Diagnosis, evaluation, and management of acute kidney injury: a KDIGO summary (Part 1)

Iron metabolism indexes as predictors of the incidence of cardiac surgery-associated acute kidney surgery

BACKGROUND

Acute kidney injury (AKI) is a major complication following cardiac surgery. We explored the clinical utility of iron metabolism indexes for identification of patients at risk for AKI after cardiac surgery.

METHODS

This prospective observational study included patients who underwent cardiac surgery between March 2023 and June 2023. Iron metabolism indexes were measured upon admission to the intensive care unit. Multivariable logistic regression analyses were performed to explore the relationship between iron metabolism indexes and cardiac surgery-associated AKI (CSA-AKI). Receiver operating characteristic (ROC) curve was used to assess the predictive ability of iron, APACHE II score and the combination of the two indicators. Restricted cubic splines (RCS) was used to further confirm the linear relationship between iron and CSA-AKI.

RESULTS

Among the 112 recruited patients, 38 (33.9%) were diagnosed with AKI. Multivariable logistic regression analysis indicated that APACHE II score (odds ratio [OR], 1.208; 95% confidence interval [CI], 1.003-1.455, P = 0.036) and iron (OR 1.069; 95% CI 1.009-1.133, P = 0.036) could be used as independent risk factors to predict CSA-AKI. ROC curve analysis showed that iron (area under curve [AUC] = 0.669, 95% CI 0.572-0.757), APACHE II score (AUC = 0.655, 95% CI 0.557-0.744) and iron and APACHE II score combination (AUC = 0.726, 95% CI 0.632-0.807) were predictive indicators for CSA-AKI. RCS further confirmed the linear relationship between iron and CSA-AKI.

CONCLUSIONS

Elevated iron levels were independently associated with higher risk of CSA-AKI, and there was a linear relationship between iron and CSA-AKI.

Biomarkers in acute kidney injury

Acute kidney injury (AKI) is a multifactorial syndrome with a high risk of short- and long-term complications as well as increased health care costs. The traditional biomarkers of AKI, serum creatinine and urine output, have important limitations. The discovery of new functional and damage/stress biomarkers has enabled a more precise delineation of the aetiology, pathophysiology, site, mechanisms, and severity of injury. This has allowed earlier diagnosis, better prognostication, and the identification of AKI sub-phenotypes. In this review, we summarize the roles and challenges of these new biomarkers in clinical practice and research.

Association between serum osmolality and deteriorating renal function in patients with acute myocardial infarction: analysis of the MIMIC- IV database

BACKGROUND

To investigate the association between serum osmolality and deteriorating renal function in patients with acute myocardial infarction (AMI).

METHODS

Three thousand eight hundred eighty-five AMI patients from the Medical Information Mart for Intensive Care IV were enrolled for this study. The primary outcome was deteriorating renal function. Secondary outcomes included the new-onset of acute kidney injury (AKI) and progress of AKI. < 293.2725 mmol/L was defined as low serum osmolality, and ≥ 293.2725 mmol/L as high serum osmolality based on upper quartile. Univariate and multivariate logistic regression models were used to explore the associations between serum osmolality and the development of deteriorating renal function, the new-onset of AKI and progress of AKI among AMI patients. Subgroup analysis was also conducted.

RESULTS

One thousand three hundred ninety-three AMI patients developed deteriorating renal function. After adjusting all confounding factors, high serum osmolality was associated with increased risk of deteriorating renal function [odds ratio (OR) = 1.47, 95% confidence interval (CI): 1.22-1.78], new-onset of AKI (OR = 1.31, 95% CI: 1.01-1.69), and progress of AKI risk (OR = 1.26, 95% CI: 1.01-1.59) among AMI patients. In addition, when the stratified analysis was performed for age, AMI type, cardiogenic shock, and estimated glomerular filtration rate (eGFR), high serum osmolality was risk factor for the risk of deteriorating renal function among patients aged 65 years or older, without cardiogenic shock, and with an eGFR ≥ 60 mL/min/1.73m2.

CONCLUSION

Higher serum osmolality increased the risk of deteriorating renal function among AMI patients.

The value of lymphocyte-to-C-reactive protein ratio for predicting clinical outcomes in patients with sepsis in intensive care unit: a retrospective single-center study

Background

The lymphocyte-to-C-reactive protein ratio (LCR) was a novel biomarker of inflammation that had been implicated in various diseases. Nevertheless, the role of LCR in the context of sepsis patients admitted to the Intensive Care Unit (ICU) had not been thoroughly elucidated. This study aimed to determine the significance of the LCR in predicting the prognosis of sepsis patients within ICU.

Methods

A sample of sepsis patients requiring ICU care was selected from the Affiliated Hospital of Jiangsu University. These patients were then segmented into four quartiles based on their LCR levels. The primary endpoint of the study was 30-day mortality and the secondary endpoint was the occurrence of Acute Kidney Injury (AKI). Survival analysis, via the Kaplan-Meier method and log-rank test, was conducted to assess survival rates. Cox proportional hazards regression and logistic regression models were employed to investigate the association between LCR and clinical outcomes. Additional subgroup analyses were conducted to evaluate the influence of other confounding factors on the relationship between LCR and patient outcomes.

Results

A total of 1,123 patients were enrolled in this study, with a median age of 75 (65-84) years, and 707 (63.0%) of them were male. The 30-day mortality rate was 28.1%, while the incidence of AKI was 45.6%. A progressive decrease in LCR levels was found to be associated with an increased cumulative incidence of 30-day mortality (log-rank P < 0.001). Multivariable Cox proportional hazards analyses demonstrated that LCR was an independent predictor of 30-day mortality [per 1-unit increase in LCR: HR (95%CI): 0.370 (0.142-0.963); P = 0.042]. Additionally, multivariable logistic regression analysis revealed a significant association between LCR and AKI occurrence [per 1-unit increase in LCR: OR (95%CI): 0.541 (0.307-0.953); P = 0.034]. Furthermore, subgroup analysis indicated a stronger correlation for patients aged over 65 years compared to those aged 65 or younger (p for interaction <0.05) in predicting 30-day mortality or AKI occurrence based on LCR.

Conclusion

A reduction in LCR was notably linked to 30-day mortality and the occurrence of AKI in sepsis patients. These findings suggested that LCR could potentially serve as a valuable tool in identifying sepsis patients at a heightened risk of adverse outcomes.

Acute kidney injury in the acute care surgery patient: What you need to know

ABSTRACT

Acute kidney injury is associated with poor outcomes in the trauma and emergency general surgery population, and recent consensus definitions have allowed for significant advances in defining the burden of disease. The current definitions rely on overall functional measures (i.e., serum creatinine and urine output), which can be confounded by a variety of clinical factors. Biomarkers are increasingly being investigated as more direct diagnostic assays for the diagnosis of acute kidney injury and may allow earlier detection and more timely therapeutic intervention. Etiologies fall into two general categories: disorders of renal perfusion and exposure to nephrotoxic agents. Therapy is largely supportive, and prevention offers the best chance to decrease clinical impact.

Association between average mean arterial pressure and 30-day mortality in critically ill patients with sepsis and primary hypertension: a retrospective analysis

Sepsis and hypertension pose significant health risks, yet the optimal mean arterial pressure (MAP) target for resuscitation remains uncertain. This study investigates the association between average MAP (a-MAP) within the initial 24 h of intensive care unit admission and clinical outcomes in patients with sepsis and primary hypertension using the Medical Information Mart for Intensive Care (MIMIC) IV database. Multivariable Cox regression assessed the association between a-MAP and 30-day mortality. Kaplan-Meier and log-rank analyses constructed survival curves, while restricted cubic splines (RCS) illustrated the nonlinear relationship between a-MAP and 30-day mortality. Subgroup analyses ensured robustness. The study involved 8,810 patients. Adjusted hazard ratios for 30-day mortality in the T1 group (< 73 mmHg) and T3 group (≥ 80 mmHg) compared to the T2 group (73-80 mmHg) were 1.25 (95% CI 1.09-1.43, P = 0.001) and 1.44 (95% CI 1.25-1.66, P < 0.001), respectively. RCS revealed a U-shaped relationship (non-linearity: P < 0.001). Kaplan-Meier curves demonstrated significant differences (P < 0.0001). Subgroup analysis showed no significant interactions. Maintaining an a-MAP of 73 to 80 mmHg may be associated with a reduction in 30-day mortality. Further validation through prospective randomized controlled trials is warranted.

Clinical Effectiveness and Safety of Colistin Sulphate in Treating Infections Caused by Carbapenem-Resistant Organisms and Analysis of Influencing Factors

Objective

To assess the efficacy and safety of colistin sulfate in treating infections caused by carbapenem-resistant organisms (CRO) and to analyze potential factors impacting its effectiveness.

Methods

In this retrospective study, medical records of CRO-infected patients from June 2020 to June 2023 were analyzed, divided into effective and ineffective treatment groups, and compared for clinical outcomes and adverse reactions. Multifactorial logistic regression and ROC curve analysis were used to identify influencing factors.

Results

The study included 226 patients, with 124 in the effective treatment group and 102 in the ineffective group. A total of 293 CRO strains were cultured. The clinical efficacy rate of colistin sulfate was 54.87%, the microbiological efficacy rate 46.46%, and the hospital mortality rate 20.80%, with nephrotoxicity observed in 11.50% of patients. Multifactorial analysis identified APACHE II scores and vasoactive drug use as independent predictors of ineffective treatment, while treatment duration and albumin levels predicted effective treatment. ROC analysis indicated that albumin levels >34 g/L, APACHE II scores <13, and treatment duration >10 days correlated with better clinical efficacy.

