A systematic review of continuous renal replacement therapy and intermittent haemodialysis in management of patients with acute renal failure

Background: Acute renal failure (ARF) still bears a poor prognosis with mortality rates up to 70% and the ideal form of renal replacement therapy (RRT) remains controversial. The purpose of this study was to conduct a systematic review and meta-analysis of all randomized controlled trials (RCT) to examine the effect of dialysis modality (IHD: Intermittent haemodialysis; CRRT: continuous renal replacement therapy) on survival of patients with ARF and to also study the effect of each modality on dialysis dependence (DD). Methods: Using and combining two comprehensive search themes (ARF and RRT), we searched electronic databases from 1969 through September of 2007, supplemented by a manual review of abstracts from nephrology meetings and reference lists of review articles. All RCT comparing IHD with CRRT in adult patients with ARF and with explicit reporting of mortality were included. The primary outcome was the pooled estimate of the odds ratio (OR) of mortality for patients with ARF treated with CRRT versus IHD. The secondary outcome was OR of DD at time of discharge for surviving patients. Results: A total of 587 studies were identified, 554 of which were excluded on initial screening. Analysis of the nine RCT (1635 patients) showed an OR of 0.89 (0.63–1.24) for survival in patients on CRRT. Limiting the analysis to the seven RCT published after the year 2000, revealed an OR of 0.72 (0.58–0.90). The OR of all the studies before 2000 was 1.06 (95% CI 0.67–1.68), as compared with OR of 0.61 (95% CI 0.50–0.74) for studies post-2000. Four studies showed a significantly lower risk of DD among the CRRT group and none showed higher OR for DD. When analysis was limited to the RCT, the OR for DD was 1.07 (0.47–2.39), suggesting no difference in DD between the modalities. Conclusions: Similar to previously reported meta-analyses, we did not find a significant effect of CRRT on the OR of survival. The progressive reduction in the OR of survival with CRRT relative to IHD might reflect progressive improvements in IHD. The OR of DD was not affected by mode of RRT. In conclusion, compared with IHD, CRRT does not offer an advantage with regards to survival or DD in ARF. Considering its cost and potential disadvantages, it is imperative to identify the subset of patients with ARF that would potentially derive maximum benefit from CRRT. This will require large, adequately powered studies with sufficient follow-up.     

Acute renal failure in patients with acute pancreatitis: prevalence, risk factors, and outcome

A total of 267 consecutive patients presenting with acute pancreatitiswere studied restrospectively. We analysed the collected datato determine the prevalence of acute renal failure (ARF), andfactors significantly predisposing to its occurrence and outcome.The prevalence of ARF in our patients was 16%. Only 2% had isolatedARF. Seventy-three percent of patients with additional organsystem failure suffered ARF after the onset of other organ failure.The number of organ system failure was significantly greaterbefore, compared to after, the development of ARF. Using multiplelogistic regression we found that pre-existing chronic diseaseand cardiovascular and haematological failure were independentrisk factors positively related to the development of ARF, whereassystemic infection was not. Overall mortality from ARF was 81%.Chronic disease, local complications and the presence of additionalorgan system failure and their number significantly increasedmortality in ARF patients. No patients requiring renal replacementtherapy survived. ARF is a common complication of severe acute pancreatitis, butoccurs late in the disease course, and mostly preceded by otherorgan system failure. The prognosis of patients with ARF isextremely poor, indicating that more emphasis should be placedon prevention of ARF.     

Post-liver transplant acute renal failure: factors predicting development of end-stage renal disease

