostic factors for hospital mortality. Mortality increased progressively and significantly as OSF number (chi-square for trend; P=0.001) or the APACHE II score (chi-square for trend; P < 0.001) increased. By using Youden's index, the best cut-off value for APACHE II was 24, with 63% sensitivity and 96% specificity. The best cut-off value for OSF number was 2, with a sensitivity of 81.6% and a specificity of 60.9%. The areas under the receiver operating characteristic curves for APACHE II and OSF number were 0.847 (95% confidence interval (CI)=0.752-0.942; P<0.01) and 0.769 (95% CI=0.646-892; P<0.001), respectively, indicating good model discrimination. CONCLUSIONS: This study concludes that APACHE II and OSF number measured prior to initiation of dialysis reliably predict outcomes of ARF patients requiring dialysis. The mortality rates increase as the APACHE II score or OSF number increases. For predicting mortality, the APACHE II score > or = 24 was found to have 63% sensitivity and 96% specificity, and OSF number> or = 2 had 81.6% sensitivity and 60.9% specificity.     

Hypercalcemia in patients with advanced chronic renal failure not yet requiring dialysis

Six patients with progressive chronic renal failure not yet requiring dialysis and not consuming supplemental calcium or vitamin D developed hypercalcemia. Three had proven and 1 suspected tertiary hyperparathyroidism, 1 parathyroid carcinoma and 1 aplastic bone. None of the 3 patients who underwent bone biopsy had heavy bone aluminum staining. The patients with proven parathyroid-mediated hypercalcemia had marked elevation of C-terminal parathyroid hormone and alkaline phosphatase values and, when performed, radiographs consistent with osteitis fibrosa. When these findings are absent or the diagnosis is otherwise uncertain, a bone biopsy may provide a definitive diagnosis and guide management.     

Prognosis in septicemia complicated by acute renal failure requiring dialysis.

During a 12-year period 419 patients were admitted because of acute renal failure requiring dialysis. Fifty (12%) had septicemia verified by blood culture. In a retrospective study age, sex, focus of infection, blood culture results, kidney function, mode of dialysis treatment, numbers and durations of complicating organ failures, presence of gastrointestinal bleeding, and secondary complicating events of septicemia were recorded for the purpose of establishing a prognostic index based on clinical criteria. Respiratory failure was present in 34 patients, circulatory failure in 31 patients, failure of coagulation system in 25 patients, and hepatic failure in 10 patients. Overall mortality was 46%. Highest death-rates were found during the first days of dialysis. In patients with multiple organ failures, in elderly and in patients suffering from staphylococcus aureus septicemia, a non-significant trend towards higher mortality was found. The mode of dialysis treatment did not influence patient survival. Our intention of establishing a prognostic index based on bedside clinical criteria has not been fulfilled. Even though mortality-rate increases in patients with acute renal failure complicated by failure of one or more vital organs, survival-rate in patients with four or more organ failures was 30%.     

Pregnancy in women requiring dialysis for renal failure

Pregnancy is an unusual occurrence in women with end-stage renal disease. When it occurs, spontaneous abortion, stillbirth, and neonatal death end 75% to 80% of the pregnancies. The mother is at risk for hypertension and abruptio placentae. The fetus is at risk for prematurity and growth retardation. Surviving infants appear to be normal. This report outlines the problems in 37 pregnancies (22 in the reported literature and 15 not yet reported). It outlines strategies for improving the chances of survival of the infant.     

