Cardiac Surgery-associated Acute Kidney Research Articles

Hemolysis Index, Carboxyhemoglobin, and Methemoglobin for the Early Identification of Patients at Risk for Cardiac Surgery–Associated Acute Kidney Injury

Hemolysis is a contributor to CS-AKI. Biochemistry analyzers provide a hemolysis index to quantify in vitro hemolysis, a condition that can, for example, affect the accuracy of potassium concentration measurements. We aimed to assess whether the postoperative plasma level of the hemolysis index (HIpostoperative) could aid the early recognition of patients at risk for cardiac surgery-associated acute kidney injury (CS-AKI) and also to evaluate other hemolysis indicators: plasma carboxyhemoglobin (COHbpostoperative) and methemoglobin (MetHbpostoperative). One-year retrospective study. University hospital. Patients undergoing elective cardiac surgery. None. In 1090 patients, the median HIpostoperative was higher in patients who developed CS-AKI compared to patients who did not (11 mg/dL [interquartile range (IQR), 5-38 mg/dL] v 7 mg/dL [IQR, 3-16 mg/dL]; p < 0.001). HIpostoperative refined the early recognition of CS-AKI: the area under the precision-recall curve (AUPRC) for HIpostoperative was 37% (95% confidence interval [CI], 31%-42%), whereas the AUPRC associated with no discriminative power, equal to the prevalence of CS-AKI in the whole population, was 21%. Among the 611 patients with measurements for all 3 biomarkers, the AUPRC of HIpostoperative was higher than that of COHbpostoperative or MetHbpostoperative (+6.6% and +7.4% respectively; p < 0.0001 for both). Unlike COHbpostoperative or MetHbpostoperative, the incorporation of HIpostoperative into a model (trained on a sample then validated in another sample) of CS-AKI early recognition significantly enhanced its performance, with a +1.9% (95% CI, 1.6%-2.1%) increase in AUPRC (p < 0.0001). Elevated HIpostoperative represents an early alert signal for the development of CS-AKI. Our findings support the incorporation of HIpostoperative, a readily available biomarker, into predictive scores of CS-AKI.

Cardiac surgery associated acute kidney injury, incidence, and predictors. Prospective observational single center study.

Acute kidney injury (AKI) is a condition characterized by a sudden decline in kidney function, leading to accumulation of waste products and fluids in the body. It is a common and serious complication in patients with cardiovascular diseases, and it is associated with increased morbidity and mortality.&lt;br /&gt; &lt;br /&gt; &lt;b&gt;Aim&lt;/b&gt;&lt;br /&gt; In this study, we explore the relationship between cardiac issues and the development of AKI, as well as strategies for its prevention and management. The primary aim of this study is to examine the incidence and risk factors for the AKI in patients admitted to the cardiac intensive care unit/CICU), as well as the impact of AKI on patient outcomes.&lt;br /&gt; &lt;b&gt;&amp;nbsp;&lt;/b&gt;&lt;br /&gt; &lt;b&gt;Methods&lt;/b&gt;&lt;br /&gt; We conducted prospective observational single center study. 292 consecutive patients admitted to ICU after open heart surgery by sternotomy were included. Patients were monitored in ICU for frequency of AKI, perioperative risk factors, cardiac surgery-associated acute kidney injury (CSA-AKI) and their impact on patients’ outcome.&lt;br /&gt; &lt;b&gt;Results&lt;/b&gt;&lt;br /&gt; After admission to the intensive care unit, 33 patients (11.3%) developed CSA-AKI in the postoperative period. According to the analysis, male gender (p=0.03), decreased GFR (p=0.02) as well as high EuroSCORE II (p=0.013), hemoglobin level before surgery (p = 0.002) and the presence of diabetes and chronic kidney disease (p=0.03) were independent predictors of AKI after open-heart surgery. In patients who developed AKI, the duration of artificial lung ventilation was increased (21.3 vs 9.9 hours p = 0.001) and the duration of stay in the intensive care unit (4.3 vs. 1.9 days, P = 0.02).&lt;br /&gt; &lt;b&gt;&amp;nbsp;Conclusion:&lt;/b&gt;&lt;br /&gt; Patients often have AKI after heart surgery. EuroSCORE II, gender, diabetes, time of cardiopulmonary bypass and chronic kidney disease are independent predictors of AKI development. The appearance of AKI is due to an unfavorable outcome of events. The appearance of acute kidney injury is associated with adverse consequences.&lt;br /&gt; &lt;b&gt;&amp;nbsp;Key words: &lt;/b&gt;Acute kidney injury, cardiac surgery, predictors of AKI, postoperative period.&lt;br /&gt; &lt;br /&gt; &amp;nbsp;&lt;b&gt;Conflict of interests: &lt;/b&gt;The authors declare no conflict of interest.

