Comparison of the RIFLE, AKIN and KDIGO criteria to predict mortality in critically ill patients

Urinary oxygen tension and its role in predicting acute kidney injury: A narrative review

Acute kidney injury occurs frequently in the perioperative setting. The renal medulla often endures hypoxia or hypoperfusion and is susceptible to the imbalance between oxygen supply and demand due to the nature of renal blood flow distribution and metabolic rate in the kidney. The current available evidence demonstrated that the urine oxygen pressure is proportional to the variations of renal medullary tissue oxygen pressure. Thus, urine oxygenation can be a candidate for reflecting the change of oxygen in the renal medulla. In this review, we discuss the basic physiology of acute kidney injury, as well as techniques for monitoring urine oxygen tension, confounding factors affecting the reliable measurement of urine oxygen tension, and its clinical use, highlighting its potential role in early detection and prevention of acute kidney injury.

Prevalence of acute kidney injury among dengue cases: a systematic review and meta-analysis

Numerous studies have shown a correlation between dengue virus (DENV) infection and kidney disease. However, there is no existing meta-analysis on the prevalence of kidney diseases in the dengue population. A thorough systematic review and meta-analysis were undertaken to determine the prevalence of renal problems in people with DENV infection in order to fill this knowledge gap. A rigorous electronic literature search was carried out up to 25 January 2023 in a number of databases, including ProQuest, EBSCOhost, Scopus, PubMed and Web of Science. The search aimed to find articles that reported on the prevalence of kidney diseases in patients with DENV infection. Using the modified Newcastle-Ottawa Scale, the quality of the included studies was assessed. The meta-analysis included a total of 37 studies with 21 764 participants reporting on the prevalence of acute kidney injury (AKI) in individuals with DENV infection. The pooled prevalence of AKI in dengue patients was found to be 8% (95% confidence interval 6 to 11), with high heterogeneity across studies. The studies included are of moderate quality. The study revealed a high AKI prevalence in dengue patients, underlining the need for regular renal examination to detect AKI early and reduce hospitalization risk. Further research is needed to understand the dengue-kidney relationship and develop effective management strategies.

Differential effect on mortality of the timing of initiation of renal replacement therapy according to the criteria used to diagnose acute kidney injury: an IDEAL-ICU substudy

BACKGROUND

This substudy of the randomized IDEAL-ICU trial assessed whether the timing of renal replacement therapy (RRT) initiation has a differential effect on 90-day mortality, according to the criteria used to diagnose acute kidney injury (AKI), in patients with early-stage septic shock.

METHODS

Three groups were considered according to the criterion defining AKI: creatinine elevation only (group 1), reduced urinary output only (group 2), creatinine elevation plus reduced urinary output (group 3). Primary outcome was 90-day all-cause death. Secondary endpoints were RRT-free days, RRT dependence and renal function at discharge. We assessed the interaction between RRT strategy (early vs. delayed) and group, and the association between RRT strategy and mortality in each group by logistic regression.

RESULTS

Of 488 patients enrolled, 205 (42%) patients were in group 1, 174 (35%) in group 2, and 100 (20%) in group 3. The effect of RRT initiation strategy on 90-day mortality across groups showed significant heterogeneity (adjusted interaction p = 0.021). Mortality was 58% vs. 42% for early vs. late RRT initiation, respectively, in group 1 (p = 0.028); 57% vs. 67%, respectively, in group 2 (p = 0.18); and 58% vs. 55%, respectively, in group 3 (p = 0.79). There was no significant difference in secondary outcomes.

CONCLUSION

The timing of RRT initiation has a differential impact on outcome according to AKI diagnostic criteria. In patients with elevated creatinine only, early RRT initiation was associated with significantly increased mortality. In patients with reduced urine output only, late RRT initiation was associated with a nonsignificant, 10% absolute increase in mortality.

Kidney Transplantation From Donors With Acute Kidney Injury: Are the Concerns Justified? A Systematic Review and Meta-Analysis

Renal transplantation improves quality of life and prolongs survival in patients with end-stage kidney disease, although challenges exist due to the paucity of suitable donor organs. This has been addressed by expanding the donor pool to include AKI kidneys. We aimed to establish whether transplanting such kidneys had a detrimental effect on graft outcome. The primary aim was to define early outcomes: delayed graft function (DGF) and primary non-function (PNF). The secondary aims were to define the relationship to acute rejection, allograft survival, eGFR and length of hospital stay (LOS). A systematic literature review and meta-analysis was conducted on the studies reporting the above outcomes from PubMed, Embase, and Cochrane Library databases. This analysis included 30 studies. There is a higher risk of DGF in the AKI group (OR = 2.20, p < 0.00001). There is no difference in the risk for PNF (OR 0.99, p = 0.98), acute rejection (OR 1.29, p = 0.08), eGFR decline (p = 0.05) and prolonged LOS (p = 0.11). The odds of allograft survival are similar (OR 0.95, p = 0.54). Transplanting kidneys from donors with AKI can lead to satisfactory outcomes. This is an underutilised resource which can address organ demand.

Acute Kidney Injury Classifications in the Prediction of In-hospital Mortality and Renal Function Non-recovery

Background

In the last two decades diagnostic criteria for acute kidney injury (AKI) were developed: Risk, Injury, Failure, Loss of Kidney Function, End-Stage Kidney Disease (RIFLE), Acute Kidney Injury Network (AKIN), and Kidney Disease: Improving Global Outcomes (KDIGO) classifications.

Objective

The study aimed to determine the incidence of AKI based on the RIFLE, AKIN, and KDIGO criteria, as well as analyze their predictive value for mortality and renal function outcome.

Methods

This was a single-center prospective study of patients diagnosed with AKI. Acute kidney injury was defined and classified according to the RIFLE, AKIN, and KDIGO criteria. The outcomes were renal function outcome and in-hospital mortality.

Results

The incidence rates of AKI based on the RIFLE, AKIN, and KDIGO criteria were 13.4%, 14-36%, and 14.64%, respectively. Multiple regression analysis showed that higher stages of AKI according to the KDIGO criteria were independently associated with non-recovery of renal function (p=0.011). However, the predictive ability of RIFLE, AKIN and KDIGO classifications for renal function recovery was poor (Area Under the Receiver Operating Characteristics-AUROC=0.599, AUROC=0.637, AUROC=0.659, respectively). According to the RIFLE and AKIN criteria, in-hospital mortality was statistically significantly higher in stage Failure/3 (p=0.0403 and p=0.0329, respectively) compared to stages Risk/1 and Injury/2. Receiver Operating Characteristics (ROC) analysis showed that all three classifications had poor predictive ability for in-hospital mortality (AUROC=0.675, AUROC=0.66, AUROC=0.681).

Conclusions

KDIGO classification is an independent predictor of renal function non-recovery. However, by ROC analysis, all three classifications have poor predictive ability for renal function outcome and mortality.

Ambiguous definitions for baseline serum creatinine affect acute kidney diagnosis at the emergency department

Background

Acute kidney injury (AKI) incidence is increasing, however AKI is often missed at the emergency department (ED). AKI diagnosis depends on changes in kidney function by comparing a serum creatinine (SCr) measurement to a baseline value. However, it remains unclear to what extent different baseline values may affect AKI diagnosis at ED.

Methods

Routine care data from ED visits between 2012 and 2019 were extracted from the Utrecht Patient Oriented Database. We evaluated baseline definitions with criteria from the RIFLE, AKIN and KDIGO guidelines. We evaluated four baseline SCr definitions (lowest, most recent, mean, median), as well as five different time windows (up to 365 days prior to ED visit) to select a baseline and compared this to the first measured SCr at ED. As an outcome, we assessed AKI prevalence at ED.

Results

We included 47,373 ED visits with both SCr-ED and SCr-BL available. Of these, 46,100 visits had a SCr-BL from the − 365/− 7 days time window. Apart from the lowest value, AKI prevalence remained similar for the other definitions when varying the time window. The lowest value with the − 365/− 7 time window resulted in the highest prevalence (21.4%). Importantly, applying the guidelines with all criteria resulted in major differences in prevalence ranging from 5.9 to 24.0%.

