The change in renal replacement therapy on acute renal failure in a general intensive care unit in a university hospital and its clinical efficacy: a Japanese experience

The aim of our study was to examine renal replacement therapies (RRT) that have been used for acute renal failure (ARF) in our intensive care unit (ICU) patients and to compare their outcomes. Sixteen patients who underwent intermittent hemodialysis (IHD), 14 patients who underwent continuous hemofiltration (CHF) in combination with IHD (CHF + IHD), and 38 patients who underwent continuous hemodiafiltration (CHDF) were evaluated. Regarding the effects of blood purification on hemodynamics and renal function, the percentage increase in blood pressure and percent rapid increase in urinary output were the greatest in the CHDF group. The hourly urinary output after the start of initial blood purification increased only in the CHDF group. The survival rate was significantly higher in the CHDF group. These results suggest that CHDF should be the first-line therapy for patients with ARF and that we are moving in the right direction regarding the application of RRT to treat ARF in ICU patients.     

Renal replacement strategies in the ICU

Acute renal failure (ARF) with the concomitant need for renal replacement therapy (RRT) is a common complication of critical care medicine that is still associated with high mortality. Different RRT strategies, like intermittent hemodialysis, continuous venovenous hemofiltration, or hybrid forms that combine the advantages of both techniques, are available and will be discussed in this article. Since a general survival benefit has not been demonstrated for either method, it is the task of the nephrologist or intensivist to choose the RRT strategy that is most advantageous for each individual patient. The underlying disease, its severity and stage, the etiology of ARF, the clinical and hemodynamic status of the patient, the resources available, and the different costs of therapy may all influence the choice of the RRT strategy. ARF, with its risk of uremic complications, represents an independent risk factor for outcome in critically ill patients. In addition, the early initiation of RRT with adequate doses is associated with improved survival. Therefore, the "undertreatment" of ARF should be avoided, and higher RRT doses than those in patients with chronic renal insufficiency, independent of whether convective or diffusive methods are used, are indicated in critically ill patients. However, clear guidelines on the dose of RRT and the timing of initiation are still lacking. In particular, it remains unclear whether hemodynamically unstable patients with septic shock benefit from early RRT initiation and the use of increased RRT doses, and whether RRT can lead to a clinically relevant removal of inflammatory mediators.     

A prospective, multicenter study of the epidemiology, management, and outcome of severe acute renal failure in a "closed" ICU system

The safety and effectiveness of "closed" intensive care units (ICUs) are highly controversial. The epidemiology and outcome of acute renal failure (ARF) requiring replacement therapy (severe ARF) within a "closed" ICU system are unknown. Accordingly, we performed a prospective 3-mo multicenter observational study of all Nephrology Units and ICUs in the State of Victoria (all "closed" ICUs), Australia, and focused on the epidemiology, treatment, and outcome of patients with severe ARF. We collected demographic, clinical, and outcome data using standardized case report forms. Nineteen ward patients and 116 adult ICU patients had severe ARF (13.4 cases/100, 000 adults/yr). Among the ICU patients with severe ARF, 37 had impaired baseline renal function, 91 needed ventilation, and 95 needed vasoactive drugs. Intensivists controlled patient care in all cases. Continuous renal replacement therapy (CRRT) was used in 111 of the ICU patients. Nephrological opinion was sought in only 30 cases. Predicted mortality was 59.6%. Actual mortality was 49.2%. Only 11 ICU survivors were dialysis dependent at hospital discharge. In the state of Victoria, Australia, intensivists manage severe ARF within a "closed" ICU system. Renal replacement is typically continuous and outcomes compare favorably with those predicted by illness severity scores. Our findings support the safety and efficacy of a "closed" ICU model of care.     

