Are There Modifiable Risk Factors to Improve AKI?

Influence of the type of anaesthesia on acute kidney injury after nephrectomy: a randomised controlled trial

INTRODUCTION

Acute kidney injury develops frequently after nephrectomy, causing increased hospital duration of stay and mortality. Both propofol and volatile anaesthetic agents are thought to have renoprotective effects. We investigated whether the type of maintenance anaesthetic (propofol or desflurane) affected the incidence of acute kidney injury after nephrectomy.

METHODS

This single-centre, randomised controlled trial enrolled adult patients with renal cell carcinoma undergoing nephrectomy. In patients allocated to the propofol group, anaesthesia was induced and maintained using a target-controlled infusion of propofol. In patients allocated to the desflurane group, anaesthesia was induced with a bolus of thiopental and maintained with desflurane. Both groups received a target-controlled infusion of remifentanil during surgery. The primary outcome was the incidence of acute kidney injury within 7 postoperative days based on the serum creatinine component of the Kidney Disease: Improving Global Outcomes criteria.

RESULTS

We analysed 317 patients (median (IQR [range]) age 62 (52-70 [26-85] y); 221 (70%) men). Postoperative AKI developed in 79 (25%) patients: 43 (27%) in the propofol group and 36 (23%) in the desflurane group (absolute risk difference (95%CI) 4.6 (-4.9-14.0%), p = 0.347). The severity of kidney injury was stage 1 in 76 patients, stage 2 in two patients and stage 3 in one patient.

DISCUSSION

The type of anaesthetic maintenance drug (propofol vs. desflurane) did not affect the incidence of acute kidney injury after nephrectomy. Future research might be better directed towards investigating other potentially modifiable risk factors for postoperative acute kidney injury in this patient population.

Association between intraoperative tidal volume and postoperative acute kidney injury in non-cardiac surgical patients using a propensity score-weighted analysis

Acute kidney injury (AKI) is related to adverse clinical outcomes. Therefore, identifying patients at increased risk of postoperative AKI and proactively providing appropriate care is crucial. However, only a limited number of modifiable risk factors have been recognized to mitigate AKI risk. We retrospectively analyzed adult patients who underwent endotracheal intubation and mechanical ventilation of more than 2 h during non-cardiac surgery at Seoul National University Hospital from January 2011 to November 2022. Patients were grouped into low- or high-tidal volume groups based on their intraoperative tidal volume relative to their predicted body weight (PBW) of 8 ml/kg. The association between intraoperative tidal volume and postoperative AKI was evaluated using inverse probability of treatment weighting (IPTW), adjusting for various preoperative confounders. Among the 37,726 patients included, the incidence of postoperative AKI was 4.1%. The odds of postoperative AKI risk were significantly higher in the high-tidal volume group than in the low-tidal volume group before and after IPTW (odds ratio [OR] 1.20, 95% confidence interval [CI] 1.08-1.32, P = 0.001 and OR: 1.10, 95% CI 1.02-1.19, P = 0.010, respectively). In the multivariable logistic regression analysis after IPTW, a high tidal volume was independently associated with an increased risk of postoperative AKI (OR: 1.21, 95% CI 1.12-1.30, P < 0.001). In this propensity score-weighted analysis, an intraoperative high tidal volume of more than 8 ml/kg PBW was significantly associated with an increased risk of postoperative AKI after IPTW in non-cardiac surgical patients. Intraoperative tidal volume showed potential as a modifiable risk factor for preventing postoperative AKI.

The association between albumin and mortality in patients with acute kidney injury: a retrospective observational study

BACKGROUND

While the association between decreased serum albumin (ALB) levels and increased risk of acute kidney injury (AKI) is well established, the risk of death among patients with AKI with low serum ALB levels is unclear. We aimed to evaluate the association between serum ALB levels in patients with AKI and mortality, and help guide their clinical management.

METHODS

The included patients were those diagnosed with AKI and admitted to Zhejiang Provincial People's Hospital between January 2018 and December 2020. The clinical endpoint was all-cause mortality rate at 90-days and 1-year. Patients were divided into four groups according to the quartiles (Qs) of ALB measurements at admission. Cumulative survival curves were calculated using Kaplan-Meier analysis, and Cox proportional risk models were used to assess the association between serum ALB levels and 90-day and 1-year all-cause mortality.

RESULTS

This study included 740 patients with AKI. Patients with measured ALB values were classified into quartiles: Q1 ≤ 26.0 g/L (n = 188); Q2 = 26.1-30.5 g/L (n = 186); Q3 = 30.6-34.7 g/L (n = 183); Q4 ≥ 34.8 g/L (n = 183). Univariate analysis using Cox regression showed that for every 10 g/L increase in ALB, the 90-day and 1-year mortality decreased by 29%. Among the four subgroups, patients with lower ALB levels had a higher risk of death. After adjusting for demographics, comorbid conditions, inflammatory index, and medicine, the lowest ALB quartile (ALB < 26 g/L) was associated with increased risk of 90-day mortality (hazard ratio [HR], 1.76; 95% confidence interval [CI], 1.30 to 2.38, P < 0.001) and 1-year all-cause mortality (HR, 1.79; 95% CI, 1.33 to 2.41, P < 0.001).

