Incidence, risk factors and 90-day mortality of patients with acute kidney injury in Finnish intensive care units: the FINNAKI study

Associations between tricuspid annular plane systolic excursion to reflect right ventricular function and acute kidney injury in critically ill patients: a SICS-I sub-study

BACKGROUND

Acute kidney injury (AKI) occurs in up to 50% of all critically ill patients and hemodynamic abnormalities are assumed to contribute, but their nature and share is still unclear. We explored the associations between hemodynamic variables, including cardiac index and right ventricular function, and the occurrence of AKI in critically ill patients.

METHODS

In this prospective cohort study, we included all patients acutely admitted to an intensive care unit (ICU). Within 24 h after ICU admission clinical and hemodynamic variables were registered including ultrasonographic measurements of cardiac index and right ventricular function, assessed using tricuspid annular plane systolic excursion (TAPSE) and right ventricular systolic excursion (RV S'). Maximum AKI stage was assessed according to the KDIGO criteria during the first 72 h after admission. Multivariable logistic regression modeling was used including both known predictors and univariable significant predictors of AKI. Secondary outcomes were days alive outside ICU and 90-day mortality.

RESULTS

A total of 622 patients were included, of which 338 patients (54%) had at least AKI stage 1 within 72 h after ICU admission. In the final multivariate model higher age (OR 1.01, 95% CI 1.00-1.03, for each year), higher weight (OR 1.03 CI 1.02-1.04, for each kg), higher APACHE IV score (OR 1.02, CI 1.01-1.03, per point), lower mean arterial pressure (OR 1.02, CI 1.01-1.03, for each mmHg decrease) and lower TAPSE (OR 1.05, CI 1.02-1.09 per millimeter decrease) were all independent predictors for AKI in the final multivariate logistic regression model. Sepsis, cardiac index, RV S' and use of vasopressors were not significantly associated with AKI in our data. AKI patients had fewer days alive outside of ICU, and their mortality rate was significantly higher than those without AKI.

CONCLUSIONS

In our cohort of acutely admitted ICU patients, the incidence of AKI was 54%. Hemodynamic variables were significantly different between patients with and without AKI. A worse right ventricle function was associated with AKI in the final model, whereas cardiac index was not.

Common Inflammation-Related Candidate Gene Variants and Acute Kidney Injury in 2647 Critically Ill Finnish Patients

Acute kidney injury (AKI) is a syndrome with high incidence among the critically ill. Because the clinical variables and currently used biomarkers have failed to predict the individual susceptibility to AKI, candidate gene variants for the trait have been studied. Studies about genetic predisposition to AKI have been mainly underpowered and of moderate quality. We report the association study of 27 genetic variants in a cohort of Finnish critically ill patients, focusing on the replication of associations detected with variants in genes related to inflammation, cell survival, or circulation. In this prospective, observational Finnish Acute Kidney Injury (FINNAKI) study, 2647 patients without chronic kidney disease were genotyped. We defined AKI according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria. We compared severe AKI (Stages 2 and 3, n = 625) to controls (Stage 0, n = 1582). For genotyping we used iPLEX^TM Assay (Agena Bioscience). We performed the association analyses with PLINK software, using an additive genetic model in logistic regression. Despite the numerous, although contradictory, studies about association between polymorphisms rs1800629 in TNFA and rs1800896 in IL10 and AKI, we found no association (odds ratios 1.06 (95% CI 0.89–1.28, p = 0.51) and 0.92 (95% CI 0.80–1.05, p = 0.20), respectively). Adjusting for confounders did not change the results. To conclude, we could not confirm the associations reported in previous studies in a cohort of critically ill patients.

Modification of sequential organ failure assessment score using acute kidney injury classification

PURPOSE

To assess the predictive validity of a modified Sequential Organ Failure Assessment (SOFA) score, of which the renal component was replaced with Kidney Disease Improving Global Outcomes (KDIGO) classification of Acute Kidney Injury (AKI).

MATERIALS AND METHODS

Using a prospective cohort study on AKI in Japan, we replaced the renal component of SOFA score with AKI stages according to the KDIGO criteria except that initiation of renal replacement therapy was assigned four points. We assessed the predictive validity of KDIGO-based SOFA score for hospital and ICU mortality by comparing the areas under the receiver operating characteristic curve (AUC) derived from logistic regression models with that of the original SOFA score.

RESULTS

2292 patients were registered. Overall hospital mortality was 11.6%, and ICU mortality was 5.1%. KDIGO-based SOFA score was moderately correlated with APACHE II score (rho = 0.476). The AUC for hospital and ICU mortality of KDIGO-based and the original SOFA score were 0.749 vs 0.745 (p = .393) and 0.790 vs 0.791 (p = .900).

CONCLUSIONS

The prognostic performance of KDIGO-based SOFA score was not superior but comparable to that of the original SOFA score.

ICU survival and need of renal replacement therapy with respect to AKI duration in critically ill patients

BACKGROUND

Transient and persistent acute kidney injury (AKI) could share similar physiopathological mechanisms. The objective of our study was to assess prognostic impact of AKI duration on ICU mortality.

DESIGN

Retrospective analysis of a prospective database via cause-specific model, with 28-day ICU mortality as primary end point, considering discharge alive as a competing event and taking into account time-dependent nature of renal recovery. Renal recovery was defined as a decrease of at least one KDIGO class compared to the previous day.

SETTING

23 French ICUs.

PATIENTS

Patients of a French multicentric observational cohort were included if they suffered from AKI at ICU admission between 1996 and 2015.

INTERVENTION

None.

RESULTS

A total of 5242 patients were included. Initial severity according to KDIGO creatinine definition was AKI stage 1 for 2458 patients (46.89%), AKI stage 2 for 1181 (22.53%) and AKI stage 3 for 1603 (30.58%). Crude 28-day ICU mortality according to AKI severity was 22.74% (n = 559), 27.69% (n = 327) and 26.26% (n = 421), respectively. Renal recovery was experienced by 3085 patients (58.85%), and its rate was significantly different between AKI severity stages (P < 0.01). Twenty-eight-day ICU mortality was independently lower in patients experiencing renal recovery [CSHR 0.54 (95% CI 0.46-0.63), P < 0.01]. Lastly, RRT requirement was strongly associated with persistent AKI whichever threshold was chosen between day 2 and 7 to delineate transient from persistent AKI.

CONCLUSIONS

Short-term renal recovery, according to several definitions, was independently associated with higher mortality and RRT requirement. Moreover, distinction between transient and persistent AKI is consequently a clinically relevant surrogate outcome variable for diagnostic testing in critically ill patients.

VolumE maNagement Under body composition monitoring in critically ill patientS on CRRT: study protocol for a randomized controlled trial (VENUS trial)

Background

Despite recent technical advances in the management of acute kidney injury (AKI), such as continuous renal replacement therapy (CRRT), intensive care unit mortality is still high, at approximately 40 to 50%. Although several factors have been reported to predict mortality in AKI patients, fluid overload (FO) during CRRT is a well-known predictor of patient survival. However, FO has been mostly quantified as an arithmetical calculation and determined on the basis of the physicians’ perception. Even though such quantification and assessment provides an easy evaluation of a patient’s fluid status and is a simple method, it is not applicable unless a detailed record of fluid monitoring is available. Furthermore, the method cannot differentiate excess water in individual water compartments but can only reflect excess total body water. Bioimpedance analysis (BIA) has been used to measure the nutritional component of body composition and is a promising tool for the measurement of volume status. However, there has been no prospective interventional study for fluid balance among CRRT-treated AKI patients using BIA. Therefore, we will investigate the usefulness of fluid management using the InBody S10 (InBody®, Seoul, Korea), a BIA tool, compared with that of generally used quantification methods.

