Cardiac Surgery-associated Acute Kidney Injury Research Articles

Acute Kidney Injury after Cardiac Surgery.

Cardiac surgery-associated acute kidney injury (CS-AKI) remains a vexing issue. Clinical trials for the prevention of CS-AKI have been disappointing despite enormous initial enthusiasm based on experimental data. The schism in experimental and clinical data has triggered a relook at our understanding of CS-AKI and the experimental and preclinical models. In this review, we discuss the therapeutic targets of major clinical trials. The silver lining in the midst is the standardization of anesthetic and perioperative care proposed by national societies. Implementation of the KDIGO bundle is a reasonable option to decrease the incidence of CS-AKI despite lack of proven robust benefits.

Urine metabolite changes after cardiac surgery predict acute kidney injury.

Acute kidney injury (AKI) is a serious complication in patients undergoing cardiac surgery, with the underlying mechanism remaining elusive and a lack of specific biomarkers for cardiac surgery-associated AKI (CS-AKI). We performed an untargeted metabolomics analysis of urine samples procured from a cohort of patients with or without AKI at 6 and 24 h following cardiac surgery. Based on the differential urinary metabolites discovered, we further examined the expressions of the key metabolic enzymes that regulate these metabolites in kidney during AKI using a mouse model of ischemia-reperfusion injury (IRI) and in hypoxia-treated tubular epithelial cells (TECs). The urine metabolomic profiles in AKI patients were significantly different from those in non-AKI patients, including upregulation of tryptophan metabolism- and aerobic glycolysis-related metabolites, such as l-tryptophan and d-glucose-1-phosphate, and downregulation of fatty acid oxidation (FAO) and tricarboxylic acid (TCA) cycle-related metabolites. Spearman correlation analysis showed that serum creatinine was positively correlated with urinary l-tryptophan and indole, which had high accuracy for predicting AKI. In animal experiments, we demonstrated that the expression of rate-limiting enzymes in glycolysis, such as hexokinase II (HK2), was significantly upregulated during renal IRI. However, the TCA cycle-related key enzyme citrate synthase was significantly downregulated after IRI. In vitro, hypoxia induced downregulation of citrate synthase in TECs. In addition, FAO-related gene peroxisome proliferator-activated receptor alpha (PPARα) was remarkably downregulated in kidney during renal IRI. This study presents urinary metabolites related to CS-AKI, indicating the rewiring of the metabolism in kidney during AKI, identifying potential AKI biomarkers.

Carboxyhemoglobin as Potential Biomarker for Cardiac Surgery Associated Acute Kidney Injury

Carboxyhemoglobin (CO-Hb) is a marker of hemolysis and inflammation, both risk factors for cardiac surgery-associated AKI (CSA-AKI). However, the association between CO-Hb and CSA-AKI remains unknown. A retrospective cohort study. Tertiary university-affiliated metropolitan hospital: single center. Adult on-pump cardiac surgery patients from July 2014 to June 2022 (N = 1,698). None. Patients were stratified into quartiles based on CO-Hb levels at intensive care unit (ICU) admission. A progressive increased risk of CSA-AKI was observed with higher CO-Hb levels at ICU admission. On multivariable logistic regression analysis, the highest quartile (CO-Hb ≥ 1.4%) showed an independent association with the occurrence of CSA-AKI (odds ratio 1.45 compared to the lowest quartile [CO-Hb < 1.0%], 95% CI 1.023-2.071; p = 0.038). Compared to patients with CO-Hb <1.4%, patients with CO-Hb ≥ 1.4% at ICU admission had significantly higher postoperative creatinine (135 vs 116 μmol/L, p < 0.001), higher rates of postoperative RRT (6.7% vs 2.3%, p < 0.001) and AKI (p < 0.001) on univariable analysis and shorter time to event for AKI or death (p < 0.001). CO-Hb ≥ 1.4% at ICU admission is an independent risk factor for CSA-AKI, which is easily obtainable and available on routine arterial blood gas measurements. Thus, CO-Hb may serve as a practical and biologically logical biomarker for risk stratification and population enrichment in trials of CSA-AKI prevention.

