Early and intensive continuous hemofiltration for severe renal failure after cardiac surgery

BACKGROUND: The aim of this study was to test whether early and intensive use of continuous venovenous hemofiltration (CVVH) achieved a better than predicted outcome in patients with severe acute renal failure undergoing cardiac operations, and whether a simple and yet accurate model could be developed to predict their outcome before starting CVVH. METHODS: Medical record analysis with collection of demographic, clinical, and outcome information was used. RESULTS: Sixty-five consecutive patients were treated with early and intensive CVVH (mean operation to CVVH time, 2.38 days; pump-controlled ultrafiltration rate, 2 L/h) after coronary artery bypass grafting (56.9%), single valve procedure (16.9%), or combined operations (26.2%). In 32.3% of patients, intraaortic balloon counterpulsation was required and 20% of patients were emergencies. Sustained hypotension despite inotropic and vasopressor support occurred in 40% of patients and prolonged mechanical ventilation in 58.5%. Using an outcome prediction score specific for acute renal failure, the predicted risk of death was 66%. Actual mortality was 40% (p = 0.003). Using multivariate logistic regression analysis and neural network analysis, patient outcome could be predicted with good levels of accuracy (receiver operating characteristic 0.89 and 0.9, respectively). CONCLUSIONS: Early and aggressive CVVH is associated with better than predicted survival in severe acute renal failure after cardiac operations. Using readily available clinical data, the outcome of such patients can be predicted before the implementation of CVVH.     

Evaluation of continuous veno-venous hemofiltration for the treatment of cardiogenic shock in conjunction with acute renal failure after cardiac surgery

Background: Cardiogenic dysfunction with acute renal failure (ARF) and diuretic drug resistance increases mortality after cardiac surgery with cardiopulmonary bypass (CPB) in adults. Until few years ago, intermittent renal replacement therapy (IRRT) was the only therapeutical strategy proposed to such patients. Few data are available in the literature regarding the use of continuous veno-venous haemofiltration (CVVH) in this clinical context. The aim of our observational study was to evaluate the impact of CVVH strategy on ARF in conjunction with cardiogenic shock after cardiac surgery and on its well-known associated poor outcome. Methods: During the period 2005–2006, we prospectively collected data from our database as we controlled the renal replacement therapy using CVVH (n = 73). We also retrospectively collected data from our computerised database on patients who were treated with IRRT (n = 68, period 2002–2003). Among CVVH-treated patients, a multivariate analysis of the data aimed to identify risk factors associated with 30-day mortality. Results: In patients who presented with ARF in conjunction with cardiogenic shock after cardiac surgery, 30-day mortality rate was 59% for the IRRT group and 42% for the CVVH group. Within the CVVH group, the logistic regression and multivariate analyses reported that some variables were associated with higher mortality risk: a score F concerning the urinary output criteria of the RIFLE (risk, injury, failure, loss, end-stage kidney disease) classification (for scores R or I: odds ratio (OR): 0.01, 95% confidence interval (95% CI): 0.02–0.59; p = 0.01), plasma bilirubin (OR: 1.44, 95% CI: 1.12–1.84; p = 0.04), total CVVH duration <50 h over 72 h (>50 h; OR: 0.009, 95% CI: 0.04–0.93; p = 0.01), the need of catecholamine support (OR: 12.88, 95% CI: 1.95–84.96; p = 0.01), tachycardia in the intensive care unit (ICU; OR: 1.64, 95% CI: 1.02–2.65; p = 0.04), surgery duration (<300 min; OR: 0.11, 95% CI: 0.02–0.71; p = 0.02) and combined cardiac surgery (OR: 7.00, 95% CI: 1.29–37.88; p = 0.02). Conclusion: In patients with ARF in conjunction with cardiogenic shock after cardiac surgery, renal replacement therapeutic strategy based on long-lasting CVVH could improve patients’ outcome. The identification of risk factors associated with a poor outcome would help to better manage such patients in the ICU. Low total duration of CVVH within the first 72 h was one criteria related to poor outcome. This suggests that CVVH must be initiated as soon as possible when ARF with diuretic resistance occurs in patients after cardiac surgery and continued as long as possible for the first 3 days.     