Methods/design

This will be a multicenter, prospective, randomized controlled trial. A total of 244 patients undergoing CRRT treatment will be enrolled and randomly assigned to receive either to InBody S10-guided management or to fluid management based only on clinical information for 7 days. The primary outcome is to compare the rate of euvolemic status 7 days after the initiation of CRRT, with a secondary outcome being to compare the 28-, 60-, and 90-day mortality rates between the two groups.

Discussion

This will be the first clinical trial to investigate the effect of using BIA-guided fluid management to achieve euvolemia in CRRT-treated AKI patients.

Trial registration

ClinicalTrials.gov, ID: NCT03330626. Registered on 6 November 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3056-y) contains supplementary material, which is available to authorized users.

Human atrial natriuretic peptide for acute kidney injury in adult critically ill patients: A multicenter prospective observational study

PURPOSE

Acute kidney injury (AKI) is common in the intensive care unit (ICU). Selected clinical studies have implied human atrial natriuretic peptide (hANP) improves renal function; however, the treatment effects for AKI are unclear.

METHODS

A multicenter prospective observational study in 13 Japanese ICUs. The effects of hANP were estimated by the standardized mortality ratio weighted analyses of generalized linear models using propensity scores. The primary outcome was renal replacement therapy (RRT) or death in the ICU.

RESULTS

Of 904 patients with AKI, 63 received hANP as a treatment for AKI. The primary outcome occurred in 20.5% (185/904). HANP did not reduce the risk of RRT or death in the ICU (risk ratio 1.12, 95% confidence interval [CI] 0.74 to 1.69) and was associated with a lower mean arterial pressure (β -3.8 mmHg, 95%CI -7.6 to -0.1), a longer hospital length of stay (β 12.0 days, 95%CI 1.2 to 22.8) and a lower eGFR at hospital discharge (β -10.4 mL/min/m², 95%CI -19.1 to -1.7). No beneficial effect was observed in subgroups of cardiovascular surgery, sepsis, nor chronic kidney disease.

CONCLUSIONS

In critically ill patients with AKI, the treatment effect of hANP was not evident on dialysis-free survival in the ICU.

One- and three-year outcomes in patients treated with intermittent hemodialysis for acute kidney injury: prospective observational multicenter post-hoc FINNAKI study

BACKGROUND

Studies reporting renal and overall survival after acute kidney injury (AKI) treated exclusively with intermittent modalities of renal replacement therapy (IRRT) are rare. This study focused on outcomes of AKI patients treated with IRRT both in intensive care units (ICUs) and non-ICU dialysis units.

METHODS

This prospective observational study was carried on during a 5-month period in 17 ICUs and 17 non-ICUs. ICU and non-ICU patients (total n = 138; 65 ICU, 73 non-ICU) requiring RRT for AKI and chosen to receive IRRT were included. Patient and RRT characteristics as well as outcomes at 90 days, 1 year, and 3 years were registered.

RESULTS

Characteristics of ICU and non-ICU patients differed markedly. Pre-existing chronic kidney disease (CKD) and chronic heart failure were significantly more common among non-ICU patients. At 1 year, RRT dependence was significantly more common in the non-ICU group. At 3 years, there was no significant difference between the groups either in RRT dependence or mortality.

CONCLUSION

Outcome of AKI patients treated with IRRT is dismal with regard to 3-year kidney function and mortality. Although pre-existing CKD emerged as a major risk factor for end-stage renal disease after AKI, the poor kidney survival was also seen in patients without prior CKD.

Hemodynamic support in the early phase of septic shock: a review of challenges and unanswered questions

Background

Improving sepsis support is one of the three pillars of a 2017 resolution according to the World Health Organization (WHO). Septic shock is indeed a burden issue in the intensive care units. Hemodynamic stabilization is a cornerstone element in the bundle of supportive treatments recommended in the Surviving Sepsis Campaign (SSC) consecutive biannual reports.

Main body

The “Pandera’s box” of septic shock hemodynamics is an eternal debate, however, with permanent contentious issues. Fluid resuscitation is a prerequisite intervention for sepsis rescue, but selection, modalities, dosage as well as duration are subject to discussion while too much fluid is associated with worsen outcome, vasopressors often need to be early introduced in addition, and catecholamines have long been recommended first in the management of septic shock. However, not all patients respond positively and controversy surrounding the efficacy-to-safety profile of catecholamines has come out. Preservation of the macrocirculation through a “best” mean arterial pressure target is the actual priority but is still contentious. Microcirculation recruitment is a novel goal to be achieved but is claiming more knowledge and monitoring standardization. Protection of the cardio-renal axis, which is prevalently injured during septic shock, is also an unavoidable objective. Several promising alternative or additive drug supporting avenues are emerging, trending toward catecholamine’s sparing or even “decatecholaminization.” Topics to be specifically addressed in this review are: (1) mean arterial pressure targeting, (2) fluid resuscitation, and (3) hemodynamic drug support.

Conclusion

Improving assessment and means for rescuing hemodynamics in early septic shock is still a work in progress. Indeed, the bigger the unresolved questions, the lower the quality of evidence.

Short- and long-term outcomes after postsurgical acute kidney injury requiring dialysis

Objective

Prompt assessment of perioperative complications is critical for the comprehensive care of surgical patients. Acute kidney injury requiring dialysis (AKI-D) is associated with high mortality, yet little is known about how long-term outcomes of patients have evolved. The association of AKI-D with postsurgical outcomes has not been well studied.

Methods

We investigated patients from the National Health Insurance Research Database and validated by the multicenter Clinical Trial Consortium for Renal Diseases cohort. All patients with AKI-D 18 years or older undergoing four major surgeries (cardiothoracic, esophagus, intestine, and liver) were retrospectively investigated (N=106,573). Patient demographics, surgery type, comorbidities before admission, and postsurgical outcomes, including the in-hospital, 30-day, and long-term mortality together with dialysis dependence were collected.

Results

AKI-D is the top risk factor for 30-day and long-term mortality after major surgery. Of 1,664 individuals with AKI-D and 6,656 matched controls, AKI-D during the hospital stay was associated with in-hospital (adjusted hazard ratio [aHR]=3.04, 95% CI 2.79–3.31), 30-day (aHR=3.65, 95% CI 3.37–3.94), and long-term (aHR=3.22, 95% CI 3.01–3.44) mortality. Patients undergoing cardiothoracic surgery (CTS) showed less in-hospital (aHR=0.85, 95% CI 0.75–0.97), 30-day (aHR=0.79, 95% CI 0.70–0.89), and long-term (aHR=0.80, 95% CI 0.72–0.90) mortality compared with non-CTS patients with AKI-D. CTS patients had a high risk of 30-day dialysis dependence (subhazard ratio [sHR]=1.67, 95% CI 1.18–2.38), but the risk of long-term dialysis dependence was similar (sHR=1.38, 95% CI 0.96–2.00) after AKI-D by taking mortality as a competing risk. Non-CTS patients had more comorbidities of sepsis, azotemia, hypoalbuminemia, and metabolic acidosis compared with CTS patients.

Conclusion

AKI exhibits paramount effects on postsurgical outcomes that extend well beyond discharge from the hospital. The goal of the perioperative assessment should include the reassurance of enhancing renal function recovery among different surgeries, and optimized follow-up is warranted in attenuating the complications after postsurgical AKI has occurred.

