Adverse renal effects associated with cardiopulmonary bypass.

Cardiac surgery on cardiopulmonary bypass (CPB) is associated with postoperative renal dysfunction, one of the most common complications of this surgical cohort. Acute kidney injury (AKI) is associated with increased short-term morbidity and mortality and has been the focus of much research. There is increasing recognition of the role of AKI as the key pathophysiological state leading to the disease entities acute and chronic kidney disease (AKD and CKD). In this narrative review, we will consider the epidemiology of renal dysfunction after cardiac surgery on CPB and the clinical manifestations across the spectrum of disease. We will discuss the transition between different states of injury and dysfunction, and, importantly, the relevance to clinicians. The specific facets of kidney injury on extracorporeal circulation will be described and the current evidence evaluated for the use of perfusion-based techniques to reduce the incidence and mitigate the complications of renal dysfunction after cardiac surgery.

Neurologic complications after cardiopulmonary bypass - A narrative review.

Neurologic complications, associated with cardiac surgery and cardiopulmonary bypass (CPB) in adults, are common and can be devastating in some cases. This comprehensive review will not only consider the broad categories of stroke and neurocognitive dysfunction, but it also summarises other neurological complications associated with CPB, and it provides an update about risks, prevention and treatment. Where appropriate, we consider the impact of off-pump techniques upon our understanding of the contribution of CPB to adverse outcomes.

Perioperative Management of the Patient at High-Risk for Cardiac Surgery-Associated Acute Kidney Injury.

Acute kidney injury (AKI) is one of the most common major complications of cardiac surgery, and is associated with increased morbidity and mortality. Cardiac surgery-associated AKI has a complex, multifactorial etiology, including numerous factors such as primary cardiac dysfunction, hemodynamic derangements of cardiac surgery and cardiopulmonary bypass, and the possibility of a large volume of blood transfusion. There are no truly effective pharmacologic therapies for the management of AKI, and, therefore, anesthesiologists, intensivists, and cardiac surgeons must remain vigilant and attempt to minimize the risk of developing renal dysfunction. This narrative review describes the current state of the scientific literature concerning the specific aspects of cardiac surgery-associated AKI, and presents it in a chronological fashion to aid the perioperative clinician in their approach to this high-risk patient group. The evidence was considered for risk prediction models, preoperative optimization, and the intraoperative and postoperative management of cardiac surgery patients to improve renal outcomes.

Pre-operative exercise and pyrexia as modifying factors in malignant hyperthermia (MH).

Malignant hyperthermia (MH) is a life-threatening reaction triggered by volatile anesthetics and succinylcholine. MH is caused by mutations in the skeletal muscle ryanodine receptor (RYR1) gene, as is rhabdomyolysis triggered by exertion and/or pyrexia. The discrepancy between the prevalence of risk genotypes and actual MH incidence remains unexplained. We investigated the role of pre-operative exercise and pyrexia as potential MH modifying factors. We included cases from 5 MH referral centers with 1) clinical features suggestive of MH, 2) confirmation of MH susceptibility on Contracture Testing (IVCT or CHCT) and/or RYR1 genetic testing, and a history of 3) strenuous exercise within 72 h and/or pyrexia >37.5 °C prior to the triggering anesthetic. Characteristics of MH-triggering agents, surgery and succinylcholine use were collected. We identified 41 cases with general anesthesias resulting in an MH event (GA+MH, n = 41) within 72 h of strenuous exercise and/or pyrexia. We also identified previous general anesthesias without MH events (GA-MH, n = 51) in the index cases and their MH susceptible relatives. Apart from pre-operative exercise and/or pyrexia, trauma and acute abdomen as surgery indications, emergency surgery and succinylcholine use were also more common with GA+MH events. These observations suggest a link between pre-operative exercise, pyrexia and MH.

Frailty and perioperative patient-reported disability in patients undergoing cardiac surgery: a pilot study.