Conclusions

AKI prevalence varies with the use of different baseline definitions in ED patients. Clinicians, as well as researchers and developers of automatic diagnostic tools should take these considerations into account when aiming to diagnose AKI in clinical and research settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02581-x.

Association of Oliguria With Acute Kidney Injury Diagnosis, Severity Assessment, and Mortality Among Patients With Critical Illness

Importance

The current definition and staging of acute kidney injury (AKI) considers alterations in serum creatinine (sCr) level and urinary output (UO). However, the relevance of oliguria-based criteria is disputed.

Objective

To determine the contribution of oliguria, as defined by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria, to AKI diagnosis, severity assessment, and short- and long-term outcomes.

Design, Setting, and Participants

This cohort study included adult patients admitted to a multidisciplinary intensive care unit from January 1, 2010, to June 15, 2020. Patients receiving long-term dialysis and those who declined consent were excluded. Daily sCr level and hourly UO measurements along with sociodemographic characteristics and severity scores were extracted from electronic medical records. Long-term mortality was assessed by cross-referencing the database with the Swiss national death registry. The onset and severity of AKI according to the KDIGO classification was determined using UO and sCr criteria separately, and their agreement was assessed.

Main Outcomes and Measures

Using a multivariable model accounting for baseline characteristics, severity scores, and sCr stages, the association of UO criteria with 90-day mortality was evaluated. Sensitivity analyses were conducted to assess how missing sCr, body weight, and UO values, as well as different sCr baseline definitions and imputations methods, would affect the main results.

Results

Among the 15 620 patients included in the study (10 330 men [66.1%] with a median age of 65 [IQR, 53-75] years, a median Simplified Acute Physiology Score II score of 40.0 [IQR, 30.0-53.0], and a median follow-up of 67.0 [IQR, 34.0-100.0] months), 12 143 (77.7%) fulfilled AKI criteria. Serum creatinine and UO criteria had poor agreement on AKI diagnosis and staging (Cohen weighted κ, 0.36; 95% CI, 0.35-0.37; P < .001). Compared with the isolated use of sCr criteria, consideration of UO criteria enabled identification of AKI in 5630 patients (36.0%). Those patients had a higher 90-day mortality than patients without AKI (724 of 5608 [12.9%] vs 288 of 3462 [8.3%]; P < .001). On multivariable analysis accounting for sCr stage, comorbidities, and illness severity, UO stages 2 and 3 were associated with a higher 90-day mortality (odds ratios, 2.4 [95% CI, 1.6-3.8; P < .001] and 6.2 [95% CI, 3.7-10.5; P < .001], respectively). These results remained significant in all sensitivity analyses.

Conclusions and Relevance

The findings of this cohort study suggest that oliguria lasting more than 12 hours (KDIGO stage 2 or 3) has major AKI diagnostic implications and is associated with outcomes irrespective of sCr elevations.

Epidemiology of Sepsis-Associated Acute Kidney Injury in Beijing, China: A Descriptive Analysis

Background

Sepsis is the most common contributing factor towards development of acute kidney injury (AKI), which is strongly associated to poor prognostic outcomes. There are numerous epidemiological studies about sepsis-associated acute kidney injury (S-AKI), however current literature is limited with the majority of studies being conducted only in the intensive care unit (ICU) setting. The aim of this study was to assess the epidemiology of S-AKI in all hospitalized in-patients.

Methods

This was a retrospective population-based study using a large regional population database in Beijing city from January, 2005 to December, 2017. It included patients with S-AKI. Patients with pre-existing end-stage kidney disease (ESKD), previous history of kidney transplantation, or being pregnant were excluded. Patients’ demographic characteristics, incidence, risk factors and outcomes of S-AKI were analyzed. The contrast between different time periods, different levels of hospitals, and types of the hospitals (traditional Chinese medicine hospitals (TCMHs) and western medicine hospitals (WMHs)) was also compared using Mann–Whitney U-test.

Results

A total of 19,579 patients were included. The overall incidence of S-AKI in all in-patients was 48.1%. The significant risk factors by multivariate analysis for AKI included: age, male, being treated in a level-II hospital, pre-existing hypertension, chronic kidney disease (CKD), cirrhosis, atrial fibrillation (AF), ischemic heart disease (IHD), being admitted from emergency room, ICU admission, shock, pneumonia, intra-abdominal infection, bloodstream infection, respiratory insufficiency, acute liver injury, disseminated intravascular coagulation (DIC) and metabolic encephalopathy. The overall mortality rate in this cohort was 55%. The multivariate analysis showed that the significant risk factors for mortality included: age, being treated in a level-II hospital and TCMHs, being admitted from emergency room, pre-existing comorbidities (CKD, malignancy, cirrhosis and AF), shock, pneumonia, intra-abdominal infection, bloodstream infection, central nervous system (CNS) infection and respiratory insufficiency.

Conclusion

AKI is a common complication in patients with sepsis, and its incidence increases over time, especially when ICU admission is required. Exploring interventional strategies to address modifiable risk factors will be important to reduce incidence and mortality of S-AKI.

Penicillin versus anti-staphylococcal beta-lactams for penicillin-susceptible Staphylococcus aureus blood stream infections: a retrospective cohort study

The objective of the study is to assess the efficacy and tolerability of penicillins compared to anti-staphylococcal beta-lactams for treatment of penicillin-susceptible Staphylococcus aureus bloodstream infections (PSSA BSI). A retrospective cohort study was conducted of 140 sequential PSSA BSI presenting to a local health district (90 cases included). Penicillin susceptibility was confirmed by disc diffusion, Vitek® and Nitrocefin beta-lactamase methods. Clinical information regarding comorbidities and infection complexity was recorded. Antibiotic choice, dosage and duration were reviewed. Outcomes were compared according to the definitive treatment with either penicillin or ASBLs. The primary outcome was 30-day mortality. Secondary outcomes included renal injury, microbiological relapse and treatment tolerability. Ninety patients met inclusion criteria and were included in subsequent analysis. Of PSSA BSI, 69% were community acquired. Eighty-two percent had complex PSSA infections. The average duration of bacteraemia was 2.8 days (SD = 1.8 days). Sixty-six patients received definitive penicillin treatment, with a mean of 3.5 days of empiric antibiotics prior to penicillin. Twenty-four patients received definitive ASBL treatment (11 cefazolin, 13 flucloxacillin). There was no difference in 30-day mortality between groups (p = 1). There was no difference in renal injury (p > 0.5), hospital length of stay (p = 0.59) or microbiological relapse within 1 year (p = 0.17). Penicillin treatment was well tolerated. Our data supports penicillin as a suitable and well-tolerated alternative to ASBL in managing complex PSSA BSI.

Predictors of Acute Kidney Injury and 28-Day Mortality in Carbapenem-Resistant Acinetobacter baumannii Complex Bacteremia

Colistin is an, antibiotic used to treat carbapenem-resistant Acinetobacter baumannii complex (CRABC) infection. However, colistin is well known for its nephrotoxicity. To accurately assess the effects of colistin on acute kidney injury (AKI) and 28-day mortality, we investigated the risk factors associated with AKI and mortality in patients with CRABC bacteremia who received or never received colistin. Patients with CRABC bacteremia aged ≥18 years were retrospectively identified for 3 years at five tertiary teaching hospitals. AKI was defined by using the Kidney Disease Improving Global Outcomes criteria. AKI developed in 103 (34.9%) of the 295 patients enrolled patients. AKI developed more frequently in patients who received colistin than in patients who did not (46.7% vs. 29.5%, p = 0.004). Multivariate analysis showed that intravenous colistin usage was an independent risk factor for AKI in these patients. Nonfatal disease, catheter-related bloodstream infection, and administration of colistin were protective factors for 28-day mortality. However, the sequential organ failure assessment score and AKI were associated with poor outcomes. In conclusion, colistin may be a double-edged sword; although it causes AKI, it also reduces 28-day mortality in patients with CRABC bacteremia. Therefore, colistin administration as an appropriate antibiotic may improve CRABC bacteremia prognosis, despite its nephrotoxicity.