合并肾功能衰竭的肝移植患者接受肾脏替代治疗的价值

目的 回顾性分析合并急性肾功能衰竭的肝移植受体移植术前的危险因素,并探讨肾脏替代治疗(RRT)作为其移植前过渡治疗措施的价值. 方法收集2001年1月-2008年1月在卫生部移植医学工程技术研究中心由于急性肾功能衰竭而接受RRT的肝移植受体患者,依据不同预后对肝移植受体的临床特征进行分组对比分析;按接受不同RRT种类对肝移植受体的临床特征进行分组对比分析.用逻辑回归法分析能预测合并肾功能衰竭肝移植受体病死率的指标.对数据进行f检验、χ2检验、Logistic回归分析.结果 在接受RRT的患者中,有31.25%的患者因为肝移植而生存或者出院,68.75%的患者在等待移植期间死亡.死亡组患者与移植组相比,有更高的多器官功能障碍评分(4.98±2.32与4.45±2.02,P=0.008)、更低的平均动脉压[(56.5±7.1)mm Hg与(65.4±12.9)mm HgP=0.040;1 mm Hg=0.133 kPa].RRT的平均治疗天数在连续性肾脏替代治疗组和间歇血液透析组之间的差异没有统计学意义.与间歇血液透析组相比,连续性肾脏替代治疗组有更高的多器官功能障碍评分(4.82±2.12与3.45±1.91,P=0.040)、更低的平均动脉压[(56.0±14.2)mm Hg与(68.5±15.3)mm Hg,P=0.002]、更低的血清肌酐浓度[(320.12±185.15)μmol/L与(420.55±158.32)μmol/L,JP=0.008].肾功能衰竭受体术前平均动脉压越低,则死亡风险越高. 结论对患有急性肾功能衰竭的肝移植受体应用RRT是可取的.尽管病死率仍高,但可使部分患者得以肝移植而生存.     

Dialyse auf der Intensivstation

Acute kidney injury in the ICU is increasing dramatically worldwide; thus, the need for renal replacement therapy (RRT) is also increasing. There are mainly three different means of extracorporeal treatment: intermittent hemodialysis, continuous renal replacement therapy, and extended dialysis. Because extended dialysis combines efficient detoxification with a favorable cardiovascular tolerability profile, even in critically ill patients, it is increasingly being utilized. The technical progress in RRT machines leveled off during recent years, with automated citrate anticoagulation being the last meaningful technical advancement. Unresolved issues include the following questions: when do we start RRT and how do we measure its dose. Several recent randomized trials have shown that the relationship between dose of RRT and survival is not linear, thus, leaving it to the discretion of the nephrologist and/or intensivist to choose the mean of RRT and its dose in a complex therapeutic concept for the critically ill patient. Highly efficient means of RRT eliminate potentially life-saving drugs, like antibiotics, to a larger extent than one or two decades ago. As sepsis is responsible for the onset of acute renal failure in more than half of the patients, careful adjustment (i.e., increase) of the dose of antibiotics is crucial to avoid under-dosing of these drugs.     

End-stage renal failure patients requiring renal replacement therapy in the intensive care unit: incidence,clinical features,and outcome

AIMS: To study incidence, clinical features, and outcome of critically ill patients with end-stage renal failure (ESRF) requiring renal replacement therapy (RRT) in the intensive care unit (ICU) and to test the validity of severity scoring systems for these patients. METHODS: Data for ESRF patients treated with RRT were collected from 81 Australian adult ICUs providing RRT. They were compared with matched controls with acute renal failure. RESULTS: Thirty-eight ESRF patients received RRT in the ICU over 3 months. The mean APACHE II score was 21.8 (predicted mortality: 37%) and the SAPS II score 44.7 (predicted mortality: 37%). The hospital mortality was 34%. Receiver operating characteristic curves showed good discrimination ability for hospital mortality for these two scores (AUC: 0.81 for APACHE II and 0.84 for SAPS II). Using admission diagnosis and SAPS II scores, 32 ESRF patients treated with continuous RRT (CRRT) were matched to 32 acute renal failure patients also treated with CRRT. ICU mortality (22 vs. 38%) and hospital mortality (38 vs. 38%) were comparable between the two groups. CONCLUSIONS: ESRF patients requiring RRT in the ICU were relatively frequent. Severity scores could be used to predict the hospital outcome for these patients. Their mortality, when treated with CRRT, was similar to that of diagnosis- and severity-score-matched patients with acute renal failure.     