Hyperprolactinemia in patients with renal insufficiency and chronic renal failure requiring hemodialysis or chronic ambulatory peritoneal dialysis

Hyperprolactinemia is common in patients with renal failure. Because radiographic contrast material given during a computed tomographic (CT) scan of the sella as part of the evaluation for prolactinoma worsens renal insufficiency, we attempted to define the point at which hyperprolactinemia becomes an expected finding in patients with renal insufficiency in this study. Of 59 patients with serum creatinine levels of 1.5 to 12 mg/dL, 16 (27.1%) were hyperprolactinemic. Of these 16, nine were not taking medications known to raise prolactin levels and their prolactin levels were less than 100 ng/mL. In the eight patients taking medications prolactin levels were much higher. In one patient the prolactin level fell from 2,210 to 100 ng/mL when methyldopa was discontinued. In patients with chronic renal failure prolactin levels were similar regardless of the method of dialysis. We conclude that in the absence of medications known to affect prolactin secretion, hyperprolactinemia occurs infrequently (18.3%) and, when it occurs, is mild (less than 100 ng/mL). Marked hyperprolactinemia may occur in patients taking such medications. These should be stopped and the prolactin level rechecked before a CT scan is performed.     

Outcomes of acute renal failure patients requiring intermittent hemodialysis

The published studies on the prognosis of patients requiring intermittent hemodialysis (IHD) are scarce and have some conflicts. In this study, we retrospectively analyzed our data on ARF patients who were treated with IHD. A total of 192 (female: 85, 44.3%; male: 107, 55.7%) patients were included in the study. The mean age was 56.3 +/- 17.1 years. In all, 48.9% of the patients were older than 60 years. The mean number of IHD sessions was 7.8 +/- 8.0 per patient; 12.4% was due to prerenal causes, 76.8% was due to intrarenal causes, and 10.8% was due to postrenal causes. The leading indication of the IHD was uremic symptoms (46.8%). With the exclusion of hypertension, 72.4% of the patients had at least one systemic comorbidity. After treatment, 75.5% of the patients recovered, in contrast to 9.4% of patients who were transferred to chronic renal replacement programs and 15.1% who died during IHD period. Pre-dialytic serum creatinine (p = 0.003) and albumin levels (p = 0.016), total IHD session number per patient (p = 0.003), and age (p = 0.034) were the parameters that were related to high mortality in statistical analysis. Mortality was higher if the leading indication of IHD was biochemical disturbances (p = 0.013). Diabetes mellitus did not influence mortality. Consequently, predialytic serum creatinine and albumin levels may be very important predictors of mortality. Patients in high-risk groups (older age, female sex, and low pre-dialytic creatinine and albumin levels) should be considered to be treated with slow continuous renal replacement methods.     

Hypotension during acetate and bicarbonate dialysis in patients with acute renal failure

Bicarbonate dialysate is claimed to be superior to acetate for both chronic and acute hemodialysis. We compared acetate and bicarbonate dialysates in 30 acute renal failure patients during 120 dialyses. 4 patients were diabetic and 2 had liver failure. Patients were dialyzed alternating acetate and bicarbonate dialysate in a double-blind cross-over manner; each patient was his own control. BUN, creatinine, Na+, K+, osmolality, delta osmolality, % ultrafiltration, arterial blood gases, pre, post and lowest dialysis mean arterial blood pressure, dialysis with hypotensive episodes and symptoms of hypotension were recorded. The measurements obtained for each patient during dialyses with acetate and bicarbonate were compared. There was no difference in predialysis chemistries, osmolality or osmolality fall, no change in mean arterial blood pressure or hypotensive episodes and symptoms and ultrafiltration. PCO2 and pH were slightly lower for the acetate group at the 2nd h but not at the end of dialysis. 4 patients had serum acetate determinations, all metabolized acetate normally. These findings contradict recent suggestions that severely ill patients should not be dialyzed against acetate. Since acetate is technically much easier to use and has no clinical drawbacks, it does not need to be replaced with bicarbonate in acute patients. Other factors must be more important than acetate in generating hypotension during acute dialysis.     

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.     

Adequacy of dialysis in acute renal failure

Renal replacement therapy (RRT) is currently the mainstay of management for patients with acute renal failure (ARF). Adequacy of dialysis in the setting of renal failure is defined poorly and encompasses multiple domains of clinical and biochemical outcomes. Multiple operational factors influence the delivery of adequate dialysis. No current standards exist for RRT for ARF; current RRT practices for ARF generally have been extrapolated from end-stage renal disease (ESRD) literature. The heterogeneity of patient population, variation in RRT practices, and differences in outcomes studied have made it difficult to define or study adequate dialysis in ARF or its impact on clinical outcomes.     