CONCLUSIONS

ALB levels in patients with AKI were significantly correlated with prognosis, and the higher the level, the better the prognosis. Compared to patients with ALB ≥ 34.8 g/L, patients with 26.1 g/L < ALB ≤ 30.5 g/L had an increased risk of 90-day and 1-year all-cause mortality of approximately 40%, and patients with ALB ≤ 26.0 g/L had an increased risk of 90-day and 1-year all-cause mortality of approximately 76% and 79%, respectively.

Machine learning-based prediction model of acute kidney injury in patients with acute respiratory distress syndrome

BACKGROUND

Acute kidney injury (AKI) can make cases of acute respiratory distress syndrome (ARDS) more complex, and the combination of the two can significantly worsen the prognosis. Our objective is to utilize machine learning (ML) techniques to construct models that can promptly identify the risk of AKI in ARDS patients.

METHOD

We obtained data regarding ARDS patients from the Medical Information Mart for Intensive Care III (MIMIC-III) and MIMIC-IV databases. Within the MIMIC-III dataset, we developed 11 ML prediction models. By evaluating various metrics, we visualized the importance of its features using Shapley additive explanations (SHAP). We then created a more concise model using fewer variables, and optimized it using hyperparameter optimization (HPO). The model was validated using the MIMIC-IV dataset.

RESULT

A total of 928 ARDS patients without AKI were included in the analysis from the MIMIC-III dataset, and among them, 179 (19.3%) developed AKI after admission to the intensive care unit (ICU). In the MIMIC-IV dataset, there were 653 ARDS patients included in the analysis, and among them, 237 (36.3%) developed AKI. A total of 43 features were used to build the model. Among all models, eXtreme gradient boosting (XGBoost) performed the best. We used the top 10 features to build a compact model with an area under the curve (AUC) of 0.850, which improved to an AUC of 0.865 after the HPO. In extra validation set, XGBoost_HPO achieved an AUC of 0.854. The accuracy, sensitivity, specificity, positive prediction value (PPV), negative prediction value (NPV), and F1 score of the XGBoost_HPO model on the test set are 0.865, 0.813, 0.877, 0.578, 0.957 and 0.675, respectively. On extra validation set, they are 0.724, 0.789, 0.688, 0.590, 0.851, and 0.675, respectively.

CONCLUSION

ML algorithms, especially XGBoost, are reliable for predicting AKI in ARDS patients. The compact model maintains excellent predictive ability, and the web-based calculator improves clinical convenience. This provides valuable guidance in identifying AKI in ARDS, leading to improved patient outcomes.

Erythrocyte parameters, anemia conditions, and sex differences are associated with the incidence of contrast-associated acute kidney injury after coronary angiography

Objective

Contrast-associated acute kidney injury (CA-AKI) is a critical complication when applying contrast medium, and the risk factors of CA-AKI have not been fully clarified. This study aimed to explore the relationships of CA-AKI with erythrocyte parameters, anemia conditions, and sex differences in patients after coronary angiography (CAG).

Methods

In this retrospective study, 4,269 patients who underwent CAG were enrolled. CA-AKI was defined as an increase in plasma creatinine of at least 0.5 mg/dl (44 μmol/L) or 25% within 72 h after exposure to the contrast medium. Three erythrocyte parameters, including hemoglobin, hematocrit, and red blood cell (RBC) count, were collected on admission. Logistic regression analyses were used to examine the associations of sex differences and erythrocyte parameters with CA-AKI in the overall population, restricted cubic splines to visualize these associations flexibly. Moreover, stratified and sensitivity analyses were conducted to assess the robustness of the findings.

Results

Overall, the mean (± standard deviations) age of patients was 67.05 ± 10.77 years, and 759 subjects (17.8%) developed CA-AKI. The results showed L-shaped relationships between erythrocyte parameters and CA-AKI incidence in each model (all P < 0.001). The incidence of CA-AKI was positively associated with the severity of anemia, while it showed no significant differences among the types of anemia. Moreover, female patients undergoing CAG had a higher risk of CA-AKI than male patients. Mediation analysis verified that erythrocyte parameters exerted an indirect effect on the sex differences of CA-AKI incidences.

Conclusion

In conclusion, females, perioperative anemia conditions, and lower erythrocyte parameters (hemoglobin, hematocrit, and RBC count) were verified as risk factors of CA-AKI in patients undergoing CAG. Furthermore, lower erythrocyte parameters among females exerted indirect effects on the sex differences in CA-AKI incidence.

