Rifle classification for predicting in-hospital mortality in critically ill sepsis patients. Shock. 2009;31:139-145. [PMID: 18520698 DOI: 10.1097/shk.0b013e31817d419e]

Effect of renal replacement therapy modalities on renal recovery and mortality for acute kidney injury: A PRISMA-compliant systematic review and meta-analysis

Previous investigations showed inconsistent results for comparison in renal recovery, in-hospital, and in-intensive care unit (ICU) mortalities between acute kidney injury (AKI) patients treated with continuous renal replacement therapy (CRRT) and some kinds of intermittent renal replacement therapies (IRRTs). We systematically searched for articles published in the databases (PubMed, Web of Science, EMBASE, Medline, and Google Scholar) until June 2019. We made all statistical analysis using STATA 12.0 software. In the present meta-analysis, relative risks with 95% confidence intervals were calculated for binary outcomes (renal recovery status or mortality). The present study indicated no significant differences in renal recovery, in-hospital mortality, and in-ICU mortality between AKI patients given CRRT and those given sustained low-efficiency dialysis (SLED). Additionally, the study showed no significant difference in in-hospital mortality between AKI patients given CRRT and those given intermittent hemodialysis (IHD), whereas elevated in-ICU mortality was detected in AKI patients given CRRT, compared to those given IHD. The three modalities (CRRT, IHD, and SLED) have their own advantages and disadvantages. More rigorous trials design with large cohort should be made to explore the differences in renal recovery, in-hospital, and in-ICU mortalities between different kinds of RRTs.

Renal replacement therapy: a practical update

Acute kidney injury (AKI) is defined as an abrupt decrease in kidney function, with the most severe form requiring some method of renal replacement therapy (RRT). The use of RRT is required in 5-10% of critically ill patients who develop severe AKI. Renal replacement therapy can be provided as either intermittent hemodialysis or one of the various modes of continuous renal replacement therapy (CRRT), with CRRT potentially conferring an advantage with respect to renal recovery and dialysis independence. There is no difference in mortality when comparing low (< 25 mL·kg^-1·hr^-1) vs high (> 40 mL·kg^-1·hr^-1) RRT dosing. Continuous renal replacement therapy may be run in different modes of increasing complexity depending on a given patient's clinical needs. Regional citrate anticoagulation is recommended as the therapy of choice for the majority of critically ill patients requiring CRRT.

[Epidemiology of acute renal failure]

The acute renal failure is common in the hospitalized patients with the incidence is increasing. This results from the aging of the population and the widespread use of nephrotoxic therapies or diagnostic techniques. The acute renal failure is associated with an increased length of stay in hospital and the short and long-term mortality. The most common histological injury is the acute tubular necrosis. Although the most of acute renal failure is recovering, recent works have shown that there is a strong association between an acute renal failure and the increased risk of developing a chronic kidney disease.

Aminoglycoside-associated acute kidney injury in elderly patients with and without shock

OBJECTIVES

Multiresistant Gram-negative pathogens pose major healthcare concerns with a limited therapeutic armamentarium. Aminoglycosides (AG) are under-utilized due to nephrotoxicity. We aimed to evaluate AG-associated acute kidney injury (AG-AKI) in elderly inpatients, with and without shock.

METHODS

We examined the incidence and predictors of AG-AKI by KDIGO criteria and extended renal dysfunction (ERD) in patients aged >60 years. ERD represented a composite of hospital mortality or absence of renal recovery over 6 months following AG-AKI.

RESULTS

Two hundred and seventy-eight patients (aged 74 ± 8 years) were studied; 43% and 19% received >7 and >10 days of AG therapy, respectively, and 70% gentamicin (versus amikacin). Thirteen per cent had shock and 17% developed AG-AKI. Comparing all patients with shock versus no shock, AG-AKI developed in 33% versus 14%, respectively (P = 0.005); correspondingly among 47 patients with AG-AKI, more with shock had stage 2/3 AKI (92% versus 43%) and dialysis (50% versus 9%) (P < 0.01), but more had other strong AKI confounders than AG therapy alone (83% versus 40%, P = 0.02). Multivariate analyses identified mechanical ventilation, frusemide administration and AG therapy >10 days as predictors of AG-AKI (P < 0.05), whereas shock, pneumonia and frusemide administration predicted more severe stage 2/3 AG-AKI (P < 0.05). Hospital mortality was 30% versus 7% with AG-AKI versus none (P < 0.001). Twenty-three of 211 (11%) patients with extended analysis had ERD, with 47% experiencing renal recovery following AG-AKI. Mechanical ventilation and contrast administration during index hospitalization predicted ERD (P < 0.05).

CONCLUSIONS

AG-AKI is common in the elderly, with a significant risk of ERD, but the cause and severity are greatly influenced by critical illness and shock, more so than AG therapy alone.

Identification and predicting short-term prognosis of early cardiorenal syndrome type 1: KDIGO is superior to RIFLE or AKIN

Objective

Acute kidney injury (AKI) in patients hospitalized for acute heart failure (AHF) is usually type 1 of the cardiorenal syndrome (CRS) and has been associated with increased morbidity and mortality. Early recognition of AKI is critical. This study was to determine if the new KDIGO criteria (Kidney Disease: Improving Global Outcomes) for identification and short-term prognosis of early CRS type 1 was superior to the previous RIFLE and AKIN criteria.

Methods

The association between AKI diagnosed by KDIGO but not by RIFLE or AKIN and in-hospital mortality was retrospectively evaluated in 1005 Chinese adult patients with AHF between July 2008 and May 2012. AKI was defined as RIFLE, AKIN and KDIGO criteria, respectively. Cox regression was used for multivariate analysis of in-hospital mortality.

Results

Within 7 days on admission, the incidence of CRS type 1 was 38.9% by KDIGO criteria, 34.7% by AKIN, and 32.1% by RIFLE. A total of 110 (10.9%) cases were additional diagnosed by KDIGO criteria but not by RIFLE or AKIN. 89.1% of them were in Stage 1 (AKIN) or Stage Risk (RIFLE). They accounted for 18.4% (25 cases) of the overall death. After adjustment, this proportion remained an independent risk factor for in-hospital mortality [odds ratios (OR)3.24, 95% confidence interval(95%CI) 1.97–5.35]. Kaplan-Meier curve showed AKI patients by RIFLE, AKIN, KDIGO and [K(+)R(−)+K(+)A(−)] had lower hospital survival than non-AKI patients (Log Rank P<0.001).