BACKGROUND: Acute renal failure (ARF) occurs in 5-50% of patients undergoing orthotopic liver transplantation (OLT). The aim of this study was to determine factors that might predict the development of end stage renal disease (ESRD) in patients who had ARF after OLT. METHODS: We studied all OLT recipients between 9/1/1988 through 12/31/2000. RESULTS: A total of 1602 patients underwent OLT during the study period. About 350 patients (22%) developed ARF requiring dialysis post-operatively. One hundred and twenty-three (39.8%) died within a year after OLT. Median follow up was 5.8 yr (range 1-12 yr). Forty-three patients (23%) developed ESRD over median of 3.79 yr (range 1-8 yr). Multivariate logistic regression analysis revealed creatinine levels > 1.7 mg/dL at 1 yr (p < 0.001), cyclosporine as immunosuppression (p = 0.026), and the presence of diabetes pre-OLT (p < 0.001) to be associated with the development of ESRD. The development of ESRD did not decrease patient survival (p = 0.111). ESRD patients who received subsequent kidney transplantation had significantly improved survival rates (p = 0.005). CONCLUSIONS: Serum creatinine levels at 1 yr, cyclosporine as immunosuppression, and the presence of diabetes pre-OLT are independent predictive factors for the development of ESRD. ESRD patients who received kidney transplantation had higher 10-yr survival rates when compared with patients maintained on dialysis.     

急性肝功能衰竭患者肝移植术后急性肾功能衰竭的病因分析及综合治疗

目的 分析急性肝功能衰竭(acute liver failure,ALF)患者肝移植术后肾功能衰竭的原因,评价以持续肾脏替代治疗(continuous renal replacement therapy,CRRT)为基础的综合疗法的疗效.方法 回顾性分析2001年1月至2006年6月在我院施行的412例肝移植资料,根据UNOS肝功能分级标准筛选出54例ALF患者(UNOS1和2A),其中17例移植术后出现急性肾功能衰竭(acute renal failure,ARF).在CRRT治疗基础上,进行抗排斥、抗感染、营养支持等治疗,并对患者围手术期情况、术后并发症、死亡原因及随访结果进行了分析.结果 CRRT治疗过程中无并发症发生.无ARF组围手术期死亡率为5.4%,术后并发症发生率为35.1%,1、3年生存率分别为89.2%和81.1%.ARF组围手术期死亡率为58.8%,术后并发症发生率为100%,1、3年生存率分别为41.2%和41.2%.结论 肝移植效果主要取决于肝外器官功能和术前肝功能状态.ALF患者围手术期死亡率较高,其中术前血肌酐高术后出现ARF率高,死亡率更高.以CRRT为基础的综合疗法能有效治疗ARF患者.     

Twelve years experience of acute renal failure in Taiwan

Summary: A retrospective analysis of the records of 287 patients diagnosed with acute renal failure (ARF) who were admitted between 1 January 1983 and 30 November 1994 to the emergency Service Department of the National Taiwan University Hospital, Taiwan was conducted. A total of 176 men (61.3%) and 111 women (38.7%) were surveyed. the classification of ARF by year revealed a progressive increase in case numbers. the majority (57.5%) of the patients were elderly, particularly in the years 1987-88 and 1993-94, the differences (aged compared with the young) being statistically significant. There were 176 patients (61.3%) in the pre-renal group (with evident intravascular volume depletion, haemodynamic instability or sepsis, with a urine excretion of sodium (FE_Na<1%), 43 (15%) in the renal group (urine analysis revealing protenuria, granular casts or/and tubular epithelial casts and without response to treatment of volume repletion), and 27 (9.4%) in the postrenal group (diagnosed when there were supporting image studies). Overall mortality was 63% and the pre-renal ARF patients had the poorest survival rate (25.6%). the classification of mortality rates by diagnostic category and year revealed a persistently high mortality rate. We conclude that: there are increasing patients with ARF each year; aged patients comprise the majority of cases; and the mortality rate remains high because of the high mortality rate of the pre-renal group, which was due to the presence of complicating underlying diseases and concomitant organ failure. the effects of having an ageing population were also apparent.     

Effects of different energy intakes on nitrogen balance in patients with acute renal failure: a pilot study.