Sustained low-efficiency dialysis versus continuous veno-venous hemofiltration for postsurgical acute renal failure

Background

In postsurgical acute renal failure patients with moderate unstable hemodynamics or fluid overload, the choice of dialysis modality is difficult. This study was performed to compare the outcomes between the sustained low-efficiency dialysis (SLED) and continuous veno-venous hemofiltration (CVVH) in these patients.

Methods

Sequential postsurgical acute renal failure patients undergoing acute dialysis with CVVH (2002-2003), or SLED (2004-2005) as a result of severe fluid overload or moderately unstable hemodynamics were analyzed. Multivariate analyses of comorbidity, disease severity before initiating dialysis, biochemical measurements, and hemodynamic parameters for 3 days after the first dialysis session were performed by fitting multiple logistic regression models to predict patient's 30-day after hospital discharge (AHD) mortality.

Results

Among the 101 recruited patients, 38 received SLED and the rest received CVVH. The 30-day AHD mortality was 62.4%. The independent risk factors of 30-day AHD mortality included older age (P = .008), lower first postdialysis mean arterial pressure (MAP) (P = .021), higher first postdialysis blood urea nitrogen level (P = .009), and absence of a history of hypertension (P = .002). A further linear regression analysis found that dialysis using SLED was associated with higher first postdialysis MAP (P = .003).

Conclusions

Among the postsurgical patients requiring acute dialysis with severe fluid overload or moderately unstable hemodynamics, the patients treated with SLED had a higher first postdialysis MAP than those treated with CVVH, which led to lower mortality. Further multicenter randomized clinical trials of larger sample size are needed to compare the effects of SLED and CVVH on the outcomes of postsurgical acute dialysis patients.     

Continuous hemofiltration vs hemodialysis for the acute renal failure after cardiovascular surgery

Recently we have performed continuous hemofiltration (CHF) for the patients of acute renal failure after cardiovascular surgery. In this article, we discuss the effectiveness of CHF in the acute phase of renal failure after cardiovascular surgery compared with hemodialysis (HD). CHF group included 12 cases, and HD group included 19 cases. Two cases (16.7%) of CHF group and two cases (10.5%) of HD group were survived and discharged from hospital. Filtration volume of CHF (93.8 +/- 81.0 l) was significantly higher than that of HD (27.1 +/- 22.9 l), but filtration rate of CHF (410 +/- 87.4 ml/H) was significantly lower than that of HD (572 +/- 167 ml/H). Thus CHF removed excess water more gently and effectively than HD. Because the influence to the hemodynamics of CHF was much less than that of HD, we were able to start CHF (4.3 +/- 4.6 days after operation, BUN: 55.3 +/- 19.5 mg/dl), Cr: 3.95 +/- 0.63 mg/dl) significantly earlier than HD (7.8 +/- 4.1 days after operation, BUN: 113.1 +/- 29.4 mg/dl, Cr: 6.10 +/- 1.04 mg/dl). We needed high dose catecholamine or blood transfusion for the 11 cases (57.3%) of HD group during HD, but we needed them for only 1 case (8.3%) of CHF group. We concluded that CHF was safer and more useful than HD in the treatment of acute renal failure after cardiovascular surgery.     

Erythropoietin in patients with acute renal failure and continuous veno-venous haemofiltration

Erythropoietin (Epo) is a glycoprotein hormone produced in the kidney in response to hypoxia or anaemia. In acute renal failure (ARF) anaemia also occurs and current opinion is that Epo production is depressed with inappropriately low plasma levels throughout the uraemic phase. Our study was designed to determine the excretion of Epo in patients with ARF. Fifty-nine ventilated patients were studied, 39 with ARF and continuous veno-venous haemofiltration therapy (group 1) and 13 patients with normal renal function who served as a control group (group 2). All patients with ARF were anaemic and needed a mean transfusion of 0.6 units/day. Values for vitamin B12, folic acid, serum iron and ferritin were normal. While patients with normal renal function had Epo values within the normal range, patients with ARF had significantly higher values at the onset of haemofiltration therapy. Mean Epo (mean±SEM) values on days 0–2 were 92.6±11.7 mU/ml in group 1 and 16.5±6.4 mU/ml in group 2 (p<0.0002). Epo levels declined in group 1 to 49±10.5 mU/ml on days 9 and 10 compared to 23±9.1 mU/ml in group 2 (ns). These values were maintained until the end of the observation period. No differences were seen between oliguric and non-oliguric patients. Our data show that patients with ARF have increased Epo levels at the beginning of the disease with a strong tendency to decrease, suggesting that there might be inadequate Epo levels during the course of acute renal failure.     