Conclusion

KDIGO criteria identified significantly more CRS type 1 episodes than RIFLE or AKIN. AKI missed diagnosed by RIFLE or AKIN criteria was an independent risk factor for in-hospital mortality, indicating the new KDIGO criteria was superior to RIFLE and AKIN in predicting short-term outcomes in early CRS type 1.

Correlation of lactate/albumin ratio level to organ failure and mortality in severe sepsis and septic shock

BACKGROUND

This study examines the clinical utility of the increased lactate/albumin ratio as an indicator of multiple-organ dysfunction syndrome (MODS) and mortality in severe sepsis and septic shock.

METHODS

We designed a prospective cohort study in an intensive care unit, and 54 patients with severe sepsis or septic shock were included. Data were used to determine a relationship between lactate/albumin ratio and the development of MODS and mortality. These associations were determined by the Mann-Whitney test, multiple logistic regression, plotting the receiver operating characteristic curve and Spearman test.

RESULTS

Lactate/albumin ratio level was higher in MODS patients on day 1 (median [interquartile range, or IQR], 2.295 [1.818-3.065]; n = 30, P < .0001) than in those without (median [IQR], 1.550 (1.428-1.685); n = 24), and on day 2, (median [IQR], 1.810 [1.377-2.448]; n = 26, P = .0022) it was higher than in those without (median [IQR], 1.172 (1.129-1.382); n = 23) on day 2. We found that lactate/albumin ratio was an independent predictor of the development of MODS (odds ratio, 5.5; P = .033; 95% confidence interval, 1.1-26.1) during intensive care unit stay. The area under the receiver operating characteristic curve showed that lactate/albumin ratio could predict MODS (0.8458) and mortality (0.8449). Furthermore, the higher the Acute Physiology and Chronic Health Evaluation II score, the more lactate/albumin ratio was discovered on day 1 (r = 0.5315, P < .0001) and day 2 (r = 0.5408, P < .0001), whereas the lower partial pressure of oxygen in arterial blood/fraction of inspired oxygen ratio, the more lactate/albumin ratio was illustrated on day 1 (r = -0.5143, P < .0001) and day 2 (r = -0.5420, P < .0001).

CONCLUSIONS

Increased lactate/albumin ratio correlates with the development of MODS and mortality in patients with severe sepsis and septic shock.

Serum estradiol levels predict survival and acute kidney injury in patients with septic shock--a prospective study

Sex hormones have diverse immunomodulatory effects that may be involved in the pathogenesis of sepsis. However, the roles of serum sex hormones in predicting outcomes and the severity of organ dysfunction, especially acute kidney injury (AKI), in septic shock patients remains controversial. We prospectively enrolled 107 clinically diagnosed pneumonia-related septic shock patients and serum sex hormone levels were measured on the day of shock onset. The aim of the present study was to investigate the predictive values of serum sex hormones levels for 28-day mortality and organs dysfunction, especially AKI. Compared with survivors, serum levels of progesterone (p<0.001) and estradiol (p<0.001) were significantly elevated in non-survivors. In multivariate Cox regression analysis, serum level of estradiol >40 pg/mL (p = 0.047) and APACHE II score ≥25 (p = <0.001) were found to be independent predictors of day 28 mortality. Inclusion of estradiol levels further enhanced the ability of APACHE II scores to predict survival in patients with high mortality risk. A serum level of estradiol >40 pg/mL was also an independent predictor of concomitant AKI (p = 0.002) and correlated well with severity of renal dysfunction using RIFLE classification. Elevated serum estradiol levels also predicted the development of new AKI within 28 days of shock onset (p = 0.013). In conclusion, serum estradiol levels appear to have value in predicting 28-day mortality in septic shock patients. Increased serum estradiol levels are associated with higher severity of concomitant AKI and predict development of new AKI.

Validation of the Kidney Disease Improving Global Outcomes criteria for AKI and comparison of three criteria in hospitalized patients

BACKGROUND AND OBJECTIVES

AKI is a major clinical problem and predictor of outcome in hospitalized patients. In 2013, the Kidney Disease: Improving Global Outcomes (KDIGO) group published the third consensus AKI definition and classification system after the Risk, Injury, Failure, Loss of Kidney Function, and End-Stage Kidney Disease (RIFLE) and the Acute Kidney Injury Network (AKIN) working group systems. It is unclear which system achieves optimal prognostication in hospital patients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A retrospective observational study using hospital laboratory, admission, and discharge databases was performed that included adult patients admitted to a teaching hospital in Tokyo, Japan between April 1, 2008, and October 31, 2011. AKI occurring during each hospital stay was identified, and discriminative ability of each AKI classification system based on serum creatinine for the prediction of hospital mortality was assessed. The receiver operating characteristic curve, a graphical measure of test performance, and the area under the curve were used to evaluate how classifications preformed on the study population.

RESULTS

In total, 49,518 admissions were studied, of which 11.0% were diagnosed with RIFLE criteria and 11.6% were diagnosed with KDIGO criteria, but only 4.8% were diagnosed with AKIN criteria. Overall hospital mortality was 3.0%. AKI staging and hospital mortality were closely correlated in all systems. Discrimination for hospital mortality was similar for RIFLE and KDIGO criteria (area under the curve=0.77 versus 0.78; P=0.02), whereas AKIN discrimination was inferior (area under the curve=0.69 versus RIFLE [P<0.001] versus KDIGO [P<0.001]).

CONCLUSION

Among hospital patients, KDIGO and RIFLE criteria achieved similar discrimination, but the discrimination of AKIN was inferior.

Serum interleukin-18 at commencement of renal replacement therapy predicts short-term prognosis in critically ill patients with acute kidney injury

Background

Acute kidney injury (AKI) requiring renal replacement therapy (RRT) in critically ill patients results in a high hospital mortality. Outcome prediction in this selected high-risk collective is challenging due to the lack of appropriate biomarkers. The aim of this study was to identify outcome-specific biomarkers in this patient population.

Methodology/Principal Findings

Serum samples were collected from 101 critically ill patients with AKI at the initiation of RRT in intensive care units (ICUs) of a tertiary care university hospital between August 2008 and March 2011. Measurements of serum levels of cystatin C (CysC), neutrophil gelatinase-associated lipocalin, and interleukin-18 (IL-18) were performed. The primary outcome measure was hospital mortality. The observed overall mortality rate was 56.4% (57/101). Multiple logistic regression analysis indicated that the serum IL-18 and CysC concentrations and Acute Physiology and Chronic Health Evaluation III (ACPACHE III) scores determined on the first day of RRT were independent predictors of hospital mortality. The APACHE III score had the best discriminatory power (0.872±0.041, p<0.001), whereas serum IL-18 had the best Youden index (0.65) and the highest correctness of prediction (83%). Cumulative survival rates at 6-month follow-up following hospital discharge differed significantly (p<0.001) for serum IL-18 <1786 pg/ml vs. ≥1786 pg/ml in these critically ill patients.