The Japanese clinical practice guideline for acute kidney injury 2016

Acute kidney injury (AKI) is a syndrome which has a broad range of etiologic factors depending on different clinical settings. Because AKI has significant impacts on prognosis in any clinical settings, early detection and intervention is necessary to improve the outcomes of AKI patients. This clinical guideline for AKI was developed by a multidisciplinary approach with nephrology, intensive care medicine, blood purification, and pediatrics. Of note, clinical practice for AKI management which was widely performed in Japan was also evaluated with comprehensive literature search.

Acute Kidney Injury Definition and Diagnosis: A Narrative Review

Acute kidney injury (AKI) is a complex syndrome characterized by a decrease in renal function and associated with numerous etiologies and pathophysiological mechanisms. It is a common diagnosis in hospitalized patients, with increasing incidence in recent decades, and associated with poorer short- and long-term outcomes and increased health care costs. Considering its impact on patient prognosis, research has focused on methods to assess patients at risk of developing AKI and diagnose subclinical AKI, as well as prevention and treatment strategies, for which an understanding of the epidemiology of AKI is crucial. In this review, we discuss the evolving definition and classification of AKI, and novel diagnostic methods.

The Japanese Clinical Practice Guideline for acute kidney injury 2016

Acute kidney injury (AKI) is a syndrome which has a broad range of etiologic factors depending on different clinical settings. Because AKI has significant impacts on prognosis in any clinical settings, early detection and intervention are necessary to improve the outcomes of AKI patients. This clinical guideline for AKI was developed by a multidisciplinary approach with nephrology, intensive care medicine, blood purification, and pediatrics. Of note, clinical practice for AKI management which was widely performed in Japan was also evaluated with comprehensive literature search.

A worldwide multicentre evaluation of the influence of deterioration or improvement of acute kidney injury on clinical outcome in critically ill patients with and without sepsis at ICU admission: results from The Intensive Care Over Nations audit

Background

Acute kidney injury (AKI) is a common complication of critical illness and is associated with worse outcomes. However, the influence of deterioration or improvement in renal function on clinical outcomes is unclear. Using a large international database, we evaluated the prevalence and evolution of AKI over a 7-day period and its effects on clinical outcomes in septic and non-septic critically ill patients worldwide.

Methods

From the 10,069 adult intensive care unit (ICU) patients in the Intensive Care Over Nations database, all those with creatinine and urine output data were included in this substudy. Patients who developed sepsis during the ICU stay (≥ 2 days after admission) were excluded. AKI was evaluated within 72 hours after admission and before discharge/death up to day 7 according to the Acute Kidney Injury Network (AKIN) criteria.

Results

A total of 7970 patients were included, 59% of whom met AKIN criteria for AKI within the first 72 hours of the ICU stay. Twenty-four per cent of patients had sepsis on admission, of whom 68% had AKI, compared to 57% of those without sepsis on admission (p < 0.001). AKIN stage 3 (40% vs 24%, p < 0.001) and use of renal replacement therapy (20% vs 5%, p < 0.0001) were more prevalent in patients with sepsis. Patients with sepsis and AKIN stage 3 were less likely to improve to a lower stage during the 7-day follow-up period than non-septic patients with AKIN stage 3 (21% vs 32%, p < 0.0001). In-hospital mortality was related to severity of AKI and was reduced in patients in whom AKI improved compared to those who remained stable or deteriorated, but remained higher than in patients without AKI, even if there was apparent full recovery at day 7.

Conclusion

These findings illustrate the different kinetics of AKI in septic and non-septic ICU patients and emphasize the important impact of AKI on mortality rates even when there is apparent full renal recovery at day 7.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2112-z) contains supplementary material, which is available to authorized users.

Diagnosis, management, and prognosis of patients with acute kidney injury in Japanese intensive care units: The JAKID study

PURPOSE

To determine the proportion of diagnosis and outcomes of critically ill patients with acute kidney injury (AKI), and its association with mortality using the complete Kidney Disease Improving Global Outcomes (KDIGO) classification and Sepsis-3 definition.

METHODS

We conducted a multicenter prospective cohort study of 13 intensive care units (ICU) in Japan. Patients admitted to the ICUs during six months in 2016 were consecutively enrolled.

RESULTS

Among 2292 patients, AKI was diagnosed in 1024 (44.7%) patients, using the KDIGO classification. Sepsis was diagnosed in 424 patients (18.5%), of whom 281 patients (66.3%) had AKI. Septic shock was diagnosed in 166 patients (7.2%), of whom 125 patients (75.3%) had AKI. Of 1024 patients with AKI, renal replacement therapy was applied to 171 patients (16.7% of AKI) during the ICU stay. The adjusted odds ratio (aOR) of AKI to hospital mortality was 1.66 (95% confidence intervals 1.26-2.18), while that among sepsis was 0.87 (95% confidence intervals 0.55-1.37).

CONCLUSIONS

AKI accounted for >40% of ICU patients with the KDIGO classification and was associated with increased risk of hospital mortality. Septic AKI was diagnosed in three-fourths of patients with sepsis, while the impact of AKI on hospital mortality among sepsis was not observed.

AKI in the very elderly patients without preexisting chronic kidney disease: a comparison of 48-hour window and 7-day window for diagnosing AKI using the KDIGO criteria

Objectives

To compare the differences between the Kidney Disease Improving Global Outcomes (KDIGO) criteria of the 48-hour window and the 7-day window in the diagnosis of acute kidney injury (AKI) in very elderly patients, as well as the relationship between the 48-hour and 7-day windows for diagnosis and 90-day mortality.

Patients and methods

We retrospectively enrolled very elderly patients (≥75 years old) from the geriatrics department of the Chinese PLA General Hospital between January 2007 and December 2015. AKI patients were divided into 48-hour and 7-day groups by their diagnosis criteria. AKI patients were divided into survivor and nonsurvivor groups by their outcomes within 90 days after diagnosis of AKI.

Results

In total, 652 patients were included in the final analysis. The median age of the cohort was 87 (84–91) years, the majority (623, 95.6%) of whom were male. Of the 652 AKI patients, 334 cases (51.2%) were diagnosed with AKI by the 48-hour window for diagnosis, while 318 cases (48.8%) were by the 7-day window for diagnosis. The 90-day mortality was 42.5% in patients with 48-hour window AKI and 24.2% in patients with 7-day window AKI. Kaplan–Meier curves showed that 90-day mortality was lower in the 7-day window AKI group than in the 48-hour window AKI group (log rank: P<0.001). Multivariate analysis by the Cox model revealed that 48-hour window for diagnosis hazard ratio (HR=1.818; 95% CI: 1.256–2.631; P=0.002) was associated with higher 90-day mortality.

Conclusion

The 90-day mortality was higher in 48-hour window AKI than in 7-day window AKI in very elderly patients. The 48-hour KDIGO window definition may be less sensitive. The 48-hour KDIGO window definition is significantly better correlated with subsequent mortality and is, therefore, still appropriate for clinical use. Finding early, sensitive biomarkers of kidney damage is a future direction of research.

Acute kidney injury is associated with a decrease in cortical renal perfusion during septic shock

Background

Renal perfusion status remains poorly studied at the bedside during septic shock. We sought to measure cortical renal perfusion in patients with septic shock during their first 3 days of care using renal contrast enhanced ultrasound (CEUS).

Methods

We prospectively included 20 ICU patients with septic shock and 10 control patients (CL) without septic shock admitted to a surgical ICU. Cortical renal perfusion was evaluated with CEUS during continuous infusion of Sonovue (Milan, Italy) within the first 24 h (day 0), between 24 and 48 h (day 1) and after 72 h (day 3) of care. Each measurement consisted of three destruction replenishment sequences that were recorded for delayed analysis with dedicated software (Vuebox). Renal perfusion was quantified by measuring the mean transit time (mTT) and the perfusion index (PI), which is the ratio of renal blood volume (rBV) to mTT.