腹腔感染合并急性肾功能衰竭患者连续静脉-静脉血液滤过治疗前后血浆氨基酸水平变化

目的 探讨腹腔感染合并急性肾功能衰竭患者连续静脉-静脉血液滤过(CVVH)治疗前后血浆氨基酸水平变化和氨基酸丢失量.方法 回顾性分析2008年9月至2009年9月南京军区南京总医院收治的10例腹腔感染合并急性肾功能衰竭患者的临床资料.采用AV600S聚砜膜行24 h CVVH治疗,分别采集CVVH治疗前、治疗12 h和24 h血浆,连续收集24 h滤液.高压液相色谱测定血浆和滤液氨基酸浓度,并计算滤液氨基酸丢失量.采用配对t检验或Wilcoxon秩和检验,一元线性回归分析变量之间的关系.结果 10例患者中死亡6例,其中3例死于脓毒性休克,3例死于MODS.CVVH治疗24 h后血浆各种氨基酸水平显著下降,其中组氨酸、异亮氨酸、半胱氨酸和谷氨酰胺分别由(22.1±10.3)、(20.0±7.6)、(10.3±4.7)、(122.3±72.2)μmoL/L下降至(5.6±3.4)、(6.4±2.5)、(2.9±2.4)、(42.5±33.6)μmol/L.血浆总氨基酸水平呈下降趋势,CVVH治疗12 h和24 h分别下降52%和59%.滤液氨基酸24 h平均丢失量为(9631±1089)mg/d,其中非必需氨基酸和必需氨基酸丢失量分别为(5072±618)mg/d和(3747±654)mg/d,两者比较,差异有统计学意义(t=4.52,P＜0.05).CVVH治疗12 h后滤液氨基酸丢失量和血浆氨基酸水平之间呈正相关(r=0.68,P＜0.05).结论 腹腔感染患者接受CVVH治疗时,氨基酸可以经滤液丢失,因此,为CVVH患者制定营养方案时,滤液额外丢失的氨基酸需要考虑在内,尤其要适当增加非必需氨基酸的含量.     

Timing of replacement therapy for acute renal failure after cardiac surgery

OBJECTIVE: Acute renal failure (ARF) following cardiac surgery remains a significant cause of mortality. The aim of this study is to compare early and intensive use of continuous veno-venous hemodiafiltration (CVVHDF) with conservative usage of CVVHDF in patients with ARF after cardiac surgery. MATERIALS AND METHODS: Due to ARF, CVVHDF was required in two groups of a total of 61 adult patients (1.79% of all patients). Group 1 included 27 patients while Group 2 included 34 patients. CVVHDF was performed on Group 1 when creatinine level exceeded 5 mg/dL, or potassium level exceeded 5.5 mEq/L irrespective of the urine output. CVVHDF was performed on Group 2 when urine output was less than 100 mL within consecutive 8 hours, with no response to 50 mg furosemide with the supplementary criterion that urine sodium concentration should be >40 mEq/L before the administration of furosemide. RESULTS: The mean elapsed time between the surgery and the initiation of CVVHDF was 2.56 +/- 1.67 days in Group 1 and 0.88 +/- 0.33 days in Group 2 (p = 0.0001). The mean intensive care unit (ICU) stay for Group 1 was 12 +/- 3.44 days and 7.85 +/- 1.26 days for Group 2 (p = 0.0001). ICU mortality rate was 48.1% for Group 1 and 17.6% for Group 2 (p = 0.014). The overall hospital mortality rate was 55.5% for Group 1 and 23.5% for Group 2 (p = 0.016). CONCLUSION: Recognition of ARF and early beginning of the CVVHDF are extremely important. The sooner the ARF after surgery is recognized and CVVHDF is performed, the higher the likelihood of the reduction of the hospital mortality.     