BACKGROUND: Thus far, there have been no controlled studies to examine optimal levels of energy provision in critically ill patients with acute renal failure (ARF) receiving artificial nutrition. METHODS: After a 24 h nitrogen-free regimen (20% dextrose), we assigned during an open-label, AB/BA-crossover-trial, 10 ARF patients receiving both total parenteral nutrition (TPN) and renal replacement therapy (seven males; mean age 72 years, range 60-83; mean APACHE II score 27.1, range 23-34, mechanical ventilation 8/10) to a lower calorie-TPN regimen (30 kcal/kg/day) and to a higher calorie-TPN regimen (40 kcal/kg/day), each for 3 days. Nitrogen intake was 0.25 g/kg/day for both regimens. We estimated nitrogen balance, protein catabolic rate and urea generation rate by urea kinetic methods based on both timed blood samples of serum urea and direct urea quantification from dialysis fluid. RESULTS: Two patients were excluded from the analysis (due to death and serum triglycerides above 5.1 mmol/l, respectively). Compared with the lower calorie-TPN, the higher calorie-TPN regimen did not improve estimated nitrogen balance [+1.55 g/day (95% confidence interval: -0.95 to +4.05, P = 0.18)], protein catabolic rate [-0.10 g/kg/day (-0.33 to +0.14, P = 0.35)], or urea generation rate [-1.3 mg/min (-5.2 to +2.7, P = 0.46)], whereas it increased serum triglycerides [+1.36 mmol/l (+0.53 to +2.19, P = 0.007)], glucose [+1.15 mmol/l (+0.07 to +2.24, P = 0.041)], insulin need [+20.4 U/day (+8.3 to +32.6, P = 0.006)] and nutritional fluid administration [+468 ml/day (+370 to +566, P<0.001)]. CONCLUSIONS: The present study, conducted in a small group of subjects, shows that in critically ill patients with ARF on a nitrogen intake of 0.25 g/kg/day, an energy provision of 40 kcal/kg/day does not improve nitrogen balance estimates compared with a 30 kcal/kg/day intake; instead, it may increase the risk of artificial nutrition-related side-effects.     

Acute renal failure in patients with pre-existing renal dysfunction following coronary artery bypass grafting

BACKGROUND: Pre-existing renal dysfunction predisposes to acute renal failure (ARF) in patients undergoing coronary artery bypass grafting. We assessed the incidence and impact of the development of ARF in this patient population in our unit. METHODS: One-hundred and six patients had a preoperative serum creatinine of >or=0.13 mmol/L and underwent coronary artery bypass grafting in the year 2000. The incidence of ARF (as defined by a >or=50% rise in postoperative serum creatinine), hospitalization days, dialysis requirement, in-hospital and 1-year mortality, and potential risk factors for ARF were recorded. RESULTS: Of the patients recorded, 43/104 (41.35%) developed ARF following coronary artery bypass grafting. Patients with ARF stayed in hospital longer (P < 0.02). Ten out of forty-three patients required some form of dialysis and the in-hospital mortality of the renal failure group was 23% compared to 3.1% in the other group (P < 0.002). One year postoperatively, the group with renal failure had significantly worse survival (71.8% vs 98%P < 0.0001). CONCLUSION: For patients undergoing coronary artery bypass grafting, pre-existing renal dysfunction predisposes to the development of ARF, this is associated with prolonged hospitalization and increased mortality.     

Outcome in critically ill medical patients treated with renal replacement therapy for acute renal failure: comparison between patients with and those without haematological malignancies.

BACKGROUND: Starting renal replacement therapy (RRT) for acute renal failure in critically ill patients with haematological malignancies is controversial because of the poor outcome and high costs. The aim of this study was to compare the outcome between critically ill medical patients with and without haematological malignancies who received RRT for acute renal failure. METHODS: We retrospectively collected data on all consecutive patients who received RRT for acute renal failure at the Medical Intensive Care Unit (ICU) of a University Hospital between 1997 and 2002, and assessed the impact of the presence of a haematological malignancy on the survival within 6 months after ICU admission by Cox proportional hazard models. RESULTS: Fifty of the 222 (22.5%) consecutive patients with haematological malignancies admitted to the ICU over the study period received RRT for acute renal failure compared with 248 of the 4293 (5.8%) patients without haematological malignancies (P<0.001). Among patients who received RRT, those with haematological malignancies had higher crude ICU (79.6 vs 55.7%, P=0.002) and in-hospital (83.7 vs 66.1%, P=0.016) mortality rates, and a higher mortality at 6 months (86 vs 72%, P=0.018) by Kaplan-Meier estimates compared with those without haematological malignancies. However, after adjustment for the severity of illness and the duration of hospitalization before ICU admission, haematological malignancy by itself was no longer associated with a higher risk of death (hazard ratio 1.04; 95% confidence interval, 0.73-1.54, P=0.78). CONCLUSIONS: Medical ICU patients with haematological malignancies have a higher rate of occurrence of acute renal failure treated with RRT and a higher mortality, compared with those without haematological malignancies. However, the presence of a haematological malignancy by itself is not a reason to withhold RRT in medical ICU patients with acute renal failure.     