Results

Cortical renal perfusion was decreased in septic shock as attested by a lower PI and a higher mTT in patients with septic shock than in patients of the CL group (p = 0.005 and p = 0.03). PI values had wider range in patients with septic shock (median (min-max) of 74 arbitrary units (a.u.) (3–736)) than in patients of the CL group 228 a.u. (67–440)). Renal perfusion improved over the first 3 days with a PI at day 3 higher than the PI at day 0 (74 (22–120) versus 160 (88–245) p = 0.02). mTT was significantly higher in patients with severe acute kidney injury (AKI) (n = 13) compared with patients with no AKI (n = 7) over time (p = 0.005). The PI was not different between patients with septic shock with severe AKI and those with no AKI (p = 0.29).

Conclusions

Although hemodynamic macrovascular parameters were restored, the cortical renal perfusion can be decreased, normal or even increased during septic shock. We observed an average decrease in cortical renal perfusion during septic shock compared to patients without septic shock. The decrease in cortical renal perfusion was associated with severe AKI occurrence. The use of renal CEUS to guide renal perfusion resuscitation needs further investigation.

Renal resistive index as an early predictor and discriminator of acute kidney injury in critically ill patients; A prospective observational cohort study

Background

Acute kidney injury (AKI) complicates shock. Diagnosis is based on rising creatinine, a late phenomenon. Intrarenal vasoconstriction occurs earlier. Measuring flow resistance in the renal circulation, Renal Resistive Index (RRI), could become part of vital organ function assessment using Doppler ultrasound. Our aim was to determine whether RRI on ICU admission is an early predictor and discriminator of AKI developed within the first week.

Methods

In this prospective cohort of mixed ICU patients with and without shock, RRI was measured <24-h of admission. Besides routine variables, sublingual microcirculation and bioelectrical impedance were measured. AKI was defined by the Kidney Disease Improving Global Outcomes criteria. Uni- and multivariate regression and Receiver Operating Characteristics curve analyses were performed.

Results

Ninety-nine patients were included, median age 67 years (IQR 59–75), APACHE III score 67 (IQR 53–89). Forty-nine patients (49%) developed AKI within the first week. AKI patients had a higher RRI on admission than those without: 0.71 (0.69–0.73) vs. 0.65 (0.63–0.68), p = 0.001. The difference was significant for AKI stage 2: RRI = 0.72 (0.65–0.80) and 3: RRI = 0.74 (0.67–0.81), but not for AKI stage 1: RRI = 0.67 (0.61–0.74). On univariate analysis, RRI significantly predicted AKI 2–3: OR 1.012 (1.006–1.019); Area Under the Curve (AUC) of RRI for AKI 2–3 was 0.72 (0.61–0.83), optimal cut-off 0.74, sensitivity 53% and specificity 87%. On multivariate analysis, RRI remained significant, independent of APACHE III and fluid balance; adjusted OR: 1.008 (1.000–1.016).

Conclusions

High RRI on ICU admission was a significant predictor for development of AKI stage 2–3 during the first week. High RRI can be used as an early warning signal RRI, because of its high specificity. A combined score including RRI, APACHE III and fluid balance improved AKI prediction, suggesting that vasoconstriction or poor vascular compliance, severity of disease and positive fluid balance independently contribute to AKI development.

Trial registration

ClinicalTrials.gov NCT02558166.

Clinical Relevance and Predictive Value of Damage Biomarkers of Drug-Induced Kidney Injury

Nephrotoxin exposure accounts for up to one-fourth of acute kidney injury episodes in hospitalized patients, and the associated consequences are as severe as acute kidney injury due to other etiologies. As the use of nephrotoxic agents represents one of the few modifiable risk factors for acute kidney injury, clinicians must be able to identify patients at high risk for drug-induced kidney injury rapidly. Recently, significant advancements have been made in the field of biomarker utilization for the prediction and detection of acute kidney injury. Such biomarkers may have a role both for detection of drug-induced kidney disease and implementation of preventative and therapeutic strategies designed to mitigate injury. In this article, basic principles of renal biomarker use in practice are summarized, and the existing evidence for six markers specifically used to detect drug-induced kidney injury are outlined, including liver-type fatty acid binding protein, neutrophil gelatinase-associated lipocalin, tissue inhibitor of metalloproteinase-2 times insulin-like growth factor-binding protein 7 ([TIMP-2]·[IGFBP7]), kidney injury molecule-1 and N-acetyl-β-D-glucosaminidase. The results of the literature search for these six kidney damage biomarkers identified 29 unique articles with none detected for liver-type fatty acid binding protein and [TIMP-2]·[IGFBP7]. For three biomarkers, kidney injury molecule-1, neutrophil gelatinase-associated lipocalin and N-acetyl-β-D-glucosaminidase, the majority of the studies suggest utility in clinical practice. While many questions need to be answered to clearly articulate the use of biomarkers to predict drug-induced kidney disease, current data are promising.

Timing of Renal Replacement Therapy for Acute Kidney Injury

Acute kidney injury (AKI) is common in critically ill patients and associated with increased morbidity and mortality. With the increased use of renal replacement therapy (RRT) for severe AKI, the optimal time for initiation of RRT has become one of the most probed and debated topic in the field of nephrology and critical care. There appears to be an increased trend toward earlier initiation of RRT to avoid life-threatening complications associated with AKI. Despite the presence of a plethora of studies in this field, the lack of uniformity in study design, patient population types, definition of early and late initiation, modality of RRT, and results, the optimal time for starting RRT in AKI still remains unknown. The beneficial effects reported in observational studies have not been supported by clinical trials. Recently, 2 of the largest randomized control trials evaluating the timing of RRT in critically ill patients with AKI showed differing results. We provide an in-depth review of the available data on the timing of dialysis in patients with AKI.

Descriptive study of differences in acute kidney injury progression patterns in General and Cardiac Intensive Care Units

Background

Acute kidney injury is common in critically ill patients with detrimental effects on mortality, length of stay and post-discharge outcomes. The Acute Kidney Injury Network developed guidelines based on urine output and serum creatinine to classify patients into stages of acute kidney injury.

Methods

In this analysis we utilize the Acute Kidney Injury Network guidelines to evaluate the acute kidney injury stage in patients admitted to general and cardiac intensive care units over a period of 18 months. Acute kidney injury stage was calculated in real time hourly based on the guidelines and using these temporal stage scores calculated for the population; the prevalence and progression of acute kidney injury stage was compared between the two units. We hypothesized that the prevalence and progression of acute kidney injury stage between the two units may be different.

Results

More cardiac intensive care unit patients had no acute kidney injury (stage <1) during their intensive care unit stay but more cardiac intensive care unit patients developed acute kidney injury (stage >1), compared to the General Intensive Care Unit. Both at intensive care unit admission and discharge, more General Intensive Care Unit patients had acute kidney injury; however, the number of cardiac intensive care unit patients with acute kidney injury was three times higher at discharge than admission. Acute kidney injury developed in a different pattern in the two intensive care units over five days of intensive care unit stay. In the General Intensive Care Unit, acute kidney injury was most prevalent on second day of intensive care unit stay and in cardiac intensive care unit acute kidney injury was most prevalent on the third day of intensive care unit stay. We observed the biggest increase in new acute kidney injury in the first day of General Intensive Care Unit and second day of the cardiac intensive care unit stay.