Conclusion

Colistin sulfate is both safe and effective in clinical settings. Factors such as treatment duration, albumin levels, APACHE II scores, and vasoactive drug use independently affect its clinical efficacy, providing valuable guidance for its informed clinical application.

Role of G protein coupled receptors in acute kidney injury

Acute kidney injury (AKI) is a clinical condition characterized by a rapid decline in kidney function, which is associated with local inflammation and programmed cell death in the kidney. The G protein-coupled receptors (GPCRs) represent the largest family of signaling transduction proteins in the body, and approximately 40% of drugs on the market target GPCRs. The expressions of various GPCRs, prostaglandin receptors and purinergic receptors, to name a few, are significantly altered in AKI models. And the role of GPCRs in AKI is catching the eyes of researchers due to their distinctive biological functions, such as regulation of hemodynamics, metabolic reprogramming, and inflammation. Therefore, in this review, we aim to discuss the role of GPCRs in the pathogenesis of AKI and summarize the relevant clinical trials involving GPCRs to assess the potential of GPCRs and their ligands as therapeutic targets in AKI and the transition to AKI-CKD.

Use of Cefiderocol in Adult Patients: Descriptive Analysis from a Prospective, Multicenter, Cohort Study

INTRODUCTION

Cefiderocol is a siderophore cephalosporin showing activity against various carbapenem-resistant Gram-negative bacteria (CR-GNB). No data currently exist about real-world use of cefiderocol in terms of types of therapy (e.g., empirical or targeted, monotherapy or combined regimens), indications, and patient characteristics.

METHODS

In this multicenter, prospective study, we aimed at describing the use of cefiderocol in terms of types of therapy, indications, and patient characteristics.

RESULTS

Cefiderocol was administered as empirical and targeted therapy in 27.5% (55/200) and 72.5% (145/200) of cases, respectively. Overall, it was administered as monotherapy in 101/200 cases (50.5%) and as part of a combined regimen for CR-GNB infections in the remaining 99/200 cases (49.5%). In multivariable analysis, previous isolation of carbapenem-resistant Acinetobacter baumannii odds ratio (OR) 2.56, with 95% confidence interval (95% CI) 1.01-6.46, p = 0.047] and previous hematopoietic stem cell transplantation (OR 8.73, 95% CI 1.05-72.54, p = 0.045) were associated with administration of cefiderocol as part of a combined regimen, whereas chronic kidney disease was associated with cefiderocol monotherapy (OR 0.38 for combined regimen, 95% CI 0.16-0.91, p = 0.029). Cumulative 30-day mortality was 19.8%, 45.0%, 20.7%, and 22.7% in patients receiving targeted cefiderocol for infections by Enterobacterales, A. baumannii, Pseudomonas aeruginosa, and any metallo-β-lactamase producers, respectively.

CONCLUSIONS

Cefiderocol is mainly used for targeted treatment, although empirical therapies account for more than 25% of prescriptions, thus requiring dedicated standardization and guidance. The almost equal distribution of cefiderocol monotherapy and cefiderocol-based combination therapies underlines the need for further study to ascertain possible differences in efficacy between the two approaches.

Natural polysaccharides as promising reno-protective agents for the treatment of various kidney injury

Renal injury, a prevalent clinical outcome with multifactorial etiology, imposes a substantial burden on society. Currently, there remains a lack of effective management and treatments. Extensive research has emphasized the diverse biological effects of natural polysaccharides, which exhibit promising potential for mitigating renal damage. This review commences with the pathogenesis of four common renal diseases and the shared mechanisms underlying renal injury. The renoprotective roles of polysaccharides in vivo and in vitro are summarized in the following five aspects: anti-oxidative stress effects, anti-apoptotic effects, anti-inflammatory effects, anti-fibrotic effects, and gut modulatory effects. Furthermore, we explore the structure-activity relationship and bioavailability of polysaccharides in relation to renal injury, as well as investigate their utility as biomaterials for alleviating renal injury. The clinical experiments of polysaccharides applied to patients with chronic kidney disease are also reviewed. Broadly, this review provides a comprehensive perspective on the research direction of natural polysaccharides in the context of renal injury, with the primary aim to serve as a reference for the clinical development of polysaccharides as pharmaceuticals and prebiotics for the treatment of kidney diseases.

Diuretic response after neonatal cardiac surgery: a report from the NEPHRON collaborative

BACKGROUND

Multicenter early diuretic response (DR) analysis of single furosemide dosing following neonatal cardiac surgery is lacking to inform whether early DR predicts adverse clinical outcomes.

METHODS

We performed a retrospective cohort study utilizing data from the NEPHRON registry. Random forest machine learning generated receiver operating characteristic-area under the curve (ROC-AUC) and odds ratios for mechanical ventilation (MV) and respiratory support (RS). Prolonged MV and RS were defined using ≥ 90th percentile of observed/expected ratios. Secondary outcomes were prolonged CICU and hospital length of stay (LOS) and kidney failure (stage III acute kidney injury (AKI), peritoneal dialysis, and/or continuous kidney replacement therapy on postoperative day three) assessed using covariate-adjusted ROC-AUC curves.

RESULTS

A total of 782 children were included. Cumulative urine output (UOP) metrics were lower in prolonged MV and RS patients, but DR poorly predicted prolonged MV (highest AUC 0.611, OR 0.98, sensitivity 0.67, specificity 0.53, p = 0.006, 95% OR CI 0.96-0.99 for cumulative 6-h UOP) and RS (highest AUC 0.674, OR 0.94, sensitivity 0.75, specificity 0.54, p < 0.001, 95% CI 0.91-0.97 UOP between 3 and 6 h). Secondary outcome results were similar. DR had fair discrimination for kidney failure (AUC 0.703, OR 0.94, sensitivity 0.63, specificity 0.71, 95% OR CI 0.91-0.98, p < 0.001, cumulative 6-h UOP).

CONCLUSIONS

Early DR poorly discriminated patients with prolonged MV, RS, and LOS in this cohort, though it may identify severe postoperative AKI phenotype. Future work is warranted to determine if early DR or late postoperative DR later, in combination with other AKI metrics, may identify a higher-risk phenotype.

A Predictive Nomogram of In-Hospital Mortality After 48 h for Atrial Fibrillation Patients in the Coronary Care Unit

BACKGROUND

Patients with atrial fibrillation (AF) suffer a higher risk of death, and it is necessary to develop prediction tools for mortality risk in critically ill patients with AF. This study aimed to develop a novel predictive nomogram of in-hospital mortality after 48 h in the coronary care unit (CCU) for patients with AF.

METHODS

We collected information on CCU patients with AF from the "Medical Information Mart for Intensive Care-III" database and developed a nomogram model for predicting the all-cause mortality risk after 48 h in the hospital. Key variables were selected by univariate logistic and least absolute shrinkage and selection operator regression. The independent predictors with p < 0.05 were screened out by multivariate logistic regression. A predictive nomogram was constructed using these independent predictors, and the model calibration and discrimination were evaluated.

RESULTS

This study finally enrolled 1248 CCU patients with AF, and the in-hospital mortality was 17% (209/1248). The predictive nomogram was constructed by 13 selected independent predictors, including age, smoking status, acute kidney injury, chronic obstructive pulmonary disease, ventricular arrhythmia, shock, urea, red cell distribution width, leucocytosis, continuous renal replacement therapy, continuous positive airway pressure, anticoagulation, and heart rate. The area under the curve of the nomogram was 0.803 (95% confidence interval 0.771-0.835). The nomogram was verified to have good accuracy and calibration.

CONCLUSIONS

This study developed a novel nomogram containing age, acute kidney injury, and heart rate that can be a good predictor of potential in-hospital mortality after 48 h in CCU patients with AF.

The High-Sensitivity C-Reactive Protein to High-Density Lipoprotein Cholesterol Ratio and the Risk of Contrast-Induced Acute Kidney Injury in Patients Undergoing Percutaneous Coronary Intervention

Background

The high-sensitivity C-reactive protein to high-density lipoprotein cholesterol ratio (CHR) is a novel biomarker associated with coronary artery disease (CAD) risk. This study aimed to analyze the relationship between CHR and contrast-induced acute kidney injury (CI-AKI).

Methods

This retrospective cross-sectional research included 10,917 individuals who underwent PCI. CI-AKI was diagnosed using the Kidney Disease: Improving Global Outcomes (KIDIGO) standard. Univariate and multivariable logistic regression analyses were conducted to examine the association between CHR and CI-AKI, followed by a receiver operating characteristic (ROC) curve of participants to assess the clinical diagnostic performance of CHR on CI-AKI.

Results

A total of 1037 patients (9.50%) developed CI-AKI after PCI. The age of individuals averaged 64.1 ± 11.1 years old, with 2511 females (23.0%). A multivariate logistic regression study revealed that higher CHR levels were linked to higher CI-AKI incidence rates ([Q4 vs. Q1]: odds ratio (OR) = 1.89, 95% confidence interval (CI) [1.42 to 2.54], p < 0.001). A restricted cubic spline analysis revealed a linear association between CHR and CI-AKI. ROC analysis indicated that CHR was an excellent predictor of CI-AKI (area under ROC curve = 0.606, 95% CI [0.588 to 0.624]).