Conclusions

In this study, we confirmed the grave prognosis for critically ill patients at the commencement of RRT and found a strong correlation between serum IL-18 and the hospital mortality of ICU patients with dialysis-dependent AKI. In addition, we demonstrated that the APACHE III score has the best discriminative power for predicting hospital mortality in these critically ill patients.

Acute kidney injury in intensive care units according to RIFLE classification: a population-based study

INTRODUCTION

Recent studies of the incidence of acute kidney injury (AKI) are largely based on estimated baseline serum creatinine values. The aim of this study was to more accurately determine the incidence of AKI using the RIFLE criteria for intensive care unit (ICU) patients of a whole population.

MATERIALS AND METHODS

All adult patients admitted to the ICUs of Landspitali - The National University Hospital of Iceland in 2007 (n = 1026) were studied with meticulous search for baseline creatinine. The underlying risk factors and contributing causes for AKI were defined, and survival and ratio of end-stage renal failure evaluated.

RESULTS

A measured baseline creatinine value was found for all but two patients with AKI. The incidence of AKI according to RIFLE criteria was 21.7% [95% confidence interval (CI): 19.0-24.1%], with 7.1% (95 CI: 5.6-8.9%), 6.8% (95 CI: 5.3-8.5%) and 7.8% (95 CI: 6.2-9.6%) in the risk, injury and failure subgroups. Using estimated baseline creatinine overestimated the incidence of AKI by 3.5%. The sensitivity and specificity of the RIFLE criteria using estimated baseline creatinine were 76% and 95%. Renal replacement therapy was required for 17% of the AKI patients. One year survival of AKI patients was 51%, but only 2.5% of patients surviving 90 days required chronic renal replacement therapy.

CONCLUSIONS

The incidence of AKI in the ICU was lower than previously published, perhaps due to overestimation of AKI using estimated baseline creatinine or bias from tertiary referrals. AKI patients have high mortality, but the survivors have a low incidence of end-stage renal failure.

Predictive value of acute kidney injury in medical intensive care patients with sepsis originating from different infection sites

INTRODUCTION

Sepsis is the most common noncoronary cause of mortality in intensive care units (ICUs). This study compared different systems for predicting outcomes in a population of critically ill patients with sepsis originating from different infection sites, including intra-abdominal and pulmonary infections.

METHODS

This post hoc analysis of an accumulated database enrolled 161 heterogeneous critically ill patients diagnosed as severe sepsis and septic shock patients admitted to medical ICUs from June 2005 to May 2007. Demographic characteristics, clinical and laboratory variables, comorbidities and infection source were prospectively recorded on the first day of ICU admission. Patient evaluations included acute physiology and chronic health evaluation (APACHE) II, APACHE III, sequential organ failure assessment scores, organ system failure and risk of renal failure, injury to kidney, failure of kidney function, loss of kidney function and end-stage renal failure (RIFLE) classification.

RESULTS

Regarding the different originating sites of severe sepsis, intra-abdominal infections and pulmonary infections had the highest mortality rates (83.3% and 48.5%, respectively; P < 0.001). The APACHE III was the best mortality predictor for the overall sepsis population [areas under the receiver operating characteristic curve (AUROC) 0.800], whereas RIFLE classification was the best predictor in those with intra-abdominal infection (AUROC 0.856). The AUROC analyses verified that RIFLE classification had significantly (P < 0.05) better discriminatory power for predicting hospital mortality in patients with intra-abdominal infections than in those with pulmonary infections (AUROC 0.545).

CONCLUSIONS

This investigation confirms that different infection sites have different outcomes. In terms of mortality prediction, outcome scoring systems are significantly more accurate in patients with intra-abdominal infections than in those with pulmonary infections.

Impact of acute kidney injury on one-year survival after surgery for aortic dissection

BACKGROUND

Surgical treatment is an option for both type A aortic dissection and complicated type B aortic dissection. Acute kidney injury (AKI) influences the disease course after surgery. Our hypothesis was that AKI should be an important prognostic factor for aortic dissection after surgical treatment.

METHODS

Between July 2005 and October 2010, 268 patients (mean age 53 ± 14 years; range, 16 to 88) underwent open surgery for aortic dissection. We reviewed the clinical presentations, surgical variables, and postoperative outcomes to identify the risk factors of death. The 256 patients were divided into groups, with and without AKI, within 24 hours after operation according to the RIFLE (acronym for risk, injury, failure, loss, end stage) criteria.

RESULTS

The in-hospital mortality rate was 17.9%, the 1-year mortality rate was 18.7%, and the major adverse cardiac events rate within 1 year was 29.9%. In multivariate analysis, patients more than 70 years of age (hazard ratio [HR] 2.390, p = 0.029), cardiogenic shock (HR 2.895, p = 0.005), preoperative ventilator use (HR 4.137, p = 0.018), operation at midnight (HR 2.295, p = 0.028), longer bypass time (HR 1.007, p < 0.001), and AKI (HR 2.552, p = 0.041) were clinical predictors of mortality. Kaplan-Meier analysis showed that the survival rate was strongly correlated with the severity of AKI by the RIFLE criteria. The independent predictors of AKI included hypertension (odds ratio 2.340, p = 0.027), sepsis (odds ratio 2.594, p = 0.043), and lower limb malperfusion (odds ratio 4.558, p = 0.022).

CONCLUSIONS

Our study provides outcomes of postoperative aortic dissection. We found that AKI was a predictor of 1-year mortality by using the RIFLE criteria. Factors associated with increased 1-year mortality and AKI should be taken into consideration for surgery and postoperative care.

Acute kidney injury classification: AKIN and RIFLE criteria in critical patients

Acute kidney injury (AKI) is a common and serious complication in critically ill patients. The mortality rate remains high despite improved renal replacement techniques. A possible cause of the high mortality rate is that intensive care unit patients tend to be older and more debilitated than before. Pathophysiological factors associated with AKI are also implicated in the failure of other organs, indicating that AKI is often part of a multiple organ failure syndrome. Until recently, there was a lack of consensus as to the best definition, characterization, and evaluation of acute renal failure. This lack of a standard definition has been a major impediment to progress in clinical and basic research. The introduction of the risk, injury, failure, loss, and end-stage kidney disease criteria and the modified version proposed by the Acute Kidney Injury Network have increased the conceptual understanding of AKI syndrome, and these criteria have been successfully tested in clinical studies. This article reviews current findings concerning the application of these criteria for assessing epidemiology and predicting outcome in specific homogeneous critically ill patient groups.