Conclusions

The study demonstrates the different trends of acute kidney injury pattern in general and cardiac intensive care unit patient populations highlighting the earlier development of acute kidney injury on General Intensive Care Unit and more prevalence of acute kidney injury on discharge from cardiac intensive care unit.

Endothelial Damage Signals Refractory Acute Kidney Injury in Critically Ill Patients

Critically ill patients with acute kidney injury (AKI) are heterogeneous on pathophysiology and prognosis. The role of endothelial damage in the pathogenesis of refractory AKI has not been clarified. The aim was to determine if biomarkers of endothelial damage, independently of the inflammatory insult on the kidney, can predict recovery of acute kidney injury.

METHODS

From the "Procalcitonin And Survival Study" multicenter intensive care unit cohort, followed for 28 days after admission, we included patients without chronic kidney disease, who survived >24 h after admission and with plasma samples at admission available for biomarker analysis. We defined AKI by the "Kidney Disease: Improving Global Outcomes" guidelines and recovery of prior kidney function as alive for five consecutive days after admission with no need for renal replacement therapy and creatinine levels consistently below ×1.5 the level before admission. We adjusted models for age, gender, vasopressor treatment, mechanical ventilation and levels of creatinine, procalcitonin, platelets, and bilirubin at admission.

RESULTS

Of a total 213 with AKI at admission, 99 recovered prior kidney function during follow-up. Endothelial damage on admission, measured by Soluble Thrombomodulin (sTM), was the strongest predictor of a reduced chance of recovery of prior kidney function (sTM in the highest vs. three lower quartiles hazard ratio 0.39; 95% confidence interval 0.21-0.73, P = 0.003). In contrast, the degree of the initial inflammatory insult on the kidney, measured by neutrophil gelatinase-associated lipocalin (NGAL), failed to predict this outcome (NGAL in highest vs. three lower quartiles hazard ratio = 1.20; 95% CI 0.72-2.00; P = 0.48). Procalcitonin, a specific marker of bacterial infection, was also associated with the rate of recovery (PCT in highest vs. three lower quartiles hazard ratio = 0.59; 95% CI 0.36-0.98; P = 0.04).

CONCLUSION

AKI patients with high levels of sTM had a reduced chance of recovering prior renal function. Our findings support disintegration of the endothelium as a critical point in the pathogenesis of AKI that is refractory to treatment.

Epidemiological characteristics of and risk factors for patients with postoperative acute kidney injury: a multicenter prospective study in 30 Chinese intensive care units

BACKGROUND

Although there were studies to investigate the risk factors for acute kidney injury (AKI) after surgery, most of them focused on one specific type of surgeries. The risk factors for postoperative AKI in patients undergoing all surgeries in intensive care units (ICU) have not been reported.

METHODS

Data from 1731 patients undergoing surgery in 30 ICUs of 28 tertiary hospitals in Beijing from March to August 2012 were prospectively collected. AKI was defined and staged by the KDIGO criteria. Multivariate logistic regression analysis was performed to assess independent risk factors for postoperative AKI.

RESULTS

Postoperative AKI occurred in 44.8% of patients (stage 1 54.8%; stage 2 21.9%, stage 3 23.3%). Cardiovascular surgery was identified as an independent factor for postoperative AKI as well as emergency surgery [odds ratio (OR) 1.403], nephrotoxic drugs (OR 1.303), APACHE II score (OR 1.055), SOFA score (OR 1.115), duration for positive fluid balance (OR 1.165), use of diuretics (OR 2.293), sepsis (OR 1.501), and CKD (OR 4.517). AKI stage 3 versus stages 1-2 was associated with higher mortality in ICU, hospital, and 28-day follow-up after cardiovascular, abdominal, limb, and chest surgeries, while this was not observed after neurosurgery or other surgeries.

CONCLUSION

Risk factors for AKI in ICU patients after different types of surgery were identified. This might be the first step to reduce the high incidence of AKI after surgery. The presence of AKI in ICU patients was associated with higher mortality after most types of surgery, but not after neurosurgery.

TRIAL REGISTRATION

ChiCTR-ONC-11001875.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

BACKGROUND AND PURPOSE

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 and published in the Journal of JSICM, [2017; Volume 24 (supplement 2)] 10.3918/jsicm.24S0001 and Journal of Japanese Association for Acute Medicine [2017; Volume 28, (supplement 1)] http://onlinelibrary.wiley.com/doi/10.1002/jja2.2017.28.issue-S1/issuetoc.This abridged English edition of the J-SSCG 2016 was produced with permission from the Japanese Association of Acute Medicine and the Japanese Society for Intensive Care Medicine.

METHODS

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ) and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (> 66.6%) majority vote of each of the 19 committee members.

RESULTS

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation, and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty-seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for five CQs.

CONCLUSIONS

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

The predictive value of NT-proBNP and hs-TnT for risk of death in cardiac surgical patients

BACKGROUND

European System for Cardiac Operative Risk Evaluation II (EuroSCORE II) is used for risk stratification before cardiac surgery, but whether N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hs-TnT) may add prognostic information to EuroSCORE II is not known.

METHODS

Preoperative (n=640) and postoperative (n=629) blood samples were available from cardiac surgical patients with 961-day follow-up (FINNAKI Heart study; cohort #1). The accuracy of a parsimonious risk model with NT-proBNP measurements was also tested in 90 patients with respiratory failure after cardiac surgery (FINNALI study; cohort #2).

RESULTS

Sixty-one patients (9.5%) died during follow-up in cohort #1. Preoperative NT-proBNP and hs-TnT concentrations correlated (rho=0.58; p<0.001) and were higher in non-survivors compared to survivors: median 2027 (Q1-3 478-5387) vs. 373 (134-1354) ng/L [NT-proBNP] and 39 (16-191) vs. 13 (8-32) ng/L [hs-TnT]; p<0.001 for both. Preoperative NT-proBNP concentrations were associated with time to death after adjustment for EuroSCORE II (HR [_lnNT-proBNP] 1.33 [95% CI 1.08-1.64]), p=0.008 and reclassified patients on top of EuroSCORE II (net reclassification index 0.39 [95% CI 0.14-0.64], p=0.003). Pre- and postoperative NT-proBNP concentrations were closely correlated (rho=0.80, p<0.001) and postoperative NT-proBNP concentrations were also associated with long-term mortality after adjustment for EuroSCORE II. A parsimonious risk model that included age, creatinine clearance, chronic pulmonary disease, and NT-proBNP measurements provided comparable prognostic accuracy as EuroSCORE II in cohort #1 and #2 for risk of long-term mortality. hs-TnT measurements did not add to NT-proBNP measurements CONCLUSION: NT-proBNP measurements could improve and simplify risk prediction in cardiac surgical patients.

Incidence, Risk Factors, and Outcome of Acute Kidney Injury in Neurocritical Care

PURPOSE

Acute kidney injury (AKI) is a severe complication in medical and surgical intensive care units accounting for a high morbidity and mortality. Incidence, risk factors, and prognostic impact of this deleterious condition are well established in this setting. Data concerning the neurocritically ill patients is scarce. Therefore, aim of this study was to determine the incidence of AKI and elucidate risk factors in this special population.

METHODS

Patients admitted to a specialized neurocritical care unit between 2005 and 2011 with a length of stay above 48 hours were analyzed retrospectively for incidence, cause, and outcome of AKI (AKI Network-stage ≥2).