Association between acute kidney injury and mortality after successful cardiopulmonary resuscitation: a retrospective observational study

BACKGROUND AND OBJECTIVES

Acute Kidney Injury (AKI) affect mortality and morbidity in critically ill patients. There have been few studies examining the prevalence of AKI and mortality after successful cardiopulmonary resuscitation. In the present study, we investigated the association between AKI and mortality in post-cardiac arrest patients admitted to the Intensive Care Unit (ICU).

METHODS

Our retrospective analysis included 109 patients, admitted to the ICU following successful cardiopulmonary resuscitation between 2014 and 2016. We compared two scoring systems to estimate mortality.

RESULTS AND DISCUSSION

AKI were diagnosed in 46.7% (n = 51) of the patients based on the RIFLE criteria and 66.1% (n = 72) using the KDIGO. Mortality rate was significantly higher among patients with AKI diagnosed according to the RIFLE criteria (p = 0.012) and those with AKI diagnosed using KDIGO criteria (p = 0.003). Receiver Operating Characteristic (ROC) analysis showed that both scoring systems were able to successfully detect mortality (Area under the ROC curve = 0.693 for RIFLE and 0.731 for KDIGO).

CONCLUSION

AKI increases mortality and morbidity rates after cardiac arrest. Although more renal injury and mortality were detected with KDIGO, the sensitivity and specificity of both scoring systems were similar in predicting mortality in patients with Return of Spontaneous Circulation (ROSC).

Hypothermia related to continuous renal replacement therapy: incidence and associated factors

OBJECTIVE

To evaluate the incidence of hypothermia in patients undergoing continuous renal replacement therapy in the intensive care unit. As secondary objectives, we determined associated factors and compared the occurrence of hypothermia between two modalities of continuous renal replacement therapy.

METHODS

A prospective cohort study was conducted with adult patients who were admitted to a clinical-surgical intensive care unit and underwent continuous renal replacement therapy in a high-complexity public university hospital in southern Brazil from April 2017 to July 2018. Hypothermia was defined as a body temperature ≤ 35ºC. The patients included in the study were followed for the first 48 hours of continuous renal replacement therapy. The researchers collected data from medical records and continuous renal replacement therapy records.

RESULTS

A total of 186 patients were equally distributed between two types of continuous renal replacement therapy: hemodialysis and hemodiafiltration. The incidence of hypothermia was 52.7% and was higher in patients admitted for shock (relative risk of 2.11; 95%CI 1.21 - 3.69; p = 0.009) and in those who underwent hemodiafiltration with heating in the return line (relative risk of 1.50; 95%CI 1.13 - 1.99; p = 0.005).

CONCLUSION

Hypothermia in critically ill patients with continuous renal replacement therapy is frequent, and the intensive care team should be attentive, especially when there are associated risk factors.

Polymyxin-induced nephrotoxicity and its predictors: a systematic review and meta-analysis of studies conducted using RIFLE criteria of acute kidney injury

Polymyxins are last-resort antibiotics re-emerged to treat infections caused by multidrug resistant (MDR) and extensively drug-resistant (XDR) Gram-negative bacterial infections. However, polymyxin-associated nephrotoxicity has become the main safety concern. Therefore, we conducted this systematic review and meta-analysis on polymyxin-induced nephrotoxicity and its predictors using studies conducted based on the validated RIFLE (Risk, Injury, Failure, Loss of Function and End-stage renal disease) criteria of acute kidney damage. Literature search was carried out through visiting legitimate databases and indexing services including PubMed, MEDLINE (Ovid®), EMBASE (Ovid®), and Scopus to retrieve relevant studies. Following screening and eligibility evaluation, relevant data were extracted from included studies and analyzed using STATA 15.0 and Rev-Man 5.3. Inverse variance method with random effects pooling model was used for the analysis of outcome measures at 95% confidence interval. Besides, meta-regression, meta-influence, and publication bias analyses were conducted. A total of 48 studies involving 6,199 adult patients aged ≥ 18 years were included for systematic review and meta-analysis. The pooled incidence of polymyxin-induced nephrotoxicity was found to be 45% (95% CI: 41- 49%; I² = 92.52%). Stratifying with RIFLE severity scales, pooled estimates of polymyxin-treated patients identified as 'risk', 'injury' and 'failure' were 17% (95% CI: 14-20%), 13% (95% CI: 11-15%), and 10% (95% CI: 9-11%), respectively. Besides, the pooled incidence of colistin-induced nephrotoxicity was about 48% (95% CI: 42-54%), whereas that of polymyxin B was 38% (95% CI: 32-44%). Likewise, colistin had 37% increased risk of developing nephrotoxicity compared to the polymyxin B treated cohorts (RR = 1.37, 95% CI: 1.13-1.67; I² = 57%). Older age (AOR = 1.03, 95% CI: 1.01-1.05), daily dose (AOR = 1.46, 95% CI: 1.09-1.96), underlying diabetes mellitus (AOR = 1.81, 95% CI: 1.25-2.63), and concomitant nephrotoxic drugs (AOR = 2.31, 95% CI: 1.79-3.00) were independent risk factors for polymyxin-induced nephrotoxicity. Patients with high serum albumin level were less likely (AOR = 0.69, 95% CI: 0.56-0.85] to experience nephrotoxicity compared to those with low albumin level. Despite the resurgence of these antibiotics for the chemotherapy of MDR/XDR-Gram-negative superbugs, the high incidence of nephrotoxicity has become a contemporary clinical concern. Being elderly, high daily dose, having underlying diseases such as diabetes, and use of concomitant nephrotoxic drugs were independent predictors of nephrotoxicity. Therefore, therapeutic drug monitoring should be done to these patients to outweigh the potential benefits of polymyxin therapy from its risk.

Utilization of Deep Learning for Subphenotype Identification in Sepsis-Associated Acute Kidney Injury

BACKGROUND AND OBJECTIVES

Sepsis-associated AKI is a heterogeneous clinical entity. We aimed to agnostically identify sepsis-associated AKI subphenotypes using deep learning on routinely collected data in electronic health records.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We used the Medical Information Mart for Intensive Care III database, which consists of electronic health record data from intensive care units in a tertiary care hospital in the United States. We included patients ≥18 years with sepsis who developed AKI within 48 hours of intensive care unit admission. We then used deep learning to utilize all available vital signs, laboratory measurements, and comorbidities to identify subphenotypes. Outcomes were mortality 28 days after AKI and dialysis requirement.

RESULTS

We identified 4001 patients with sepsis-associated AKI. We utilized 2546 combined features for K-means clustering, identifying three subphenotypes. Subphenotype 1 had 1443 patients, and subphenotype 2 had 1898 patients, whereas subphenotype 3 had 660 patients. Subphenotype 1 had the lowest proportion of liver disease and lowest Simplified Acute Physiology Score II scores compared with subphenotypes 2 and 3. The proportions of patients with CKD were similar between subphenotypes 1 and 3 (15%) but highest in subphenotype 2 (21%). Subphenotype 1 had lower median bilirubin levels, aspartate aminotransferase, and alanine aminotransferase compared with subphenotypes 2 and 3. Patients in subphenotype 1 also had lower median lactate, lactate dehydrogenase, and white blood cell count than patients in subphenotypes 2 and 3. Subphenotype 1 also had lower creatinine and BUN than subphenotypes 2 and 3. Dialysis requirement was lowest in subphenotype 1 (4% versus 7% [subphenotype 2] versus 26% [subphenotype 3]). The mortality 28 days after AKI was lowest in subphenotype 1 (23% versus 35% [subphenotype 2] versus 49% [subphenotype 3]). After adjustment, the adjusted odds ratio for mortality for subphenotype 3, with subphenotype 1 as a reference, was 1.9 (95% confidence interval, 1.5 to 2.4).

CONCLUSIONS

Utilizing routinely collected laboratory variables, vital signs, and comorbidities, we were able to identify three distinct subphenotypes of sepsis-associated AKI with differing outcomes.