Predictors of Renal Replacement Therapy in Cardiac Surgery-Associated Acute Kidney Injury Patients: A Single-Centered, Retrospective Study

Abstract Background: Studies have reported that cardiac surgery-associated acute kidney injury (CSA-AKI) patients requiring dialysis or renal replacement therapy (RRT) have a higher risk of in-hospital mortality. This study aimed to investigate the predictors contributing to postoperative RRT. Materials and Methods: This retrospective observational study was conducted at a single cardiovascular center. Patients who underwent cardiac surgery complicated with CSA-AKI in the intensive care unit (ICU) from January 2020 to December 2022 were included. They were categorized into two groups: those who required RRT (group A, n = 302) and those who did not (group B, n = 811). Bivariable and multivariable analyzes were conducted to compare the risk with odds ratio (OR) for in-hospital mortality between those groups. Results: We analyzed 1113 patients (29.4%) in the final analysis. The in-hospital mortality rate was 31.8% vs. 4.2% (OR = 10.6, P &lt; 0.001). Variables that significantly predicted postoperative RRT requirements in CSA-AKI patients included female sex (P = 0.038), coronary artery bypass graft (P = 0.001), multiple valves surgery (P = 0.032), diabetes (P = 0.01), renal disease (P = 0.005), postoperative serum creatinine &gt;3.0 mg/dL (P &lt; 0.001), mechanical ventilation use of ≥48 h (P &lt; 0.001), ICU length of stay of &gt;5 days (P &lt; 0.001), use of more than two inotropes and vasoactive agents, (P &lt; 0.001), and postoperative intra-aortic balloon pump (IABP) (P &lt; 0.001). Conclusion: CSA-AKI patients who require dialysis are associated with a higher mortality. Predictors of postoperative RRT included female sex, certain types of surgery, diabetes, postoperative serum creatinine &gt;3.0 mg/dL, mechanical ventilation use of ≥48 h, ICU length of stay of &gt;5 days, use of more than two inotropes and vasoactive agents, and postoperative IABP.

Risk factors for progression to chronic kidney disease in patients with cardiac valve replacement surgery-associated acute kidney injury

Objective: To explore the risk factors for progression to chronic kidney disease (CKD) in patients with cardiac valve replacement surgery-associated acute kidney injury (AKI). Methods: A retrospective, nested case-control study was conducted at Fuwai Central China Cardiovascular Hospital. The study subjects were patients who underwent cardiac valve replacement surgery from January 1, 2018 to December 31, 2020, with a baseline estimated glomerular filtration rate (eGFR)>60 ml·min-1·(1.73 m2)-1 and postoperative complication of AKI. The patients were followed up for 90 days after discharge from hospital. The endpoint event was defined as progression to CKD 90 days after the occurrence of cardiac valve replacement surgery-associated AKI. The patients were divided into CKD group and non-CKD group based on whether they experienced endpoint event. The baseline clinical data were compared between the two groups. The measurement data with non-normal distribution was represented as M (Q1,Q3). Logistic regression model was used to analyze the risk factors of endpoint event. The receiver-operating characteristic (ROC) curve was drawn to evaluate the performance for predicting CKD in cardiac valve replacement surgery-associated AKI patients. Results: A total of 149 cardiac valve replacement surgery-associated AKI patients (86 males and 63 females) were included in the study, aged (59.0±10.2) years. There were 27 patients (18.1%) who progressed to new-onset CKD 90 days after the occurrence of cardiac valve replacement surgery-associated AKI. Compared with non-CKD group, patients in CKD group had older age [66 (58, 70) vs 59 (53, 64) years], lower baseline eGFR [76.3 (65.8, 98.5) vs 92.7 (78.5, 101.6) ml·min-1·(1.73 m2)-1], higher proportion of preoperative hypertension [51.9% (14/27) vs 27.9% (34/122)] and serum creatinine at discharge [136 (101, 165) vs 86 (65, 104) μmol/L], and the differences were statistically significant (all P<0.05). The multivariate logistic regression analysis results revealed that older age (OR=1.063, 95%CI: 1.001-1.129, P=0.047), preoperative hypertension (OR=3.070, 95%CI: 1.105-8.532, P=0.031) and higher serum creatinine at discharge (OR=1.026, 95%CI:1.013-1.038, P<0.001) were risk factors for progression to CKD in patients with cardiac valve replacement surgery-associated AKI. The clinical risk model including age, preoperative hypertension, preoperative baseline eGFR, and serum creatinine at discharge produced a moderate performance for predicting progression to CKD in patients with cardiac valve replacement surgery-associated AKI [the area under the curve (AUC)=0.865, 95%CI: 0.790-0.940, P<0.001]. Conclusion: Older age, preoperative hypertension and higher serum creatinine at discharge are risk factors for progression to CKD in patients with cardiac valve replacement surgery-associated AKI.