Torsemide versus furosemide after continuous renal replacement therapy due to acute renal failure in cardiac surgery patients

Diuretic therapy in ARF (acute renal failure) is mainly done with loop diuretics, first of all furosemide. Torsemide has a longer duration of action and does not accumulate in renal failure. In chronic and acute renal failure, both diuretics have been effectively applied, with a more pronounced diuretic effect for torsemide. In this study, the effects of torsemide versus furosemide on renal function in cardiac surgery patients recovering from ARF after continuous renal replacement therapy (CRRT) were studied. Twenty-nine critically ill patients admitted to an intensive care unit at a university teaching hospital after cardiac surgery recovering from ARF after CRRT were included in this prospective, controlled, single-center, open-labeled, randomized clinical trial. Inclusion criteria were urine output >0.5 mL/kg/h over 6 h under CRRT. Torsemide and furosemide dosages were adjusted with the target urine output being 0.8-1.5 mL/kg/h. Hemodynamic data, urine output, volume balance, serum creatinine clearance, electrolytes, blood urea nitrogen, serum creatinine, renin, and aldosterone concentrations were measured. Fourteen patients were included in the furosemide group and 15 patients in the torsemide group. Dosages of 29 (0-160) mg torsemide and a dosage of 60 (0-240) mg furosemide were given every 6 h in each group, respectively. The dosage given at the end of the study decreased significantly in furosemide and torsemide treated patients. Urine output, 24 h balance, and serum creatinine clearance did not differ significantly between groups. Urine output decreased in both groups, mostly dose-dependent in the torsemide group. The intragroup comparison of the first time-interval after inclusion with the last time-interval showed a significant increase in serum creatinine and blood urea nitrogen in the furosemide group. Renin and aldosterone concentrations did not show significant differences. In conclusion, torsemide and furosemide were effective in increasing urine output. Torsemide might show a better dose-dependent diuretic effect in ARF patients after CRRT treatment. Serum creatinine and blood urea nitrogen elimination were less pronounced in the furosemide group.     

Treatment of acute renal failure in newborns by continuous arterio-venous hemofiltration

The treatment of acute renal failure (ARF) in the newborn with hemo- or peritoneal dialysis is technically difficult and may even be contraindicated. As in the adult, continuous arterio-venous hemofiltration (CAVH) may be an alternative therapy. We used CAVH in the treatment of four newborns with ARF of different etiology. Two brachial, one femoral and one umbilical arteries were cannulated as arterial access, while three jugular and one umbilical veins were used as venous return. An Amicon 0.005 m2 Polysulphon Hollow Fiber hemofilter was connected to the patient with shortened pediatric hemodialysis lines. Total blood volume of the extracorporeal circuit was 15 to 22 ml. Before starting the procedure, an initial bolus of heparin was administered to the patient (100 i.u./kg body wt) and a successive continuous heparin administration was provided during the treatment at the rate of 5 to 7 i.u./kg/hr. Hyperalimentation and/or buffer solutions were used as replacement fluids and were administered according to the patient's fluid balance. mean data in the four patients are summarized as follows. The age of the patients ranged from two to 12 days, while the average body weight was about 3 kg. The ultrafiltration rate during the treatment averaged 0.9 ml/min with a plasma flow ranging from 9.8 to 19.6 ml/min. The treatment duration varied from 30 to 86 hrs. The treatment was well tolerated (patients 1 and 2 recovered, and patients 3 and 4 died due to complications unrelated to the treatment). Arterial pressure remained stable during the procedure. Metabolic acidosis, when present, was corrected by increasing the amount of buffer administered. BUN was maintained below 60 mg/dl in three patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Outcome prediction for critically ill children with acute renal failure requiring continuous hemofiltration

Continuous hemofiltration has been used with increasing frequency for treating volume overload and acute renal failure in critically ill, hemodynamically unstable pediatric patients. This retrospective report investigates continuous hemofiltration in pediatric patients, and their survival rate. Sixty children treated between 1999 and 2001 with a diagnosis of acute renal failure and requiring continuous hemofiltration were admitted to this study to determine if pediatric risk of mortality III (PRISM III) scores were an accurate prediction of mortality. PRISM III scores were calculated on the day continuous hemofiltration commenced; mean PRISM III scores of non-survivors were significantly higher than mean scores of survivors. PRISM III scores may be a useful indicator of outcome in children receiving continuous hemofiltration.     