Impact of the use of nephrotoxic drugs in critically ill pediatric patients

OBJECTIVE

To evaluate the association between the use of nephrotoxic drugs and acute kidney injury in critically ill pediatric patients.

METHODS

This was a retrospective cohort study involving all children admitted to the intensive care unit of a pediatric hospital during a 1-year period. Acute kidney injury was defined according to the KDIGO classification. Patients with a length of hospital stay longer than 48 hours and an age between 1 month and 14 years were included. Patients with acute or chronic nephropathy, uropathy, congenital or acquired heart disease, chronic use of nephrotoxic drugs, rhabdomyolysis and tumor lysis syndrome were excluded. Patients were classified according to the use of nephrotoxic drugs during their stay at the pediatric intensive care unit.

RESULTS

The sample consisted of 226 children, of whom 37.1% used nephrotoxic drugs, 42.4% developed acute kidney injury, and 7.5% died. The following drugs, when used alone, were associated with acute kidney injury: acyclovir (p < 0.001), vancomycin (p < 0.001), furosemide (p < 0.001) and ganciclovir (p = 0.008). The concomitant use of two or more nephrotoxic drugs was characterized as an independent marker of renal dysfunction (p < 0.001). After discharge from the pediatric intensive care unit, renal function monitoring in the ward was inadequate in 19.8% of cases.

CONCLUSION

It is necessary for intensivist physicians to have knowledge of the main nephrotoxic drugs to predict, reduce or avoid damage to their patients.

Ischemic Renal Injury: Can Renal Anatomy and Associated Vascular Congestion Explain Why the Medulla and Not the Cortex Is Where the Trouble Starts?

The kidneys receive approximately 20% of cardiac output and have a low fractional oxygen extraction. Quite paradoxically, however, the kidneys are highly susceptible to ischemic injury (injury associated with inadequate blood supply), which is most evident in the renal medulla. The predominant proposal to explain this susceptibility has been a mismatch between oxygen supply and metabolic demand. It has been proposed that unlike the well-perfused renal cortex, the renal medulla normally operates just above the threshold for hypoxia and that further reductions in renal perfusion cause hypoxic injury in this metabolically active region. An alternative proposal is that the true cause of ischemic injury is not a simple mismatch between medullary metabolic demand and oxygen supply, but rather the susceptibility of the outer medulla to vascular congestion. The capillary plexus of the renal outer medullary region is especially prone to vascular congestion during periods of ischemia. It is the failure to restore the circulation to the outer medulla that mediates complete and prolonged ischemia to much of this region, leading to injury and tubular cell death. We suggest that greater emphasis on developing clinically useful methods to help prevent or reverse the congestion of the renal medullary vasculature may provide a means to reduce the incidence and cost of acute kidney injury.

Vancomycin-Induced Kidney Injury: Animal Models of Toxicodynamics, Mechanisms of Injury, Human Translation, and Potential Strategies for Prevention

Vancomycin is a recommended therapy in multiple national guidelines. Despite the common use, there is a poor understanding of the mechanistic drivers and potential modifiers of vancomycin-mediated kidney injury. In this review, historic and contemporary rates of vancomycin-induced kidney injury (VIKI) are described, and toxicodynamic models and mechanisms of toxicity from preclinical studies are reviewed. Aside from known clinical covariates that worsen VIKI, preclinical models have demonstrated that various factors impact VIKI, including dose, route of administration, and thresholds for pharmacokinetic parameters. The degree of acute kidney injury (AKI) is greatest with the intravenous route and higher doses that produce larger maximal concentrations and areas under the concentration curve. Troughs (i.e., minimum concentrations) have less of an impact. Mechanistically, preclinical studies have identified that VIKI is a result of drug accumulation in proximal tubule cells, which triggers cellular oxidative stress and apoptosis. Yet, there are several gaps in the knowledge that may represent viable targets to make vancomycin therapy less toxic. Potential strategies include prolonging infusions and lowering maximal concentrations, administration of antioxidants, administering agents that decrease cellular accumulation, and reformulating vancomycin to alter the renal clearance mechanism. Based on preclinical models and mechanisms of toxicity, we propose potential strategies to lessen VIKI.

Evaluation of Renal Safety Between Imipenem/Relebactam and Colistin Plus Imipenem in Patients With Imipenem-Nonsusceptible Bacterial Infections in the Randomized, Phase 3 RESTORE-IMI 1 Study

Background

In the randomized controlled RESTORE-IMI 1 clinical trial (NCT02452047), imipenem/cilastatin (IMI) with relebactam (IMI/REL) was as effective as colistin plus IMI for the treatment of imipenem-nonsusceptible gram-negative infections. Differences in nephrotoxicity were observed between treatment arms. As there is no standard definition of nephrotoxicity used in clinical trials, we conducted analyses to further understand the renal safety profile of both treatments.

Methods

Nephrotoxicity was retrospectively evaluated using 2 acute kidney injury assessment criteria (Kidney Disease Improving Global Outcomes [KDIGO] and Risk, Injury, Failure, Loss, and End-stage Kidney Disease [RIFLE]). Additional outcomes included time to onset of protocol-defined nephrotoxicity and incidence of renal adverse events.

Results

Of 47 participants receiving treatment, 45 had sufficient data to assess nephrotoxicity (IMI/REL, n = 29; colistin plus IMI, n = 16). By KDIGO criteria, no participants in the IMI/REL but 31.3% in the colistin plus IMI group experienced stage 3 acute kidney injury. No IMI/REL-treated participants experienced renal failure by RIFLE criteria, vs 25.0% for colistin plus IMI. Overall, the time to onset of nephrotoxicity varied considerably (2–22 days). Fewer renal adverse events (12.9% vs 37.5%), including discontinuations due to drug-related renal adverse events (0% vs 12.5%), were observed in the IMI/REL group compared with the colistin plus IMI group, respectively.

Conclusions

Our analyses confirm the findings of a preplanned end point and provide further evidence that IMI/REL had a more favorable renal safety profile than colistin-based therapy in patients with serious, imipenem-nonsusceptible gram-negative bacterial infections.

ClinicalTrials.gov Identifier

NCT02452047.

Community prescribing of potentially nephrotoxic drugs and risk of acute kidney injury requiring renal replacement therapy in critically ill adults: A national cohort study

Background

Acute kidney injury demonstrates a high incidence in critically ill populations, with many requiring renal replacement therapy. Patients may be at increased risk of acute kidney injury if prescribed certain potentially nephrotoxic medications. We aimed to evaluate this association in ICU survivors.

Methods

Study design - secondary analysis of national cohort of ICU survivors to hospital discharge linked to Scottish healthcare datasets. Outcomes: primary - renal replacement therapy in ICU; secondary - early acute kidney injury (calculated using urine output and relative change from estimated baseline serum creatinine within first 24 h of ICU admission using modified-RIFLE criteria). Primary exposure: pre-admission community prescribing of at least one potential nephrotoxin: angiotensin-converting-enzyme inhibitors/angiotensin-receptor blockers, diuretics or nonsteroidal anti-inflammatory drugs. Statistical analyses: unadjusted associations - univariable logistic regression; confounder adjusted: multivariable logistic regression.

Results

During 2011-2013, 12,838 of 23,116 patients (55.5%) were prescribed at least one community prescription of at least one nephrotoxin; 1330 (5.8%) patients received renal replacement therapy; 3061 (15.7%) had acute kidney injury. Patients exposed to at least one examined nephrotoxin experienced higher incidence of renal replacement therapy (6.8% vs 4.5%; adjOR 1.46, 95%CI 1.24, 1.72, p < 0.001) and acute kidney injury (19.8% vs 10.9%; adjOR 1.61, 1.44, 1.80, p < 0.001). Increased risk of RRT was also found for angiotensin-converting-enzyme inhibitors/angiotensin-receptor blockers (adjOR 1.65, 1.40, 1.94), non-steroidal anti-inflammatory drugs (adjOR 1.12, 1.02, 1.44) and diuretics (adjOR 1.35, 1.14, 1.59).

Conclusions

Community prescribing of potential nephrotoxins increases the risk of renal replacement therapy/early acute kidney injury in ICU populations. Analyses were limited by the survivor dataset and potential residual confounding. Findings add consistency to previous research improving understanding of the harmful potential of these important medications and their timely cessation in acute illness.