Benzylic rearrangement for urinary analysis of guanidino and ureido compounds in cardiac surgery-associated acute kidney injury using high-performance liquid chromatography-tandem mass spectrometry.

RationaleBecause acute kidney injury (AKI) is closely related to poor prognosis in critically ill patients, developing biomarkers for its prediction and early diagnosis is particularly important. Endogenous guanidino compounds (GCs) and ureido compounds (UCs) can participate in various biochemical processes because of their important physiological activities. The aim of this study was to investigate the alteration profiles of urinary GCs/UCs as potential biomarkers in patients with cardiac surgery–associated acute kidney injury (CSA‐AKI) at different stages.MethodsGCs/UCs were reacted with benzil via benzylic rearrangement, and their derivatives were used to investigate fragmentation mechanisms using tandem mass spectrometry (MS/MS) in positive ion mode. Furthermore, a high‐performance liquid chromatography (HPLC)–MS/MS method was developed to measure the concentrations of GCs/UCs in urine samples taken from patients with CSA‐AKI at different time points.ResultsMS/MS analysis in positive ion mode showed that benzylic GCs/UCs exhibited similar fragmentation processes, which could produce the characteristic ion (C13H12N+) at m/z 182.0. Furthermore, an obviously different fragmentation pattern of benzylic UCs in the positive ion mode might be due to the neutral loss of the H2CO2 group under low collision energy. Of the eight selected GCs/UCs, methylguanidine exhibited significantly increased concentrations in urine when CSA‐AKI occurred, whereas guanidinoethyl sulfonate (GDS), homoarginine (HArg) and homocitrulline (HCit) exhibited decreased concentrations. After recovery from AKI, the urinary concentrations of the aforementioned GCs/UCs returned to normal. Some of the aforementioned metabolites with significant changes (GDS, HArg and HCit) had large areas under the curve in the receiver operating characteristic curve for distinguishing AKI stages on the third day after surgery.ConclusionsIn patients with CSA‐AKI, urinary GCs/UCs were significantly disrupted due to injured kidney, and some GC/UC metabolites exhibited a good ability to become potential biomarkers for AKI stages. The present study provides essential resources and new therapeutic targets for further research on CSA‐AKI.

A Case of Cardiac Surgery-Associated Acute Kidney Injury

Approximately 2 million patients undergo cardiac surgery annually with 20% to 30% developing the cardiac surgery-associated acute kidney injury. Patient who has undergone cardiac surgery in the past week and meets the criteria for acute kidney injury can be classified as a cardiac surgery-associated acute kidney injury. The cardiac surgery-associated acute kidney injury may be caused by various factors during perioperative period. Preoperative risk factors include advanced age, female gender, pre-existing renal insufficiency, heart failure, left main coronary artery disease, diabetes, chronic obstructive pulmonary disease, peripheral vascular disease, liver disease, low cardiac output and hypotension. Intraoperative risk factors include the type of surgery (valve surgery, combined valve and coronary artery surgery, emergency and reoperations), low-flow cardiopulmonary bypass, hypothermic cardiopulmonary bypass, deep hypothermic circulatory arrest, cardiopulmonary bypass duration &amp;gt;100-120 minutes, hemodilution, hemolysis and hemoglobinuria due to prolonged cardiopulmonary bypass duration. We present the case of a 53-year-old female with severe valvular heart disease complicated by infecting human immunodeficiency virus. She experienced an acute kidney injury after cardiac surgery. The rationale for this case report is to learn about the risk factors of cardiac surgery-associated acute kidney injury and take measures to prevent it.

The Relationship Between Perioperative Blood Product Use and the Incidence of Postoperative Renal Injury in Infants Undergoing Cardiac Surgery