Pharmacokinetics of antibiotics in continuous renal replacement therapies (CRRT)

In the critically ill patient, acute kidney injury (AKI) is frequently associated with infective complications requiring appropriate antimicrobial treatment. AKI and multiple organ dysfunction syndrome can affect the pharmacokinetic parameters of many drugs. Furthermore, the start of renal replacement therapy (RRT) is an additional variable to be taken into consideration to avoid inappropriate antimicrobial therapy. Continuous renal replacement therapies (CRRT) are widely adopted in the intensive care unit (ICU) and antibiotics that are significantly eliminated by the kidney are likely to be removed during RRT. Generally, drug-dosing adjustments are required if the extracorporeal clearance accounts for more than 25-30% of the total body clearance. The molecular weight cutoffs of the more widely used membranes are much higher than the molecular weight of most drugs. Therefore, molecular size will not be a limitation for the removal of the unbound fraction of the antibiotics most commonly used in ICU patients. However, CRRTs are still not standardized and the impact of RRT on plasma drug concentrations can be substantially different depending on the CRRT modality (diffusive, convective or both), membrane characteristics and delivered dialysis dose. In any case, drug-dosing adjustments should be based on the knowledge of the pharmacokinetic and pharmacodynamic properties of the different classes of antimicrobials, taking into account that high extracorporeal clearances could lead to drug underexposure in clinical conditions where appropriate antibiotic treatment is essential.     

Akutes Nierenversagen bei Sepsis

Acute renal failure has a major impact on the prognosis of septic patients. Changes in the understanding of the pathophysiology and more precise definitions of acute kidney injury (AKI) are expected to lead to improved therapeutic options in the future. At present early recognition, early targeted fluid therapy with crystalloids and vasopressors, as well as the avoidance of nephrotoxic substances are the key measures in prevention and therapy of AKI. If renal replacement therapy (RRT) becomes necessary it should be started promptly following ICU admission. Different modalities of RRT with various advantages and disadvantages are available and should be applied differentially. While a sufficient dose of RRT is important, new studies suggest that further dose increases do not lead to improved outcome.     

The importance of early referral for the treatment of chronic kidney disease: a Danish nationwide cohort study

ABSTRACT: BACKGROUND: Many patients with advanced chronic kidney disease are referred late to renal units. This is associated with negative aspects. The purpose of the present study was to characterize late versus early referrals for renal replacement therapy including their renal disease, health care contacts and medical treatment before renal replacement therapy (RRT) and the consequences for RRT modality and mortality. METHODS: Nationwide cohort study including 4495 RRT patients identified in the Danish Nephrology Registry 1999--2006. The cohort was followed to end 2007 by linkage to other national registries. Late referral: follow-up <=16 weeks in renal unit before RRT start. Cox proportional hazards models were used to estimate the relative risk of mortality or waiting list status within 365 days in late referrals versus early referrals. RESULTS: A total of 1727 (38%) incident RRT patients were referred late. Among these, 72% were treated in non-nephrology hospital departments and 91% in general practice 2 years to 16 weeks before RRT start. Fewer late referrals received recommended pre-RRT treatment as judged by renin-angiotensin-system blockade: 32% versus 57% or the D-vitamin analogue alfacalcidol: 5% versus 30% (P < .001). Primary RRT modality was peritoneal dialysis: 18% in late versus 32% in early referrals (P < .001), 7% versus 30%, respectively, had an arteriovenous dialysis-fistula (P < .001) and 0.2% versus 6% were on the waiting-list for renal transplantation (P < .001) before RRT start. One-year-mortality was higher in late referrals: hazard ratio 1.55 (CI 95% 1.35--1.78). In a subgroup, 30% (CI 95% 25--35%) late and 9% (CI 95% 6--12%) early referrals had plasma creatinine <=150% of upper reference limit within 1 to 2 years before RRT start (P < .001). CONCLUSIONS: Late nephrology referrals were well-known to the healthcare system before referral for RRT start and more often had near normal plasma creatinine levels within 2 years before RRT start. They infrequently received available treatment or optimal first RRT modality. An increased effort to identify these patients in the healthcare system in time for proper pre-dialysis care including preparation for RRT is needed.     