The Incidence of Paediatric Acute Kidney Injury Identified Using an AKI E-Alert Algorithm in Six English Hospitals

Objective: Acute kidney injury (AKI) is a significant cause of morbidity and mortality among hospitalised patients. The objectives in this study were (i) to investigate the incidence of AKI using the National Health Services (NHS) AKI e-alert algorithm as a means of identifying AKI; and (ii) in a randomly selected sub-group of children with AKI identified using the algorithm, to evaluate the recognition and management of AKI. Patients and Methods: Retrospective cross-sectional study with initial electronic retrieval of creatinine measurements at six hospitals in England over a six-month period. Results were evaluated using the NHS AKI e-alert algorithm with recognition and management of AKI stages 1, 2 and 3 reviewed in a sub-set of randomly selected patient case notes. Patients aged 29 to 17 years were included. AKI stage 1 was defined as a rise of 1.5 - ≤2x baseline creatinine level; AKI stage 2 a rise of ≤ 2.0 and < 3.0; AKI stage 3 a rise of ≥ 3.0. Urine output was not considered for AKI staging. Results: 57,278 creatinine measurements were analysed. 5,325 (10.8%) AKI alerts were noted in 1,112 patients with AKI 1 (62%), AKI 2 (16%) and AKI 3 (22%). There were 222 (20%) <1y, 432 (39%) 1 ≤ 6y, 192 (17%) 6 ≤ 11y, 207 (19%) 11 ≤ 16y, and 59 (5%) 16-17y. Case notes of 123 of 1,112 [11.1%] children with AKI alerts were reviewed. Confirmed AKI was recognised with a documented management plan following its identification in n = 32 [26%] patients only. Conclusions: In this first multicentre study of the incidence of AKI in children admitted to selected hospitals across England, the incidence of AKI was 10.8% with most patients under the age of 6 years and with AKI stage 1. Recognition and management of AKI was seen in just over 25% children. These data highlight the need to improve recognition of AKI in hospitalised children in the UK.

Outcomes after intra-aortic balloon pump insertion in cardiac surgery patients

Objective

To assess whether preoperative versus intraoperative insertion of an intra-aortic balloon pump is associated with lower 30-day mortality or reduced length of hospital stay among patients who had an intra-aortic balloon pump inserted for cardiac surgery.

Methods

This was an observational study of patients who had an intra-aortic balloon pump inserted in the preoperative or intraoperative period of cardiac surgery in our department between 2000 and 2012. We assessed the association between preoperative versus intraoperative insertion of an intra-aortic balloon pump and 30-day mortality in a multivariable logistic regression analysis, including preoperative New York Heart Association class, postoperative atrial fibrillation, reoperation, postoperative creatinine and isolated coronary bypass grafting as cofactors. We used a multivariate linear model to assess whether a preoperative versus intraoperative intra-aortic balloon pump was associated with length of postoperative hospital stay, adjusting for reoperation, isolated coronary bypass grafting, heart valve surgery, sex, age, cardiopulmonary bypass time, aortic cross-clamp time, preoperative patients’ status (elective, urgency or emergency surgery) and preoperative myocardial infarction.

Results

Overall, 7,540 consecutive patients underwent open heart surgery in our department, and an intra-aortic balloon pump was inserted pre- or intraoperatively in 322 (4.2%) patients. The mean age was 67 ± 10.2 years old, the 30-day mortality was 12.7%, and the median length of hospital stay was 9 days (7 - 13). Preoperative versus intraoperative intra-aortic balloon pump insertion did not affect the incidence of 30-day mortality (adjusted OR = 0.69; 95% CI, 0.15 - 3.12; p = 0.63) and length of postoperative hospital stay (β = 5.3; 95%CI, -1.6 to 12.8; p = 0.13).

Conclusion

Preoperative insertion of an intra-aortic balloon pump was not associated with a lower 30-day mortality or reduced length of postoperative hospital stay compared to intraoperative insertion.

Is Computer-Assisted Aminoglycoside Dosing Managed by a Pharmacist a Safety Tool of Pharmacotherapy?

This pilot prospective study verified the hypothesis that use of computer-assisted therapeutic drug monitoring of aminoglycosides by pharmacists leads to better safety therapeutic outcomes and cost avoidance than only concentration measurement and dose adjustments based on a physician’s experience. Two groups of patients were enrolled according to the technique of monitoring. Patients (Group 1, n=52) underwent monitoring by a pharmacist using pharmacokinetic software. In a control group (Group 2, n=11), plasma levels were measured but not interpreted by the pharmacist, only by physicians. No statistically significant differences were found between the groups in factors influenced by therapy. However, the results are not statistically significant but a comparison of the groups showed a clear trend towards safety and cost avoidance, thus supporting therapeutic drug monitoring. Safety limits were achieved in 76 % and 63 % of cases in Groups 1 and 2, respectively. More patients achieved both concentrations (peak and trough) with falling eGFR in Group 1. In present pilot study, the pharmacist improved the care of patients on aminoglycoside therapy. A larger study is needed to demonstrate statistically significantly improved safety and cost avoidance of aminoglycoside therapy monitoring by the pharmacist using pharmacokinetic software.

Acute Tubular Injury is Associated With Severe Traumatic Brain Injury: in Vitro Study on Human Tubular Epithelial Cells

Acute kidney injury following traumatic brain injury is associated with poor outcome. We investigated in vitro the effects of plasma of brain injured patients with acute tubular kidney injury on kidney tubular epithelial cell function. we performed a prospective observational clinical study in ICU in a trauma centre of the University hospital in Italy including twenty-three ICU patients with traumatic brain injury consecutively enrolled. Demographic data were recorded on admission: age 39 ± 19, Glasgow Coma Score 5 (3–8). Neutrophil Gelatinase-Associated Lipocalin and inflammatory mediators were measured in plasma on admission and after 24, 48 and 72 hours; urine were collected for immunoelectrophoresis having healthy volunteers as controls. Human renal proximal tubular epithelial cells were stimulated with patients or controls plasma. Adhesion of freshly isolated human neutrophils and trans-epithelial electrical resistance were assessed; cell viability (XTT assay), apoptosis (TUNEL staining), Neutrophil Gelatinase-Associated Lipocalin and Megalin expression (quantitative real-time PCR) were measured. All patients with normal serum creatinine showed increased plasmatic Neutrophil Gelatinase-Associated Lipocalin and increased urinary Retinol Binding Protein and α1-microglobulin. Neutrophil Gelatinase-Associated Lipocalin was significantly correlated with both inflammatory mediators and markers of tubular damage. Patient’ plasma incubated with tubular cells significantly increased adhesion of neutrophils, reduced trans-epithelial electrical resistance, exerted a cytotoxic effect and triggered apoptosis and down-regulated the endocytic receptor Megalin compared to control. Plasma of brain injured patients with increased markers of subclinical acute kidney induced a pro-inflammatory phenotype, cellular dysfunction and apoptotic death in tubular epithelial cells.

The future for diagnostic tests of acute kidney injury in critical care: evidence synthesis, care pathway analysis and research prioritisation

BACKGROUND

Acute kidney injury (AKI) is highly prevalent in hospital inpatient populations, leading to significant mortality and morbidity, reduced quality of life and high short- and long-term health-care costs for the NHS. New diagnostic tests may offer an earlier diagnosis or improved care, but evidence of benefit to patients and of value to the NHS is required before national adoption.

OBJECTIVES

To evaluate the potential for AKI in vitro diagnostic tests to enhance the NHS care of patients admitted to the intensive care unit (ICU) and identify an efficient supporting research strategy.

DATA SOURCES

We searched ClinicalTrials.gov, The Cochrane Library databases, Embase, Health Management Information Consortium, International Clinical Trials Registry Platform, MEDLINE, metaRegister of Current Controlled Trials, PubMed and Web of Science databases from their inception dates until September 2014 (review 1), November 2015 (review 2) and July 2015 (economic model). Details of databases used for each review and coverage dates are listed in the main report.