Cardiac Surgery Associated Acute Kidney Injury (CS-AKI) is a serious complication that occurs in patients following cardiac surgery. It is characterized by the rapid decline in kidney function, leading to potential long-term kidney damage or even kidney failure. CS-AKI is a significant health concern, as it not only prolongs hospital stays and recovery time but also increases the risk of mortality. This study, conducted as a prospective observational study, aimed to investigate the relationship between perioperative blood product use and the incidence of postoperative acute kidney injury (AKI) in infants and young children undergoing cardiac surgery. It examined the perioperative use of these blood products and its association with the occurrence of AKI. The findings of this study revealed a significant association between the use of red blood cell suspension and platelets and the development of postoperative AKI. This suggests that the administration of these blood products during cardiac surgery may increase the risk of kidney injury in infants and young children. However, it is important to note that the study did not find a statistically significant association between plasma transfusion volume and the incidence of AKI. This suggests that while the use of certain blood products may contribute to the risk of AKI, the volume of plasma transfused does not seem to have a significant impact. The findings of this study provide valuable insights into the perioperative management of infants and young children undergoing cardiac surgery. It underscores the importance of carefully considering the use of blood products during surgery and taking necessary measures to minimize the risk of AKI.

Evaluating the Prevalence of Cardiac Surgery–associated Acute Kidney Injury After Septal Myectomy Combined With Concomitant Procedures in Obstructive Hypertrophic Cardiomyopathy

ObjectivesHypertrophic obstructive cardiomyopathy (HOCM) may be treated by septal myectomy. Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication, but little is known about its incidence after septal myectomy. The objectives were to (i) evaluate the prevalence of CSA-AKI after septal myectomy and (ii) identify potential perioperative and phenotype-related factors contributing to CSA-AKI. DesignRetrospective database analysis with new data analysis. SettingSingle expertise university academic centre for septal myectomy HOCM patients. ParticipantData from 238 HOCM patients operated with septal myectomy between 2005-2022. InterventionsCSA-AKI was stratified by the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines by measurement of creatinine and urine production. Important HOCM phenotype-related and perioperative factors were analysed for their possible association with CSA-AKI. Measurements and Main ResultsCSA-AKI occurred in 45% of patients, of these, 55% were classified as KDIGO stage I, and the remaining 45% as stage II, with no chronic kidney damage being observed. Moreover, there were no phenotypical or perioperative characteristics that were more prevalent in the CSA-AKI cohort. However, the use of beta-blockers and coronary artery disease were more prevalent in the CSA-AKI cohort. ConclusionsCSA-AKI is a common complication after septal myectomy, but was transient and kidney function recovered in all patients.

Mechanism and clinical role of TIMP-2 and IGFBP-7 in cardiac surgery-associated acute kidney injury: A review.

Acute kidney injury (AKI) is a common postoperative complication, but there is still a lack of accurate biomarkers. Cardiac surgery-associated AKI is the most common cause of major-surgery-related AKI, and patients requiring renal replacement therapy have high mortality rates. Early diagnosis, intervention, and management are crucial for improving patient prognosis. However, diagnosing AKI based solely on changes in serum creatinine level and urine output is insufficient, as these changes often lag behind actual kidney damage, making early detection challenging. Biomarkers such as tissue inhibitor of metalloproteinases-2 (TIMP-2) and insulin-like growth factor-binding protein-7 (IGFBP-7) have been found to be significant predictors of moderate-to-severe AKI when combined with urine content analysis. This article reviews the mechanism of biomarkers TIMP-2 and IGFBP-7 in AKI and provides a comprehensive overview of the clinical effects of TIMP-2 and IGFBP-7 in cardiac surgery-associated AKI, including prediction, diagnosis, and progression.

#2593 Comparison of four predictive scoring models as assessment tools for cardiac surgery-associated acute kidney injury in post cardiac surgery patients

Abstract Background and Aims Cardiac surgery-associated acute kidney injury (CSA-AKI) is a predominant contributor to hospital-acquired AKI in ICU following sepsis. Despite a rising frequency of CSA-AKI, currently examined predictive models have not consistently delivered accurate stratification. Utilizing risk stratification systems offers clinicians the opportunity to identify patients at high risk, extend monitoring intervals, facilitate timely referral to nephrology services, and promptly initiate effective preventive and therapeutic interventions known to enhance renal function. This study seeks to identify the most effective model by comparing four established predictive scoring systems. The objective of this single-center retrospective, cross sectional study is to compare the clinical values of the Cleveland Clinical Score, Mehta Score, Simplified Renal Index and Acute Kidney Injury following Cardiac Surgery (AKICS) Score in predicting CS-AKI among patients who underwent cardiac surgery. Method A comprehensive examination of medical records was conducted for all individuals who underwent open-heart surgery between January 2010 and January 2019. Those patients who had CSA-AKI were subsequently identified. These identified individuals underwent assessment using the four predictive scoring models, leading to their categorization into high or low-risk groups for AKI development. Binary logistics regression was then used to describe the association between CSA-AKI development and the four scoring methods as predictors. Results Among the 114 cases of open-heart surgeries, 86 were eligible for inclusion in the study. Half of the patients, specifically 43 individuals (50%), developed CS-AKI, with 5 requiring renal replacement therapy. Among the four scoring methods evaluated, only the Mehta score (95% CI, p 0.019) and AKICS score (95% CI, p 0.011) demonstrated statistical significance in predicting CS-AKI. The odds ratios for both the Mehta Score (1.10) and AKICS Score (1.19) exceeded 1, suggesting that an increase in either score is associated with a higher likelihood of AKI occurrence. Conversely, the Cleveland Clinical Score (p 0.106) and Simplified Renal Index (p 0.399) were not found to be predictive. Conclusion In this single-center study, both the Mehta score and the AKICS scoring system demonstrated predictability for AKI after open-heart surgery. However, the Cleveland Clinical Scoring and Simplified Renal Index did not exhibit predictive capability in this context.