Pharmacokinetics of ciprofloxacin and vancomycin in patients with acute renal failure treated by continuous haemodialysis.

To determine appropriate doses of ciprofloxacin and vancomycin for septic patients with acute renal failure (ARF) treated by continuous arteriovenous and venovenous haemodialysis, (CAVHD/CVVHD), we performed pharmacokinetic studies in patients receiving these antibiotics. All patients were treated by CAVHD/CVVHD using Hospal AN69S 0.43 m2 filters and Fresenius 1.5% peritoneal dialysis fluid at dialysate flow rates (Qd) of 1 and 2 l/h. Patients received ciprofloxacin 200 mg i.v. 12-hourly (n = 6) or 8-hourly (n = 5); vancomycin 1 g i.v. was administered to 10 patients approximately every 48 h to maintain therapeutic plasma levels. For ciprofloxacin, volume of distribution (Vdarea) was 136.5 +/- 9.81, terminal elimination half-life (t1/2) 6.4 +/- 0.8 h, and total body clearance (TBC) 264.3 +/- 22.9 ml/min (mean +/- SEM). Mean sieving coefficient (S/C) was 0.76 +/- 0.05 and filter clearances at Qd 1 and 2 l/h were 16.2 +/- 1.9 and 19.9 +/- 1.1 ml/min respectively. For vancomycin, Vdarea was 60.7 +/- 5.11, t1/2 24.7 +/- 2.6 h and TBC 31.0 +/- 4.6 ml/min. Mean S/C was 0.66 +/- 0.08 and filter clearances at Qd 1 and 2 l/h 12.1 +/- 2.0 and 16.6 +/- 2.0 ml/min. These data suggest that patients with ARF treated by CAVHD/CVVHD should be given ciprofloxacin 200 mg i.v. 8-12-hourly and vancomycin every 48 h.     

Outcome in severe acute renal failure associated with malaria.

BACKGROUND: Malaria, a common health problem in certain parts of the world, has a considerable morbidity and mortality. This study reports its occurrence with a serious complication, acute renal failure (ARF), at a Third World tertiary care centre. METHODS: All registered patients with ARF who had history and clinical findings suggestive of malaria and had malarial parasites on peripheral blood smears were included in this study. The data on their modes of presentation, management and outcome have been analysed. RESULTS: Between January 1990 and December 1999, a total of 2098 patients with ARF were seen at the centre. Of these, 124 (5.9%) developed ARF due to malaria (falciparum in 121 and vivax in three). The male:female ratio was 4:1 and 84 (68%) patients were oligo- or anuric on presentation. Mean serum creatinine on admission was 9.43 +/- 5.39 mg/dl and 99 (79.8%) patients required renal replacement therapy. Of the cohort, 32 (25.8%) died, most within 48 h of admission. Age, oliguria, central nervous system involvement and presence of disseminated intravascular coagulopathy emerged as bad prognostic factors in simple univariate analysis. Of the survivors, 77 (62%) had complete recovery of renal function, while 15 (12%) were progressing towards recovery when lost to follow-up. The number of dialysis sessions did not differ significantly between the oliguric and non-oliguric groups. CONCLUSIONS: In patients who do not succumb early to ARF of severe malaria, treatment with antimalarials and dialysis brings about recovery of renal function.     

Cause of death in acute renal failure.