BACKGROUND: Preoperative frailty may predispose patients to poorer outcomes in cardiac surgery; however, there are limited data concerning how preoperative frailty predicts patient-centred outcomes, such as patient-reported disability. Our objective was to evaluate the association between preoperative frailty and postoperative disability. METHODS: Patients were prospectively evaluated using the Comprehensive Assessment of Frailty score, separating patients into frail and non-frail cohorts. Disability levels were quantified using the WHO Disability Assessment Schedule (WHODAS) 2.0 in percentage of the maximum disability score, with disability defined as a value ≥25%. RESULTS: Frail patients had increased median [inter-quartile range] disability scores of 31 [16-45]% preoperatively, 29 [9-54]% at 1 month, and 15 [3-31]% at 3 months postoperatively, compared with disability scores in non-frail patients of 10 [5-17]%, 17 [6-29]%, and 2.1 [0-12.0]%, respectively. Preoperative frailty was associated with a reduced likelihood of patients being free of disability and alive at 3 months; adjusted odds ratio 0.51 (for age, European System for Cardiac Operative Risk Evaluation II, and WHODAS 2.0: 12-Part Questionnaire score); P=0.045. The trajectory of disability scores, assessed in percentage change from the preoperative baseline, showed non-frail patients had increased disability burden at 1 month, whereas frail patients had reduced disability burden (+4.2% vs -2.1%; P=0.04). Although the disability burden decreased for both groups at 3 months, this was most marked for frail patients (-6.3% vs -10.4%; P=0.02). CONCLUSIONS: Disability burden in frail patients improves continuously postoperatively, whereas in non-frail patients, it worsens at 1 month before improving at 3 months postoperatively. This positive trajectory of patient-centred outcomes in frail patients should be considered in preoperative decision-making.

Effect of high-flow nasal therapy on patient-centred outcomes in patients at high risk of postoperative pulmonary complications after cardiac surgery: a study protocol for a multicentre adaptive randomised controlled trial.

BACKGROUND: High-flow nasal therapy is a non-invasive form of respiratory support that delivers low-level, flow dependent positive airway pressure. The device can be better tolerated by patients than alternatives such as continuous positive airway pressure. The primary objective is to determine if prophylactic high-flow nasal therapy after tracheal extubation can result in an increase in the number of days alive and at home within the first 90 days after surgery, when compared with standard oxygen therapy. The co-primary objective is to estimate the incremental cost-effectiveness and cost-utility of high-flow nasal therapy vs standard oxygen therapy at 90 days, from the view-point of the public sector, the health service and patients. METHODS: This is an adaptive, multicentre, international parallel-group, randomised controlled trial with embedded cost-effectiveness analysis comparing the use of high-flow nasal therapy with control in patients at high risk of respiratory complications following cardiac surgery. Participants will be randomised before tracheal extubation and allocated either high-flow nasal therapy or standard oxygen therapy for a minimum of 16 h immediately post extubation. Participants will be followed up until 90 days after surgery. The total sample size needed to detect a 2-day increase in DAH90 with 90% power with an intention to treat analysis is 850 patients. The adaptive design includes an interim sample size re-estimation which will provide protection against deviations from the original sample size assumptions made from the single-centre pilot study and will allow for a maximum sample size increase to 1152 patients. DISCUSSION: Evidence to support routine use of high-flow nasal therapy will inform the development of effective enhanced recovery care bundles. Reducing complications should reduce length of stay and re-admission to hospital and provide an important focus for cost reduction. However; high-quality studies evaluating the clinical and cost effectiveness of high-flow nasal therapy after cardiothoracic surgery are lacking. TRIAL REGISTRATION: The study has been registered with ISRCTN ( ISRCTN14092678 , 13/05/2020) Clinicaltrials.gov Registration Pending.

Role of Hypothermia in Adult Cardiac Surgery Patients: A Systematic Review and Meta-analysis.

OBJECTIVE: To review studies that assessed systemic hypothermia as an organ protection strategy in adults undergoing cardiac surgery with cardiopulmonary bypass. DESIGN: A systematic review and meta-analysis. SETTING AND PARTICIPANTS: Randomized controlled trials, irrespective of blinding, language, publication status, and date of publication, were identified by searching the Cochrane Central register of Controlled Trials, MEDLINE, and Embase until November 2020. Risk of bias assessment was performed according to Cochrane methodology. Treatment effects were expressed as risk ratios and 95% confidence intervals. Heterogeneity was expressed as I2. INTERVENTIONS: Systemic hypothermia. MEASUREMENTS AND MAIN RESULTS: Forty-eight trials enrolling 6,690 patients were included in the analysis. Methodologic quality of the studies included was low, mostly due to insufficient allocation concealment or blinding. Random-effects meta-analysis did not resolve uncertainty as to the risks and benefits for hypothermia versus normothermia for key primary and secondary outcomes, including mortality (1.21, 0.94 to 1.56, I2 = 0%) and brain injury (0.87, 0.67 to 1.14, I2 = 0%). Sensitivity analyses restricted to trials at low risk of important bias demonstrated higher mortality with hypothermia (1.70, 1.05 to 2.75, I2 = 0%), with little or no treatment effect on brain injury (1.01, 0.69 to 1.49, I2 = 0%). There was no interaction between cardioplegia temperature and the effects of cardiopulmonary bypass temperature on outcomes. There was insufficient evidence to assess the effects of hypothermia in noncoronary artery bypass graft surgery. CONCLUSION: The existing evidence for an organ-protective effect of hypothermia in adult cardiac surgery is of low quality and inconsistent.