Dose of dialysis in acute renal failure

Acute renal failure (ARF) is a cause of significant morbidity and mortality. Despite advances in supportive care, outcomes in ARF have improved little over the past decades. The primary goals in management of patients with ARF are to optimize hemodynamic and volume status, minimize further renal injury, correct metabolic abnormalities, and permit adequate nutrition. Renal replacement therapy (RRT) is often required to achieve these goals while awaiting renal recovery, but the optimal dose of dialysis in patients with ARF is not known. Extrapolation of required dialysis dose from recommendations in chronic dialysis is unlikely to be appropriate because of the lack of a steady state and differences in distribution volume of urea that are intrinsic to ARF. The prescribed dialysis dose in ARF is often low, and actual delivered dose is often even less than prescribed. Delivery of dialysis in ARF is often hampered by the patient's hypercatabolic state, hemodynamic instability, and volume status, as well as suboptimal vascular access with temporary venous catheters. The impact of intermittent hemodialysis (IHD) versus continuous renal replacement therapy (CRRT) on outcomes in ARF is also not clear. Patient disease severity impacts more than dialysis modality in patient outcome, but when patients are stratified for equal disease severity, CRRT may have potential benefits over IHD in terms of patient survival, fluid and metabolic control, and renal recovery. Strategies associated with improved outcomes that have emerged thus far in ARF are to aim for a time-averaged blood urea nitrogen (BUN) of less than 60 mg/dl with IHD, varying IHD frequency as necessary, or to achieve a minimum ultrafiltration rate of 35 ml/kg/hr with CRRT.     

心脏瓣膜手术后并发透析依赖的急性肾功能衰竭的危险因素

目的 探讨心脏瓣膜手术后并发透析依赖的急性肾功能衰竭(acute renal failure requiringdialysis,ARF-D)的危险因素.方法 回顾性分析2005年1月至2008年12月心脏瓣膜手术、年龄≥18岁、术前血肌酐＜300 μmol/L的病例资料.术后30天内并发ARF-D者为病例组,共55例.随机抽取同期未并发ARF-D的220例作为对照组.采用单因素分析及多因素Logistic回归探讨并发ARF-D的危险因素.结果 心脏瓣膜术后ARF-D发生率为1.78%,早期病死率65.5%.Logistic回归分析结果显示年龄、二次手术、术前血肌酐、心功能(NYHA)Ⅳ级、术后低心排血量综合征为心脏瓣膜术后并发ARF-D的独立危险因素.病例组与对照组相比,监护室停留时间、术后住院时间差异有统计学意义(P＜0.05).结论 年龄、二次手术、术前血肌酐、心功能Ⅳ级、术后低心排血量综合征为心脏瓣膜术后并发ARF-D的独立危险因素.

Abstract：

Objective To evaluate the risk factors for the postoperative acute renal failure requiring dialysis (ARF-D)after heart valve surgery. Methods Adult patients (age≤18 years) underwent valve surgery with preoperative serum creatinine ＜300 μmol/L were included between January 2005 and December 2008. Fifty patients developed ARF-D within 30 days postoperatively (ARF-D group). While random 220 patients had the same operation without ARF-D served as the control group. Univariate analysis and multivariable logistic regression were used to identify risk factors of ARF-D after valve surgery.Results The incidence of ARF-D was 1.78%, and the early mortality rate was 65.5%. Multivariate analysis identified the following independent risk factors of ARF-D: age, previous cardiac surgery, preoperative serum creatinine, NYHA class Ⅳ,and low cardiac output syndrome. ARF-D group had a longer hospital stay and ICU stay than that of the control group ( P ＜0.001 ). Conclusion Conclusion ARF-D had a higher mortality rate and longer hospital stay following heart valve surgery.Age, previous cardiac surgery, preoperative serum creatinine, NYHA class Ⅳ, and low cardiac output syndrome were the independent risk factors of ARF-D after heart valve surgery.