EValuating the Effect of periopeRaTIve empaGliflOzin on cardiac surgery associated acute kidney injury: rationale and design of the VERTIGO study.

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a serious complication in patients undergoing cardiac surgery with extracorporeal circulation (ECC) that increases postoperative complications and mortality. CSA-AKI develops due to a combination of patient- and surgery-related risk factors that enhance renal ischemia-reperfusion injury. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) such as empagliflozin reduce renal glucose reabsorption, improving tubulo-glomerular feedback, reducing inflammation and decreasing intraglomerular pressure. Preclinical studies have observed that SGLT2i may provide significant protection against renal ischemia-reperfusion injury due to their effects on inadequate mitochondrial function, reactive oxygen species activity or renal peritubular capillary congestion, all hallmarks of CSA-AKI. The VERTIGO (EValuating the Effect of periopeRaTIve empaGliflOzin) trial is a Phase 3, investigator-initiated, randomized, double-blind, placebo-controlled, multicenter study that aims to explore whether empagliflozin can reduce the incidence of adverse renal outcomes in cardiac surgery patients. The VERTIGO study (EudraCT: 2021-004938-11) will enroll 608 patients that require elective cardiac surgery with ECC. Patients will be randomly assigned in a 1:1 ratio to receive either empagliflozin 10mg orally daily or placebo. Study treatment will start 5days before surgery and will continue during the first 7days postoperatively. All participants will receive standard care according to local practice guidelines. The primary endpoint of the study will be the proportion of patients that develop major adverse kidney events during the first 90days after surgery, defined as ≥25% renal function decline, renal replacement therapy initiation or death. Secondary, tertiary and safety endpoints will include rates of AKI during index hospitalization, postoperative complications and observed adverse events. The VERTIGO trial will describe the efficacy and safety of empagliflozin in preventing CSA-AKI. Patient recruitment is expected to start in May 2024.

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.

Cardiac Surgery Associated Acute Kidney Injury - Incidence, Risk Factors, Outcomes, and Risk Score Validation from a Single Centre in Bahrain

Background: Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication in patients undergoing cardiac surgery. Early prediction of acute kidney injury (AKI) is crucial to estimate and communicate the prognosis and outcome of surgery. This research is particularly significant as it addresses the need for validation of risk scores in non-Caucasian populations with a higher incidence of risk factors, potentially leading to improved patient care and outcomes. Objective: This prospective study aimed to investigate the association between socio-demographic and clinical variables in patients undergoing cardiac surgery in a single center in Bahrain and their correlation with a predictive risk score. Methods: This comprehensive study included 100 patients who underwent cardiac surgery. The distribution of study subjects was meticulously assessed based on the kidney disease: Improving Global Outcomes (KDIGO) classification for AKI. The association of AKI with socio-demographic and clinical variables was rigorously analyzed using chi-square tests and logistic regression analysis and compared to the predicted incidence from the Acute Kidney Injury after Cardiac Surgery (AKICS) score, ensuring the reliability and accuracy of our findings. Results: Among the study subjects, 65% were not affected by acute kidney injury (AKI). In contrast, 19% were classified as having Stage 1 AKI, 8% as Stage 2, and 8% as Stage 3. Additionally, 2% of the patients required dialysis. The findings of our study underscore the significant impact of AKI on hospital stay and the need for dialysis. Female gender, previous myocardial infarction, UF heparin use, and elevated preoperative creatinine levels were significantly associated with AKI. The AKICS score was found to predict AKI in our patients, with a sensitivity of 91% and a specificity of 46.9%. Conclusion: Female gender, previous myocardial infarction, UF heparin use, and elevated preoperative creatinine levels were found to be independent predictors of AKI. We found that patients with AKI had a significantly longer hospital stay duration. The AKICS score has been validated in our local cohort of Middle Eastern patients with high sensitivity. Keywords: Acute kidney injury; Cardiac surgery; Risk factors; Socio-demographic factors; Clinical variables