The cause of 636 deaths during acute renal failure (ARF) occurring between 1956 and 1989 were analysed. Deaths due to haemorrhage and to non-recovery of renal function have declined but cardiovascular deaths and withdrawal of active treatment have increased. The causes of death varied with the clinical situation in which ARF arose. The most important factor contributing to death was the underlying cause of ARF. 67% deaths due to sepsis resulted from infection present at the time of development of ARF. Deaths due to secondary complications have declined, indicating that the precipitating causes of ARF are the main determinant of overall mortality.     

Kinetics of carbamylated haemoglobin in acute renal failure.

BACKGROUND: Carbamylation of proteins by isocyanic acid, the reactive form of cyanate derived from urea, is increased in uraemia and may contribute to uraemic toxicity. Kinetics of carbamylation that may reflect uraemic toxicity is not clearly defined in acute renal failure (ARF). METHODS: Twenty-eight patients with ARF and 13 with chronic renal failure (CRF) were included in the study in order to determine changes in carbamylated haemoglobin concentration (CarHb) in ARF. The usefulness of this parameter for differentiating ARF from CRF was also investigated. CarHb was measured by high-performance liquid chromatography after acid hydrolysis. RESULTS: Mean CarHb level (expressed as microg carbamyl valine per gram (CV/g) Hb) was significantly higher in ARF (54.3+/-5.2) than in normal subjects (31.6+/-1.3). On admission, CarHb level was correlated with duration of ARF prior to hospitalization in the intensive care unit (r(2)=0.723, P<0.001). CarHb was significantly higher at recovery in the subgroup of patients requiring haemodialysis than in the subgroup not requiring haemodialysis (82. 4+/-11.3 vs 46.7+/-5.2, P<0.01). Similarly dialysis patients lost more weight (8.6+/-1.4 vs 2.7+/-0.5 kg, P<0.005) and had higher averaged blood urea levels in the 20 days prior to recovery (17. 6+/-1.9 vs 11.3+/-1.8 mol/l, P<0.05). After recovery, CarHb level decreased at a rate of 0.219 microg CV/g Hb per day in patients with reversible renal insufficiency. CarHb concentration was higher in patients with CRF. A cut-off CarHb value of 100 microg CV/g Hb had a sensitivity of 94% and a positive predictive value of 94% for differentiating ARF from CRF. CONCLUSIONS: Kinetics of CarHb showed a near normal red blood cell life span in ARF. Changes in CarHb enabled, with a good sensitivity, the distinction to be made between patients who recovered from ARF and those with sustained renal impairment, whether due to prior CRF or resulting from parenchymal sequelae. Measurement of CarHb is valuable at clinical presentation of ARF in patients with an unknown medical history of renal disease.     

Olmesartan associated with acute renal failure in a patient with bilateral renal artery stenosis

In patients with renal artery stenosis (RAS), the inhibition of renin-angiotensin-aldosterone system can cause deterioration of renal function. Here we present a 75-year-old man who developed acute renal failure after olmesartan treatment. Following discontinuation of olmesartan, his renal functions normalized. His renal Doppler ultrasonography and renal angiography showed findings consistent with bilateral RAS. In this case, unlike those previously reported, renal failure developed with olmesartan for the first time and after only a single dose, which is thought to be a new, safe, and tolerable antihypertensive agent. This is a well-defined effect of angiotensin-converting enzyme inhibitors, in patients with RAS. Also with the increasing use of angiotensin II receptor blockers (ARBs), renal failure associated with ARBs in patients with RAS is rising. The use of olmesartan also requires caution and close follow-up of renal functions for patients who have risk factors.     

Risk factors of acute renal injury in patients with acute left heart failure

Objectives To investigate the risk factors of acute renal injury (acute kidney injury) in patients with acute left heart failure. Methods Clinical data of 188 patients with acute left heart failure who were admitted to our hospital were retrospectively analyzed. Logistic regression analysis was used to assess the risk factors for AKI. Results Among 188 patients with acute left heart failure, incidence of acute kidney injury was 33.51%. Univariate and Multivariable logistic regression analyses showed that the independent predictors of acute kidney injury were lower baseline eGFR (OR=4.294, P＜0.001) and anemia (OR=3.573, P=0.006). Conclusions The incidence of acute left heart failure complicated with AKI was high. Basic state of renal function and anemia were the independent risk factors for AKI.