Association of statin use with risk and outcome of acute kidney injury in community-acquired pneumonia

BACKGROUND AND OBJECTIVES

Sepsis is a leading cause of AKI. Animal studies suggest that the pleiotropic effect of statins attenuates the risk for AKI and decreases mortality. This study examined whether statin use was associated with a lower risk for pneumonia-induced AKI and 1-year and cause-specific mortality in patients with AKI.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Multicenter, prospective cohort study of 1836 patients hospitalized with community-acquired pneumonia.

RESULTS

Baseline characteristics differed among statin users and nonusers. Of the 413 patients (22.5%) who received a statin before hospitalization, statin treatment, when adjusted for differences in age, severity of pneumonia, admission from nursing home, health insurance, and propensity for statin use, did not reduce the risk for AKI (odds ratio [OR], 1.32 [95% confidence interval (CI), 1.02-1.69]; P=0.05). Of patients with AKI (n=631), statin use was associated with a lower risk for death at 1 year (27.8% versus 38.8%; P=0.01), which was not significant when adjusted for differences in age, severity of pneumonia and AKI, use of mechanical ventilation, and propensity score (OR, 0.72 [95% CI, 0.50-1.06]; P=0.09). Among patients with AKI, cardiovascular disease accounted for one third of all deaths.

CONCLUSIONS

In a large cohort of patients hospitalized with pneumonia, statins did not reduce the risk for AKI. Among patients with AKI, statin use was not associated with lower risk for death at 1 year. The higher risk for AKI observed among statin users may be due to indication bias.

Bactericidal antibiotics temporarily increase inflammation and worsen acute kidney injury in experimental sepsis

OBJECTIVE

To explore the relationships among bactericidal antimicrobial treatment of sepsis, inflammatory response, severity of acute kidney injury, and outcomes.

DESIGN

Controlled laboratory experiment.

SETTING

University laboratory.

INTERVENTIONS

Sepsis was induced by cecal ligation and puncture in 52 rats and was treated with either bactericidal antibiotics (ampicillin/sulbactam) or placebo (saline). Serial blood specimens were obtained after cecal ligation and puncture for serum creatinine, interleukin-6, and neutrophil gelatinase-associated lipocalin concentrations. RIFLE (Risk, Injury, Failure, Loss, End-stage kidney disease) criteria were used to assess severity of acute kidney injury. All animals were observed for survival up to 1 wk. In a separate experiment, six healthy animals were given antibiotics and renal function was assessed. Another 12 animals were euthanized 2 days after laparotomy for kidney histology.

MEASUREMENTS AND MAIN RESULTS

Survival in the placebo group was 50% compared with 81.8% in the antibiotic group (p < .05). Most animals (93%) without antibiotics developed acute kidney injury, of which 39% exhibited greater than a threefold rise in serum creatinine (RIFLE-F). Furthermore, survival decreased as acute kidney injury severity increased. Surprisingly, all antibiotic-treated animals developed acute kidney injury, of which 68.6% reached RIFLE-F. However, renal dysfunction was less persistent in these animals. Patterns of plasma interleukin-6 were similar to creatinine with higher concentrations seen earlier in antibiotic-treated animals but with faster resolution. Interleukin-6 concentration at 24 hrs was independently associated with the development of RIFLE-F. Histologic findings were consistent with functional parameters showing that antibiotics worsened acute kidney injury.

CONCLUSION

In polymicrobial sepsis, bactericidal antibiotics resulted in more inflammation and more severe acute kidney injury. However, resolution of inflammation and acute kidney injury was faster with antibiotics and correlated best with survival. These results suggest that transient worsening of renal function may be an expected consequence of sepsis therapy. These findings also question the value of peak severity of acute kidney injury as a primary end point and suggest that resolution of acute kidney injury may be more appropriate.

The RIFLE and AKIN classifications for acute kidney injury: a critical and comprehensive review

In May 2004, a new classification, the RIFLE (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease) classification, was proposed in order to define and stratify the severity of acute kidney injury (AKI). This system relies on changes in the serum creatinine (SCr) or glomerular filtration rates and/or urine output, and it has been largely demonstrated that the RIFLE criteria allows the identification of a significant proportion of AKI patients hospitalized in numerous settings, enables monitoring of AKI severity, and is a good predictor of patient outcome. Three years later (March 2007), the Acute Kidney Injury Network (AKIN) classification, a modified version of the RIFLE, was released in order to increase the sensitivity and specificity of AKI diagnosis. Until now, the benefit of these modifications for clinical practice has not been clearly demonstrated.

Here we provide a critical and comprehensive discussion of the two classifications for AKI, focusing on the main differences, advantages and limitations.

The effect of diabetes on mortality in critically ill patients: a systematic review and meta-analysis

Introduction

Critically ill patients with diabetes are at increased risk for the development of complications, but the impact of diabetes on mortality is unclear. We conducted a systematic review and meta-analysis to determine the effect of diabetes on mortality in critically ill patients, making a distinction between different ICU types.

Methods

We performed an electronic search of MEDLINE and Embase for studies published from May 2005 to May 2010 that reported the mortality of adult ICU patients. Two reviewers independently screened the resultant 3,220 publications for information regarding ICU, in-hospital or 30-day mortality of patients with or without diabetes. The number of deaths among patients with or without diabetes and/or mortality risk associated with diabetes was extracted. When only crude survival data were provided, odds ratios (ORs) and standard errors were calculated. Data were synthesized using inverse variance with ORs as the effect measure. A random effects model was used because of anticipated heterogeneity.

Results

We included 141 studies comprising 12,489,574 patients, including 2,705,624 deaths (21.7%). Of these patients, at least 2,327,178 (18.6%) had diabetes. Overall, no association between the presence of diabetes and mortality risk was found. Analysis by ICU type revealed a significant disadvantage for patients with diabetes for all mortality definitions when admitted to the surgical ICU (ICU mortality: OR [95% confidence interval] 1.48 [1.04 to 2.11]; in-hospital mortality: 1.59 [1.28 to 1.97]; 30-day mortality: 1.62 [1.13 to 2.34]). In medical and mixed ICUs, no effect of diabetes on all outcomes was found. Sensitivity analysis showed that the disadvantage in the diabetic surgical population was attributable to cardiac surgery patients (1.77 [1.45 to 2.16], P < 0.00001) and not to general surgery patients (1.21 [0.96 to 1.53], P = 0.11).