Conclusions

A high CHR level is strongly associated with increased CI-AKI incidence, suggesting that CHR may be an independent risk factor for CI-AKI.

Clinical Trial registration

NCT05050877. https://clinicaltrials.gov/study/NCT05050877?tab=results.

Risk factors predicting the need for intensive care unit admission within forty-eight hours of emergency department presentation: A case-control study

BACKGROUND

Patients admitted from the emergency department to the wards, who progress to a critically unwell state, may require expeditious admission to the intensive care unit. It can be argued that earlier recognition of such patients, to facilitate prompt transfer to intensive care, could be linked to more favourable clinical outcomes. Nevertheless, this can be clinically challenging, and there are currently no established evidence-based methods for predicting the need for intensive care in the future.

OBJECTIVES

We aimed to analyse the emergency department data to describe the characteristics of patients who required an intensive care admission within 48 h of presentation. Secondly, we planned to test the feasibility of using this data to identify the associated risk factors for developing a predictive model.

METHODS

We designed a retrospective case-control study. Cases were patients admitted to intensive care within 48 h of their emergency department presentation. Controls were patients who did not need an intensive care admission. Groups were matched based on age, gender, admission calendar month, and diagnosis. To identify the associated variables, we used a conditional logistic regression model.

RESULTS

Compared to controls, cases were more likely to be obese, and smokers and had a higher prevalence of cardiovascular (39 [35.1%] vs 20 [18%], p = 0.004) and respiratory diagnoses (45 [40.5%] vs 25 [22.5%], p = 0.004). They received more medical emergency team reviews (53 [47.8%] vs 24 [21.6%], p < 0.001), and more patients had an acute resuscitation plan (31 [27.9%] vs 15 [13.5%], p = 0.008). The predictive model showed that having acute resuscitation plans, cardiovascular and respiratory diagnoses, and receiving medical emergency team reviews were strongly associated with having an intensive care admission within 48 h of presentation.

CONCLUSIONS

Our study used emergency department data to provide a detailed description of patients who had an intensive care unit admission within 48 h of their presentation. It demonstrated the feasibility of using such data to identify the associated risk factors to develop a predictive model.

Life-Threatening Transfusion Reaction in Postoperative Total Knee Arthroplasty: A Unique Case and Comprehensive Insights

Introduction

Blood transfusions are essential for managing blood loss in surgical patients but can lead to life-threatening reactions. This report presents a severe transfusion reaction in a postoperative total knee arthroplasty (TKA) patient, emphasizing the need for vigilant monitoring and timely intervention.

Case Report

A 70-year-old male with a history of bilateral knee pain underwent right-sided TKA. Preoperative evaluations were normal. Post-surgery, significant blood loss led to a one-pint packed red blood cell transfusion. The patient developed fever, chills, palpitations, and rapid breathing, indicating a transfusion reaction. Despite immediate treatment, the patient's condition deteriorated, requiring ICU admission. Complications included acute kidney injury (AKI), metabolic acidosis, thrombocytopenia, pleural effusion, and aspiration pneumonitis. Multiple organ dysfunction syndrome (MODS) developed, necessitating hemodialysis. Despite comprehensive care, the patient passed away.

Conclusion

This case highlights the critical need for rigorous pre-transfusion screening, vigilant monitoring, and immediate intervention in managing severe transfusion reactions in postoperative TKA patients. Comprehensive patient care strategies are essential to mitigate the multifocal complications associated with transfusion reactions. Additional research is needed to understand and prevent such life-threatening reactions.

Association between hydroxyethyl starch 130/0.4 administration during noncardiac surgery and postoperative acute kidney injury: A propensity score-matched analysis of a large cohort in China

STUDY OBJECTIVE

The use of hydroxyethyl starch 130/0.4 has been linked to renal injury in critically ill patients, but its impact on surgical patients remains uncertain.

DESIGN

A retrospective cohort study.

SETTING

This study was conducted at one tertiary care hospital in China.

PATIENTS

We evaluated the records of 51,926 Chinese adults who underwent noncardiac surgery from 2013 to 2022. Patients given a combination of hydroxyethyl starch 130/0.4 and crystalloids were propensity-matched at a 1: 1 ratio of baseline characteristics to patients given only crystalloids (11,725 pairs).

INTERVENTIONS

Eligible patients were divided into those given a combination of hydroxyethyl starch 130/0.4 and crystalloid during surgery and a reference crystalloid group consisting of patients who were not given any colloid.

MEASUREMENTS

The primary outcome was the incidence of acute kidney injury. Secondarily, acute kidney injury stage, need for renal replacement therapy, intensive care unit transfer rate, and duration of postoperative hospitalization were considered.

MAIN RESULTS

After matching, hydroxyethyl starch use [8.5 (IQR: 7.5-10.0) mL/kg] did not increase the incidence of acute kidney injury compared with that in the crystalloid group [2.0 vs. 2.2%, OR: 0.90 (0.74-1.08), P = 0.25]. Nor did hydroxyethyl starch use worsen acute kidney injury stage [OR 0.90 (0.75-1.08), P = 0.26]. No significant differences between the fluid groups were observed in renal replacement therapy [OR 0.60 (0.41-0.90), P = 0.02)] or intensive care unit transfers [OR 1.02 (0.95-1.09), P = 0.53] after Bonferroni correction. Even in a subset of patients at high risk of renal injury, hydroxyethyl starch use was not associated with worse outcomes.

CONCLUSIONS

Hydroxyethyl starch 130/0.4 use was not significantly associated with a greater incidence of postoperative acute kidney injury compared to receiving crystalloid solutions only.

Creatinine and Cystatin C: A Measure of Renal Function in Men With Testosterone-Induced Muscle Hypertrophy

Creatinine (Cr) is often used as a standalone gold standard marker of kidney function. Cystatin C (Cys C) is a less physiologically labile marker of renal function, particularly in certain subgroups. Herein, we analyze trends in cystatin C as compared to creatinine in men on testosterone replacement therapy with varying body mass indices and percent body fat (PBF). This retrospective analysis observes 227 men with testosterone-induced muscle hypertrophy who visited a men's health tertiary care clinic. All participants were characterized as competitive or recreational athletes. In patients with a normal body mass index (BMI), there was no clinically significant correlation between Cr and Cys C. Slight correlation was seen with overweight (R2 = .27) patients (p < .0001) and obese (R2 = .29) patients (p < .0001). Patients with PBF of 0%-10% (n = 22) exhibited minimal (R2 = .23) positive correlation between Cys C and Cr (p = .03). Positive correlation between Cys C and Cr in patients with PBF of 10%-20% was clinically negligible (R2 = .17, n = 87), modest (R2 = .49) in patients with PBF of 20%-30% (n = 42), and evident (R2 = 1.00) in patients >30% (n = 3) (p < .0001, respectively). Cystatin C measurements display less variance compared with creatinine at differing BMI distinctions. At the upper limit of BMI or PBF in our patient population, cystatin C exhibits minimal to moderate variability compared with creatinine.

Metabolic reprogramming in septic acute kidney injury: pathogenesis and therapeutic implications

Acute kidney injury (AKI) is a frequent and severe complication of sepsis and is characterized by significant mortality and morbidity. However, the pathogenesis of septic acute kidney injury (S-AKI) remains elusive. Metabolic reprogramming, which was originally referred to as the Warburg effect in cancer, is strongly related to S-AKI. At the onset of sepsis, both inflammatory cells and renal parenchymal cells, such as macrophages, neutrophils and renal tubular epithelial cells, undergo metabolic shifts toward aerobic glycolysis to amplify proinflammatory responses and fortify cellular resilience to septic stimuli. As the disease progresses, these cells revert to oxidative phosphorylation, thus promoting anti-inflammatory reactions and enhancing functional restoration. Alterations in mitochondrial dynamics and metabolic reprogramming are central to the energetic changes that occur during S-AKI. In this review, we summarize the current understanding of the pathogenesis of metabolic reprogramming in S-AKI, with a focus on each cell type involved. By identifying relevant key regulatory factors, we also explored potential metabolic reprogramming-related therapeutic targets for the management of S-AKI.

Outcomes of extracorporeal membrane oxygenation cannulation strategy in lung transplantation: A retrospective cohort study

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) with different cannulation strategies is determined according to surgical position and patient condition. However, no cannulation guidelines have been proposed. This retrospective study assessed the outcomes of diverse ECMO cannulation strategies in patients undergoing lung transplantation (LTx).

METHODS

Data of patients undergoing intraoperative veno-arterial ECMO-assisted LTx were retrospectively collected from December 1st, 2015 to October 31st, 2021. Patients were classified into three groups based on the different cannulation strategies: femoral artery-femoral vein (F-F)-ECMO, axillary artery-femoral vein (A-F)-ECMO, and ascending aorta-femoral vein (AAO-F)-ECMO. The F-F-ECMO, A-F-ECMO, and AAO-F-ECMO groups comprised 34, 44, and 30 patients, respectively.

MAIN RESULTS

The AAO-F-ECMO group exhibited a significantly shorter duration of postoperative ECMO therapy (3 vs. 2 vs. 0 days, P < 0.01).the level of postoperative proBNP was lower on the third and seventh days (P < 0.001). AAO-F-ECMO patients had a significantly lower incidence of postoperative infections, heart failure, and bleeding (P < 0.05). Similar outcomes were observed in postoperative survival rates among the three groups (P > 0.05).