The incidence and risk of acute renal failure after cardiac surgery

OBJECTIVE: To evaluate outcome and risk factors of acute renal failure in a surgical population with or without preoperative renal dysfunction. DESIGN: Observational study. SETTING: Intensive care unit at a University Hospital. PARTICIPANTS: Five thousand sixty-eight consecutive adult patients who underwent cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: Perioperative variables measured were age, sex, basic pathology, preoperative renal impairment defined as creatinine >1.4 mg/dL, ventricular dysfunction, preoperative neurologic event, chronic obstructive pulmonary disease, diabetes, type of surgery, use of intra-aortic balloon pump (IABP), cardiopulmonary bypass (CPB) duration, redo or emergency surgery, hemorrhage, blood transfusion, surgical revisions, and postoperative complications. MEASUREMENTS and MAIN RESULTS: Acute renal failure (100% creatinine increase) developed in 171 (3.4%) patients, whereas 94 patients (1.9% of the population) had renal replacement therapy. Hospital mortality was 40.9% in patients with acute renal failure and increased to 63.8% when renal replacement therapy was requested. Sex, age, emergency surgery, low ejection fraction, IABP device, redo, diabetes, mitral valve surgery, CPB duration, and preoperative renal disease were independently associated with acute renal failure at a multivariate analysis. CONCLUSION: This study confirms that acute renal failure is one of the major complications of cardiac surgery, identifies the risk factors, and suggests that optimizing cardiac output and reducing CPB time could improve the outcome of patients at high risk of acute renal failure.     

Continuous venovenous hemofiltration: an alternative to continuous arteriovenous hemofiltration and hemodiafiltration in acute renal failure

Continuous venovenous hemofiltration (CVVH) has been used as an alternative to continuous arteriovenous hemofiltration (CAVH) and hemodiafiltration (CAVHD) in the management of critically ill patients with acute renal failure. This report describes our experience with the first 25 patients treated with CVVH at our institution. Vascular access was obtained through a single dual-lumen venous catheter. A blood pump was used to provide ultrafiltration pressure. An ultrafiltrate pump was incorporated to ensure predictable ultrafiltrate production rates. Safety features in the extracorporeal circuit included a venous drip chamber with bubble detector and an in-line pressure monitor. CVVH was initiated by a nephrologist and dialysis nurse and was maintained by the intensive care unit (ICU) nursing staff. Fifteen females and 10 males received CVVH therapy for a total of 193.5 days (average, 7.7 +/- 10.3 days; range, 0.5 to 48 days). Four of the 25 patients (16%) survived and were discharged from the hospital. Four additional patients (16%) survived the acute phase of their illness, but died from complications of their primary disease before discharge from the hospital. The mean weight change during CVVH was -7.9 +/- 7.0 kg (range, -26.5 to +2.9 kg). Metabolic waste products and electrolytes were adequately controlled by CVVH in all but one hypercatabolic patient. The mean heparin dose required was 6.5 +/- 4.2 U/kg/h and was adjusted to prevent filter clotting rather than to achieve a predetermined activated partial thromboplastin time (PTT). The median PTT was 35.8 seconds (range, 22.0 to 100; control, 19.5 to 29.5 seconds). Four episodes of volume-responsive hypotension occurred during the 193.5 treatment days. Only one patient experienced a hemorrhagic complication during CVVH. No patient experienced a complication related to vascular access. Twelve of 111 total hemofilters were changed because of clot formation. CVVH was well tolerated by patients and managed efficiently by the ICU nursing staff.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hepatoactive substances eliminated by continuous venovenous hemofiltration in acute renal failure patients