Conclusions

Our meta-analysis shows that diabetes is not associated with increased mortality risk in any ICU population except cardiac surgery patients.

Acute kidney injury in patients with severe traumatic brain injury: implementation of the acute kidney injury network stage system

BACKGROUND

There is limited information on the incidence and effect of acute kidney injury (AKI) in patients with severe traumatic brain injury (TBI), although AKI may affect outcome. Recently, acute kidney injury network (AKIN) classification has been widely accepted as a consensus definition for AKI. The aim of this study is to estimate the frequency and level of severity of AKI in patients with severe TBI by using AKIN criteria and to study whether AKI affects outcome.

METHODS

The authors retrospectively identified a total of 136 patients with severe TBI admitted to the neurosurgical center during a 3-year period ending May 2010. Demographic data, severity of TBI, serum creatinine, urine output, outcome at 6 month, and death were collected. Renal function was assessed by using AKIN criteria.

RESULTS

Thirty-one patients (23%) were classified as having AKI by using AKIN criteria during their hospitalization. Of them, 21 patients (68%) were stratified as stage 1, 7 patients (22%) as stage 2, and 3 patients (10%) as stage 3. Patients who developed AKI were older, had lower Glasgow coma scale at admission, and had higher level of admission serum creatinine and blood urea nitrogen. Patients with AKI had higher mortality and worse outcome when compared with patients with normal renal function. Furthermore, patients with mild renal dysfunction (stage 1 AKI) are also found having increased mortality and worse long-term outcome, compared with patients without renal dysfunction.

CONCLUSION

It is demonstrated using the newly defined AKIN criteria for renal dysfunction that AKI is a relatively common feature in patients with severe TBI, and even seemingly insignificant decrease in renal function may be associated with worse outcome. This study highlights the importance of close surveillance of renal function and stresses the value of renal hygiene in the severe TBI population.

Acute Kidney Injury in ADPKD Patients with Pneumonia

Background. In animal models, polycystic kidneys are susceptible to acute kidney injury (AKI). We examined the occurrence of AKI in a cohort of autosomal dominant polycystic kidney disease (ADPKD) and non-ADPKD patients with acute pneumonia. Design. All ADPKD patients admitted to Mayo Clinic Rochester for pneumonia from January 1990 to April 2010 were examined. Sixty-three patients had lobar infiltration and consolidation on chest X-ray. After excluding patients on dialysis, with organ transplantation, and on chronic immunosuppression, 24 remaining ADPKD patients were enrolled. Twenty-three of the 24 were matched with 92 (1 : 4 ratio) non-ADPKD pneumonia patients based on their baseline eGFR. AKI was defined as serum creatinine elevation ≥0.3 mg/dL. Results. Sixteen of the 23 ADPKD patients (69.6%) and 36 of the 92 (39.1%) non-ADPKD patients developed AKI, P = 0.008. In both groups, those who developed AKI had a lower baseline eGFR (41.1 ± 5.00 versus 58.7 ± 11.8 in ADPKD and 40.2 ± 3.65 versus 51.8 ± 2.24 mL/min/1.73 m(2) in the non-ADPKD group), more intensive care unit admissions, and longer hospital stays. AKI was associated with a reduced survival in both groups. Conclusions. Patients with ADPKD admitted for acute pneumonia had more frequent episodes of AKI than non-ADPKD patients with comparable kidney function.

Understanding urine output in critically ill patients

Urine output often is used as a marker of acute kidney injury but also to guide fluid resuscitation in critically ill patients. Although decrease of urine output may be associated to a decrease of glomerular filtration rate due to decrease of renal blood flow or renal perfusion pressure, neurohormonal factors and functional changes may influence diuresis and natriuresis in critically ill patients. The purpose of this review is to discuss the mechanisms of diuresis regulation, which may help to interpret the urine output in critically ill patients and the appropriate treatment to be initiated in case of changes in urine output.

Multiple-center evaluation of mortality associated with acute kidney injury in critically ill patients: a competing risks analysis

Introduction

In this study, we aimed to assess the association between acute kidney injury (AKI) and mortality in critically ill patients using an original competing risks approach.

Methods

Unselected patients admitted between 1997 and 2009 to 13 French medical or surgical intensive care units were included in this observational cohort study. AKI was defined according to the RIFLE criteria. The following data were recorded: baseline characteristics, daily serum creatinine level, daily Sequential Organ Failure Assessment (SOFA) score, vital status at hospital discharge and length of hospital stay. Patients were classified according to the maximum RIFLE class reached during their ICU stay. The association of AKI with hospital mortality with "discharge alive" considered as a competing event was assessed according to the Fine and Gray model.

Results

Of the 8,639 study patients, 32.9% had AKI, of whom 19.1% received renal replacement therapy. Patients with AKI had higher crude mortality rates and longer lengths of hospital stay than patients without AKI. In the Fine and Gray model, independent risk factors for hospital mortality were the RIFLE classes Risk (sub-hazard ratio (SHR) 1.58 and 95% confidence interval (95% CI) 1.32 to 1.88; P < 0.0001), Injury (SHR 3.99 and 95% CI 3.43 to 4.65; P < 0.0001) and Failure (SHR 4.12 and 95% CI 3.55 to 4.79; P < 0.0001); nonrenal SOFA score (SHR 1.19 per point and 95% CI 1.18 to 1.21; P < 0.0001); McCabe class 3 (SHR 2.71 and 95% CI 2.34 to 3.15; P < 0.0001); and respiratory failure (SHR 3.08 and 95% CI 1.36 to 7.01; P < 0.01).

Conclusions

By using a competing risks approach, we confirm in this study that AKI affecting critically ill patients is associated with increased in-hospital mortality.

Discrepancies in the RIFLE classification are due to the method used to assess the level of derangement of kidney function

PURPOSE

We hypothesized that RIFLE based on creatinine clearance (CrCl) is superior to that based on serum creatinine (sCr) or Cockroft-Gault (C-G) because it is an earlier marker of kidney dysfunction.

MATERIALS AND METHODS

At day 3 of admission, we compared the RIFLE based on sCr, C-G, and CrCl with 28-day mortality and development of RIFLE-F during intensive care unit stay.