RESULTS

The study population comprised 681 neurocritically ill patients from a mixed neurosurgical and neurological intensive care unit. The prevalence of chronic kidney disease (CKD) was 8.4% (57/681). Overall incidence of AKI was 11.6% with 36 (45.6%) patients developing dialysis-requiring AKI. Sepsis was the main cause of AKI in nearly 50% of patients. Acute kidney injury and renal replacement therapy are independent predictors of worse outcome (hazard ratio [HR]: 3.704; 95% confidence interval [CI]: 1.867-7.350; P < .001; and HR: 2.848; CI: 1.301-6.325; P = .009). Chronic kidney disease was the strongest independent risk factor (odds ratio: 12.473; CI: 5.944-26.172; P < .001), whereas surgical intervention or contrast agents were not associated with AKI.

CONCLUSIONS

Acute kidney injury in neurocritical care has a high incidence and is a crucial risk factor for mortality independently of the underlying neurocritical condition. Sepsis is the main cause of AKI in this setting. Therefore, careful prevention of infectious complications and considering CKD in treatment decisions may lower the incidence of AKI and hereby improve outcome in neurocritical care.

Phenotyping of Acute Kidney Injury: Beyond Serum Creatinine

Acute kidney injury (AKI) is a common complication in hospitalized patients and is associated with adverse short- and long-term outcomes. AKI is diagnosed by serum creatinine (SCr)-based consensus definitions that capture an abrupt decrease in glomerular filtration rate associated with AKI. However, SCr-based AKI definitions lack sensitivity and specificity for diagnosing structural kidney injury. Moreover, AKI is a heterogeneous condition consisting of distinct phenotypes based on its etiology, prognosis, and molecular pathways, and that may potentially require different therapies. SCr-based AKI definitions provide no information on these AKI phenotypes. This review highlights traditional and novel tools that overcome the limitations of SCr-based AKI definitions to improve AKI phenotyping.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

Background and Purpose

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 in Japanese. An English-language version of these guidelines was created based on the contents of the original Japanese-language version.

Methods

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ), and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (>66.6%) majority vote of each of the 19 committee members.

Results

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for 5 CQs.

Conclusions

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

Timing of renal replacement therapy and long-term risk of chronic kidney disease and death in intensive care patients with acute kidney injury

Background

The optimal time to initiate renal replacement therapy (RRT) in intensive care unit (ICU) patients with acute kidney injury (AKI) is unclear. We examined the impact of early RRT on long-term mortality, risk of chronic kidney disease (CKD), and end-stage renal disease (ESRD).

Methods

This cohort study included all adult patients treated with continuous RRT in the ICU at Aarhus University Hospital, Skejby, Denmark (2005–2015). Data were obtained from a clinical information system and population-based registries. Early treatment was defined as RRT initiation at AKI stage 2 or below, and late treatment was defined as RRT initiation at AKI stage 3. Inverse probability of treatment (IPT) weights were computed from propensity scores. The IPT-weighted cumulative risk of CKD (estimated glomerular filtration rate < 60 ml/minute/1.73 m²), ESRD, and mortality was estimated and compared using IPT-weighted Cox regression.

Results

The mortality, CKD, and ESRD analyses included 1213, 303, and 617 patients, respectively. The 90-day mortality in the early RRT group was 53.6% compared with 46.0% in the late RRT group (HR 1.24, 95% CI 1.03–1.48). The 90-day to 5-year mortality was 37.7% and 41.5% in the early and late RRT groups, respectively (HR 0.95, 95% CI 0.70–1.29). The 5-year risk of CKD was 35.9% in the early RRT group and 44.9% in the late RRT group (HR 0.74, 95% CI 0.46–1.18). The 5-year risk of ESRD was 13.3% in the early RRT group and 16.7% in the late RRT group (HR 0.79, 95% CI 0.47–1.32).

Conclusions

Early initiation was associated with increased 90-day mortality. In patients surviving to day 90, early initiation was not associated with a major impact on long-term mortality or risk of CKD and ESRD. Despite potential residual confounding due to the observational design, our findings do not support that early RRT initiation is superior to late initiation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1903-y) contains supplementary material, which is available to authorized users.

Mortality risk factors in elderly patients in intensive care without limitation of therapeutic effort

OUTCOME

To determine mortality prognostic factors in elderly patients who are admitted to intensive care units (ICUs) due to acute critical illness.

DESIGN

A prospective cohort study was carried out.

SETTING

A polyvalent Intensive Care Unit at a University Hospital in Argentina.

PATIENTS OR PARTICIPANTS

We included 249 patients over 65years of age who were consecutively admitted to the ICU and required mechanical ventilation for more than 48hours, between January 2011 and December 2012. Patients with degenerative neurological disease, limitation of therapeutic effort or on chronic mechanical ventilation were excluded.

PRINCIPAL VARIABLES OF INTEREST

In-hospital mortality, comorbidity (Charlson index), APACHEII score, and pre-acute illness status were recorded: nutritional status (subjective global assessment), functionality (activities of daily living [ADL] and Barthel index), cognitive abilities (Short Reporting Questionnaire on Cognitive Decline in the Elderly [S_IQCODE]) and quality of life (EQ-5D).

RESULTS

The in-hospital mortality rate was 52%. Logistic regression analysis, after adjusting for APACHEII score and age, identified the following independent variables associated to mortality: male gender (OR: 2.46, 95%CI: 1.37-4.42), moderate malnutrition (OR: 2.07, 95%CI: 1.09-3.94), severe malnutrition (OR: 2.20, 95%CI: 1.06-4.59), and ADL<6 (OR: 2.35, 95%CI: 1.16-4.75).

CONCLUSIONS

In our study, chronological age was not associated to in-hospital mortality. However, loss of functional independence (assessed by ADL) and malnourishment were shown to be strong prognostic factors; knowing these baseline characteristics from ICU admission would be useful when making decisions regarding the intensity of treatment.

Assessment of plasma endostatin to predict acute kidney injury in critically ill patients

BACKGROUND

We evaluated whether plasma endostatin predicts acute kidney injury (AKI), need for renal replacement therapy (RRT), or death.

METHODS

Prospective, observational, multicenter study from 1 September 2011 to 1 February 2012 with data from 17 intensive care units (ICUs) in Finland.

RESULTS

A total of 1112 patients were analyzed. We measured plasma endostatin within 2 h of ICU admission. Early AKI (KDIGO stage within 12 h of ICU admission) was found in 20% of the cohort, and 18% developed late AKI (KDIGO criteria > 12 h from ICU admission). Median (IQR) admission endostatin was higher in the early AKI group, 29 (19.1, 41.9) ng/ml as compared to 22.4 (16.1, 30.1) ng/ml for the late AKI group, and 18 (14.0, 23.6) ng/ml for non-AKI patients (P < 0.001). Endostatin level increased with increasing KDIGO stage. Significantly higher endostatin levels were found in patients with sepsis as compared to those without. Predictive properties for AKI, RRT, and mortality were low with corresponding areas under the receiver operating characteristic curve (AUC) of 0.62, 0.67, and 0.59. Sensitivity analyses among patients with chronic kidney disease or sepsis did not improve the predictive ability of endostatin. Adding endostatin to a clinical AKI prediction model (illness severity score, urine output, and age) insignificantly changed the AUC from 0.67 to 0.70 (P = 0.14).

CONCLUSIONS

Endostatin increases with AKI severity but has limited value as a predictor of AKI, RRT and 90-day mortality in patients admitted to ICU. Moreover, endostatin does not improve AKI risk prediction when added to a clinical risk model.

Risk Factor Analysis for AKI Including Laboratory Indicators: a Nationwide Multicenter Study of Hospitalized Patients

BACKGROUND/AIMS

Risk factor studies for acute kidney injury (AKI) in China are lacking, especially those regarding non-traditional risk factors, such as laboratory indicators.