RIFLE-based data collection/management system applied to a prospective cohort multicenter Italian study on the epidemiology of acute kidney injury in the intensive care unit

The epidemiology of acute kidney injury (AKI) has been difficult to explore in the past, due to different definitions across various studies. Nevertheless, this is a very important topic today in light of the high morbidity and mortality of critically ill patients presenting renal dysfunction during their stay in the intensive care unit (ICU). The case mix has changed over the years, and AKI is a common problem in critically ill patients often requiring renal replacement therapy (RRT). The RIFLE and AKIN initiatives have provided a unifying definition for AKI, making possible large retrospective studies in different countries. The present study aims at validating a unified web-based data collection and data management tool based on the most recent AKI definition/classification system. The interactive database is designed to elucidate the epidemiology of AKI in a critically ill population. As a test, we performed a prospective observational multicenter study designed to prospectively evaluate all incident admissions in ten ICUs in Italy and the relevant epidemiology of AKI. Thus, a simple user-friendly web-based data collection tool was created with the scope to serve for this study and to facilitate future multicenter collaborative efforts. We enrolled 601 consecutive incident patients into the study; 25 patients with end-stage renal disease were excluded, leaving 576 patients for analysis. The median age was 66 (IQR 53-76) years, 59.4% were male, while median Simplified Acute Physiology Score II and Acute Physiology and Chronic Health Evaluation II scores were 43 (IQR 35-54) and 18 (IQR 13-24), respectively. The most common diagnostic categories for ICU admission were: respiratory (27.4%), followed by neurologic (17%), trauma (14.4%), and cardiovascular (12.1%). Crude ICU and hospital mortality were 21.7% and median ICU length of stay was 5 (IQR 3-14) days. Of 576 patients, 246 patients (42.7%) had AKI within 24 h of ICU admission, while 133 developed new AKI later during their ICU stay. RIFLE-initial class was Risk in 205 patients (54.1%), Injury in 99 (26.1%) and Failure in 75 (19.8%). Progression of AKI to a worse RIFLE class was seen in 114 patients (30.8% of AKI patients). AKI patients were older, with higher frequency of common risk factors. 116 AKI patients (30.6%) fulfilled criteria for sepsis during their ICU stay, compared to 33 (16.7%) of non-AKI patients (p < 0.001). 48 patients (8.3%) were treated with RRT in the ICU. Patients were started on RRT a median of 2 (IQR 0-6) days after ICU admission. AKI patients were started on RRT a median of 1 (IQR 0-4) day after fulfilling criteria for AKI. Median duration of RRT was 5 (IQR 2-10) days. AKI patients had a higher crude ICU mortality (28.8 vs. 8.1%, non-AKI; p < 0.001) and longer ICU length of stay (median 7 vs. 3 days, non-AKI; p < 0.001). Crude ICU mortality and ICU length of stay increased with greater severity of AKI. 225 (59.4% of AKI patients) had complete recovery of renal function, with a serum creatinine at time of ICU discharge which was ≤120% of baseline; an additional 51 AKI patients (13.5%) had partial renal recovery, while 103 (27.2%) had not recovered renal function at the time of death or ICU discharge. The study supports the use of RIFLE as an optimal classification system to stage AKI severity. AKI is indeed a deadly complication for ICU patients, where the level of severity is correlated with mortality and length of stay. The tool developed for data collection was user-friendly and easy to implement. Some of its features, including a RIFLE class alert system, may help the treating physician to systematically collect AKI data in the ICU and possibly may guide specific decisions on the institution of RRT.     