BACKGROUND: Acute renal failure (ARF) in critically ill patients is mostly part of a multi-organ failure. Therefore, the effects of renal replacement therapy on the liver are clinically important. We investigated the effects of ultrafiltrates of patients treated with continuous venovenous hemofiltration (CVVH) on liver cells in vitro. METHODS: Patients with ARF were consecutively treated with CVVH using Multiflow60 (group I) or FH66 filters (group II). They were comparable with respect to diagnosis, age, sex, laboratory parameters, and renal replacement treatment, but were different in daily diuresis, serum levels, and blood flow. Ultrafiltrates were collected within the first 10 minutes after change of hemofilter. Proliferation (bromodeoxyuridine), vitality (lactate dehydrogenase), and acute-phase protein secretion of HepG2 cells were measured. RESULTS: Ultrafiltrates changed liver cell function significantly compared with medium control. Proliferation (group I 29.8+/-5.2% vs. group II 48.4+/-6.6%, P < 0.05) and vitality (group I 78.7+/-2.0% vs. group II 87.6+/-1.7%, P < 0.01) of HepG2 cells were significantly different. On the one hand, the secretion of the negative acute-phase protein transferrin [group 13.1+/-0.2 (ng/microg protein) vs. group II 5.1+/-0.5 (ng/microg protein), P < 0.01] was significantly reduced by Multiflow60 ultrafiltrates. On the other hand, positive acute-phase protein alpha1-acid glycoprotein was significantly stimulated by Multiflow60 ultrafiltrates [group I 2.6+/-0.1 (ng/microg protein) vs. group II 1.7+/-0.1 (ng/microg protein), P < 0.001]. CONCLUSION: This study demonstrates hepatoactive mediators in the ultrafiltrates. They are hepatotoxic and influence acute-phase protein metabolism. Further studies have to elucidate the different effects in both groups and the analysis of the putative mediator(s). It remains a challenging task to consider therapeutic measures to optimize renal replacement therapy in critically ill patients.     

A clinical score to predict acute renal failure after cardiac surgery

The risk of mortality associated with acute renal failure (ARF) after open-heart surgery continues to be distressingly high. Accurate prediction of ARF provides an opportunity to develop strategies for early diagnosis and treatment. The aim of this study was to develop a clinical score to predict postoperative ARF by incorporating the effect of all of its major risk factors. A total of 33,217 patients underwent open-heart surgery at the Cleveland Clinic Foundation (1993 to 2002). The primary outcome was ARF that required dialysis. The scoring model was developed in a randomly selected test set (n = 15,838) and was validated on the remaining patients. Its predictive accuracy was compared by area under the receiver operating characteristic curve. The score ranges between 0 and 17 points. The ARF frequency at each score level in the validation set fell within the 95% confidence intervals (CI) of the corresponding frequency in the test set. Four risk categories of increasing severity (scores 0 to 2, 3 to 5, 6 to 8, and 9 to 13) were formed arbitrarily. The frequency of ARF across these categories in the test set ranged between 0.5 and 22.1%. The score was also valid in predicting ARF across all risk categories. The area under the receiver operating characteristic curve for the score in the test set was 0.81 (95% CI 0.78 to 0.83) and was similar to that in the validation set (0.82; 95% CI 0.80 to 0.85; P = 0.39). In conclusion, a score is valid and accurate in predicting ARF after open-heart surgery; along with increasing its clinical utility, the score can help in planning future clinical trials of ARF.     