#624 The impact of hemoadsorption in patients with borderline chronic kidney disease undergoing coronary artery bypass grafting

Abstract Background and Aims With an annual incidence of up to 30%, cardiac surgery–associated acute kidney injury (CSA-AKI) may be one of the most underappreciated yet frequent complications and renal protective adjustments are crucial. We evaluated the impact of hemoadsorption as adjunctive therapy on clinical outcome in Kidney Disease Improving Global Outcomes (KDIGO) G2/A2) patients undergoing coronary artery bypass grafting (CABG). Method During a three-year period, 40 patients undergoing CABG with borderline chronic kidney disease (KDIGO-G2/A2) were treated with adjunctive hemoadsorption therapy and were compared by propensity score-matched 40 patients (KDIGO G2/A2) (Control). Primary endpoints were the need for renal replacement therapy (RRT)/dialysis and/or worsening of KDIGO stage in the perioperative period. Secondary endpoints were the change in inflammatory biomarkers, vasopressor requirement and ICU/hospital stay. In the study group, a 300 mL hemoadsorber (Cytosorbents Inc, NJ) was used for the entire duration of cardiopulmonary bypass (CPB). All patients were prepared via enhanced recovery after surgery (ERAS) protocol and surgical procedures were performed under moderate hypothermia with pulsatile flow and ultrafiltration. Patients with septic shock, limited life expectancy and refused to give consent were excluded. Results After institutional ethics committee approval was obtained, written informed consent was received from each patient. No significant difference was noted between groups in demographic, operative data and preoperative baseline laboratory. At the end of CPB; s-Creatinine (mg/dL) (1.85 ± 0.6 vs 2.751 ± 0.6; p = 0.035), NT-proBNP (pg/L) (130 ± 30 vs 180 ± 40; p = 0.04), IL-6 (pg/mL) (8.2 ± 4 vs 22.2 ± 4; p = 0.012) and myoglobulin (pg/L) (210 ± 75 vs 310 ± 80; p = 0.04) levels were significantly lower in the study group versus control. Clinical outcome is summarized in Figure. Conclusion This pioneering study demonstrated the additional protective effects of hemoadsorption in patients with borderline chronic kidney disease (KDIGO-G2/A2) undergoing CABG. Elimination of inflammatory parameters might be a complementary mechanism resulting in lesser worsening of kidney function/need of RRT and ICU stay. These findings require validation in large, multicenter trials.

#976 Empagliflozin limits AKI incidence and severity following cardiac surgery: an open-label phase IV randomized pilot study