METHODS

All adult patients admitted to 38 tertiary and 22 secondary hospitals in China in any one month between July and December 2014 were surveyed. AKI patients were screened according to the Kidney Disease: Improving Global Outcomes' definition of AKI. Logistic regression was used to analyze the risk factors for AKI, and Cox regression was used to analyze the risk of in-hospital mortality for AKI patients; additionally, a propensity score analysis was used to reconfirm the risk factors among laboratory indicators for mortality.

RESULTS

The morbidity of AKI was 0.97%. Independent risk factors for AKI were advancing age, male gender, hypertension, and chronic kidney disease. All-cause mortality was 16.5%. The predictors of mortality in AKI patients were advancing age, tumor, higher uric acid level and increases in Acute Physiologic Assessment and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores. The hazard ratio (HR) for mortality with uric acid levels > 9.1 mg/dl compared with ≤ 5.2 mg/dl was 1.78 (95% CI: 1.23 to 2.58) for the AKI patients as a group, and was 1.73 (95% CI: 1.24 to 2.42) for a propensity score-matched set.

CONCLUSION

In addition to traditional risk factors, uric acid level is an independent predictor of all-cause mortality after AKI.

Heparin-binding protein (HBP) improves prediction of sepsis-related acute kidney injury

BACKGROUND

Sepsis-related acute kidney injury (AKI) accounts for major morbidity and mortality among the critically ill. Heparin-binding protein (HBP) is a promising biomarker in predicting development and prognosis of severe sepsis and septic shock that has recently been proposed to be involved in the pathophysiology of AKI. The objective of this study was to investigate the added predictive value of measuring plasma HBP on admission to the intensive care unit (ICU) regarding the development of septic AKI.

METHODS

We included 601 patients with severe sepsis or septic shock from the prospective, observational FINNAKI study conducted in seventeen Finnish ICUs during a 5-month period (1 September 2011-1 February 2012). The main outcome measure was the development of KDIGO AKI stages 2-3 from 12 h after admission up to 5 days. Statistical analysis for the primary endpoint included construction of a clinical risk model, area under the receiver operating curve (ROC area), category-free net reclassification index (cfNRI) and integrated discrimination improvement (IDI) with 95% confidence intervals (95% CI).

RESULTS

Out of 511 eligible patients, 101 (20%) reached the primary endpoint. The addition of plasma HBP to a clinical risk model significantly increased ROC area (0.82 vs. 0.78, p = 0.03) and risk classification scores: cfNRI 62.0% (95% CI 40.5-82.4%) and IDI 0.053 (95% CI 0.029-0.075).

CONCLUSIONS

Plasma HBP adds predictive value to known clinical risk factors in septic AKI. Further studies are warranted to compare the predictive performance of plasma HBP to other novel AKI biomarkers.

Utility of electronic AKI alerts in intensive care: A national multicentre cohort study

BACKGROUND

Electronic AKI alerts highlight changes in serum creatinine compared to the patient's own baseline. Our aim was to identify all AKI alerts and describe the relationship between electronic AKI alerts and outcome for AKI treated in the Intensive Care Unit (ICU) in a national multicentre cohort.

METHODS

A prospective cohort study was undertaken between November 2013 and April 2016, collecting data on electronic AKI alerts issued.

RESULTS

10% of 47,090 incident AKI alerts were associated with ICU admission. 90-day mortality was 38.2%. Within the ICU cohort 48.8% alerted in ICU. 51.2% were transferred to ICU within 7days of the alert, of which 37.8% alerted in a hospital setting (HA-AKI) and 62.2% in a community setting (CA-AKI). Mortality was higher in patients transferred to ICU following the alert compared to those who had an incident alert on the ICU (p<0.001), and was higher in HA-AKI (45.3%) compared to CA-AKI (39.5%) (35.0%, p=0.01). In the surviving patients, the proportion of patient recovering renal function following, was significantly higher in HA-AKI alerting (84.2%, p=0.004) and CA-AKI alerting patients (87.6%, p<0.001) compared to patients alerting on the ICU (78.3%).

CONCLUSION

The study provides a nationwide characterisation of AKI in ICU highlighting the high incidence and its impact on patient outcome. The data also suggests that within the cohort of AKI patients treated in the ICU there are significant differences in the presentation and outcome between those patients that require transfer to the ICU after AKI is identified and those who develop AKI following ICU admission. Moreover, the study demonstrates that using AKI e-alerts provides a centralised resource which does not rely on clinical diagnosis of AKI or coding, resulting in a robust data set which can be used to define the incidence and outcome of AKI in the ICU setting.

Epidemiology of acute kidney injury and chronic kidney disease in the intensive care unit

OBJECTIVE

To describe the epidemiology of acute kidney injury, its relationship to chronic kidney disease, and the factors associated with its incidence.

METHODS

A cohort study and follow-up were conducted in an intensive care unit in Montevideo, Uruguay. We included patients admitted between November 2014 and October 2015 who were older than 15 years of age and who had at least two measurements of serum creatinine. We excluded patients who were hospitalized for less than 48 hours, patients who died at the time of hospitalization, and patients with chronic renal disease who were on hemodialysis or peritoneal dialysis. There were no interventions. Acute kidney injury was defined according to the criteria set forth in Acute Kidney Injury Disease: Improving Global Outcomes, and chronic kidney disease was defined according to the Chronic Kidney Disease Work Group.

RESULTS

We included 401 patients, 56.6% male, median age of 68 years (interquartile range (IQR) 51-79 years). The diagnosis at admission was severe sepsis 36.3%, neurocritical 16.3%, polytrauma 15.2%, and other 32.2%. The incidence of acute kidney injury was 50.1%, and 14.1% of the patients suffered from chronic kidney disease. The incidence of acute septic kidney injury was 75.3%. Mortality in patients with or without acute kidney injury was 41.8% and 14%, respectively (p < 0.001). In the multivariate analysis, the most significant variables for acute kidney injury were chronic kidney disease (odds ratio (OR) 5.39, 95%CI 2.04 - 14.29, p = 0.001), shock (OR 3.94, 95%CI 1.72 - 9.07, p = 0.001), and severe sepsis (OR 7.79, 95%CI 2.02 - 29.97, p = 0.003).

CONCLUSION

The incidence of acute kidney injury is high mainly in septic patients. Chronic kidney disease was independently associated with the development of acute kidney injury.

Renal ultrasound provides low utility in evaluating cardiac surgery associated acute kidney injury

BACKGROUND

Renal ultrasonography is part of the algorithm in assessing acute kidney injury (AKI). The purpose of this study was to assess the clinical utility of renal US in postoperative cardiac patients who develop AKI.

METHODS

We conducted a retrospective study of 90 postoperative cardiac surgery patients at a single institution from 1/19/2010 to 3/19/2016 who underwent renal US for AKI. We reviewed provider documentation to determine whether renal US changed management. We defined change as: administration of crystalloid or colloid, addition of inotropic or vasopressor, or procedural interventions on the renal system.

RESULTS

Mean age of study patients was 68 ± 13 years. 48/90 patients (53.3%) had pre-existing chronic kidney disease of varying severity. 48 patients (53.3%) had normal renal US with incidental findings and 31 patients (34.4%) had US evidence of medical kidney disease. 10 patients (11.1%) had limited US results due to poor visualization and 1 patient (1.1%) had mild right-sided hydronephrosis. No patients were found to have obstructive uropathy or renal artery stenosis. Clinical management was altered in only 4/90 patients (4.4%), which included 3 patients that received a fluid bolus and 1 patient that received a fluid bolus and inotropes. No vascular or urologic procedures resulted from US findings.