Neuromonitoring and Neurocognitive Outcomes in Cardiac Surgery: A Narrative Review.

Neurocognitive dysfunction after cardiac surgery can present with diverse clinical phenotypes, which include postoperative delirium, postoperative cognitive dysfunction, and stroke, and it presents a significant healthcare burden for both patients and providers. Neurologic monitoring during cardiac surgery includes several modalities assessing cerebral perfusion and oxygenation (near-infrared spectroscopy, transcranial Doppler and jugular venous bulb saturation monitoring) and those that measure cerebral function (processed and unprocessed electroencephalogram), reflecting an absence of a single, definitive neuromonitor. This narrative review briefly describes the technologic basis of these neuromonitoring modalities, before exploring their use in clinical practice, both as tools to predict neurocognitive dysfunction, and with a bundle of interventions designed to optimize cerebral oxygen supply, with the aim of reducing postoperative delirium and cognitive dysfunction following cardiac surgery.

Cardiac Surgery Associated AKI Prevention Strategies and Medical Treatment for CSA-AKI.

Acute kidney injury (AKI) is common after cardiac surgery. To date, there are no specific pharmacological therapies. In this review, we summarise the existing evidence for prevention and management of cardiac surgery-associated AKI and outline areas for future research. Preoperatively, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers should be withheld and nephrotoxins should be avoided to reduce the risk. Intraoperative strategies include goal-directed therapy with individualised blood pressure management and administration of balanced fluids, the use of circuits with biocompatible coatings, application of minimally invasive extracorporeal circulation, and lung protective ventilation. Postoperative management should be in accordance with current KDIGO AKI recommendations.

Multicenter International Survey on Cardiopulmonary Bypass Perfusion Practices in Adult Cardiac Surgery

OBJECTIVES: To assess current practice in adult cardiac surgery during cardiopulmonary bypass (CPB) across European and non-European countries. DESIGN: International, multicenter, web-based survey including 28 multiple choice questions addressing hemodynamic and tissue oxygenation parameters, organ protection measures, and the monitoring and usage of anesthetic drugs as part of the anesthetic and perfusion practice during CPB. SETTING: Online survey endorsed by the European Association of Cardiothoracic Anesthesiologists. PARTICIPANTS: Representatives of anesthesiology departments in European and non-European adult cardiac surgical centers. INTERVENTIONS: None. Measurements and Main Results: The survey was distributed via e-mail to European Association of Cardiothoracic Anesthesiologists members (n = 797) and kept open for 1 month. The response rate was 34% (n = 271). After exclusion of responses from the same centers and of incomplete answers, data from 202 cardiac centers in 56 countries, of which 67% of centers were university hospitals, were analyzed. Optimization of pump flows and tissue oxygenation parameters during CPB were applied by the majority of centers, with target flow rates of >2.2 L/min/m2 in 93% (n = 187) of centers and mean arterial blood pressures between 51 and 90 mmHg in 85% (n = 172). Hemoglobin transfusion triggers were either individualized or between 7 and 8 g/dL in 92% (n = 186) of centers. Mixed venous oxyhemoglobin saturations were assessed routinely in 59% (n = 120) and lactate in 88% (n = 178) of cardiac surgery units. Noninvasive cerebral saturation monitoring was used in a subgroup of patients or routinely in 84% (n = 169) of sites, and depth-of-anesthesia monitoring was used routinely in 53% (n = 106). Transesophageal echocardiography and pulmonary artery catheters were used routinely or in subgroups of patients in 97% (n = 195) and 71% (n = 153) of centers, respectively. The preferred site for temperature monitoring was the nasopharynx in 66% (n = 134) of centers. Anesthetic techniques were variable, with 26% of centers (n = 52) using low-tidal-volume ventilation and 28% (n = 57) using continuous positive airway pressure during CPB. Volatile agents were used routinely as the only agent during CPB in 36% sites (n = 73) and propofol in 47% (n = 95). Other drugs routinely administered included magnesium in 45% (n = 91), steroids in 18% (n = 37), tranexamic acid in 88% (n = 177), and aprotinin in 15% (n = 30) of the centers. CONCLUSION: This international CPB survey revealed that techniques for optimization of pump flow and oxygenation during CPB usually were applied. Furthermore, cerebral and hemodynamic monitoring devices were frequently used during CPB. However, most CPB-related anesthetic techniques and medications were more variable. More high-quality randomized controlled trials are needed to assess anesthetic techniques and organ protection.

Prevention of Cardiac Surgery-Associated Acute Kidney Injury by Implementing the KDIGO Guidelines in High-Risk Patients Identified by Biomarkers: The PrevAKI-Multicenter Randomized Controlled Trial.