Hospitalisation Due to Community-Acquired Acute Kidney Injury and the Role of Medications: A Retrospective Audit

The aim of this study is to assess the use of high-risk medications in patients with community-acquired acute kidney injury (CA-AKI) and the differences in the characteristics and outcomes of CA-AKI based on the use of these medications. This is a retrospective audit of adults (≥35 years) with CA-AKI admitted to a large tertiary care hospital over a two-year period. We investigated the prevalence of SADMANS (sulfonylureas; angiotensin converting enzyme inhibitors; diuretics; metformin; angiotensin receptor blockers; nonsteroidal anti-inflammatory drugs; and sodium glucose co-transporter 2 inhibitors) medications use in people with CA-AKI prior to hospitalisation. Outcomes including CA-AKI severity, kidney function recovery and in-hospital mortality were examined and stratified by use of SADMANS medications. The study included 329 patients, with a mean (SD) age of 75 (12) years and a 52% proportion of females, who were hospitalised with CA-AKI. Most patients (77.5%) were taking at least one regular SADMANS medication upon admission. Overall, 40% of patients (n = 132) and 41% of those on SADMANS (n = 104) had hypovolaemia or associated symptoms such as vomiting and diarrhoea during admission. Over two-thirds (68.1%) had mild AKI on admission and patients who were taking SADMANS medications were more likely to have mild AKI. Patients on SADMANS had more comorbidities and a higher medication burden, but there were no differences in AKI severity on admission or outcomes such as length of hospitalisation, ICU admission, need for dialysis, recovery rates and mortality between the two groups. However, the high prevalence of SADMANS medications use among patients with CA-AKI indicates a potential for preventability of CA-AKI-led hospitalisations. Future studies are needed to gain better insights into the role of withholding this group of medications, especially during an acute illness.

Acute Kidney Injury and Renal Replacement Therapy: A Review and Update for the Perioperative Physician

Post-operative acute kidney injury is a devastating complication with significant morbidity and mortality associated with it. The perioperative anesthesiologist is in a unique position to potentially mitigate the risk of postoperative AKI, however, understanding the pathophysiology, risk factors and preventative strategies is paramount. There are also certain clinical scenarios, where renal replacement therapy may be indicated intraoperatively including severe electrolyte abnormalities, metabolic acidosis and massive volume overload. A multidisciplinary approach including the nephrologist, critical care physician, surgeon and anesthesiologist is necessary to determine the optimal management of these critically ill patients.

[Risk factors for early acute kidney injury after cardiac arrest in children in the pediatric intensive care unit and a prognostic analysis]

OBJECTIVES

To investigate the risk factors for acute kidney injury (AKI) in children with cardiac arrest (CA) and the influencing factors for prognosis.

METHODS

A retrospective analysis was performed on the medical records of the children who developed CA in the pediatric intensive care unit (PICU) of Hunan Children's Hospital from June 2016 to June 2021. According to the presence or absence of AKI within 48 hours after return of spontaneous circulation (ROSC) for CA, the children were divided into two groups: AKI (n=50) and non-AKI (n=113). According to their prognosis on day 7 after ROSC, the AKI group was further divided into a survival group (n=21) and a death group (n=29). The multivariate logistic regression analysis was used to investigate the risk factors for early AKI in the children with CA and the influencing factors for prognosis.

RESULTS

The incidence rate of AKI after CA was 30.7% (50/163). The AKI group had a 7-day mortality rate of 58.0% (29/50) and a 28-day mortality rate of 78.0% (39/50), and the non-AKI group had a 7-day mortality rate of 31.9% (36/113) and a 28-day mortality rate of 58.4% (66/113). The multivariate logistic regression analysis showed that long duration of cardiopulmonary resuscitation (OR=1.164, 95%CI: 1.088-1.246, P<0.001), low baseline albumin (OR=0.879, 95%CI: 0.806-0.958, P=0.003), and adrenaline administration before CA (OR=2.791, 95%CI: 1.119-6.961, P=0.028) were closely associated with the development of AKI after CA, and that low baseline pediatric critical illness score (OR=0.761, 95%CI: 0.612-0.945, P=0.014), adrenaline administration before CA (OR=7.018, 95%CI: 1.196-41.188, P=0.031), and mechanical ventilation before CA (OR=7.875, 95%CI: 1.358-45.672, P=0.021) were closely associated with the death of the children with AKI after CA.

CONCLUSIONS

Albumin should be closely monitored for children with ROSC after CA, especially for those with long duration of cardiopulmonary resuscitation, low baseline pediatric critical illness score, adrenaline administration before CA, and mechanical ventilation before CA, and such children should be identified and intervened as early as possible to reduce the incidence of AKI and the mortality rate.