CONCLUSION

Although renal ultrasound is often utilized in the work-up of AKI, our study shows that renal US provides little benefit in managing postoperative cardiac patients. This diagnostic modality should be scrutinized rather than viewed as a universal measure in the cardiac surgery population.

A decrease in serum creatinine after ICU admission is associated with increased mortality

Background

The elevation of serum creatinine (SCr), acute kidney injury (AKI), is associated with an increase of mortality in critically ill patients. However, it is uncertain whether a decrease in SCr in the intensive care unit (ICU) has an effect on outcomes.

Methods

In a retrospective study, we enrolled 486 patients who had been admitted to an urban tertiary center ICU between Jan 2014 and Dec 2014. The effect of changes in SCr after ICU admission on 90 day mortality was analyzed. Patients were classified into 3 groups based on change in SCr after ICU admission: a stable SCr group (Δ SCr < 0.3mg/dL during ICU stay), a decreased SCr group (Δ SCr ≥ -0.3 mg/dL during ICU stay) and an increased SCr group with criteria based on the KDIGO AKI criteria.

Results

In total, 486 patients were identified. SCr decreased in 123 (25.3%) patients after ICU admission. AKI developed in 125 (24.4%) patients. The overall 90-day mortality rate was 29.0%. In a Kaplan-Meyer analysis, the mortality of the AKI group was higher than that of other groups (p<0.0001). Patients with a decrease in SCr had a higher mortality rate than those with stable SCr (p<0.0001). A Cox analysis showed that both a decrease in SCR (HR, 3.56; 95% CI, 1.59–7.97; p = 0.002) and an increase in SCr (AKI stage 1, HR, 9.35; 95% CI, 4.18–20.9; p<0.0001; AKI stage 2, HR, 11.82; 95% CI, 3.85–36.28; p<0.0001; AKI stage 3, HR, 17.41; 95% CI, 5.50–55.04; p<0.0001) were independent risk factors for death compared to stable SCr.

Conclusion

Not only an increase in SCr, but also a decrease in SCr was associated with mortality in critically ill patients.

A new scoring model for the prediction of mortality in patients with acute kidney injury

Currently, little information is available to stratify the risks and predict acute kidney injury (AKI)-associated death. In this present cross-sectional study, a novel scoring model was established to predict the probability of death within 90 days in patients with AKI diagnosis. For establishment of predictive scoring model, clinical data of 1169 hospitalized patients with AKI were retrospectively collected, and 731 patients of them as the first group were analyzed by the method of multivariate logistic regression analysis to create a scoring model and further predict patient death. Then 438 patients of them as the second group were used for validating this prediction model according to the established scoring method. Our results showed that Patient’s age, AKI types, respiratory failure, central nervous system failure, hypotension, and acute tubular necrosis-individual severity index (ATN-ISI) score are independent risk factors for predicting the death of AKI patients in the created scoring model. Moreover, our scoring model could accurately predict cumulative AKI and mortality rate in the second group. In conclusion, this study identified the risk factors of 90-day mortality for hospitalized AKI patients and established a scoring model for predicting 90-day prognosis, which could help to interfere in advance for improving the quality of life and reduce mortality rate of AKI patients.

Definition, Management, and Outcomes of Acute Kidney Injury: An International Survey of Nephrologists

Background

Acute kidney injury (AKI) is a complex disease burdened by uncertainties of definition, management strategies, and prognosis. This study explores the relationship between demographic characteristics of nephrologists and their perceptions about the definition, management, and follow-up of AKI.

Methods

We developed a Web-based survey, the International Survey on Acute Kidney Injury (ISAKI), consisting of 29 items in 4 categories: (1) demographic and practice characteristics, (2) definition of AKI, (3) management of renal replacement therapy (RRT) in AKI, and (4) sequelae of AKI. A multivariable stepwise logistic regression model was used to examine relationships between the dependent variables and the demographic characteristics of the respondents.

Results

Responses from 743 nephrologists from 90 countries were analyzed. The majority (60%) of respondents reported using RIFLE and/or AKIN criteria regularly to define AKI, although US nephrologists were less likely to do so (OR: 0.58; 95% CI: 0.42-0.85). The most common initial RRT modality was intermittent hemodialysis (63.5%), followed by continuous RRT (23.8%). Faculty affiliation was associated with a higher likelihood of using a dialysis schedule of ≥4 times a week (OR: 1.75; 95% CI: 1.20-2.55). The respondents believed that a single episode of AKI increases the likelihood of development of chronic kidney disease (CKD) (55%), subsequent AKI (36%), and rapid progression of preexisting CKD (87%). US nephrologists were less likely to recommend follow-up after resolution of AKI (OR: 0.15; 95% CI: 0.07-0.33).

Conclusions

Our findings highlight the need for a widely accepted consensus definition of AKI, a uniform approach to management, and improved follow-up after resolution of AKI episodes.

The effect of low-dose furosemide in critically ill patients with early acute kidney injury: A pilot randomized blinded controlled trial (the SPARK study)

PURPOSE

Furosemide is commonly prescribed in acute kidney injury (AKI). Prior studies have found conflicting findings on whether furosemide modifies the course and outcome of AKI.

METHODS

Pilot multi-center randomized blinded placebo-controlled trial in adult patients with AKI admitted to three intensive care units. Participants were randomly allocated to furosemide bolus and infusion or 0.9% saline placebo. Primary endpoint was worsening AKI, defined by the RIFLE criteria. Secondary endpoints were kidney recovery, renal replacement therapy (RRT) and adverse events.

RESULTS

The trial was terminated after enrollment of 73 participants (37 to furosemide and 36 to placebo). Mean (SD) age was 61.7 (14.3), 79.5% were medical admissions, mean (SD) APACHE II score was 26.6 (7.8), 90.4% received mechanical ventilation and 61.6% received vasoactives. Groups were similar at baseline. No differences were found in the proportion with worsening AKI (43.2% vs. 37.1%, p=0.6), kidney recovery (29.7% vs. 42.9%, p=0.3), or RRT (27.0% s. 28.6%, p=0.8). Adverse events, mostly electrolyte abnormalities, were more common in furosemide-treated patients (p<0.001). Protocol deviations were common, due often to supplementary furosemide.

CONCLUSIONS

In this pilot trial, furosemide did not reduce the rate of worsening AKI, improve recovery or reduce RRT; however, was associated with greater electrolyte abnormalities.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00978354 registered September 9, 2014.

Outcomes in patients with acute kidney injury reviewed by Critical Care Outreach: What is the role of the National Early Warning Score?

Introduction

This study investigated outcomes in critically unwell acute kidney injury patients and the role of the National Early Warning Score and other factors in identifying patients who experience negative outcomes.

Methods

Retrospective cohort study investigating 64 patients seen by Critical Care Outreach between November 2014 and February 2015. Mortality at one year was analysed using multivariate regression; all other statistical tests were non-parametric.

Results

Forty-four per cent of patients required escalation to higher level care, 56% failed to survive beyond one year and 30% of those who did survive had a deterioration in renal function. Previous acute kidney injury significantly predicted mortality but the National Early Warning Score did not. A subgroup of patients developed Stage 3 acute kidney injury before a rise in National Early Warning Score.

Conclusions

Acute kidney injury in the Critical Care Outreach patient population is associated with high morbidity and mortality. Previous acute kidney injury and acute kidney injury stage may be superior to the National Early Warning Score at identifying patients in need of Critical Care Outreach review.