心血管疾患伴发急性肾功能衰竭及多脏器功能衰竭的救治及预后

目的 回顾性分析心血管疾病伴发急性肾功能衰竭及多脏器功能衰竭的病因、治疗及预后。方法14例患者主要因急性心肌梗死、心肺复苏后、心脏手术后、冠状动脉造影后发生急性肾功能衰竭或多脏器功能衰竭,进行肾脏替代疗法。结果 14例患者5例存活,9例死亡,病死率64.3％;其中7例伴糖尿病者,6例死亡;急性心肌梗死后7例患者4例死亡,心脏手术后4例患者3例死亡;死亡主要与器官衰竭数目相关。结论心血管疾病伴发急性肾功能衰竭及多脏器功能衰竭经肾脏替代疗法及血流动力学监测,有助于体液平衡,稳定心血管系统,是安全有效的治疗方法。     

The challenges of providing renal replacement therapy in decompensated liver cirrhosis

Development of renal failure requiring renal replacement therapy (RRT) in the cirrhotic patient is a devastating complication. Survival without RRT is less than 10% on average at 6 months. However, it is now appreciated that all renal failure in this group of patients is not due solely to hepatorenal syndrome, and the cause of the renal failure affects the prognosis. This paper reviews the prognosis depending on cause and points out the difficulty in making the correct diagnosis. Provision of RRT is difficult in this group of patients due to hypotension and coagulopathy which is highly prevalent. Survival with RRT is still poor with only 30-60% of patients surviving to liver transplant. Provision of RRT should be offered as a bridge to patients awaiting liver transplant or those undergoing liver transplant evaluation. Provision of long-term RRT is usually not indicated in other cirrhotic patients who develop a need for RRT except as a trial to see if renal function will return. The decision between intermittent hemodialysis or continuous renal replacement therapy (CRRT) is usually based on the clinical characteristics of the patient. Neither has been demonstrated to be superior to the other, although CRRT may be better tolerated in the unstable patient. CRRT is clearly indicated in cases of fulminant hepatic failure as it does not raise intracranial pressure. Provision of intraoperative CRRT during liver transplant may be indicated to help control volume and electrolytes in those patients presenting for liver transplant with renal failure. Newer extracorporeal support systems, such as extracorporeal albumin dialysis (MARS) and fractional plasma separation and adsorption with hemodialysis (Prometheus), have recently been developed to provide both renal and liver support in this group of patients. These are still considered experimental, although the MARS system has been utilized to treat patients with hepatorenal syndrome, and is available outside the United States.     

Hemorrhagic cardiac tamponade in critically ill patients with acute renal failure

PURPOSE: The purpose of this study was to report the development, management, and follow up of tamponading uremic pericardial effusion in critically ill patients with acute renal failure. SETTING: The setting for this study was an adult, 24-bed tertiary multidisciplinary intensive care unit (ICU) of a university hospital. PATIENTS: The subjects were 5 critically ill patients with multiple organ failure including acute renal failure (ARF) that was slow to resolve. RESULTS: Renal involvement was attributed to renal hypoperfusion, sepsis and myoglobinuria. Continuous veno-venous hemofiltration (CVVH) was instituted early during hospitalization in 4 cases and lasted for 35 to 48 days; renal replacement therapy was not used in 1 case. Tamponade developed late in the course of ARF, after CVVH was discontinued in the 4 cases and was effectively managed with percutaneous pericardiocentesis under echocardiography and continuous catheter drainage of the pericardial sac for 48 to 72 hours. Hemorrhagic fluid (Hb 2.2-5.9 g/dL) with lymphocyte predominance was detected. Transient constrictive-like pericarditis findings were present in all patients after the procedure. All patients were discharged from the hospital in a good condition with normal serum and creatinine levels; 1-year follow up showed a normal echocardiogram. CONCLUSION: Awareness for the possibility of hemorrhagic pericarditis and cardiac tamponade is needed in ICU patients with ARF slow to resolve. Transient constrictive-like pericarditis may present after pericardiocentesis.     