The effect of different consensus definitions on diagnosing acute kidney injury events and their association with in-hospital mortality

BACKGROUND

Due to the existence of different AKI definitions, analyzing AKI incidence and associated outcomes is challenging. We investigated the incidence of AKI events defined by 4 different definitions (standard AKIN and KDIGO, and modified AKIN-4 and KDIGO-4) and its association with in-hospital mortality.

METHODS

A total of 7242 adult Greek subjects were investigated. To find the association between AKI stages and in-hospital mortality, we considered both the number of AKI events and the most severe stage of AKI reached by each patient, adjusted for age, sex, and AKI staging, using multivariable logistic regression. To predict mortality in AKI patients, as defined by the four definitions, a classification task with two prediction models (random forest and logistic regression) was also conducted.

RESULTS

The incidence of AKI using the KDIGO-4 was 6.72% for stage 1a, 15.71% for stage 1b, 8.06% for stage2, and 2.97% for stage3; however, these percentages for AKIN-4 were 11%, 5.83%, 1.75%, and 0.33% for stage 1a, stage 1b, stage 2, and stage 3, respectively. Results showed KDIGO-4 is more sensitive in detecting AKI events. In-hospital mortality increased as the stage of AKI events increased for both KDIGO-4 and AKIN-4; however, KDIGO-4 (KDIGO) had a higher odds ratio at a higher stage of AKI compared to AKIN-4 (AKIN). Lastly, when using KDIGO, random forest and logistic regression models performed almost equally with a c-statistic of 0.825 and 0.854, respectively.

CONCLUSION

The present study confirms that within the KDIGO AKI stage 1, there are two sub-populations with different clinical outcomes (mortality).

Clinical Characteristics and Outcomes of Acute Kidney Injury in Hospitalized Patients with Coronavirus Disease 2019: Experience at a Major Tertiary Care Center in Pakistan

Limited data exist on acute kidney injury (AKI) in patients hospitalized with coronavirus disease 2019 (COVID-19), its risk factors, and the outcomes from lower and middle-income countries. We determined the epidemiology of AKI and its outcomes in a retrospective observational study at a tertiary care center in Karachi, Pakistan, from October to December 2020. Demographic data, presenting clinical symptoms, laboratory results, and patient outcomes were collected from the medical records. AKI was defined according to the Kidney Disease Improving Global Outcomes criteria. Of 301 COVID-19 patients, AKI developed in 188 (62.5%). The peak stages of AKI were Stage 1 in 57%, Stage 2 in 14.9%, and Stage 3 in 27.7%. Of these, 15 (8%) required kidney replacement therapy (KRT). Patients admitted to the intensive care unit (63.8% vs. 34.5%), and those needing vasopressors (31.9% vs. 5.3%) or mechanical ventilation (25% vs. 2.7%) had a higher risk of AKI. Independent predictors of AKI were elevated blood urea nitrogen and creatinine (Cr) at presentation, mechanical ventilation, and the use of anticoagulants. AKI, the presence of proteinuria, elevated serum Cr at presentation, use of vasopressors, and a need for KRT were significantly associated with in-hospital death, and the likelihood of mortality increased with advanced stages of AKI. Compared with other countries, AKI occurred more frequently among hospitalized patients with COVID-19 in this Pakistani cohort and was associated with 7.7-fold higher odds of in-hospital death. Patients with severe AKI had a greater likelihood of mortality than those in earlier stages or without AKI.

Machine learning for the prediction of acute kidney injury in critical care patients with acute cerebrovascular disease

Purpose

Acute kidney injury (AKI) is a common complication and associated with a poor clinical outcome. In this study, we developed and validated a model for predicting the risk of AKI through machine learning methods in critical care patients with acute cerebrovascular disease.

Methods

This study was a retrospective study based on two different cohorts. Five machine learning methods were used to develop AKI risk prediction models. We used six popular metrics (AUROC, F2-Score, accuracy, sensitivity, specificity and precision) to evaluate the performance of these models.

Results

We identified 2935 patients in the MIMIC-III database and 499 patients in our local database to develop and validate the AKI risk prediction model. The incidence of AKI in these two different cohorts was 18.3% and 61.7%, respectively. Analysis showed that several laboratory parameters (serum creatinine, hemoglobin, white blood cell count, bicarbonate, blood urea nitrogen, sodium, albumin, and platelet count), age, and length of hospital stay, were the top ten important factors associated with AKI. The analysis demonstrated that the XGBoost had higher AUROC (0.880, 95%CI: 0.831–0.929), indicating that the XGBoost model was better at predicting AKI risk in patients with acute cerebrovascular disease than other models.

Conclusions

This study developed machine learning methods to identify critically ill patients with acute cerebrovascular disease who are at a high risk of developing AKI. This result suggested that machine learning techniques had the potential to improve the prediction of AKI risk models in critical care.