RESULTS

Percentages in the RIFLE levels were similar for the 3 estimates, but the patients included in each level were different; with CrCl as the reference, κ statistic was 0.29 (95% confidence interval, 0.15-0.43) for sCr and 0.21 (0.07-0.36) for C-G. Mortality at day 28 was 19.3%, with percentages of mortality increasing with RIFLE based in CrCl but not sCr or C-G (area under the curve, 0.57 [45-72] for C-G; 0.57 [44-72] for sCr; and 0.64 [52-79] for CrCl). Logistic regression only showed an independent relationship with mortality for RIFLE measured with CrCl.

CONCLUSIONS

RIFLE classification using sCr or C-G at the third day of admission predicts outcome less accurately than with the use of CrCl. Because of the delay in the rise of sCr after a sudden glomerular filtration rate decrease, RIFLE based in CrCl may represent an advantage in terms of precocity.

Prognosis of patients on extracorporeal membrane oxygenation: the impact of acute kidney injury on mortality

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) has been utilized for patients in critical condition, such as those with life-threatening respiratory failure or postcardiotomy cardiogenic shock. This study analyzed the outcomes of patients treated with ECMO and identified the relationship between prognosis and the Acute Kidney Injury Network (AKIN) scores obtained at pre-ECMO support (AKIN0-hour); and at post-ECMO support 24 hours (AKIN24-hour) and 48 hours (AKIN48-hour).

METHODS

This study reviewed the medical records of 102 critically ill patients on ECMO support at a specialized intensive care unit at a tertiary care university hospital between March 2002 and January 2008. Demographic, clinical, and laboratory variables were retrospectively collected as survival predicators.

RESULTS

The overall mortality rate was 57.8%. The most common condition requiring ECMO support was cardiogenic shock. Goodness-of-fit was good for AKIN0-hour, AKIN24-hour, and AKIN48-hour criteria. The AKIN0-hour, AKIN24-hour, and AKIN48-hour scoring systems also had excellent areas under the receiver operating characteristic curve (0.804±0.046, 0.811±0.045, and 0.858±0.040, respectively). Furthermore, multiple logistic regression analysis indicated that AKIN48-hour, age, and Glasgow Coma Scale score on the first day of intensive care unit admission were independent risk factors for hospital mortality. Finally, cumulative survival rates at 6-month follow-up after hospital discharge differed significantly (p<0.05) for AKIN48-hour stage 0 versus AKIN48-hour stages 1, 2, and 3; and AKIN48-hour stage 1 and 2 versus AKIN48-hour stage 3.

CONCLUSIONS

During ECMO support, the AKIN48-hour scoring system proved to be a reproducible evaluation tool with excellent prognostic abilities for these patients.

Acute kidney injury: current perspectives

Acute kidney injury (AKI) increases morbidity and mortality, particularly for the critically ill. Recent definitions standardizing AKI to reflect graded changes in serum creatinine and urine output (per the Risk, Injury, Failure, Loss, and End-stage renal failure [RIFLE] and Acute Kidney Injury Network [AKIN] criteria) with severity of renal injury and developments in AKI pathobiology are being utilized to identify biomarkers of early kidney injury. These developments may be useful in the early intervention of preventing AKI. Although there has been progress in the management of AKI, therapeutic challenges include appropriate prophylaxis prior to contrast administration, use of diuretics, vasopressors, and the type and dose of renal replacement therapy. Future use of bioartificial dialyzers, plasma therapies, and the possibility of stem cell regeneration of injured kidney tissue are being actively investigated to provide alternative treatment options for AKI. This review aims to provide an overview of current practices, available therapies, and continued research in AKI therapy.

Outcome scoring systems for acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is commonly diagnosed in intensive care units (ICUs), often in association with acute kidney injury. In this study, we compared the predictive value of outcome scoring systems: Acute Physiology and Chronic Health Evaluation IV (APACHE IV), earlier APACHE models, Sequential Organ Failure Assessment (SOFA), the Risk of renal failure, Injury to the kidney, Failure of kidney function, Loss of kidney function, and End-stage renal failure (RIFLE) classification, and Acute Lung Injury score in critically ill patients with ARDS. We retrospectively abstracted data from the medical records of 135 critically ill ARDS patients in two medical ICUs of a tertiary care hospital from December 1999 to June 2006. Overall mortality rate was 65% (88/135). Forward conditional logistic regression identified APACHE IV, alveolar-arterial O2 tension difference, age, sepsis, and maximum RIFLE (RIFLEmax) score on ICU days 1 and 3 to be independent predictors of hospital mortality. The area under the receiver operating characteristic curve for the APACHE IV score revealed good fit (Hosmer and Lemeshow goodness-of-fit test results) and discriminative power (area under the receiver operating characteristic curve, 0.792 ± 0.038; P < 0.001). The cumulative survival rates at 6-month follow-up after hospital discharge were significantly (P < 0.001) different among ARDS patients with APACHE IV mortality rate 35% or less and APACHE IV mortality rate higher than 35%. The APACHE IV score and RIFLEmax score are predictors of hospital mortality in ARDS patients, with APACHE IV demonstrating desirable properties of prognostic accuracy.

Extravascular lung water correlates multiorgan dysfunction syndrome and mortality in sepsis

Background

This study was designated to investigate whether increased extravascular lung water index (EVLWI) may correlate multiple organ dysfunction syndrome (MODS) and mortality in sepsis.

Methods

We designed a prospective cohort study in an intensive care unit of a tertiary care hospital. Sixty-seven patients with severe sepsis were included. Data were used to determine an association between EVLWI and the development of MODS and mortality. These connections were determined by the multiple logistic regression, plotting the receiver operating characteristic (ROC) curve and by Spearman test.

Results

EVLWI levels were higher in MODS patients on day 1 (median (IQR), 18(12.8–23.9) ml/kg, n = 38, p<0.0001) than in those without (median (IQR), 12.4 (7.9–16.3) ml/kg, n = 29) and day 3 (median (IQR), 17.8 (11.2–22.8) ml/kg, n = 29, p = 0.004) than in those without (median (IQR), 12.4 (8.0–16.3) ml/kg, n = 29). EVLWI was used as an independent predictor of the development of MODS (odds ratio, 1.6; p = 0.005; 95% confidence interval, 1.2∼2.2) during ICU stay. The area under the ROC curve showed that EVLWI levels could predict MODS (0.866) and mortality (0.881) during ICU stay. Meanwhile, the higher of SOFA score, the more EVLWI was found on day 1 (r = 0.7041, p<0.0001) and day 3 (r = 0.7732, p<0.0001).