CONCLUSIONS

Ascending aorta-femoral vein ECMO can provide sufficient and effective aerobic blood to perfuse organs with fewer side effects than cannulation in the femoral artery-femoral vein or axillary artery-femoral vein.

Artificial intelligence algorithms permits rapid acute kidney injury risk classification of patients with acute myocardial infarction

Objective

This study aimed to develop and validate several artificial intelligence (AI) models to identify acute myocardial infarction (AMI) patients at an increased risk of acute kidney injury (AKI) during hospitalization.

Methods

Included were patients diagnosed with AMI from the Medical Information Mart for Intensive Care (MIMIC) III and IV databases. Two cohorts of AMI patients from Changzhou Second People's Hospital and Xuzhou Center Hospital were used for external validation of the models. Patients' demographics, vital signs, clinical characteristics, laboratory results, and therapeutic measures were extracted. Totally, 12 AI models were developed. The area under the receiver operating characteristic curve (AUC) were calculated and compared.

Results

AKI occurred during hospitalization in 1098 (28.3 %) of the 3882 final enrolled patients, split into training (3105) and test (777) sets randomly. Among them, Random Forest (RF), C5.0 and Bagged CART models outperformed the other models in both the training and test sets. The AUCs for the test set were 0.754, 0.734 and 0.730, respectively. The incidence of AKI was 9.8 % and 9.5 % in 2202 patients in the Changzhou cohort and 807 patients in the Xuzhou cohort with AMI, respectively. The AUCs for patients in the Changzhou cohort were RF, 0.761; C5.0, 0.733; and bagged CART, 0.725, respectively, and Xuzhou cohort were RF, 0.799; C5.0, 0.808; and bagged CART, 0.784, respectively.

Conclusion

Several machines learning-based prediction models for AKI after AMI were developed and validated. The RF, C5.0 and Bagged CART model performed robustly in identifying high-risk patients earlier.

Clinical trial approval statement

This Trial was registered in the Chinese clinical trials registry: ChiCTR1800014583. Registered January 22, 2018 (http://www.chictr.org.cn/searchproj.aspx).

Development and validation of a nomogram to predict the risk of vancomycin-related acute kidney injury in critical care patients

Background

Vancomycin-associated acute kidney injury (AKI) leads to underestimated morbidity in the intensive care unit (ICU). It is significantly important to predict its occurrence in advance. However, risk factors and nomograms to predict this AKI are limited.

Methods

This was a retrospective analysis of two databases. A total of 1,959 patients diagnosed with AKI and treated with vancomycin were enrolled from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. According to the 7:3 ratio, the training set (n = 1,372) and the internal validation set (n = 587) were randomly allocated. The external validation set included 211 patients from the eICU Collaborative Research Database (eICU). Next, to screen potential variables, the least absolute shrinkage and selection operator (LASSO) regression was utilized. Subsequently, the nomogram was developed by the variables of the selected results in the multivariable logistic regression. Finally, discrimination, calibration, and clinical utility were evaluated to validate the nomogram.

Results

The constructed nomogram showed fine discrimination in the training set (area under the receiver operator characteristic curve [AUC] = 0.791; 95% confidence interval [CI]: 0.758-0.823), internal validation set (AUC = 0.793; 95% CI: 0.742-0.844), and external validation set (AUC = 0.755; 95% CI: 0.663-0.847). Moreover, it also well demonstrated calibration and clinical utility. The significant improvement (P < 0.001) in net reclassification improvement (NRI) and integrated differentiation improvement (IDI) confirmed that the predictive model outperformed others.

Conclusion

This established nomogram indicated promising performance in determining individual AKI risk of vancomycin-treated critical care patients, which will be beneficial in making clinical decisions.

Acute Kidney Injury in Rhabdomyolysis: A 5-Year Children's Hospital Network Study

Rhabdomyolysis is a skeletal muscle injury that can cause myoglobinuria and acute kidney injury (AKI). Risk factors for AKI in children are not clearly understood with no standardized treatment guidelines for rhabdomyolysis. Our study explores factors associated with AKI and management of pediatric patients with rhabdomyolysis. Medical records from a children's hospital network over a 5-year period were retrospectively reviewed. The results are described with respect to the presence or absence of AKI. Of the 112 patients who met the inclusion criteria, AKI incidence was 7.1% (n = 8), with all affected patients having exertional etiology. The overall mean age was 13.5 years; patients without AKI were younger than patients with AKI (13.3 versus 17; p < 0.001). Using regression models for hypothesis generation, we found that patients with AKI were more likely to be older (OR = 1.44, 95%CI [1.11-2.19]; p = 0.03), have myoglobinuria (OR = 22.98, 95%CI [2.05-432.48]; p = 0.02), and have received intravenous bicarbonate (OR = 16.02, 95%CI [1.44-228.69]; p = 0.03). In our study, AKI was uncommon and associated with older age, myoglobinuria and bicarbonate treatment. Larger, prospective studies are needed to further understand AKI risk factors and optimal management of pediatric rhabdomyolysis.

Predictive value of perioperative NT-proBNP levels for acute kidney injury in patients with compromised renal function undergoing cardiac surgery: a case control study

BACKGROUND

Acute kidney injury (AKI) significantly increases morbidity and mortality following cardiac surgery, especially in patients with pre-existing renal impairments. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a marker of cardiac stress and dysfunction, conditions often exacerbated during cardiac surgery and prevalent in chronic kidney disease (CKD) patients. Elevated NT-proBNP levels can indicate underlying cardiac strain, hemodynamic instability and volume overload. This study evaluated the association between perioperative changes in NT-proBNP levels and the incidence of AKI in this particular patient group.

METHODS

This retrospective study involved patients with impaired renal function (eGFR 15-60 ml/min/1.73 m²) who underwent cardiac surgery from July to December 2022. It analyzed the association between the ratio of preoperative and ICU admittance post-surgery NT-proBNP levels and the development of AKI and AKI stage 2-3, based on KDIGO criteria, using multivariate logistic regression models. Restricted cubic spline analysis assessed non-linear associations between NT-proBNP and endpoints. Subgroup analysis was performed to assess the heterogeneity of the association between NT-proBNP and endpoints in subgroups.

RESULTS

Among the 199 participants, 116 developed postoperative AKI and 16 required renal replacement therapy. Patients with AKI showed significantly higher postoperative NT-proBNP levels compared to those without AKI. Decreased baseline eGFR and increased post/preoperative NT-proBNP ratios were associated with higher AKI risk. Specifically, the highest quantile post/preoperative NT-proBNP ratio indicated an approximately seven-fold increase in AKI risk and a ninefold increase in AKI stage 2-3 risk compared to the lowest quantile. The area under the receiver operating characteristic curve for predicting AKI and AKI stage 2-3 using NT-proBNP were 0.63 and 0.71, respectively, demonstrating moderate accuracy. Subgroup analysis demonstrated that the positive association between endpoints and logarithmic transformed post/preoperative NT-proBNP levels was consistently robust in subgroup analyses stratified by age, sex, surgery, CPB application, hypertension, diabetes status and fluid balance.

CONCLUSION

Perioperative NT-proBNP level changes are predictive of postoperative AKI in patients with pre-existing renal deficiencies undergoing cardiac surgery, aiding in risk assessment and patient management.

Understanding fluid dynamics and renal perfusion in acute kidney injury management

Acute kidney injury (AKI) is associated with an increased risk of morbidity, mortality, and healthcare expenditure, posing a major challenge in clinical practice, and affecting about 50% of patients in the intensive care unit (ICU), particularly the elderly and those with pre-existing chronic comorbidities. In health, intra-renal blood flow is maintained and auto-regulated within a wide range of renal perfusion pressures (60-100 mmHg), mediated predominantly through changes in pre-glomerular vascular tone of the afferent arteriole in response to changes of the intratubular NaCl concentration, i.e. tubuloglomerular feedback. Several neurohormonal processes contribute to regulation of the renal microcirculation, including the sympathetic nervous system, vasodilators such as nitric oxide and prostaglandin E2, and vasoconstrictors such as endothelin, angiotensin II and adenosine. The most common risk factors for AKI include volume depletion, haemodynamic instability, inflammation, nephrotoxic exposure and mitochondrial dysfunction. Fluid management is an essential component of AKI prevention and management. While traditional approaches emphasize fluid resuscitation to ensure renal perfusion, recent evidence urges caution against excessive fluid administration, given AKI patients' susceptibility to volume overload. This review examines the main characteristics of AKI in ICU patients and provides guidance on fluid management, use of biomarkers, and pharmacological strategies.

Multiparametric MRI based assessment of kidney injury in a mouse model of ischemia reperfusion injury

Kidney diseases pose a global healthcare burden, with millions requiring renal replacement therapy. Ischemia/reperfusion injury (IRI) is a common pathology of acute kidney injury, causing hypoxia and subsequent inflammation-induced kidney damage. Accurate detection of acute kidney injury due to IRI is crucial for timely intervention. We used longitudinal, multi-parametric magnetic resonance imaging (MRI) employing arterial spin labelling (ASL), diffusion weighted imaging (DWI), and dynamic contrast enhanced (DCE)-MRI to assess IRI induced changes in both the injured and healthy contralateral kidney, in a unilateral IRI mouse model (n = 9). Multi-parametric MRI demonstrated significant differences in kidney volume (p = 0.001), blood flow (p = 0.002), filtration coefficient (p = 0.038), glomerular filtration rate (p = 0.005) and apparent diffusion coefficient (p = 0.048) between the injured kidney and contralateral kidney on day 1 post-IRI surgery. Identification of the injured kidney using principal component analysis including most of the imaging parameters demonstrated an area under the curve (AUC) of 0.97. These results point to the utility of multi-parametric MRI in early detection of IRI-induced kidney damage suggesting that the combination of various MRI parameters may be suitable for monitoring the extent of injury in this model.