REVIEW METHODS

The AKI-Diagnostics project included horizon scanning, systematic reviewing, meta-analysis of sensitivity and specificity, appraisal of analytical validity, care pathway analysis, model-based lifetime economic evaluation from a UK NHS perspective and value of information (VOI) analysis.

RESULTS

The horizon-scanning search identified 152 potential tests and biomarkers. Three tests, Nephrocheck^® (Astute Medical, Inc., San Diego, CA, USA), NGAL and cystatin C, were subjected to detailed review. The meta-analysis was limited by variable reporting standards, study quality and heterogeneity, but sensitivity was between 0.54 and 0.92 and specificity was between 0.49 and 0.95 depending on the test. A bespoke critical appraisal framework demonstrated that analytical validity was also poorly reported in many instances. In the economic model the incremental cost-effectiveness ratios ranged from £11,476 to £19,324 per quality-adjusted life-year (QALY), with a probability of cost-effectiveness between 48% and 54% when tests were compared with current standard care.

LIMITATIONS

The major limitation in the evidence on tests was the heterogeneity between studies in the definitions of AKI and the timing of testing.

CONCLUSIONS

Diagnostic tests for AKI in the ICU offer the potential to improve patient care and add value to the NHS, but cost-effectiveness remains highly uncertain. Further research should focus on the mechanisms by which a new test might change current care processes in the ICU and the subsequent cost and QALY implications. The VOI analysis suggested that further observational research to better define the prevalence of AKI developing in the ICU would be worthwhile. A formal randomised controlled trial of biomarker use linked to a standardised AKI care pathway is necessary to provide definitive evidence on whether or not adoption of tests by the NHS would be of value.

STUDY REGISTRATION

The systematic review within this study is registered as PROSPERO CRD42014013919.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Attempts to Limit Opioid Prescribing in Critically Ill Patients: Not So Easy, Not So Fast

OBJECTIVE

To discuss why opioids have been considered the long-standing first-line therapy for treating acute, severe nociceptive pain in critically ill patients and discuss considerations for limiting opioid overuse in the intensive care unit setting.

DATA SOURCES

Articles were identified through searches of PubMed and EMBASE from database inception until December 2018. Additional references were located through a review of the bibliographies of articles and clinical practice guidelines.

STUDY SELECTION AND DATA EXTRACTION

Original research articles excluding case reports were included if they concerned nonopioid agents for pain management in critically ill patients. The focus was on studies not included in the most recent pain management guidelines.

DATA SYNTHESIS

Ten studies were retrieved. Nonopioid therapies or opioid-sparing therapies have been touted as possible alternatives for critically ill patients, but they have particular adverse effects concerns in critically ill patients, often lack parenteral dosage forms, and frequently require dose adjustment or avoidance in patients with renal or hepatic dysfunction. Relevance to Patient Care and Clinical Practice: There is a well-recognized opioid epidemic that has been the subject of much discussion. Attempts to control the epidemic have focused on limiting opioid prescribing and using nonopioid alternatives, but there are special considerations when treating severe pain in critically ill patients that often preclude nonopioid analgesics.

CONCLUSIONS

There continues to be an unmet need for medications that are as effective as opioids for severe nociceptive pain in critically ill patients but without the adverse effect and abuse concerns. Until such medications are available, clinicians need to optimize prescribing of opioid and nonopioid analgesics.

Characteristics and associated factors of acute kidney injury among adult dengue patients: A retrospective single-center study

Severe dengue cases have been increasingly reported in Thailand, and the under-reporting of acute kidney injury (AKI) in cases of dengue viral infection has become an obstacle in obtaining an accurate description of the true nature and epidemiology of AKI. Because AKI may lead to patient morbidity and mortality, an early diagnosis is important in preventing its onset in dengue patients. This study aimed to determine the prevalence, clinical and laboratory characteristics, and associated factors of AKI among adult dengue patients. This retrospective study reviewed admission data from the medical records of adult dengue patients admitted to the Bangkok Hospital for Tropical Diseases between January 2012 and November 2017 and stratified these patients into AKI and non-AKI groups using the Kidney Disease Improving Global Outcomes criteria (KDIGO). A total of 1,484 patients were included in the study, with 71 categorized into the AKI group. The prevalence of AKI was 4.8%. In the AKI group, the predominant age range was 18–40 years (71.8%), with a female to male ratio of 1:2.7. These patients showed significantly (P < 0.05) higher proportions of altered consciousness, dyspnea, low mean arterial blood pressure, high-grade fever, major bleeding, severe thrombocytopenia, hypoalbuminemia, severe transaminitis, coagulopathy, metabolic acidosis, rhabdomyolysis, proteinuria, hematuria, and pyuria. Our study established that older age, male sex, diabetes mellitus, obesity, severe dengue, and coexisting bacterial infection were significant associated factors for AKI in dengue by multivariate analysis. A total of 10 (14.1%) patients with AKI received dialysis, among which 9 (12.7%) patients from the AKI group died. Our findings suggest that an awareness of AKI, its early diagnosis, and evaluation of clinical and laboratory characteristics of dengue patients will help clinicians to initiate appropriate therapy for dengue-associated AKI.

Stratification and Risk Reduction of Perioperative Acute Kidney Injury: An Update

Perioperative acute kidney injury is associated with morbidity and mortality. Several definitions have been proposed, incorporating small changes of serum creatinine and urinary output reduction as diagnostic criteria. In the surgical patient, comorbidities, type and timing of surgery, and nephrotoxins are important. Patient comorbidities remain a significant risk factor. Urgent or emergent surgery and cardiac or transplantation procedures are associated with a higher risk of acute kidney injury. Nephrotoxic drugs, contrast dye, and diuretics worsen preexisting kidney dysfunction or act as an adjunctive insult to perioperative injury. This review includes preoperative, intraoperative, and postoperative issues that can be mitigated.

Association between pediatric Risk, Injury, Failure, Loss and End Stage Renal Disease score and mortality in a pediatric intensive care unit: a retrospective study

OBJECTIVE

To evaluate the association between acute kidney injury through the pediatric Risk, Injury, Failure, Loss and End Stage Renal Disease score and mortality in a pediatric intensive care unit.

METHODS

This retrospective cohort study assessed all children admitted to the pediatric intensive care unit of a reference hospital in Brazil from January to December 2016. Patients were screened for the presence of acute kidney injury through the pediatric Risk, Injury, Failure, Loss and End Stage Renal Disease score. Patients were subdivided into the stages of Risk, Injury and Kidney Failure.

RESULTS

The sample comprised 192 children, of whom 45.8% developed acute kidney injury, with 79.5% of the cases identified up to 72 hours after admission. Patients with acute kidney injury showed a 3.74 increase risk of death (p = 0.01) than the control group. Patients with kidney failure had a mortality rate that was 8.56 times greater than that of the remaining sample (p < 0.001). The variables that were associated with the stages of acute kidney injury were nephrotoxic drugs (p = 0.025), renal replacement therapy (p < 0.001), vasoactive drugs (p < 0.001), pediatric risk of mortality 2 score (p = 0.023), fluid overload (p = 0.005), pediatric intensive care unit length of stay (p = 0.001) and death (p < 0.001).

CONCLUSION

In this study, the pediatric Risk, Injury, Failure, Loss and End Stage Renal Disease score proved to be a useful tool for the early identification of severely ill children with acute kidney injury, showing an association with mortality. We thus suggest its use for pediatric intensive care unit patient admission.

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.

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 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.

3-month prognostic impact of severe acute renal failure under veno-venous ECMO support: Importance of time of onset

PURPOSE

Veno-venous ECMO is increasingly used for the management of refractory ARDS. In this context, acute kidney injury (AKI) is a major and frequent complication, often associated with poor outcome. We aimed to identify characteristics associated with severe renal failure (Kidney Disease Improving Global Outcome (KDIGO) 3) and its impact on 3-month outcome.

METHODS

Between May 2009 and April 2016, 60 adult patients requiring VV-ECMO in our University Hospital were prospectively included.