三种心脏外科术后急性肾功能衰竭预测模型的临床应用

目的 分析克利夫兰急性肾功能衰竭评分(Cleveland ARF Score)、心脏术后急性肾功能不全评分(acute kidney injury prediction following elective cardiac surgery,AKICS)、简易肾功能指数评分(Simplified Renal Index,SRI score)三种模型在预测心脏术后发生急性肾功能衰竭中的作用,评价三种模型的预测价值.方法 2009年6月至2010年5月,连续收集了行心脏手术并有完整资料的患者504例纳入研究,分别使用Cleveland、AKICS、SRI评分系统进行校准度和分辨力的评价,分析并比较三种评分系统模型对术后发生急性肾功能衰竭的预测价值.结果 504例中术后需要肾脏替代治疗(renal re-placement therapy,RRT) 16例(3.17％),其中6例死亡(37.5％);发生肾功能不全27例(5.36％),经治疗后肾功能恢复正常.应用AKICS模型术后需要RRT治疗11例(2.70％),发生肾功能不全25例(6.13％),模型全组预计发生率3.77％.Cleveland评分术后需要RRT治疗16例(3.17％),发生肾功能不全27例(5.36％),模型全组预计发生率0.99％.SRI评分术后需要RRT治疗15例(3.21％),发生肾功能不全24例(5.13％).与预测结果比较,AKICS模型表现出较好的校准度(P=0.922,x2=0.162),Cleveland模型校准度差异有统计学意义(P=0.026,x2=15.644).Cleveland Score、AKICS、SRI 预测术后急性肾功能衰竭需行RRT治疗的ROC曲线下面积分别为0.695、0.732、0.759,术后肾功能不全的ROC曲线下面积分别为0.711、0.753、0.779.结论 结果显示,SRI模型预测术后RRT治疗及肾功能不全的实际危险度相关性较好.AKICS模型预测术后肾功能不全的实际危险度相关性较好.SRI模型的校准度及分辨能力均较好,可能较适用于评估患者的相对危险度.AKICS模型对于研究设计及选择治疗方案有一定使用价值.     

Early hemofiltration improves survival in post-cardiotomy patients with acute renal failure.

OBJECTIVE: The application and timing of hemofiltration (continuous veno-venous hemofiltration, CVVH) in patients with acute renal failure (ARF) post cardiac surgery has been called into question because of uncertain short-term outcome. The aim of the present study was to identify how the timing of introduction of hemofiltration affects the morbidity and mortality in patients with ARF after cardiac surgery. METHODS: 1264 consecutive patients who underwent adult cardiac surgical procedures performed between January 2002 and January 2003 were audited. Out of these, case notes of 64 patients who required renal supportive intervention were reviewed. Statistical significance was accepted at a level of P<0.05. RESULTS: Of the 64 (5%) patients, who developed ARF and required CVVH, there were 48 males and 16 females. Mean age was 70+/-6.8 years. The hospital mortality was 43% (12 patients) in Group-I and 22% (8) in Group-II (P<0.05), giving an overall 1.5% mortality associated with ARF. The mean time between the operation and the initiation of CVVH was 2.55+/-2.2 days in Group-I and 0.78+/-0.2 days in Group-II (P<0.001). The mean duration of CVVH was 4.57+/-11.4 days in Group-I and 4.61+/-2.0 days in Group-II (P=NS). Older age (P=0.013), elevated preoperative creatinine (P=0.002), postoperative pulmonary oedema (P=0.01), sepsis (P=0.001), multiple organ failure (P=0.031), hypotension (P=0.031) and preoperative renal failure (P<0.05) were the independent factors influencing the poor postoperative outcome and cardiac instability. CONCLUSION: Early and aggressive use of CVVH is associated with better than expected survival in severe ARF after cardiac operations.     

Rapid removal of vancomycin by continuous veno-venous hemofiltration

We describe a 14-year-old girl with staphylococcal (coagulase-negative) ventriculo-peritoneal shunt infection, who developed oliguric acute renal failure and was found to have a serum vancomycin concentration of 250 microg/ml. Since only about 10%-50% of vancomycin is bound to protein in blood, we employed continuous veno-venous hemofiltration (CVVH) with a high ultrafiltration rate (1,800 ml/h) for increased convective clearance to remove vancomycin, which may have contributed to the acute renal failure. At the end of 38 h of CVVH, the vancomycin concentration had decreased in an exponential manner to 27 microg/ml. Over the subsequent 3-4 days, her renal function improved and the vancomycin concentration decreased further to <5 microg/ml. In conclusion, we believe that a high serum vancomycin concentration may be nephrotoxic and demonstrate that CVVH can be used effectively to remove vancomycin in children with acute renal failure.