Could plasma viscosity play a role in cardiac-surgery associated acute kidney injury?

Could plasma viscosity play a role in cardiac-surgery associated acute kidney injury?

Early versus delayed initiation of renal replacement therapy in cardiac-surgery associated acute kidney injury: an economic perspective.

Timing for renal replacement therapy (RRT) initiation for cardiac-surgery associated acute kidney surgery (CSA-AKI) is subject to debate. Evidence suggests earlier initiation leads to shorter length of stay (LoS). We investigated differences in healthcare costs associated with timing of RRT initiation in CSA-AKI. A cost-consequences model compared costs of Early (<24 h) vs. Delayed (>24 h) RRT initiation. Data were from the ELAIN trial in Germany, and the HiDenIC database, a US multi-hospital database. Resource utilization was determined by RRT duration, ICU, and hospital LoS. All resources were costed from a US healthcare perspective. Extensive sensitivity analyses (SA) were conducted, notably regarding the proportion of patients not initiated on RRT with the Delayed strategy. Early RRT initiation exhibited cost savings compared to Delayed RRT initiation. With ELAIN data, savings reached -$122,188 (ranging from -$157,707 to -$74,763 in the SA). Findings were confirmed with HiDenIC data; Early RRT initiation showed savings of -$77,303 (ranging from -$108,971 to -$47,012 in the SA). Our costing model indicates that Early RRT initiation for CSA-AKI may result in appreciable cost savings. Delaying RRT, in the setting of CSA-AKI, may lead to longer LoS and increased healthcare costs.

Neurodevelopmental Outcomes in Infants With Cardiac Surgery Associated Acute Kidney Injury

BackgroundInfants who undergo surgery for congenital heart disease are at risk of neurodevelopmental delay. Cardiac surgery-associated acute kidney injury (CS-AKI) is common but its association with neurodevelopment has not been explored. MethodsThis was a single-center retrospective observational study of infants who underwent cardiac surgery in the first year of life who had neurodevelopmental testing using the Bayley Scale for Infant Development, third edition. Single and recurrent episodes of stages 2 and 3 CS-AKI were determined. ResultsOf 203 children with median age at first surgery of 12 days, 31% had one or more episodes of severe CS-AKI; of those, 16% had recurrent CS-AKI. Median age at neurodevelopmental assessment was 20 months. The incidence of delay was similar for patients with and patients without CS-AKI but all children with recurrent CS-AKI had a delay in one or more domains and had significantly lower scores in all three domains, namely, cognitive, language, and motor. ConclusionsThis study has assessed the association of CS-AKI with neurodevelopmental delay after surgery for congenital heart disease in infancy. Infants who have recurrent CS-AKI in the first year of life are more likely to be delayed and have lower neurodevelopmental scores.