Conclusions

Increased EVLWI levels correlates development of MODS and mortality during the patients' ICU stay. Further more, the potential of novel treatment in severe sepsis with lung injury may develop.

Kupffer cell depletion reduces hepatic inflammation and apoptosis but decreases survival in abdominal sepsis

OBJECTIVE

During abdominal sepsis, the activation of hepatic Kupffer cells (KC) and its consequences are of central interest. This study evaluates the impact of selective KC depletion on hepatic microcirculation, cytokine release, and systemic alterations in the colon ascendens stent peritonitis (CASP), a model of polymicrobial abdominal sepsis.

METHODS

For KC depletion clodronate liposomes were injected 24 h before CASP surgery in female C57BL/6N mice. Three and 12 h after CASP, in-vivo fluorescence microscopy of the liver was performed. Analysis of hepatocellular apoptosis was conducted by immunohistochemistry. In addition, levels of tumor necrosis factor (TNF), IL-6, and IL-10 in the liver, lungs, spleen, and plasma were determined, and bacteriology and survival analysis were performed.

RESULTS

CASP led to significant sinusoidal perfusion failure, increased leukocyte recruitment, hepatocellular apoptosis and increased levels of TNF, IL-6, and IL-10 in the liver and plasma. KC depletion before CASP significantly reduced leukocyte recruitment to the liver and hepatocellular apoptosis. IL-10 secretion decreased dramatically in the liver and plasma of KC-depleted septic mice. In contrast, TNF levels were clearly elevated after clodronate treatment. In the lung and spleen, a compensatory upregulation of IL-10 could be detected after KC depletion. Clodronate treatment resulted in a significant reduction in survival.

CONCLUSION

The results indicate that KC depletion is locally protective in polymicrobial abdominal sepsis, as it reduces hepatic inflammation and apoptosis. These effects could be observed in the presence of clearly elevated TNF levels. However, the lack of IL-10 in KC-depleted mice resulted in a detrimental systemic proinflammation.

Long-term risk of mortality after acute kidney injury in patients with sepsis: a contemporary analysis

Background

Acute kidney injury (AKI) is associated with increased short-term mortality of septic patients; however, the exact influence of AKI on long-term mortality in such patients has not yet been determined.

Methods

We retrospectively evaluated the impact of AKI, defined by the "Risk, Injury, Failure, Loss of kidney function, End-stage kidney disease" (RIFLE) classification based on creatinine criteria, on 2-year mortality in a cohort of 234 hospital surviving septic patients who had been hospitalized at the Infectious Disease Intensive Care Unit of our Hospital.

Results

Mean-follow-up was 21 ± 6.4 months. During this period, 32 patients (13.7%) died. At 6 months, 1 and 2 years of follow-up, the cumulative probability of death of patients with previous AKI was 8.3, 16.9 and 34.2%, respectively, as compared with 2.2, 6 and 8.9% in patients without previous AKI (log-rank, P < 0.0001). In the univariate analysis, age (hazard ratio 1.4, 95% CI 1.2-1.7, P < 0.0001), as well as pre-existing cardiovascular disease (hazard ratio 3.6, 95% CI 1.4-9.4, P = 0.009), illness severity as evaluated by nonrenal APACHE II (hazard ratio 1.3, 95% CI 1.1-1.6, P = 0.002), and previous AKI (hazard ratio 4.2, 95% CI 2.1-8.5, P < 0.0001) were associated with increased 2-year mortality, while gender, race, pre-existing hypertension, cirrhosis, HIV infection, neoplasm, and baseline glomerular filtration rate did not. In the multivariate analysis, however, only previous AKI (hazard ratio 3.2, 95% CI 1.6-6.5, P = 0.001) and age (hazard ratio 1.4, 95% CI 1.2-1.6, P < 0.0001) emerged as independent predictors of 2-year mortality.

Conclusions

Acute kidney injury had a negative impact on long-term mortality of patients with sepsis.

Incidence and prognostic implications of acute kidney injury on admission in patients with community-acquired pneumonia

BACKGROUND

A consensus definition of acute kidney injury (AKI)-the risk, injury, failure, loss, and end-stage kidney disease (RIFLE) classification-predicts mortality in general hospital and ICU populations. We aimed to assess its value on admission in patients with community-acquired pneumonia (CAP).

METHODS

A prospective observational study with CAP was carried out. We classified each patient according to his or her maximum RIFLE class using admission creatinine (risk, ≥ 1.5 × baseline creatinine; injury, ≥ 2 × baseline; failure, ≥ 3 × baseline; no-AKI, < 1.5 × baseline). Outcomes were 30-day mortality, requirement for mechanical ventilation and inotropic support (MV/IS), and requirement for renal replacement therapy (RRT).

RESULTS

A total of 1,241 patients were included (no-AKI, 1,018; risk, 130; injury, 63; failure, 30). On multivariate analysis, factors predicting development of AKI include severity of pneumonia (adjusted odds ratio [AOR], 1.74; 95% CI, 1.46-2.08; P < .0001), elevated C-reactive protein (AOR, 1.04; 95% CI, 1.03-1.06; P < .0001), and prior use of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin-II-receptor blockers (AIIBs) (AOR, 1.77; 95% CI, 1.19-2.58; P = .005). Adjusting for severity of pneumonia, RIFLE criteria independently predicted 30-day mortality (AOR, 1.48; 95% CI, 1.15-1.91; P = .002), requirement for MV/IS (AOR, 2.22; 95% CI, 1.74-2.83; P < .0001), and RRT (AOR, 3.20; 95% CI, 2.01-5.11; P < .0001). Prior use of ACEIs or AIIBs was not associated with adverse outcome in either the entire cohort or patients without AKI.

CONCLUSION

The RIFLE classification is a simple tool to assess and classify AKI on admission and independently predicts 30-day mortality and the need for MV/IS and RRT in patients with CAP.

Serum sodium predicts prognosis in critically ill cirrhotic patients

BACKGROUND

End-stage liver disease is often complicated by hyponatremia. Cirrhotic patients with hyponatremia admitted to intensive care units (ICUs) have high mortality rates. This study analyzed the outcomes of critically ill cirrhotic patients and identified the prognostic value of serum sodium concentration.

METHODS

One hundred twenty-six consecutive cirrhotic patients admitted to the ICU of a tertiary center during a 1.5-year period were enrolled in this study. Demographic, clinical, and laboratory variables on the first day of ICU admission were prospectively recorded for post hoc analysis.