Fasting during Ramadan and acute kidney injury (AKI): a retrospective, propensity matched cohort study

Background

During the month of Ramadan, Muslims abstain from daytime consumption of fluids and foods, although some high-risk individuals are exempt. Because fasting's effects on the risk of acute kidney injury (AKI) have not been established, this study assesses the relationship between fasting and risk of AKI and identifies patients at high risk.

Methods

A single-center, retrospective, propensity-score matched, cohort study was conducted with data collected from adult patients admitted to the emergency room during Ramadan and the following month over two consecutive years (2016 and 2017). AKI was diagnosed based on the 2012 definition from the Kidney Disease: Improving Global Outcomes clinical practice guideline. Multivariable logistic regression analyses were used to examine the correlation and measure the effect of fasting on the incidence of AKI, and assess the effect of different variables on the incidence of AKI between the matching cohorts.

Results

A total of 1199 patients were included; after matching, each cohort had 499 patients. In the fasting cohort, the incidence of AKI and the risk of developing AKI were significantly lower (adjusted odds ratio (AOR) 0.65;95% confidence interval (CI) 0.44–0.98). The most indicative risk factors for AKI were hypertension (AOR 2.17; 95% CI 1.48–3.18), history of AKI (AOR 5.05; 95% CI 3.46–7.39), and liver cirrhosis (AOR 3.01; 95% CI 1.04–8.70). Patients with these factors or most other comorbidities in the fasting cohort had a lower risk of AKI as compared with their nonfasting counterparts.

Conclusion

The data show a strong reduction in the risk of developing AKI as a benefit of fasting, particularly in patients with comorbid conditions. Therefore, most patients with comorbid conditions are not harmed from fasting during Ramadan. However, larger prospective studies are needed to investigate the benefit of fasting in reducing the risk of developing AKI.

Effects of hyperuricaemia, with the superposition of being overweight and hyperlipidaemia, on the incidence of acute kidney injury following cardiac surgery: a retrospective cohort study

OBJECTIVES

Acute kidney injury (AKI) is a common complication of cardiac surgery. This study aimed to explore the effects of hyperuricaemia, being overweight and hyperlipidaemia as risk factors for AKI in patients following cardiac surgery (cardiac surgery-associated acute kidney injury (CSA-AKI)).

DESIGN

Retrospective observational study.

SETTING

University teaching, grade-A tertiary hospital in Shanghai, China.

PARTICIPANTS

Patients who underwent cardiac surgery from July 2015 to December 2015 in Zhongshan Hospital, Fudan University.

MAIN OUTCOME MEASURES

We investigated the effect of hyperuricaemia, in combination with being overweight and hyperlipidaemia, on the risk of CSA-AKI.

RESULTS

A total of 1420 patients were enrolled. The AKI incidence in the highest uric acid group was 44.4%, while that in the lowest uric acid group was 28.5% (p<0.001). Patients in the higher uric acid quartiles were more likely to be overweight and hyperlipidaemic at the same time (p<0.001). Multivariate logistic regression analysis showed that hyperuricaemia was an independent risk factor for AKI (OR=1.237, 95% CI 1.095 to 1.885; p=0.009); being overweight or hyperlipidaemia alone was not an independent risk factor, but the combination of being overweight and hyperlipidaemia was (OR=1.544, 95% CI 1.059 to 2.252; p=0.024). In the final model, the OR value increased to 3.126 when hyperuricaemia was combined with being overweight and hyperlipidaemia, and the Hosmer-Lemeshow test showed that all three models fit well (p=0.433, 0.638 and 0.597, respectively).

CONCLUSIONS

The combination of being overweight and having hyperlipidaemia was an independent risk factor, but being overweight or having hyperlipidaemia alone was not. The combination of hyperuricaemia, being overweight and hyperlipidaemia further increased the risk of CSA-AKI.

Acute Kidney Injury in Cardiac Surgery Patients: Role of Glomerular Filtration Rate and Fat-Free Mass

Summary. Background.

eGFR (estimated glomerular filtration rate) formulas may be inaccurate in overweight cardiac surgery patients, overestimating the kidney reserve. The aim of this study was to modify the eGFR formulas and to determine whether the modified eGFR is a more accurate predictor of acute kidney injury (AKI).

Materials and methods

The patients were assigned into 4 BMI groups as follows: normal weight (18.5– 25 kg/m²), pre-obesity (25–30 kg/m²), class I obese (30–35 kg/m²), class II and III obese (≥35 kg/m²). Cockcroft– Gault (CG) eGFR formula was modified by using the fat-free mass (FFM) derived from bioelectrical impedance. ROC-AUC curves were analyzed to identify the accuracy of the eGFR formulas (CG, CG modified with FFM, Mayo Clinic Quadratic equation, CKD-EPI, MDRD) to predict the AKI in each group.