Abstract Background and Aims Cardiac surgery-associated acute kidney injury (CSA-AKI) is a frequent complication of cardiac surgery assisted by cardiopulmonary bypass (CPB). Currently, no effective preventative strategies exist to reduce the incidence of acute kidney injury (AKI). Sodium-glucose transport protein 2 (SGLT2) inhibitors are effective in reducing the incidence of AKI in studies conducted in patients with chronic kidney disease. Therefore, we hypothesized that perioperative SGLT2 inhibition could reduce the incidence of CSA-AKI. Method In this open-label phase IV, randomized, parallel-group, balanced (1:1), pilot study, adult patients undergoing elective cardiac surgery with CPB were randomized to receive 10 mg empagliflozin per os once daily three days before surgery until two days after surgery, or standard care. The primary outcome was AKI incidence according to the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Other outcomes included hypoxia-inducible factor 1 alpha (HIF1A) and urinary Kidney Injury Molecule (KIM-1), urinary neutrophil gelatinase associated lipocalin (NGAL) and metabolic parameters such as plasma ketone and glucose concentrations. Results Between March 2022 and April 2023, 60 patients were randomized to empagliflozin (n = 29) or control (n = 31). All patients who underwent cardiac surgery with CPB were included in the intention-to-treat analysis (n = 25; empagliflozin group, n = 30; control group). SGLT2 inhibition significantly reduced the incidence of all stages of AKI (20% vs 66.7%; absolute difference 46%, 95% CI .13 to .63, P &amp;lt; .001). This decline in AKI incidence was reflected in the kidney biomarkers. SGLT2 inhibition also significantly reduced the number of patients with postoperative hyperglycemia (28% vs 60%; absolute difference 32%, 95% CI −56.8 to −7.2, P = .029). We observed no differences in the incidence of neither ketoacidosis nor hypoglycemic events. Conclusion Perioperative SGLT2 inhibition, compared with standard of care, demonstrated a significant reduction in AKI incidence rates. These findings merit validation in a larger placebo-controlled trial which is currently ongoing. Supplementary figures:

Sex bias in prediction and diagnosis of cardiac surgery associated acute kidney injury

BackgroundFemale sex has been recognized as a risk factor for cardiac surgery associated acute kidney injury (CS-AKI). The current study sought to evaluate whether female sex is a risk factor for CS-AKI, or modifies the association of peri-operative change in serum creatinine with CS-AKI.MethodsObservational study of adult patients undergoing cardiac surgery between 2000 and 2019 in a single U.S. center. The main variable of interest was registered patient sex, identified from electronic medical records. The main outcome was CS-AKI within 2 weeks of surgery.ResultsOf 58526 patients, 19353 (33%) were female; 12934 (22%) incurred AKI based on ≥ 0.3 mg/dL or ≥ 50% rise in serum creatinine (any AKI), 3320 (5.7%) had moderate to severe AKI, and 1018 (1.7%) required dialysis within 2 weeks of surgery. Female sex was associated with higher risk for AKI in models that were based on preoperative serum creatinine (OR, 1.35; 95% CI, 1.29–1.42), and lower risk with the use of estimated glomerular filtration, (OR, 0.90; 95% CI, 0.86–0.95). The risk for moderate to severe CS-AKI for a given immediate peri-operative change in serum creatinine was higher in female compared to male patients (p < .0001 and p < .0001 for non-linearity), and the association was modified by pre-operative kidney function (p < .0001 for interaction).ConclusionsThe association of patient sex with CS-AKI and its direction was dependent on the operational definition of pre-operative kidney function, and differential outcome misclassification due to AKI defined by absolute change in serum creatinine.

Cardiac Surgery-Associated Acute Kidney Injury in Children after Cardiopulmonary Bypass

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a complication of cardiopulmonary bypass surgery that frequently occurs in children. The increased availability of pediatric cardiac surgery leads to yearly increases in congenital heart disease (CHD) procedures performed worldwide. The number of complications, including pediatric CSA-AKI, has also increased. Children with CSA-AKI have worse postoperative periods and require more complex post-op intensive care. Thus, the timely commencement of interventions to prevent and to treat kidney injury in CHD children are one of a leading goals of pediatric cardiac intensive care.

La dexmedetomidina mitiga la insuficiencia renal aguda tras la cirugía de revascularización coronaria: un ensayo clínico prospectivo

Introduction and objectivesTo evaluate the impact of dexmedetomidine impact on cardiac surgery-associated acute kidney injury (CSA-AKI), kidney function, and metabolic and oxidative stress in patients undergoing coronary artery bypass grafting with heart-lung machine support. MethodsA randomized double-masked trial with 238 participants (50-75 years) undergoing coronary artery bypass grafting was conducted from January 2021 to December 2022. The participants were divided into Dex (n=119) and NS (n = 119) groups. Dex was administered at 0.5 mcg/kg over 10minutes, then 0.4 mcg/kg/h until the end of surgery; the NS group received equivalent saline. Blood and urine were sampled at various time points pre- and postsurgery. The primary outcome measure was the incidence of CSA-AKI, defined as the occurrence of AKI within 96hours after surgery. ResultsThe incidence of CSA-AKI was significantly lower in the Dex group than in the NS group (18.26% vs 32.46%; P=.014). Substantial increases were found in estimated glomerular filtration rate value at T4–T6 (P<.05) and urine volume 24hours after surgery (P<.01). Marked decreases were found in serum creatinine level, blood glucose level at T1–T2 (P<.01), blood urea nitrogen level at T3–T6 (P<.01), free fatty acid level at T2–T3 (P<.01), and lactate level at T3–T4 (P<.01). ConclusionsDex reduces CSA-AKI, potentially by regulating metabolic disorders and reducing oxidative stress.Registered with the Chinese Clinical Study Registry (No. ChiCTR2100051804).