Association of alactic base excess with in-hospital mortality in patients with acute myocardial infarction: a retrospective cohort study

BACKGROUND

Alactic base excess (ABE) is a novel biomarker to evaluate the renal capability of handling acid-base disturbances, which has been found to be associated with adverse prognosis of sepsis and shock patients. This study aimed to evaluate the association between ABE and the risk of in-hospital mortality in patients with acute myocardial infarction (AMI).

METHODS

This retrospective cohort study collected AMI patients' clinical data from the Medical Information Mart for Intensive Care (MIMIC)-IV database. The outcome was in-hospital mortality after intensive care unit (ICU) admission. Univariate and multivariate Cox proportional hazards models were performed to assess the association of ABE with in-hospital mortality in AMI patients, with hazard ratios (HRs) and 95% confidence intervals (CI). To further explore the association, subgroup analyses were performed based on age, AKI, eGFR, sepsis, and AMI subtypes.

RESULTS

Of the total 2779 AMI patients, 502 died in hospital. Negative ABE (HR = 1.26, 95%CI: 1.02-1.56) (neutral ABE as reference) was associated with a higher risk of in-hospital mortality in AMI patients, but not in positive ABE (P = 0.378). Subgroup analyses showed that negative ABE was significantly associated with a higher risk of in-hospital mortality in AMI patients aged>65 years (HR = 1.46, 95%CI: 1.13-1.89), with eGFR<60 (HR = 1.35, 95%CI: 1.05-1.74), with AKI (HR = 1.32, 95%CI: 1.06-1.64), with ST-segment elevation acute myocardial infarction (STEMI) subtype (HR = 1.79, 95%CI: 1.18-2.72), and without sepsis (HR = 1.29, 95%CI: 1.01-1.64).

CONCLUSION

Negative ABE was significantly associated with in-hospital mortality in patients with AMI.

Incidence and risk factors for acute kidney injury after traumatic hemorrhagic shock: A 10-year retrospective cohort study

BACKGROUND

Acute kidney injury (AKI) is a common complication of traumatic hemorrhagic shock. The risk factors for AKI after traumatic hemorrhagic shock remain unclear. The aim of this study was to investigate the risk factors for AKI after traumatic hemorrhagic shock.

METHODS

This was a ten-year retrospective cohort study of patients who experienced traumatic hemorrhagic shock between January 2013 and April 2023. Patient characteristics and clinical data were recorded for 417 patients. The outcome was the occurrence of AKI, defined as a serum creatinine increase of ≥ 0.3 mg/dL (≥ 26.5 μmol/L) within 48 h, or an increase to 1.5 times the baseline, or a urine volume of < 0.5 mL/(kg h.). Risk factors for AKI were tested by logistic regression models.

RESULTS

The incidence of AKI after traumatic hemorrhagic shock was 29.3% (122/417 patients). Multivariable analysis revealed that the independent risk factors for AKI included age (OR, 1.048; 95% CI, 1.022-1.074; p < 0.001), B-type natriuretic peptide (OR, 1.002; 95% CI, 1.000-1.004; p = 0.041), sepsis (OR, 4.536; 95% CI, 1.651-12.462; p = 0.030) and acute myocardial injury (OR, 2.745; 95% CI, 1.027-7.342; p = 0.044). Road traffic accidents (OR, 0.202; 95% CI, 0.076-0.541; p = 0.001), mean arterial pressure (OR, 0.972; 95% CI, 0.950-0.995; p = 0.017), and base excess (OR, 0.842; 95% CI, 0.764-0.929; p = 0.001) were negatively correlated with AKI. The area under the receiver operating characteristic (ROC) curve for prediction by this model was 0.85 (95% CI, 0.81-0.90).

CONCLUSION

The incidence of AKI after traumatic hemorrhagic shock was 29.3% in our series. Indicators of blood perfusion, sepsis and acute myocardial injury may be independent risk factors for AKI after traumatic hemorrhagic shock. Early detection and effective intervention on these risk factors could reduce the occurrence of AKI and improve outcomes.

Using Domain Adaptation and Inductive Transfer Learning to Improve Patient Outcome Prediction in the Intensive Care Unit: Retrospective Observational Study

BACKGROUND

Accurate patient outcome prediction in the intensive care unit (ICU) can potentially lead to more effective and efficient patient care. Deep learning models are capable of learning from data to accurately predict patient outcomes, but they typically require large amounts of data and computational resources. Transfer learning (TL) can help in scenarios where data and computational resources are scarce by leveraging pretrained models. While TL has been widely used in medical imaging and natural language processing, it has been rare in electronic health record (EHR) analysis. Furthermore, domain adaptation (DA) has been the most common TL method in general, whereas inductive transfer learning (ITL) has been rare. To the best of our knowledge, DA and ITL have never been studied in-depth in the context of EHR-based ICU patient outcome prediction.

OBJECTIVE

This study investigated DA, as well as rarely researched ITL, in EHR-based ICU patient outcome prediction under simulated, varying levels of data scarcity.

METHODS

Two patient cohorts were used in this study: (1) eCritical, a multicenter ICU data from 55,689 unique admission records from 48,672 unique patients admitted to 15 medical-surgical ICUs in Alberta, Canada, between March 2013 and December 2019, and (2) Medical Information Mart for Intensive Care III, a single-center, publicly available ICU data set from Boston, Massachusetts, acquired between 2001 and 2012 containing 61,532 admission records from 46,476 patients. We compared DA and ITL models with baseline models (without TL) of fully connected neural networks, logistic regression, and lasso regression in the prediction of 30-day mortality, acute kidney injury, ICU length of stay, and hospital length of stay. Random subsets of training data, ranging from 1% to 75%, as well as the full data set, were used to compare the performances of DA and ITL with the baseline models at various levels of data scarcity.

RESULTS

Overall, the ITL models outperformed the baseline models in 55 of 56 comparisons (all P values <.001). The DA models outperformed the baseline models in 45 of 56 comparisons (all P values <.001). ITL resulted in better performance than DA in terms of the number of times and the margin with which it outperformed the baseline models. In 11 of 16 cases (8 of 8 for ITL and 3 of 8 for DA), TL models outperformed baseline models when trained using 1% data subset.

CONCLUSIONS

TL-based ICU patient outcome prediction models are useful in data-scarce scenarios. The results of this study can be used to estimate ICU outcome prediction performance at different levels of data scarcity, with and without TL. The publicly available pretrained models from this study can serve as building blocks in further research for the development and validation of models in other ICU cohorts and outcomes.

Navigating Hemolysis, Hemoglobin Toxicity, and Its Renal Implications in Cardiac Surgery

Cardiopulmonary bypass–induced hemolysis is linked to acute kidney injury in cardiac surgery. Emerging therapies targeting cell-free hemoglobin (CFHb), like haptoglobin, nitric oxide (NO), and antioxidants, show promise in reducing kidney injury, highlighting the need for further research.

Acute Kidney Injury in Children: A Focus for the General Pediatrician

Acute kidney injury (AKI) presents significant challenges in pediatric care, often remaining underrecognized. This paper provides an overview of pediatric AKI, highlighting its epidemiology, pathophysiology, diagnosis, predisposing conditions, and treatment. AKI in children stems from diverse causes, including renal tubular damage, vasoconstriction, and inflammation. Diagnosis relies on traditional markers such as serum creatinine and urine output, alongside emerging biomarkers such as Cystatin C, NGAL, KIM-1, IL-18, TIMP-2 and IGFBP7, urinary calprotectin, URBP4, L-FABP, and clusterin. Various pediatric conditions predispose to AKI, including type 1 diabetes, pneumonia, bronchiolitis, appendicitis, gastroenteritis, COVID-19, multisystem inflammatory syndrome, sickle cell disease, and malignancies. Treatment entails supportive care with fluid management and, in severe cases, renal replacement therapy. Timely recognition and management are essential to mitigating adverse outcomes. Enhanced awareness and integration of novel biomarkers could improve pediatric AKI care, warranting further research for better diagnosis and management.

Post cardiotomy extracorporeal membrane oxygenation in pediatric patients: Results and neurodevelopmental outcomes

BACKGROUND

The increasing complexity of congenital cardiac surgery has led to greater utilization of extracorporeal membrane oxygenation (ECMO) support for children post-surgery. This study aims to identify risk factors for mortality and brain injury in pediatric patients requiring post-cardiotomy ECMO and to evaluate their neurological outcomes.

METHODS

This retrospective study includes pediatric patients with congenital heart diseases who required ECMO after surgery. Risk factors for in-hospital mortality and brain injury were assessed. Neurodevelopmental status was determined using the Pediatric Cerebral Performance Category (PCPC) Scale at discharge and during follow-up.