RESULTS

Overall hospital mortality was 65.1%. Comparing with serum sodium >135 mmol/L, patients with serum sodium <or=135 mmol/L had a greater frequency of ascites, illness severity scores, hepatic encephalopathy, sepsis, renal failure, and in-hospital mortality (55.9% vs. 73.1%, P=0.043). Multiple Cox proportional hazards analysis revealed that serum sodium levels, hepatocellular carcinoma, and sequential organ failure assessment scores on the first day of ICU admission were independent risk factors for 6-month mortality. Cumulative survival rates at 6-month follow-up after hospital discharge differed significantly (P<0.05) between patients with serum sodium >135 mmol/L versus those with serum sodium <or=135 mmol/L.

CONCLUSIONS

Low serum sodium levels in critically ill cirrhotic patients are associated with high complications of liver cirrhosis, in-hospital mortality, and poor short-term prognosis. The serum sodium concentration is important predictor of survival among candidates for liver transplantation. Future research with sequential application of serum sodium may reflect the dynamic aspects of clinical conditions, thus providing complete data for mortality risk.

Procalcitonin in sepsis and systemic inflammation: a harmful biomarker and a therapeutic target

The worldwide yearly mortality from sepsis is substantial, greater than that of cancer of the lung and breast combined. Moreover, its incidence is increasing, and its response to therapy has not appreciably improved. In this condition, the secretion of procalcitonin (ProCT), the prohormone of calcitonin, is augmented greatly, attaining levels up to thousands of fold of normal. This hypersecretion emanates from multiple tissues throughout the body that are not traditionally viewed as being endocrine. The serum values of ProCT correlate with the severity of sepsis; they recede with its improvement and worsen with exacerbation. Accordingly, as highlighted in this review, serum ProCT has become useful as a biomarker to assist in the diagnosis of sepsis, as well as related infectious or inflammatory conditions. It is also a useful monitor of the clinical course and prognosis, and sensitive and specific assays have been developed for its measurement. Moreover, it has been demonstrated that the administration of ProCT to septic animals greatly increases mortality, and several toxic effects of ProCT have been elucidated by in vitro experimental studies. Antibodies have been developed that neutralize the harmful effects of ProCT, and their use markedly decreases the symptomatology and mortality of animals that harbour a highly virulent sepsis analogous to that occurring in humans. This therapy is facilitated by the long duration of serum ProCT elevation, which allows for a broad window of therapeutic opportunity. An experimental groundwork has been established that suggests a potential applicability of such therapy in septic humans.

Acute kidney injury in non-severe pneumonia is associated with an increased immune response and lower survival

While sepsis is a leading cause of acute kidney injury in critically ill patients, the relationship between immune response and acute kidney injury in less severely ill patients with infection is not known. Here we studied the epidemiology, 1-year mortality, and immune response associated with acute kidney injury in 1836 hospitalized patients with community-acquired severe and non-severe pneumonia. Acute kidney injury developed in 631 patients of whom 329 had severe and 302 had non-severe sepsis. Depending on the subgroup classification, 16-25% of the patients with non-severe pneumonia also developed acute kidney injury. In general, patients with acute kidney injury were older, had more comorbidity, and had higher biomarker concentrations (interleukin-6, tumor necrosis factor, D-dimer) even among patients without severe sepsis. The risk of death associated with acute kidney injury varied when assessed by Gray's survival model and after adjusting for differences in age, gender, ethnicity, and comorbidity. This risk was significantly higher immediately after hospitalization but gradually fell over time in the overall cohort and in those with non-severe pneumonia. A significantly higher risk of death (hazard ratio 1.29) was also present in those never admitted to an intensive care unit. Hence acute kidney injury is common even among patients with non-severe pneumonia and is associated with higher immune response and an increased risk of death.

Redefining renal dysfunction in trauma: implementation of the Acute Kidney Injury Network staging system

BACKGROUND

Acute renal failure (ARF) in trauma patients is associated with high mortality rates. There is currently no consensus definition for renal failure, however, the American College of Surgeons' Committee on Trauma (ACSCOT) defines ARF as a serum creatinine > or =3.5, blood urea nitrogen > 100, or renal replacement therapy. We hypothesize that by using the Acute Kidney Injury Network (AKIN) staging system we would identify smaller changes in renal function that may impact outcome, and may serve as a marker for mortality and other organ dysfunction.

METHODS

We retrospectively identified all trauma patients admitted to the surgical intensive care unit (SICU) for >48 hours during a 3-year period ending December 2007. Hourly urine output, serum creatinine, demographic data, trauma scores, admission vital signs, ICU and hospital length of stay, need for renal replacement therapy, organ failure, and death were collected and were stratified according to AKIN and ACSCOT renal dysfunction criteria. Trauma patients admitted to the SICU who did not develop renal dysfunction were used as controls.

RESULTS

A total of 571 patients were studied. Of those, only 17 patients (3.0%) were classified as having ARF by the ACSCOT criteria, whereas 170 (29.8%) had kidney injury using the AKIN criteria (146, stage 1; 15, stage 2; 9, stage 3). Compared with patients admitted to the ICU for > or =48 hours with normal renal function, patients meeting AKIN criteria had longer hospital and ICU length of stay (p < 0.001). Patients meeting AKIN criteria also had an increased incidence of multiple organ failure and death (p < 0.03).

CONCLUSIONS

Stratification using the AKIN criteria for acute kidney injury identifies an increased number of patients with renal dysfunction compared with the current ACSCOT criteria. Importantly, these patients have an increased risk of multiple organ failure and death. Inclusion into the AKIN criteria may be a marker for later morbidity and mortality.

Clinical review: RIFLE and AKIN--time for reappraisal

In recent years, the use of the consensus definitions of acute kidney injury (RIFLE and AKIN) in the literature has increased substantially. This indicates a highly encouraging acceptance by the medical community of a unifying definition for acute kidney injury. This is a very important and positive step in the right direction. There remains some variation in how the criteria are interpreted and used in the literature, including use/nonuse of urine output criteria, use of change in estimated glomerular filtration rate rather than change in creatinine, and choice of baseline creatinine. The present review is intended to aid the reader in critically appraising studies using these consensus definitions. Since no single definition will be perfect, a logical next step would be to reconcile existing definitions, moving the medical community towards using a single consensus definition as has been done with sepsis and acute lung injury/acute respiratory distress syndrome. As new data emerge, integration of novel biomarkers into the consensus definition will be a welcome refinement.