Common places on clinical management of acute renal failure

Acute renal failure (ARF) is an abrupt decline of renal function, and acute tubular necrosis (ATN) is its more frequent expression. Recent contributions in physiopathological knowledge, specially in post-ischemic ARF, are scarcelly reflected in therapy. Morbidity and mortality due to ARF are very high, mainly in critically ill patients. Prevention and treatment of ATN are based in avoiding nephrotoxicity and renal ischemia. An adequate evaluation of renal risk factors in hospitalized patients is important. Maintaining euvolemia, effective cardiac output and adequate renal perfussion pressure are three paramount factors in ischemia prevention. The best dialytic schedule is not universally accepted. ARF replacement therapy must be flexible, tailoring techniques (IHD, SLED, CRRT) to the clinical situation of patients. There is not a consensus in dialysis dose in ARF. Nevertheless, despite a robust scientific evidence is lacking, some data suggest that a delivered minimum dose of sKtV >1 in IHD or >35 ml/kg/h in CRRT would be beneficial for patient survival.     

The role of the renal specialist nurse in prevention of renal failure

This article will investigate the care required for those with reduced renal function before renal replacement therapy (RRT) commences. Renal nurses are often involved with the technical, monitoring and evaluative aspects of RRT for those with end stage renal failure. However, many patients may experience reduced renal function many years before reaching the stage of needing RRT. Renal nurses are already involved in the preparation of patients for RRT, but are not presently exercising their specialist skills in the period before this time by contributing to the prevention of end stage renal failure (ESRF). Screening programmes carried out in various parts of the world demonstrate that many members of the population have undetected renal insufficiency, and may benefit from intervention from the nephrology team to prevent further renal dysfunction. It is for this group of patients that this article will consider the potential for the renal nurse to expand their scope of practice.     

连续肾脏替代治疗在肝移植中的应用

目的探讨连续肾脏替代治疗(CRRT)在肝移植术后急性肾功能衰竭(ARF)合并多器官功能不全(MODS)治疗中的应用价值。方法分析连续静脉静脉血液滤过(CVVH)治疗7例肝移植术后ARF、成人呼吸窘迫综合征(ARDS)、急性心衰、全身炎症反应综合征(SIRS)等患者。3例合并ARDS患者同时进行呼吸机辅助呼吸治疗。结果4例治愈,另3例ARF合并MODS患者死亡。经CVVH治疗后,患者血清中的肌酐、尿素氮、血钾较治疗前降低(P<0.05),凝血酶原时间变化无意义。结论CVVH能有效控制氮质血症和高血钾等高分解状态,而不影响凝血功能。早期应用可以改善肝移植术后ARF、ARDS、充血性心力衰竭、SIRS等MODS患者的预后。     

Renal supportive care and palliative care: revision and proposal in kidney replacement therapy

Patients with chronic kidney disease may receive sustained renal supportive care and renal palliative care (RPC) starting with the diagnosis of the disease, throughout the various stages of renal replacement therapy (RRT), the cessation of the RRT, and in the decision of whether to provide conservative treatment or non-initiation of RRT. This article reviews the literature on the development of renal palliative care and proposed RPC models. We describe the progression of disease in organ failure, which is very different from other areas of palliative care (PC). We describe important components of resident nephrology training in PC. We discuss the management of pain and symptom control, as well as communication skills and other psychological and ethical aspects in the renal patient. We conclude that in chronic renal patients, a palliative care approach can provide a positive impact on the quality of life of patients and their families, as well as optimizing the complex treatment of the renal patient.