Results

Although all of the used equations showed similar predictive power in the normal weight and overweight category, Mayo formula had the highest AUC in predicting the occurrence of AKI (ROC-AUC 0.717 and 0.624, p<0.05). However, in the group of patients with class I obesity, only the CG formula modified with a fat-free mass appeared to be predictive of postoperative AKI (ROC-AUC 0.631 p<0.05). None of the equations were accurate in the group of BMI (>35 kg/m²).

Conclusions

eGFR is a poor predictor of AKI, especially in the obese patients undergoing cardiac surgery. The only equation with a moderate predictive power for the class I obese patients was the CG formula modified with the fat-free mass.

Risk factors for kidney disorders in patients with type 2 diabetes at high cardiovascular risk: An exploratory analysis (DEVOTE 12)

AIM

To investigate risk factors associated with kidney disorders in patients with type 2 diabetes (T2D) at high cardiovascular (CV) risk.

METHODS

In DEVOTE, a cardiovascular outcomes trial, 7637 patients were randomised to insulin degludec (degludec) or insulin glargine 100 units/mL (glargine U100), with standard of care. In these exploratory post hoc analyses, serious adverse event reports were searched using Standardised MedDRA^® Queries related to chronic kidney disease (CKD) or acute kidney injury (AKI). Baseline predictors of CKD, AKI and change in estimated glomerular filtration rate (eGFR) were identified using stepwise selection and Cox or linear regression.

RESULTS

Over 2 years, eGFR (mL/min/1.73 m²) decline was small and similar between treatments (degludec: 2.70; glargine U100: 2.92). Overall, 97 and 208 patients experienced CKD and AKI events, respectively. A history of heart failure was a risk factor for CKD (hazard ratio [HR] 1.97 [95% confidence interval [CI] 1.41; 2.75]) and AKI (HR 2.28 [95% CI 1.64; 3.17]). A history of hepatic impairment was a significant predictor of CKD (HR 3.28 [95% CI 2.12; 5.07]) and change in eGFR (estimate: -8.59 [95% CI -10.20; -7.00]).

CONCLUSION

Our findings indicate that traditional, non-modifiable risk factors for kidney disorders apply to insulin-treated patients with T2D at high CV risk.

TRIAL REGISTRATION

NCT01959529 (ClinicalTrials.gov).

Acute Kidney Injury: From Diagnosis to Prevention and Treatment Strategies

Acute kidney injury (AKI) is characterized by an acute decrease in renal function that can be multifactorial in its origin and is associated with complex pathophysiological mechanisms. In the short term, AKI is associated with an increased length of hospital stay, health care costs, and in-hospital mortality, and its impact extends into the long term, with AKI being associated with increased risks of cardiovascular events, progression to chronic kidney disease (CKD), and long-term mortality. Given the impact of the prognosis of AKI, it is important to recognize at-risk patients and improve preventive, diagnostic, and therapy strategies. The authors provide a comprehensive review on available diagnostic, preventive, and treatment strategies for AKI.

Artificial Intelligence in Acute Kidney Injury Risk Prediction

Acute kidney injury (AKI) is a frequent complication in hospitalized patients, which is associated with worse short and long-term outcomes. It is crucial to develop methods to identify patients at risk for AKI and to diagnose subclinical AKI in order to improve patient outcomes. The advances in clinical informatics and the increasing availability of electronic medical records have allowed for the development of artificial intelligence predictive models of risk estimation in AKI. In this review, we discussed the progress of AKI risk prediction from risk scores to electronic alerts to machine learning methods.

The influence of prolonged temperature management on acute kidney injury after out-of-hospital cardiac arrest: A post hoc analysis of the TTH48 trial

BACKGROUND

Acute kidney injury (AKI) is common after cardiac arrest and targeted temperature management (TTM). The impact of different lengths of cooling on the development of AKI has not been well studied. In this study of patients included in a randomised controlled trial of TTM at 33 °C for 24 versus 48 h after cardiac arrest (TTH48 trial), we examined the influence of prolonged TTM on AKI and the incidence and factors associated with the development of AKI. We also examined the impact of AKI on survival.

METHODS

This study was a sub-study of the TTH48 trial, which included patients cooled to 33 ± 1 °C after out-of-hospital cardiac arrest for 24 versus 48 h. AKI was classified according to the KDIGO AKI criteria based on serum creatinine and urine output collected until ICU discharge for a maximum of seven days. Survival was followed for up to six months. The association of admission factors on AKI was analysed with multivariate analysis and the association of AKI on mortality was analysed with Cox regression using the time to AKI as a time-dependent covariate.

RESULTS

Of the 349 patients included in the study, 159 (45.5%) developed AKI. There was no significant difference in the incidence, severity or time to AKI between the 24- and 48-h groups. Serum creatinine values had significantly different trajectories for the two groups with a sharp rise occurring during rewarming. Age, time to return of spontaneous circulation, serum creatinine at admission and body mass index were independent predictors of AKI. Patients with AKI had a higher mortality than patients without AKI (hospital mortality 36.5% vs 12.5%, p < 0.001), but only AKI stages 2 and 3 were independently associated with mortality.