Rationale and Design of Assessing the Effectiveness of Short-Term Low-Dose Lithium Therapy in Averting Cardiac Surgery-Associated Acute Kidney Injury: A Randomized, Double Blinded, Placebo Controlled Pilot Trial

Background: Burgeoning pre-clinical evidence suggests that therapeutic targeting of glycogen synthase kinase 3β (GSK3β), a convergence point of multiple cellular protective signaling pathways, confers a beneficial effect on acute kidney injury (AKI) in experimental models. However, it remains unknown if GSK3β inhibition likewise mitigates AKI in humans. Cardiac surgery associated acute kidney injury (CSA-AKI) poses a significant challenge for clinicians and currently the only treatment available is general supportive measures. Lithium, an FDA approved mood stabilizer, is the best-known GSK3β inhibitor and has been safely used for over half a century as the first line regimen to treat bipolar affective disorders. This study attempts to examine the effectiveness of short term low dose lithium on CSA-AKI in human patients.Methods/Design: This is a single center, prospective, randomized, double blinded, placebo controlled pilot study on patients undergoing cardiac surgery with cardiopulmonary bypass. Patients will be randomized to receive a small dose of lithium or placebo treatment for three consecutive days. Renal function will be measured via creatinine as well as novel AKI biomarkers. The primary outcome is incidence of AKI according to Acute Kidney Injury Network (AKIN) criteria, and secondary outcomes include receipt of new dialysis, days on dialysis, days on mechanical ventilation, infections within 1 month of surgery, and death within 90 days of surgery.Discussion: As a standard selective inhibitor of GSK3β, lithium has been shown to exert a beneficial effect on tissue repair and regeneration upon acute injury in multiple organ systems, including the central nervous system and hematopoietic system. In experimental AKI, lithium at small doses is able to ameliorate AKI and promote kidney repair. Successful completion of this study will help to assess the effectiveness of lithium in CSA-AKI and could potentially pave the way for large-scale randomized trials to thoroughly evaluate the efficacy of this novel regimen for preventing AKI after cardiac surgery.Trial Registration: This study was registered prospectively on the 17th February 2017 at ClinicalTrials.gov (NCT03056248, https://clinicaltrials.gov/ct2/show/NCT03056248?term=NCT03056248&draw=2&rank=1).

P0611COMPARISON OF FOUR PREDICTIVE SCORING MODELS AS ASSESSMENT TOOLS FOR CARDIAC SURGERY ASSOCIATED ACUTE KIDNEY INJURY IN POST CARDIAC SURGERY PATIENTS IN A PHILIPPINE LOCAL TERTIARY HOSPITAL FROM JANUARY 2010- JANUARY 2019

Abstract Background and Aims Cardiac surgery associated acute kidney injury is the most common cause of hospital acquired acute kidney injury in the intensive unit after sepsis. In Asia, incidence ranges from 17 to 49%, with 2 to 6 % of patients requiring dialysis after developing acute kidney injury. Its occurrence has shown increased morbidity, length of hospital stay, and utilization of resources which affect overall outcome of the patients. These patients face a combination of renal stressors and some patient populations deserve special consideration with regards to the risk factors identified preoperatively. Therefore, early prediction of cardiac surgery associated acute kidney injury is optimal. This study aims to compare the clinical values of the Cleveland Clinical Score, Mehta Score, Simplified Renal Index and Acute Kidney Injury following Cardiac Surgery Score in predicting cardiac surgery-associated acute kidney injury among patients who underwent cardiac surgery in Perpetual Succour Hospital, Cebu City from January 2010- January 2019. Method A chart review was done to all patients who underwent open heart surgery during the time period of January 2010 to January 2019. The patients who developed cardiac surgery associated- acute kidney injuries were identified using the four different predictive scoring methods. Binary logistic regression was used to describe the relationship between the development of CSA- AKI and the four scoring methods as its predictors. Confidence interval is set at 95%, comparison significant at &amp;lt;0.05, hypotheses tested at 0.05 level of significance. Therefore, if the p-value is less than or equal to the significance level, it can be concluded that there is a statistically significant association between the response variable and the predictor. Results There were a total of 114 cases of open heart surgeries. A sample size population of 86 were reviewed, and was divided into 2 groups, there were 43 patients (50%) who developed cardiac surgery associated acute kidney injury and 43 patients (50%) who did not develop CSA- AKI. Patients with recorded variables useful in all scoring systems were included. The p- values for the Cleveland Clinical Score and Simplified Renal Index are greater than the significance level. With the p- values less than the significance level, there is statistically significant association between the Mehta (p value 0.019) and AKICS score (p value 0.011) and the development of CSA- AKI. The odds ratios for both Mehta Score (1.10) and AKICS Score (1.19) are also greater than 1, indicating that AKI is more likely to occur if the Mehta score or the AKICS Score increases. Conclusion In our single- center study, acute kidney injury was more likely if the scores for both Mehta and AKICS scoring system methods increase. This supports that either Mehta or the AKICS scoring systems are useful methods that can be employed to predict cardiac surgery-associated acute kidney injury among patients who underwent cardiac surgery.