The Preventive Role of Glutamine Supplementation in Cardiac Surgery-Associated Kidney Injury from Experimental Research to Clinical Practice: A Narrative Review.

Acute kidney injury represents a significant threat in cardiac surgery regarding complications and costs. Novel preventive approaches are needed, as the therapeutic modalities are still limited. As experimental studies have demonstrated, glutamine, a conditionally essential amino acid, might have a protective role in this setting. Moreover, the levels of glutamine after the cardiopulmonary bypass are significantly lower. In clinical practice, various trials have investigated the effects of glutamine supplementation on cardiac surgery with encouraging results. However, these studies are heterogeneous regarding the selection criteria, timing, dose, outcomes studied, and way of glutamine administration. This narrative review aims to present the potential role of glutamine in cardiac surgery-associated acute kidney injury prevention, starting from the experimental studies and guidelines to the clinical practice and future directions.

Cystatin c as an early marker of cardiac surgery associated-acute kidney injury in children in Nigeria

Cystatin c as an early marker of cardiac surgery associated-acute kidney injury in children in Nigeria

Cardiac Surgery-Associated Acute Kidney Injury.

AKI is a common and serious complication of cardiac surgery that has a significant impact on patient morbidity and mortality. The Kidney Disease Improving Global Outcomes definition of AKI is widely used to classify and identify AKI associated with cardiac surgery (cardiac surgery-associated AKI [CSA-AKI]) on the basis of changes in serum creatinine and/or urine output. There are various preoperative, intraoperative, and postoperative risk factors for the development of CSA-AKI which should be recognized and addressed as early as possible to expedite its diagnosis, reduce its occurrence, and prevent or ameliorate its devastating complications. Crucial issues are the inaccuracy of serum creatinine as a surrogate parameter of kidney function in the perioperative setting of cardiothoracic surgery and the necessity to discover more representative markers of the pathophysiology of AKI. However, except for the tissue inhibitor of metalloproteinase-2 and insulin-like growth factor binding protein 7 ratio, other diagnostic biomarkers with an acceptable sensitivity and specificity are still lacking. This article provides a comprehensive review of various aspects of CSA-AKI, including pathogenesis, risk factors, diagnosis, biomarkers, classification, prevention, and treatment management.

Acute Dapagliflozin Administration Ameliorates Cardiac Surgery-Associated Acute Kidney Injury in a Rabbit Model.

Several studies have shown that sodium-glucose cotransporter-2 inhibitors have a renoprotective effect on acute kidney injury (AKI), but their effect on cardiac surgery-associated AKI is unknown. AKI was induced in 25 rabbits without diabetes mellitus by cardiopulmonary bypass (CPB) for 2 h and they were divided into 5 groups: sham; dapagliflozin-treated sham; CPB; dapagliflozin-treated CPB; and furosemide-treated CPB (n=5 in each group). Dapagliflozin was administered via the femoral vein before initiating CPB. Kidney tissue and urine and blood samples were collected after the surgical procedure. There were no differences in the hemodynamic variables of each group. Dapagliflozin reduced serum creatinine and blood urea nitrogen concentrations, and increased overall urine output (all P<0.05). Hematoxylin and eosin staining showed that the tubular injury score was improved after dapagliflozin administration (P<0.01). Dapagliflozin administration mitigated reactive oxygen species and kidney injury molecule-1 as assessed by immunohistochemistry (both P<0.0001). Protein expression analysis showed improvement of inflammatory cytokines and apoptosis, and antioxidant enzyme expression was elevated (all P<0.05) through activation of the nuclear factor erythroid 2-related factor 2 pathway (P<0.01) by dapagliflozin. Acute intravenous administration of dapagliflozin protects against CPB-induced AKI. Dapagliflozin may have direct renoprotective effects in renal tubular cells.