CONCLUSIONS

We did not find any association between prolonged TTM at 33 °C and the risk of AKI during the first seven days in the ICU. AKI is prevalent after cardiac arrest and TTM and occurs in almost half of all ICU admitted patients and more commonly in the elderly, with an increasing BMI and longer arrest duration. AKI after cardiac arrest is an independent predictor of time to death.

Protective effects of D-005, a lipid extract from Acrocomia crispa fruits, against ischemia/reperfusion-induced acute kidney injury in rats

Background

Acute kidney injury (AKI) induced by renal ischemia/reperfusion (IR) is associated with enhanced production of reactive oxygen species in renal tissues. D-005, a lipid extract obtained from Acrocomia crispa fruit, has previously shown antioxidant effects. The aim of this work was to evaluate the effects of D-005 on renal IR-induced AKI in rats.

Methods

Rats were randomized into seven groups including a negative control group (vehicle) without AKI and six groups with renal IR-induced AKI as follows: a positive control (vehicle); D-005 treatment at 25, 100, 200, or 400 mg/kg; and dexamethasone at 3 mg/kg. All treatments were orally administered as single doses 1 hour before AKI induction. Biomarkers (serum creatinine, urea, and uric acid concentrations), oxidative variables, and histopathological AKI changes were evaluated in blood and kidney tissues.

Results

All D-005 doses protected against IR-induced AKI in rats by significantly decreasing biomarkers and histopathological AKI changes as assessed by reduced serum concentrations of creatinine, urea, and uric acid. In addition, all D-005 doses decreased tubular damage, as shown by fewer detached cells and casts in the tubular lumen. D-005 reversed oxidation disturbance markers by decreasing malondialdehyde and sulfhydryl group concentrations in plasma and in kidney homogenates and by increasing kidney catalase activity. Dexamethasone, the reference substance, protected against IR-induced AKI in rats by reducing biochemical and histological variables of renal damage in a similar manner.

Conclusion

Administration of single oral doses of D-005 markedly and significantly protected against renal IR-induced AKI, possibly due to its known antioxidant effects.

Aspiration in the Fiberoptic Endoscopic Evaluation of Swallowing Associated with an Increased Risk of Mortality in a Cohort of Patients Suspected of Oropharyngeal Dysphagia

There is a general lack of published studies on the risk of mortality due to alterations in the safety of swallowing detected during the fiberoptic endoscopic evaluation of swallowing (FEES). We aimed at assessing the risk of mortality of the detection of aspiration, penetration, and pharyngeal residues by FEES. A cohort of consecutively evaluated patients suspected of experiencing oropharyngeal dysphagia undergoing FEES at a tertiary care university hospital were prospectively followed up on to assess mortality. The FEES findings, comorbidities, and potential confounders were studied as predictors of death using a Cox multivariate regression analysis. A total of 148 patients were included, 85 of whom were male (57.4%). The mean age (± standard deviation) was 52.7 years (± 22.1). The median of the follow-up time was 4.5 years. The most frequent conditions were stroke in 50 patients (33.8%), brain and spine traumas in 27 (18.2%), and neurodegenerative diseases in 19 (12.8%). Variables associated with mortality in bivariate analyses were age > 65 years (p < 0.001), pneumonia (p = 0.046), aspiration of any consistency (p < 0.001), and pharyngeal residues (p = 0.017). Variables independently associated with mortality in the Cox multivariate model were age (> 65 years) [adjusted hazard ratio (HR) 5.76; 95% CI 2.72 to 17.19; p = 0.001] and aspiration (adjusted HR: 3.96; 95% CI 1.82 to 14.64; p = 0.003). Aspiration detected by FEES and an age > 65 years are independent predictors of mortality in patients with oropharyngeal dysphagia.

Acute Kidney Injury in the Age of Enhanced Recovery Protocols

BACKGROUND

Acute kidney injury is a prevalent complication after abdominal surgery. With increasing adoption of enhanced recovery protocols, concern exists for concomitant increase in acute kidney injury.

OBJECTIVE

This study evaluated effects of enhanced recovery on acute kidney injury through identification of risk factors.

DESIGN

This was a retrospective cohort study comparing acute kidney injury rates before and after implementation of enhanced recovery protocol.

SETTINGS

The study was conducted at a large academic medical center.

PATIENTS

All of the patients undergoing elective colorectal surgery between 2010 and 2016, excluding patients with stage 5 chronic kidney disease, were included.

MAIN OUTCOME MEASURES

Patients before and after enhanced recovery implementation were compared, with rate of acute kidney injury as the primary outcome. Acute kidney injury was defined as a rise in serum creatinine ≥1.5 times baseline within 30 days of surgery. Multivariable logistic regression identified risk factors for acute kidney injury.