Sodium Bicarbonate Infusion to Reduce Cardiac Surgery–Associated Acute Kidney Injury

Cardiac surgery-associated acute kidney injury occurs in up to 50% of patients and is associated with increased mortality and morbidity. This study aimed to discover if perioperative urinary alkalinization with sodium bicarbonate infusion reduces the prevalence of cardiac surgery-associated acute kidney injury. This study was a phase IIb multicenter double-blind randomized controlled trial. This study was conducted in three tertiary hospitals in New Zealand and Australia. A total of 427 patients scheduled to undergo elective cardiac surgery, who were at increased risk of development of cardiac surgery-associated acute kidney injury using recognized risk factors. Patients were randomly allocated to receive either sodium bicarbonate (n = 215) or sodium chloride (n = 212) infusion, commencing at the start of anesthesia, in a dose of 0.5 mEq/kg/hr for the first hour and then 0.2 mmol/kg/hr for 23 hours. The primary outcome measure was the number of patients with development of cardiac surgery-associated acute kidney injury, defined as an increase in creatinine greater than 25% or 0.5 mg/dL (44 µmol/L) from baseline to peak value within the first five postoperative days. Significant differences among the groups in both plasma and urinary biochemistry were achieved 6 hours after commencement of the infusion, and these changes persisted for more than 24 hours. A total of 100 out of 215 patients (47% [95% CI, 40%-53%]) in the sodium bicarbonate group and 93 of 212 patients (44% [95% CI, 37%-51%]) in the sodium chloride group with development of acute kidney injury within the first five postoperative days (p = 0.58). There were also no significant differences in ventilation hours, ICU or hospital length of stay, or mortality. Perioperative alkalinization of blood and urine using an infusion of sodium bicarbonate did not result in a decrease in the prevalence of acute kidney injury in patients following cardiac surgery.

Absent Renal Blood Flow Diagnosed by Transesophageal Echocardiography During Cardiopulmonary Bypass

CARDIAC SURGERY–ASSOCIATED acute kidney injury (CSA-AKI) is reported to occur in up to 30% of cardiac surgical patients, 1 Rosner M.H. Okusa M.D. Acute kidney injury associated with cardiac surgery. Clin J Am Soc Nephrol. 2006; 1: 19-32 Crossref PubMed Scopus (825) Google Scholar with around 1% requiring hemodialysis. 2 Wijeysundra D.N. Karkouti K. Beattie W.S. et al. Improving the identification of patients at risk of postoperative renal failure after cardiac surgery. Anesthesiology. 2006; 104: 65-72 Crossref PubMed Scopus (100) Google Scholar The severity of CSA-AKI can be described using the RIFLE criteria (risk, injury, failure, loss and end-stage renal failure) 3 Bellomo R. Ronco C. Kellum J.A. et al. Acute renal failure—Definition, outcome measures, animal models, fluid therapy and information technology needs: The Second International Consensus Conference of the Acute Dialysis Quality Initiative (ADQI) Group. Crit Care. 2004; 8: R204-R212 Crossref PubMed Google Scholar or AKIN (Acute Kidney Injury Network) criteria. 4 Mehta R.L. Kellum J.A. Shah S.V. et al. Acute Kidney Injury NetworkReport of an initiative to improve outcomes in acute kidney injury. Crit Care. 2007; 11: R31 Crossref PubMed Scopus (5259) Google Scholar

RIFLE Criteria for Cardiac Surgery–Associated Acute Kidney Injury: Risk Factors and Outcomes