RESULTS

AKI occurrence was frequent (75%; n=45), 51% of patients (n=31) developed KDIGO 3 - predominantly prior to ECMO insertion - and renal replacement therapy was required in 43% (n=26) of cases. KDIGO 3 was associated with a lower mechanical ventilation weaning rate (24% vs 68% for patients with no AKI or other stages of AKI; p<0.001) and a higher 90-day mortality rate (72% vs 32%, p=0.002). Multivariate logistic regression suggested that KDIGO 3 occurrence prior to ECMO insertion, as well as PaCO2>57mmHg and mSOFA>12 were independent risks factors for 90-day mortality.

CONCLUSION

KDIGO 3 AKI occurrence is correlated with the severity of patients' clinical condition prior to ECMO insertion and is negatively associated with 90-day survival.

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.

Early Renal Replacement Therapy Versus Standard Care in the ICU: A Systematic Review, Meta-Analysis, and Cost Analysis

OBJECTIVE:

Renal replacement therapy (RRT) is the treatment of choice for severe acute kidney injury, but there are no firm guidelines as to the time of initiation of RRT in the critically ill. The primary objective of this study is to determine 1-month mortality rates of early versus late dialysis in critical care. As secondary end points, we provide a cost analysis of early versus late RRT initiation, intensive care unit (ICU) length of stay (LOS), hospital LOS, and number of patients on dialysis at day 60 postrandomization.

DATA SOURCES:

We identified all randomized controlled trials (RCTs) through EMLINE and MEDBASE that examined adult patients admitted to critical care who were randomized to receiving early dialysis versus standard of care.

STUDY SELECTION:

Inclusion criteria: (1) RCTs conducted after the year 2000, (2) the population evaluated had to be adults admitted to ICU, (3) the intervention had to be early RRT versus standard care, and (4) outcomes had to measure patient mortality.

DATA EXTRACTION:

Two independent investigators reviewed search results and identified appropriate studies. Information was extracted using standardized case report forms.

DATA SYNTHESIS:

Overall, 7 RCTs were included with a total of 1400 patients. Early RRT showed no survival benefit when compared to standard treatment (odds ratio [OR], 0.90 95% confidence interval [95% CI] 0.70-1.15, P = .39). There was no significant difference in length of hospital stay in patients with early RRT (-1.55 days [95% CI -4.75 to 1.65, P = .34]), in length of ICU stay (-0.79 days [95% CI -2.09 to 0.52], P = .24), or proportion of patients on dialysis at day 60 (OR 0.93 [95% CI 0.62 to 1.43], P = .79). Per patient, there is likely a small increase in costs (<US$1000) owing to increased total dialysis.

CONCLUSION:

Across all measured domains, there is no clear benefit to early RRT. Moreover, this intervention may result in increased costs and exposes patients to an invasive therapy with potential harm.

Incidence, timing and outcome of AKI in critically ill patients varies with the definition used and the addition of urine output criteria

Background

Acute kidney injury (AKI) is a serious complication of critical illness with both attributed morbidity and mortality at short-term and long-term. The incidence of AKI reported in critically ill patients varies substantially with the population evaluated and the definitions used. We aimed to assess which of the AKI definitions (RIFLE, AKIN or KDIGO) with or without urine output criteria recognizes AKI most frequently and quickest. Additionally, we conducted a review on the comparison of incidence proportions of varying AKI definitions in populations of critically ill patients.

Methods

We included all patients with index admissions to our intensive care unit (ICU) from January 1^st, 2014 until June 11^th, 2014 to determine the incidence and onset of AKI by RIFLE, AKIN and KDIGO during the first 7 days of ICU admission. We conducted a sensitive search using PubMed evaluating the comparison of RIFLE, AKIN and KDIGO in critically ill patients

Results

AKI incidence proportions were 15, 21 and 20% respectively using serum creatinine criteria of RIFLE, AKIN and KDIGO. Adding urine output criteria increased AKI incidence proportions to 35, 38 and 38% using RIFLE, AKIN and KDIGO definitions. Urine output criteria detected AKI in patients without AKI at ICU admission in a median of 13 h (IQR 7–22 h; using RIFLE definition) after admission compared to a median of 24 h using serum creatinine criteria (IQR24-48 h). In the literature a large heterogeneity exists in patients included, AKI definition used, reference or baseline serum creatinine used, and whether urine output in the staging of AKI is used.

Conclusion

AKIN and KDIGO criteria detect more patients with AKI compared to RIFLE criteria. Addition of urine output criteria detect patients with AKI 11 h earlier than serum creatinine criteria and may double AKI incidences in critically ill patients. This could explain the large heterogeneity observed in literature.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0487-8) contains supplementary material, which is available to authorized users.

Prognostics factors for mortality and renal recovery in critically ill patients with acute kidney injury and renal replacement therapy

Objective

Identify prognostic factors related to mortality and non-recovery of renal function.

Methods

A prospective single-center study was conducted at the intensive care medicine department of a university hospital between 2012 and 2015. Patients with acute kidney injury receiving continuous renal replacement therapy were included in the study. Clinical and analytical parameters were collected, and the reasons for initiation and discontinuation of renal replacement therapy were examined.

Results

A total of 41 patients were included in the study, of whom 43.9% had sepsis. The median Simplified Acute Physiology Score II (SAPSII) was 56 and the mortality was 53.7%, with a predicted mortality of 59.8%. The etiology of acute kidney injury was often multifactorial (56.1%). Survivors had lower cumulative fluid balance (median = 3,600mL, interquartile range [IQR] = 1,175 - 8,025) than non-survivors (median = 12,000mL, IQR = 6,625 - 17,875; p = 0.004). Patients who recovered renal function (median = 51.0, IQR = 45.8 - 56.2) had lower SAPS II than those who do not recover renal function (median = 73, IQR = 54 - 85; p = 0.005) as well as lower fluid balance (median = 3,850, IQR = 1,425 - 8,025 versus median = 11,500, IQR = 6,625 - 16,275; p = 0.004).

Conclusions

SAPS II at admission and cumulative fluid balance during renal support therapy were risk factors for mortality and non-recovery of renal function among critically ill patients with acute kidney injury needing renal replacement therapy.

Drug-associated acute kidney injury: who's at risk?

The contribution of nephrotoxic medications to the development of acute kidney injury (AKI) is becoming better understood concomitant with the increased incidence of AKI in children. Treatment of AKI is not yet available, so prevention continues to be the most effective approach. There is an opportunity to mitigate severity and prevent the occurrence of AKI if children at increased risk are identified early and nephrotoxins are used judiciously. Early detection of AKI is limited by the dependence of nephrologists on serum creatinine as an indicator. Promising new biomarkers may offer early detection of AKI prior to the rise in serum creatinine. Early detection of evolving AKI is improving and offers opportunities for better management of nephrotoxins. However, the identification of patients at increased risk will remain an important first step, with a focus on the use of biomarker testing and interpretation of the results.

Acute kidney injury-incidence, prognostic factors, and outcome of patients in an Intensive Care Unit in a tertiary center: A prospective observational study

BACKGROUND AND AIMS

The information regarding the incidence of acute kidney injury (AKI) in medical Intensive Care Units (ICUs) in South India is limited. The aim of the study was to find the incidence, prognostic factors, and outcome of patients with AKI. We also assessed whether only urine output criteria of risk, injury, failure, loss, end (RIFLE) classification can be used to look at the outcome of AKI.

PATIENTS AND METHODS

This was a prospective, cross-sectional study of 6 months duration in a 28 bedded medical ICU of a tertiary center. AKI was defined as an absolute creatinine value of>1.6 mg/dl or a 25% increase from baseline creatinine values.

RESULTS

The incidence of AKI was 16.1%, and mortality was 7.8% in our study population. Among patients with AKI 87 (75.7%) patients had sepsis. 71.3% patients had metabolic acidosis on admission, and 47.8% patients were in shock. 57.4% of patient's required mechanical ventilation (MV). 39.1% of AKI patients required renal replacement therapy (RRT). Requirement of RRT was significantly affected by increasing age, Acute Physiology and Chronic Health Evaluation II and sequential organ failure assessment scores on admission, serum creatinine, and use of vasopressors. 49.5% of patients with AKI died within 28 days. Increasing age, MV, hemodialysis (HD), hypertension, chronic kidney disease, and requirement of noradrenaline support were associated with increasing 28 days mortality. The maximum RIFLE score with urine output criteria showed association to the requirement of HD in univariate analysis but did not show relation to mortality.