RESULTS

A total of 900 cases were identified, including 461 before and 439 after enhanced recovery; 114 cases were complicated by acute kidney injury, including 11.93% of patients before and 13.44% after implementation of enhanced recovery (p = 0.50). Five patients required hemodialysis, with 2 cases after protocol implementation. Multivariable logistic regression identified hypertension, functional status, ureteral stents, nonsteroidal anti-inflammatory drugs, operative time >200 minutes, and increased intravenous fluid administration on postoperative day 1 as predictors of acute kidney injury. Laparoscopic surgery decreased the risk of acute kidney injury. The enhanced recovery protocol was not independently associated with acute kidney injury.

LIMITATIONS

The study was limited by its retrospective and nonrandomized before-and-after design.

CONCLUSIONS

No difference in rates of acute kidney injury was detected before and after implementation of a colorectal enhanced recovery protocol. Independent predictors of acute kidney injury were identified and could be used to alter the protocol in high-risk patients. Future study is needed to determine whether protocol modifications will further decrease rates of acute kidney injury in this population. See Video Abstract at http://links.lww.com/DCR/A568.

U-shape association of serum albumin level and acute kidney injury risk in hospitalized patients

Background

While an association between hypoalbuminemia and increased risk of acute kidney injury (AKI) is well-established, the risk of AKI development and its severity among patients with elevated serum albumin is unclear. The aim of this study was to evaluate the risk of AKI in hospitalized patients stratified by various admission serum albumin levels.

Methods

This single-center retrospective study was conducted at a tertiary referral hospital. All adult hospitalized patients who had admission albumin levels available between January 2009 and December 2013 were enrolled. Admission albumin was categorized based on its distribution into six groups (≤2.4, 2.5–2.9, 3.0–3.4, 3.5–3.9, 4.0–4.4, and ≥4.5 mg/dL). The primary outcome was the incidence of hospital-acquired AKI (HAKI). Logistic regression analysis was performed to obtain the odds ratio of AKI for various admission albumin strata using the albumin 3.5 to 3.9 mg/dL (lowest incidence of AKI) as the reference group.

Results

Of the total 9,552 studied patients, HAKI occurred in 1,556 (16.3%) patients. The incidence of HAKI among patients with admission albumin ≤2.4, 2.5–2.9, 3.0–3.4, 3.5–3.9, 4.0–4.4, and ≥4.5 mg/dL was 18.3%, 14.3%, 15.5%, 14.2%, 16.7%, and 26.0%, respectively. After adjusting for potential confounders, admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk of HAKI with odds ratios of 1.52 (95% CI 1.18–1.94) and 2.16 (95% CI 1.74–2.69), respectively. While stage 1 HAKI was significantly more frequent among patients with admission albumin ≥4.5 mg/dL (23.0% vs. 11.6%, P<0.001), incidence of stage 3 HAKI was higher in those with albumin ≤2.4 mg/dL (2.8% vs 0.3%, P<0.001).

Conclusion

Admission serum albumin levels ≤2.4 and ≥4.5 mg/dL were associated with an increased risk for HAKI. Patients with admission albumin ≥4.5 mg/dL had HAKI with a lower intensity when compared with those who had admission albumin levels ≤2.4 mg/dL.

Clinical Profile and Outcome of Patients with Acute Kidney Injury Requiring Hemodialysis: Two Years' Experience at a Tertiary Hospital in Rwanda

Introduction

Acute kidney injury (AKI) requiring renal replacement therapy is associated with high mortality. The study assessed the impact of the introduction of hemodialysis (HD) on outcomes of patients with AKI in Rwanda.

Methods

A single center retrospective study that evaluated the clinical profile and survival outcomes of patients with AKI requiring HD [AKI-D] at a tertiary hospital in Rwanda. Data was collected on patients who received HD for AKI from September 2014 to December 2016. Patient demographics, comorbidities, clinical presentation, laboratory tests, and mortality were reviewed and analyzed. Predictors of mortality were assessed using age and gender adjusted multivariate analyses.

Results

Of the 82 eligible patients, median age was 38 years (IQR 28–57 years). Males comprised 51% of the cohort. Infectious diseases including malaria, pneumonia, and sepsis (35.1%) and pregnancy-related conditions (26.9%) were the most frequent comorbidities. Pulmonary oedema (54.9%) and uremic encephalopathy (50%) were top indications for HD. Mortality was 34.1%. On multivariate analysis, receipt of <5 sessions of HD (OR = 4.01, 95% CI 1.185–13.61, P = 0.026) and hyperkalemia (OR = 3.23, 95% CI 1.040–10.065, P = 0.043) were associated with mortality.

Conclusion

The availability of acute hemodialysis in Rwanda has resulted in improved patient survival and persistent hyperkalemia predicted higher mortality.