The aims of this study were to identify risk factors and evaluate the association with clinical outcomes of postoperative cardiac surgery-associated acute kidney injury (CSA-AKI). Data from 2488 consecutive adult patients were analyzed. Patients were classified as having CSA-AKI based on the risk, injury, failure, loss of kidney function, and end-stage kidney disease (RIFLE) criteria using peak postoperative creatinine in the postoperative intensive care unit (ICU). Multiple stepwise logistic regression analysis was used to identify independent risk factors for CSA-AKI. CSA-AKI occurred in 584 patients (23.5%). CSA-AKI patients had significantly longer aortic cross-clamp and cardiopulmonary bypass times. Furthermore, CSA-AKI patients had higher hospital mortality (5.5% vs 1.5%, P<.001) and significantly longer ICU and hospital stays. Independent risk factors for CSA-AKI were age, peripheral vascular disease, hypertension, left ventricular ejection fraction, cardiopulmonary bypass time, and surgery on the thoracic aorta. In conclusion, patients who develop CSA-AKI have a higher preoperative risk profile, more complex surgery, and worse clinical outcomes.

Cardiac-surgery associated acute kidney injury requiring renal replacement therapy. A Spanish retrospective case-cohort study

BackgroundAcute kidney injury is among the most serious complications after cardiac surgery and is associated with an impaired outcome. Multiple factors may concur in the development of this disease. Moreover, severe renal failure requiring renal replacement therapy (RRT) presents a high mortality rate. Consequently, we studied a Spanish cohort of patients to assess the risk factors for RRT in cardiac surgery-associated acute kidney injury (CSA-AKI).MethodsA retrospective case-cohort study in 24 Spanish hospitals. All cases of RRT after cardiac surgery in 2007 were matched in a crude ratio of 1:4 consecutive patients based on age, sex, treated in the same year, at the same hospital and by the same group of surgeons.ResultsWe analyzed the data from 864 patients enrolled in 2007. In multivariate analysis, severe acute kidney injury requiring postoperative RRT was significantly associated with the following variables: lower glomerular filtration rates, less basal haemoglobin, lower left ventricular ejection fraction, diabetes, prior diuretic treatment, urgent surgery, longer aortic cross clamp times, intraoperative administration of aprotinin, and increased number of packed red blood cells (PRBC) transfused. When we conducted a propensity analysis using best-matched of 137 available pairs of patients, prior diuretic treatment, longer aortic cross clamp times and number of PRBC transfused were significantly associated with CSA-AKI.Patients requiring RRT needed longer hospital stays, and suffered higher mortality rates.ConclusionCardiac-surgery associated acute kidney injury requiring RRT is associated with worse outcomes. For this reason, modifiable risk factors should be optimised and higher risk patients for acute kidney injury should be identified before undertaking cardiac surgery.

The Pathophysiology of Cardiac Surgery-Associated Acute Kidney Injury (CSA-AKI)

Cardiac surgery associated acute kidney injury (CSA-AKI) is a significant clinical problem. Its pathogenesis is complex and multifactorial. It likely involved at least six major injury pathways: exogenous and endogenous toxins, metabolic factors, ischemia and reperfusion, neurohormonal activation, inflammation and oxidative stress. These mechanisms of injury are likely to be active at different times with different intensity and probably act synergistically. Because of such complexity and the small number of randomised controlled investigations in this field only limited recommendations can be made. Nonetheless, it appears important to avoid nephrotoxic drugs and desirable to avoid hyperglycemia in the peri-operative period. The duration of cardiopulmonary bypass should be limited whenever possible. Off-pump surgery, when indicated, may decrease the risk of AKI. Invasive hemodynamic monitoring focussed on attention to maintaining euvolemia, an adequate cardiac output and an adequate arterial blood pressure is desirable. Echocardiography may be useful in minimizing atheroembolic complications. The administration of N-acetylcysteine to protect the kidney from oxidative stress is not recommended. There is marked lack of randomised controlled trials in this field.