CONCLUSION

The incidence of AKI was 16.1% in critically ill patients. In patients with AKI, 39.1% patients required HD and 28 days mortality was 49.5%. The study also showed good univariate association of urine output criteria of RIFLE classification to the requirement of HD in AKI patients.

Incidence and mortality of postoperative acute kidney injury in non-dialysis patients: comparison between the AKIN and KDIGO criteria

OBJECTIVES

This retrospective study determines whether the kidney disease: improving global outcomes (KDIGO) criteria are superior to acute kidney injury network (AKIN) criteria in detecting non-dialysis AKI events and predicting mortality in chronic kidney disease (CKD) patients after surgery.

METHODS

Surgical patients who were admitted to the intensive care unit were enrolled. Non-dialysis AKI cases were defined using either KDIGO or AKIN creatinine criteria and stratified by CKD stages. The adjusted hazard ratios (AHRs) for in-hospital mortality are compared to those without AKI. The cumulative survival curves and the predictability for mortality are accessed by Kaplan-Meier method and calculating the area under the curve (AUC) for the receiver operating characteristic (ROC) curve, respectively.

RESULTS

From a total of 826 postoperative patients, the overall in-hospital mortality rate was 11.6% (96 cases) and that for AKI according to KDIGO and AKIN criteria was 30.0% (248 cases) and 31.0% (256 cases). The cumulative survival curve stratified by CKD and AKI stages were comparable between KDIGO and AKIN criteria. The discriminative power for mortality stratified by CKD stages for KDIGO and AKIN criteria are as followed: all subjects: 0.678 versus 0.670 (both ps <0.001); non-CKD: 0.800 versus 0.809 (both ps <0.001); early-stage CKD: 0.676 versus 0.676 (both ps <0.001); late-stage CKD: 0.674 versus 0.660 (ps were <0.001 and 0.003).

CONCLUSION

The KDIGO criteria are superior to AKIN criteria in predicting mortality after surgery, especially in those with advanced CKD.

A comparison of RIFLE, AKIN, KDIGO, and Cys-C criteria for the definition of acute kidney injury in critically ill patients

PURPOSE

AKI is a major clinical problem and predictor of prognosis in critically ill patients. The aim of our study was to determine whether the new Cys-C criteria for identification and prognosis of AKI were superior to the RIFLE, AKIN, and KDIGO criteria.

METHODS

In the retrospective and multicenter study, the incidence of AKI was identified by the four criteria. Receiver operating characteristic (ROC) curve was applied to compare the predictive ability for 28-day mortality, and logistic regression analysis was used for the calculation of odds ratios and 95 % confidence intervals.

RESULTS

In the 1036 patients enrolled, the incidences of AKI were 26.4, 34.1, 37.8, and 36.1 %, respectively, under the four criteria. Patients with AKI had higher mortality and longer length of stay than those without in all definitions. Concordance in AKI diagnosis between Cys-C and KDIGO criteria was 95.9 %, higher than AKIN and RIFLE criteria (p < 0.0001). The area under ROC curves was 0.7023 for Cys-C criteria, which was a significantly greater discrimination (p < 0.05).

CONCLUSION

KDIGO criteria identified significantly more AKI and AKI patients had significantly higher 28-day mortality than patients without AKI. The Cys-C criteria were more predictive for short-term outcomes than other three criteria among critically ill patients.

Impact of Acute Kidney Injury on Outcome in Patients With Severe Acute Respiratory Failure Receiving Extracorporeal Membrane Oxygenation

OBJECTIVES

Extracorporeal lung support is currently used in the treatment of patients with severe respiratory failure until organ recovery and as a bridge to further therapeutic modalities. The aim of our study was to evaluate the impact of acute kidney injury on outcome in patients with acute respiratory distress syndrome under venovenous extracorporeal membrane oxygenation support and to analyze the association between prognosis and the time of occurrence of acute kidney injury and renal replacement therapy initiation.

DESIGN

Retrospective observational study.

SETTING

A large European extracorporeal membrane oxygenation center, University Medical Center Regensburg, Germany.

PATIENTS

A total of 262 consecutive adult patients with acute respiratory distress syndrome have been treated with extracorporeal membrane oxygenation between January 2007 and May 2012.

INTERVENTIONS

None.

MEASUREMENT AND MAIN RESULTS

Patient median age was 49 years (range, 18-78 yr); 183 (69.8%) were male. The leading cause of lung failure was pneumonia. The median Sequential Organ Failure Assessment score was 12.0 (8.8-15.0), and the median lung injury score was 3.3 (3.3-3.7). The median extracorporeal membrane oxygenation support duration was 9 days (6-15 d). One hundred eighty-three patients (69.8%) were successfully weaned and 156 patients (59.9%) survived to hospital discharge. One hundred thirty-one patients (50.0%) were treated with renal replacement therapy during extracorporeal membrane oxygenation support. The survival rate was significantly lower in patients requiring renal replacement therapy compared with those without renal replacement therapy (47.3% vs 71.8%; p < 0.001) overall. The Kaplan-Meier survival curves differed significantly for patients without renal replacement therapy versus patients with renal replacement therapy prior to extracorporeal membrane oxygenation support (p = 0.003). Furthermore, the multivariate logistic regression analysis suggests that the necessity of renal replacement therapy prior to extracorporeal membrane oxygenation insertion was an independent risk factor for mortality (95% CI, 0.77-0.88; p < 0.001). However, the necessity of renal replacement therapy during extracorporeal membrane oxygenation support was not an independent risk factor for mortality in these patients (p = 0.37).

CONCLUSIONS

Acute kidney injury is a major complication in acute respiratory distress syndrome probably mirroring severe systemic disease. In our cohort, development of acute kidney injury requiring renal replacement therapy prior to extracorporeal membrane oxygenation insertion was negatively associated with survival, whereas acute kidney injury that developed during extracorporeal membrane oxygenation support was not.

Septic versus non-septic acute kidney injury in critically ill patients: characteristics and clinical outcomes

OBJECTIVE

This study aimed to describe and compare the characteristics and clinical outcomes of patients with septic and non-septic acute kidney injury.

METHODS

This study evaluated an open cohort of 117 critically ill patients with acute kidney injury who were consecutively admitted to an intensive care unit, excluding patients with a history of advanced-stage chronic kidney disease, kidney transplantation, hospitalization or death in a period shorter than 24 hours. The presence of sepsis and in-hospital death were the exposure and primary variables in this study, respectively. A confounding analysis was performed using logistic regression.

RESULTS

No significant differences were found between the mean ages of the groups with septic and non-septic acute kidney injury [65.30±21.27 years versus 66.35±12.82 years, respectively; p=0.75]. In the septic and non-septic acute kidney injury groups, a predominance of females (57.4% versus 52.4%, respectively; p=0.49) and Afro-descendants (81.5% versus 76.2%, respectively; p=0.49) was observed. Compared with the non-septic patients, the patients with sepsis had a higher mean Acute Physiology and Chronic Health Evaluation II score [21.73±7.26 versus 15.75±5.98; p<0.001)] and a higher mean water balance (p=0.001). Arterial hypertension (p=0.01) and heart failure (p<0.001) were more common in the non-septic patients. Septic acute kidney injury was associated with a greater number of patients who required dialysis (p=0.001) and a greater number of deaths (p<0.001); however, renal function recovery was more common in this group (p=0.01). Sepsis (OR: 3.88; 95%CI: 1.51-10.00) and an Acute Physiology and Chronic Health Evaluation II score >18.5 (OR: 9.77; 95%CI: 3.73-25.58) were associated with death in the multivariate analysis.

CONCLUSION

Sepsis was an independent predictor of death. Significant differences were found between the characteristics and clinical outcomes of patients with septic versus non-septic acute kidney injury.