RESULTS

Between October 2014 and May 2021, 2651 pediatric patients underwent cardiac surgery, with 90 (3.4%) requiring ECMO. The mean age was 0.6 years, ranging from 1 day to 13 years and 7 months. ECMO was implemented for 45 patients due to CPB weaning failure (NW-CPB), 24 due to postoperative low-cardiac output syndrome (LCOS), and 21 for extracorporeal cardiopulmonary resuscitation (E-CPR). ECMO weaning was achieved in 73 patients (81%), with an overall mortality rate of 36%. Pre-implant lactate levels (OR: 1.13, 95% CI: 1.03-1.25; p = 0.009) and peak bilirubin levels (OR: 1.04, 95% CI: 0.87-1.24; p = 0.69) were risk factors for in-hospital mortality. Survival rates were 79% for LCOS, 60% for NW-CPB, and 48% for E-CPR. Brain injury incidence was 33%, with E-CPR being a significant risk factor (p = 0.006) and NW-CPB being protective (p = 0.001). Follow-up in November 2023 showed significant improvement in neurodevelopmental status (p < 0.001).

CONCLUSION

Elevated pre-implant lactate and elevated bilirubin levels during ECMO are major risk factors for mortality. E-CPR is the primary risk factor for brain injury. Follow-up revealed significant improvements in neurodevelopmental outcomes.

Detection strip of anti-NGAL antibody coupled with fluorescent microspheres-A novel tool for reliable and accurate prediction of renal injury

OBJECTIVE

Neutrophil gelatinase-associated lipocalin (NGAL) has been identified by the International Nephrology Association (INA) as a promising biomarker for the early evaluation of renal injury. This study aimed to develop and evaluate NGAL test strips as a rapid, simple, and economical method for the early diagnosis of acute kidney injury (AKI).

METHODS

Recombinant prokaryotic expression vectors, purified NGAL protein, and anti-NGAL monoclonal antibodies were prepared. NGAL test strips were developed, and serum samples were collected from healthy individuals and patients with early-stage kidney injury at the Third Affiliated Hospital of Sun Yat-sen University between January 2023 and May 2024. Samples were tested using both the self-made strips and commercially available reagents.

RESULTS

The NGAL test strip comprised a conjugate pad containing 0.2 μL of fluorescent microspheres conjugated with anti-NGAL monoclonal antibody (McAb7#), a test line containing 1 mg/mL of a different anti-NGAL monoclonal antibody (McAb3#), and a control line containing 0.5 mg/mL of goat anti-mouse IgG. The test utilized 60 μL of sample (30 μL serum diluted with 30 μL of sample diluent) and was completed within 15 min at 25 °C and 35 %-85 % relative humidity. The developed strip accurately detected NGAL, demonstrating good linearity within the range of 0-160 ng/mL (R2 = 0.9943). The sensitivity and specificity of the NGAL strip for AKI diagnosis were 86.1 % and 78.8 %, respectively, comparable to the performance of commercially available testing reagents.

CONCLUSION

The developed test strip, utilizing anti-NGAL antibodies coupled with fluorescent microspheres, effectively detected trace amounts of NGAL protein in serum samples.

Prognostic value of neutrophil-to-monocyte/lymphocyte ratio for 28-day mortality in ICU sepsis patients: a retrospective cohort study

Background

Sepsis is a life-threatening condition that requires rapid assessment to reduce mortality. This study investigates the relationship between the Neutrophil-to-Monocyte/Lymphocyte Ratio (NMLR) upon ICU admission and 28-day mortality in sepsis patients.

Methods

A retrospective analysis was performed using clinical data from sepsis patients in the Medical Information Mart for Intensive Care IV (MIMIC-IV). Multivariate logistic regression, sensitivity analyses, and Restricted Cubic Spline (RCS) models were employed to explore the relationship between ICU admission NMLR and 28-day mortality. Kaplan-Meier method and inverse probability weighting (IPW) were used to adjust for confounders and estimate survival outcomes. Receiver operating characteristic (ROC) curve evaluating the predictive value of NLMR for 28-day mortality in ICU sepsis patients. Subgroup analyses considered factors like age, sex, race, comorbidities, and disease severity.

Results

In total, 8,710 patients were included. Increased NMLR was associated with higher 28-day all-cause mortality, confirmed by multiple logistic regression models. In Model 3, after adjusting for confounders, each standard deviation increase in NMLR was associated with a 1.5% increase in 28-day mortality risk. Kaplan-Meier and IPW survival analyses showed higher 28-day all-cause mortality in patients with elevated NMLR levels at ICU admission compared to those with lower levels (p < 0.0001, p = 0.031). RCS models suggested a potential non-linear relationship between NMLR and 28-day mortality. ROC curve for the NMLR model, with an AUC of 0.658 (95% CI: 0.642-0.673). Sensitivity analyses confirmed the association even after excluding patients with myocardial infarction and severe liver disease.

Conclusion

Elevated NMLR at ICU admission is significantly associated with increased 28-day all-cause mortality in sepsis patients, suggesting its potential as an early prognostic indicator for risk assessment and intervention.

Advancements in Trauma-Induced Acute Kidney Injury: Diagnostic and Therapeutic Innovations

Acute kidney injury following trauma impacts patient recovery critically, necessitating an integrated approach to emergency care and nephrology. This review aims to provide a comprehensive understanding of trauma-induced nephropathy, highlighting recent advancements in pathophysiological insights, diagnostic techniques, and strategic interventions. Our key findings emphasize the role of biomarkers, like Neutrophil Gelatinase-Associated Lipocalin and Liver Fatty Acid-Binding Protein, and imaging techniques, such as contrast-enhanced ultrasound, in early AKI detection. Preventive strategies, including aggressive fluid resuscitation, avoidance of nephrotoxic agents, and hemodynamic optimization, are essential for mitigating AKI progression. Integrating these approaches into trauma care frameworks aims to enhance patient outcomes and set a foundation for future research and clinical improvements.

Assessing the predictive value of elevated postoperative syndecan-1 levels for progressive acute kidney injury and kidney replacement therapy necessity in adult cardiac surgery patients

BACKGROUND

The development of acute kidney injury (AKI) post-cardiac surgery significantly increases patient morbidity and healthcare costs. Prior researches have established Syndecan-1 (SDC-1) as a potential biomarker for endothelial injury and subsequent acute kidney injury development. This study assessed whether postoperative SDC-1 levels could further predict AKI requiring kidney replacement therapy (AKI-KRT) and AKI progression.

METHODS

In this prospective study, 122 adult cardiac surgery patients, who underwent valve or coronary artery bypass grafting (CABG) or a combination thereof and developed AKI within 48 h post-operation from May to September 2021, were monitored for the progression to stage 2-3 AKI or the need for KRT. We analyzed the predictive value of postoperative serum SDC-1 levels in relation to multiple endpoints.

RESULTS

In the study population, 110 patients (90.2%) underwent cardiopulmonary bypass, of which thirty received CABG or combined surgery. Fifteen patients (12.3%) required KRT, and thirty-eight (31.1%) developed progressive AKI, underscoring the severe AKI incidence. Multivariate logistic regression indicated that elevated SDC-1 levels were independent risk factors for progressive AKI (OR = 1.006) and AKI-KRT (OR = 1.011). The AUROC for SDC-1 levels in predicting AKI-KRT and AKI progression was 0.892 and 0.73, respectively, outperforming the inflammatory cytokines. Linear regression revealed a positive correlation between SDC-1 levels and both hospital (β = 0.014, p = 0.022) and ICU stays (β = 0.013, p < 0.001).

CONCLUSION

Elevated postoperative SDC-1 levels significantly predict AKI progression and AKI-KRT in patients following cardiac surgery. The study's findings support incorporating SDC-1 level monitoring into post-surgical care to improve early detection and intervention for severe AKI.

Impact of body mass index on mortality outcomes in intensive care patients with Staphylococcus aureus sepsis: A retrospective analysis

BACKGROUND

Evidence associating body mass index (BMI) with the prognosis of Staphylococcus aureus sepsis remains scarce.

OBJECTIVE

To explore the association between BMI and clinical outcomes in intensive care units patients with Staphylococcus aureus sepsis.

METHODS

A retrospective analysis of patients with Staphylococcus aureus sepsis was conducted using the MIMIC-IV database from the Critical Care Medicine Information. Data were collected within the first 24 hours of intensive care units admission. The primary endpoint was 28-day mortality. The association between BMI and 28-day all-cause mortality was assessed using multivariable logistic regression, subgroup analyses, restricted cubic spline curves and Kaplan-Meier survival analysis.

RESULTS

The study included 2,295 patients with an average age of 63.5 (16.1) years, 60.2% of whom were male. Multivariate analysis revealed that each 1 kg/m2 increase in BMI was linked to a 2.8% decrease in the risk of 28-day mortality (adjusted OR = 0.972, 95% CI: 0.955-0.990, P = 0.002). Patients in the medium and high BMI categories had significantly lower risks of 28-day mortality compared to those in the low BMI group (OR [95% CI] 0.650 [0.474-0.891]; OR [95% CI] 0.516 [0.378-0.705]; P trend < 0.0001). The RCS model showed a non-linear association between BMI and 28-day mortality (P = 0.014). Kaplan-Meier analysis showed that patients with elevated BMI had lower 28-day mortality (P < 0.0001). Notably, significant interactions between AKI and SOFA with BMI were observed (P<0.05).

CONCLUSION

Increased BMI is associated with a reduced risk of 28-day all-cause mortality in patients with Staphylococcus aureus sepsis.

Maintenance of beta-blockers and cardiac surgery-related outcomes: a prospective propensity-matched multicentre analysis

BACKGROUND

We investigated the effects of maintaining beta-blockers on the day of surgery on the incidence of atrial fibrillation and postoperative acute kidney injury (AKI) in patients undergoing cardiac surgery.

METHODS

We conducted a multicentre prospective observational study with propensity matching on patients treated with beta-blockers. We collected their baseline patient characteristics, comorbidities, and operative and postoperative outcomes. The endpoints were postoperative atrial fibrillation and AKI after cardiac surgery.

RESULTS

Of the 1789 included patients, propensity matching led to 583 patients in each group. Maintenance of beta-blockers was not associated with a reduced risk of atrial fibrillation (odds ratio: 0.86 [95% confidence interval 0.66-1.14], P=0.335; 141 patients [24.2%] vs 126 patients [21.6%]). Sensitivity analysis did not demonstrate association between beta-blocker maintenance and atrial fibrillation after cardiac surgery (odds ratio: 0.93 [95% confidence interval: 0.72-1.22], P=0.625). Maintenance of beta-blockers was associated with a higher rate of norepinephrine use (415 [71.2%] vs 465 [79.8%], P=0.0001) and postoperative AKI (124 [21.3%] vs 159 [27.3%], P=0.0127). No statistically significant difference was observed in ICU length of stay.

CONCLUSIONS

Maintenance of beta-blockers on the day of surgery was not associated with a reduced incidence of postoperative atrial fibrillation. However, maintenance of beta-blockers was associated with increased usage of vasopressors, potentially contributing to adverse postoperative renal events.

CLINICAL TRIAL REGISTRATION

NCT04769752.

Acute normovolemic hemodilution in cardiac surgery: Rationale and design of a multicenter randomized trial

BACKGROUND

Minimizing the use of blood component can reduce known and unknown blood transfusion risks, preserve blood bank resources, and decrease healthcare costs. Red Blood Cell (RBC) transfusion is common after cardiac surgery and associated with adverse perioperative outcomes, including mortality. Acute normovolemic hemodilution (ANH) may reduce bleeding and the need for blood product transfusion after cardiac surgery. However, its blood-saving effect and impact on major outcomes remain uncertain.

METHODS

This is a single-blinded, multinational, pragmatic, randomized controlled trial with a 1:1 allocation ratio conducted in Tertiary and University hospitals. The study is designed to enroll patients scheduled for elective cardiac surgery with planned cardiopulmonary bypass (CPB). Patients are randomized to receive ANH before CPB or the best available treatment without ANH. We identified an ANH volume of at least 650 ml as the critical threshold for clinically relevant benefits. Larger ANH volumes, however, are allowed and tailored to the patient's characteristics and clinical conditions.

RESULTS

The primary outcome is the percentage of patients receiving RBCs transfusion from randomization until hospital discharge, which we hypothesize will be reduced from 35% to 28% with ANH. Secondary outcomes are all-cause 30-day mortality, acute kidney injury, bleeding complications, and ischemic complications.

CONCLUSION

The trial is designed to determine whether ANH can safely reduce RBC transfusion after elective cardiac surgery with CPB.

STUDY REGISTRATION

This trial was registered on ClinicalTrials.gov in April 2019 with the trial identification number NCT03913481.

Effects of IV fluid restriction according to site-specific intensity of standard fluid treatment-protocol

BACKGROUND

Variation in usual practice in fluid trials assessing lower versus higher volumes may affect overall comparisons. To address this, we will evaluate the effects of heterogeneity in treatment intensity in the Conservative versus Liberal Approach to Fluid Therapy of Septic Shock in Intensive Care trial. This will reflect the effects of differences in site-specific intensities of standard fluid treatment due to local practice preferences while considering participant characteristics.

METHODS

We will assess the effects of heterogeneity in treatment intensity across one primary (all-cause mortality) and three secondary outcomes (serious adverse events or reactions, days alive without life support and days alive out of hospital) after 90 days. We will classify sites based on the site-specific intensity of standard fluid treatment, defined as the mean differences in observed versus predicted intravenous fluid volumes in the first 24 h in the standard-fluid group while accounting for differences in participant characteristics. Predictions will be made using a machine learning model including 22 baseline predictors using the extreme gradient boosting algorithm. Subsequently, sites will be grouped into fluid treatment intensity subgroups containing at least 100 participants each. Subgroups differences will be assessed using hierarchical Bayesian regression models with weakly informative priors. We will present the full posterior distributions of relative (risk ratios and ratios of means) and absolute differences (risk differences and mean differences) in each subgroup.

DISCUSSION

This study will provide data on the effects of heterogeneity in treatment intensity while accounting for patient characteristics in critically ill adult patients with septic shock.

REGISTRATIONS

The European Clinical Trials Database (EudraCT): 2018-000404-42, ClinicalTrials. gov: NCT03668236.

Single-Cell Spatial Transcriptomics Unveils Platelet-Fueled Cycling Macrophages for Kidney Fibrosis

With the increasing incidence of kidney diseases, there is an urgent need to develop therapeutic strategies to combat post-injury fibrosis. Immune cells, including platelets, play a pivotal role in this repair process, primarily through their released cytokines. However, the specific role of platelets in kidney injury and subsequent repair remains underexplored. Here, the detrimental role of platelets in renal recovery following ischemia/reperfusion injury and its contribution to acute kidney injury  to chronic kidney disease transition is aimed to investigated. In this study, it is shown that depleting platelets accelerates injury resolution and significantly reduces fibrosis. Employing advanced single-cell and spatial transcriptomic techniques, macrophages as the primary mediators modulated by platelet signals is identified. A novel subset of macrophages, termed "cycling M2", which exhibit an M2 phenotype combined with enhanced proliferative activity is uncovered. This subset emerges in the injured kidney during the resolution phase and is modulated by platelet-derived thrombospondin 1 (THBS1) signaling, acquiring profibrotic characteristics. Conversely, targeted inhibition of THBS1 markedly downregulates the cycling M2 macrophage, thereby mitigating fibrotic progression. Overall, this findings highlight the adverse role of platelet THBS1-boosted cycling M2 macrophages in renal injury repair and suggest platelet THBS1 as a promising therapeutic target for alleviating inflammation and kidney fibrosis.

Exposure to postoperative hypothermia and its association with complications after major abdominal surgery: a retrospective cohort study

Purpose

Many patients who undergo major abdominal surgery experience inadvertent hypothermia during the perioperative period. This study aimed to identify risk factors related to postoperative hypothermia and their association with postoperative complications.

Methods

This retrospective cohort study used data from Seoul National University Bundang Hospital, a tertiary university medical center in South Korea, between January 1, 2018 and December 31, 2022. We included patients aged ≥18 years who underwent elective major abdominal surgery for more than 2 hours in the operating room. The patients were categorized into the hypothermia (body temperature <36.5℃) and non-hypothermia (body temperature ≥36.5℃) groups.

Results

The study sample comprised 30,194 patients, and we classified 21,293 and 8,901 into the hypothermic and non-hypothermic groups, respectively. Some factors associated with the occurrence of postoperative hypothermia included the type of surgery. In the multivariable logistic regression model, the incidence of postoperative complications was 9% higher in the hypothermia group than in the non-hypothermic group (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.01-1.19; P = 0.040). Among postoperative complications, the hypothermic group showed a 14% higher incidence of acute kidney injury (OR, 1.14; 95% CI, 1.04-1.25; P = 0.007) than the non-hypothermic group.

Conclusion

The appearance of postoperative hypothermia during the first 30 minutes of the recovery period was significantly associated with the appearance of postoperative complications, especially acute kidney injury. However, further studies are required to validate these findings.

Layer-by-Layer Assembly of Renal-Targeted Polymeric Nanoparticles for Robust Arginase-2 Knockdown and Contrast-Induced Acute Kidney Injury Prevention

The mitochondrial enzyme arginase-2 (Arg-2) is implicated in the pathophysiology of contrast-induced acute kidney injury (CI-AKI). Therefore, Arg-2 represents a candid target for CI-AKI prevention. Here, layer-by-layer (LbL) assembled renal-targeting polymeric nanoparticles are developed to efficiently deliver small interfering RNA (siRNA), knockdown Arg-2 expression in renal tubules, and prevention of CI-AKI is evaluated. First, near-infrared dye-loaded poly(lactic-co-glycolic acid) (PLGA) anionic cores are electrostatically coated with cationic chitosan (CS) to facilitate the adsorption and stabilization of Arg-2 siRNA. Next, nanoparticles are coated with anionic hyaluronan (HA) to provide protection against siRNA leakage and shielding against early clearance. Sequential electrostatic layering of CS and HA improves loading capacity of Arg-2 siRNA and yields LbL-assembled nanoparticles. Renal targeting and accumulation is enhanced by modifying the outermost layer of HA with a kidney targeting peptide (HA-KTP). The resultant kidney-targeting and siRNA loaded nanoparticles (PLGA/CS/HA-KTP siRNA) exhibit proprietary accumulation in kidneys and proximal tubular cells at 24 h post-tail vein injection. In iohexol-induced in vitro and in vivo CI-AKI models, PLGA/CS/HA-KTP siRNA delivery alleviates oxidative and nitrification stress, and rescues mitochondrial dysfunction while reducing apoptosis, thereby demonstrating a robust and satisfactory therapeutic effect. Thus, PLGA/CS/HA-KTP siRNA nanoparticles offer a promising candidate therapy to protect against CI-AKI.

Association between Preoperative Blood Pressures and Postoperative Adverse Events

BACKGROUND

The relationship between postoperative adverse events and blood pressures in the preoperative period remains poorly understood. This study tested the hypothesis that day-of-surgery preoperative blood pressures are associated with postoperative adverse events.

METHODS

The authors conducted a retrospective, observational study of adult patients having elective procedures requiring an inpatient stay between November 2017 and July 2021 at Vanderbilt University Medical Center to examine the independent associations between preoperative systolic and diastolic blood pressures (SBP, DBP) recorded immediately before anesthesia care and number of postoperative adverse events-myocardial injury, stroke, acute kidney injury, and mortality-while adjusting for potential confounders. The study used multivariable ordinal logistic regression to model the relationship.

RESULTS

The analysis included 57,389 cases. The overall incidence of myocardial injury, stroke, acute kidney injury, and mortality within 30 days of surgery was 3.4% (1,967 events), 0.4% (223), 10.2% (5,871), and 2.1% (1,223), respectively. The independent associations between both SBP and DBP measurements and number of postoperative adverse events were found to be U-shaped, with greater risk both above and less than SBP 143 mmHg and DBP 86 mmHg-the troughs of the curves. The associations were strongest at SBP 173 mmHg (adjusted odds ratio, 1.212 vs. 143 mmHg; 95% CI, 1.021 to 1.439; P = 0.028), SBP 93 mmHg (adjusted odds ratio, 1.339 vs. 143 mmHg; 95% CI, 1.211 to 1.479; P < 0.001), DBP 106 mmHg (adjusted odds ratio, 1.294 vs. 86 mmHg; 95% CI, 1.003 to 1.17671; P = 0.048), and DBP 46 mmHg (adjusted odds ratio, 1.399 vs. 86 mmHg; 95% CI, 1.244 to 1.558; P < 0.001).

CONCLUSIONS

Preoperative blood pressures both less than and above a specific threshold were independently associated with a higher number of postoperative adverse events, but the data do not support specific strategies for managing patients with low or high blood pressure on the day of surgery.

EDITOR’S PERSPECTIVE

Characteristics and outcomes for general anesthesia in Denmark

BACKGROUND

General anesthesia is common, but concerns regarding post-operative complications and mortality remain. No study has described the Danish patient population undergoing general anesthesia on a national level. The aim of this study was to describe the characteristics and outcomes of patients undergoing general anesthesia in Denmark.

METHODS

This study was a registry-based observational cohort study of adult patients (≥18 years) undergoing general anesthesia in Denmark during 2020 and 2021. Data from nationwide registries covering patient characteristics, anesthesia and procedure information, and patient outcomes were combined. Descriptive statistics were used to present findings, both overall and in subgroups based on the American Society of Anesthesiologists (ASA) classification.

RESULTS

We identified 453,133 cases of general anesthesia in 328,951 unique patients. The median age was 57 years (quartiles: 41, 71), and 242,679 (54%) were females. Data on ASA classification were missing for less than 1% of the population, and ASA II was the most prevalent ASA classification (49%). Among cases of general anesthesia, 0.1% experienced a stroke, 0.2% had in-hospital cardiac arrest, and 3.9% had a stay in the intensive care unit within 30 days. Mortality at 30 days and 1 year were 1.8% and 6.3%, respectively, increasing with a higher ASA classification.

CONCLUSION

This study offers the first comprehensive overview of adult patients undergoing general anesthesia in Denmark. Post-anesthesia complications were few and increased with ASA classification.

Recognition patterns of acute kidney injury in hospitalized patients

Background

Acute kidney injury (AKI) during hospitalization is associated with increased complications and mortality. Despite efforts to standardize AKI management, its recognition in clinical practice is limited.

Methods

To assess and characterize different patterns of AKI diagnosis, we collected clinical data, serum creatinine (sCr) levels, comorbidities and outcomes from adult patients using the Hospital Discharge Form (HDF). AKI diagnosis was based on administrative data and according to Kidney Disease: Improving Global Outcomes (KDIGO) criteria by evaluating sCr variations during hospitalization. Additionally, patients were categorized based on the timing of AKI onset.

Results

Among 56 820 patients, 42 900 (75.5%) had no AKI, 1893 (3.3%) had AKI diagnosed by sCr changes and coded in the HDF (full-AKI), 2529 (4.4%) had AKI reported on the HDF but not meeting sCr-based criteria (HDF-AKI) and 9498 (16.7%) had undetected AKI diagnosed by sCr changes but not coded in the HDF (KDIGO-AKI). Overall, AKI incidence was 24.5%, with a 68% undetection rate. Patients with KDIGO-AKI were younger and had a higher proportion of females, lower comorbidity burden, milder AKI stages, more frequent admissions to surgical wards and lower mortality compared with full-AKI patients. All AKI groups had worse outcomes than those without AKI, and AKI, even if undetected, was independently associated with mortality risk. Patients with AKI at admission had different profiles and better outcomes than those developing AKI later.

Conclusions

AKI recognition in hospitalized patients is highly heterogeneous, with a significant prevalence of undetection. This variability may be affected by patients' characteristics, AKI-related factors, diagnostic approaches and in-hospital patient management. AKI remains a major risk factor, emphasizing the importance of ensuring proper diagnosis for all patients.

The medical treatment of cardiogenic shock

Cardiogenic shock is characterized by tissue hypoperfusion due to the inadequate cardiac output to maintain the tissue oxygen demand. Despite some advances in cardiogenic shock management, extremely high mortality is still associated with this clinical syndrome. Its management is based on the immediate stabilization of hemodynamic parameters through medical care and the use of mechanical circulatory supports in specialized centers. This review aims to understand the cardiogenic shock current medical treatment, consisting mainly of inotropic drugs, vasopressors and coronary revascularization. In addition, we highlight the relevance of applying measures to other organ levels based on the optimization of mechanical ventilation and the appropriate initiation of renal replacement therapy.

Diagnosis of acute myocardial infarction in patients with renal failure using high-sensitivity cardiac troponin T

AIMS

Diagnosing myocardial infarction (MI) in patients with chronic kidney disease (CKD) is difficult as they often have increased high-sensitivity cardiac troponin T (hs-cTnT) concentrations.

METHODS AND RESULTS

Observational US cohort study of emergency department patients undergoing hs-cTnT measurement. Cases with ≥1 hs-cTnT increase > 99th percentile were adjudicated following the Fourth Universal Definition of MI. Diagnostic performance of baseline and serial 2 h hs-cTnT thresholds for ruling-in acute MI was compared between those without and with CKD (estimated glomerular filtration rate < 60 mL/min/1.73 m2). The study cohort included 1992 patients, amongst whom 501 (25%) had CKD. There were 75 (15%) and 350 (70%) patients with CKD and 80 (5%) and 351 (24%) without CKD who had acute MI and myocardial injury. In CKD patients with baseline hs-cTnT thresholds of ≥52, >100, >200, or >300 ng/L, positive predictive values (PPVs) for MI were 36% (95% CI 28-45), 53% (95% CI 39-67), 73% (95% CI 50-89), and 80% (95% CI 44-98), and in those without CKD, 61% (95% CI 47-73), 69% (95% CI 49-85), 59% (95% CI 33-82), and 54% (95% CI 25-81). In CKD patients with a 2 h hs-cTnT delta of ≥10, >20, or >30 ng/L, PPVs were 66% (95% CI 51-79), 86% (95% CI 68-96), and 88% (95% CI 68-97), and in those without CKD, 64% (95% CI 50-76), 73% (95% CI 57-86), and 75% (95% CI 58-88).

CONCLUSION

Diagnostic performance of standard baseline and serial 2 h hs-cTnT thresholds to rule-in MI is suboptimal in CKD patients. It significantly improves when using higher baseline thresholds and delta values.

Association of Age, Frailty, and Strategy for Initiation of Renal-Replacement Therapy: A Post Hoc analysis of the STARRT-Acute Kidney Injury Trial

INTRODUCTION

This study was designed to assess the association of age and frailty with clinical outcomes in patients with severe acute kidney injury (AKI), according to accelerated and standard renal-replacement therapy (RRT) initiation strategies in the STARRT-AKI trial.

METHODS

This was a secondary analysis of an international randomized trial. Older age was defined as ≥65 years. Frailty was assessed using the clinical frailty scale (CFS) score and defined as a score ≥5. The primary outcome was all-cause mortality at 90 days. Secondary outcomes included RRT dependence and RRT-free days at 90 days. We used logistic and linear regression and interaction testing to explore the impact of age and frailty on clinical outcomes.

RESULTS

Of 2,927 patients randomized in the STARRT-AKI trial, 1,616 (55.2%) were aged ≥65 years (median [interquartile range] 73.9 [69.4-78.9]). Older patients had greater comorbid cardiovascular and chronic kidney disease, were more likely to be surgical admissions and to receive vasopressors at baseline. Older patients had higher 90-day mortality (50.4% vs. 35.6%, adjusted-odds ratio (OR), 1.81 [1.53-2.13], p < 0.001). There was no significant difference in RRT dependence at 90 days between older and younger patients (8.7% vs. 7.8%, adjusted-OR, 1.21 [0.82-1.79], p = 0.325). Patients with frailty had higher mortality; but no difference in RRT dependence at 90 days. There was no significant interaction between age and CFS score in relation to mortality, RRT dependence at 90 days, and other secondary outcomes. There was no significant difference in the proportion of patients who received RRT in the standard-strategy stratified by age groups (adjusted-OR, 0.85 [0.67-1.08], p = 0.180).

CONCLUSION

In this secondary analysis of the STARRT-AKI trial, older and frail patients had higher mortality at 90 days; however, there was no difference in RRT dependence. Mortality and RRT dependence were not modified by RRT initiation strategy in older or frail patients.