BACKGROUND: Prospective, single-center trials have shown that the implementation of the Kidney Disease: Improving Global Outcomes (KDIGO) recommendations in high-risk patients significantly reduced the development of acute kidney injury (AKI) after surgery. We sought to evaluate the feasibility of implementing a bundle of supportive measures based on the KDIGO guideline in high-risk patients undergoing cardiac surgery in a multicenter setting in preparation for a large definitive trial. METHODS: In this multicenter, multinational, randomized controlled trial, we examined the adherence to the KDIGO bundle consisting of optimization of volume status and hemodynamics, functional hemodynamic monitoring, avoidance of nephrotoxic drugs, and prevention of hyperglycemia in high-risk patients identified by the urinary biomarkers tissue inhibitor of metalloproteinases-2 [TIMP-2] and insulin growth factor-binding protein 7 [IGFBP7] after cardiac surgery. The primary end point was the adherence to the bundle protocol and was evaluated by the percentage of compliant patients with a 95% confidence interval (CI) according to Clopper-Pearson. Secondary end points included the development and severity of AKI. RESULTS: In total, 278 patients were included in the final analysis. In the intervention group, 65.4% of patients received the complete bundle as compared to 4.2% in the control group (absolute risk reduction [ARR] 61.2 [95% CI, 52.6-69.9]; P < .001). AKI rates were statistically not different in both groups (46.3% intervention versus 41.5% control group; ARR -4.8% [95% CI, -16.4 to 6.9]; P = .423). However, the occurrence of moderate and severe AKI was significantly lower in the intervention group as compared to the control group (14.0% vs 23.9%; ARR 10.0% [95% CI, 0.9-19.1]; P = .034). There were no significant effects on other specified secondary outcomes. CONCLUSIONS: Implementation of a KDIGO-derived treatment bundle is feasible in a multinational setting. Furthermore, moderate to severe AKI was significantly reduced in the intervention group.

Effect of sevoflurane on the inflammatory response during cardiopulmonary bypass in cardiac surgery: the study protocol for a randomized controlled trial.

BACKGROUND: Recent experimental evidence shows that sevoflurane can reduce the inflammatory response during cardiac surgery with cardiopulmonary bypass. However, this observation so far has not been assessed in an adequately powered randomized controlled trial. METHODS: We plan to include one hundred patients undergoing elective coronary artery bypass graft with cardiopulmonary bypass who will be randomized to receive either volatile anesthetics during cardiopulmonary bypass or total intravenous anesthesia. The primary endpoint of the study is to assess the inflammatory response during cardiopulmonary bypass by measuring PMN-elastase serum levels. Secondary endpoints include serum levels of other pro-inflammatory markers (IL-1ß, IL-6, IL-8, TNFα), anti-inflammatory cytokines (TGFß and IL-10), and microRNA expression in peripheral blood to achieve possible epigenetic mechanisms in this process. In addition clinical endpoints such as presence of major complications in the postoperative period and length of hospital and intensive care unit stay will be assessed. DISCUSSION: The trial may determine whether adding volatile anesthetic during cardiopulmonary bypass will attenuate the inflammatory response. TRIAL REGISTRATION: ClinicalTrials.gov NCT02672345 . Registered on February 2016 and updated on June 2020.

Effect of sevoflurane on the inflammatory response during cardiopulmonary bypass in cardiac surgery: the study protocol for a randomized controlled trial

Background: Recent experimental evidence shows that sevoflurane can reduce the inflammatory response during cardiac surgery with cardiopulmonary bypass. However, this observation so far has not been assessed in an adequately powered randomized controlled trial. Methods: We plan to include one hundred patients undergoing elective coronary artery bypass graft with cardiopulmonary bypass who will be randomized to receive either volatile anesthetics during cardiopulmonary bypass or total intravenous anesthesia. The primary endpoint of the study is to assess the inflammatory response during cardiopulmonary bypass by measuring PMN-elastase serum levels. Secondary endpoints include serum levels of other pro-inflammatory markers (IL-1ß, IL-6, IL-8, TNFα), anti-inflammatory cytokines (TGFß and IL-10), and microRNA expression in peripheral blood to achieve possible epigenetic mechanisms in this process. In addition, clinical endpoints such as presence of major complications in the postoperative period and length of hospital and intensive care unit stay will be assessed. Discussion: The trial may determine whether adding volatile anesthetic during cardiopulmonary bypass will attenuate the inflammatory response.

Multicenter International Survey on Cardiopulmonary Bypass Perfusion Practices in Adult Cardiac Surgery.

OBJECTIVES: To assess current practice in adult cardiac surgery during cardiopulmonary bypass (CPB) across European and non-European countries. DESIGN: International, multicenter, web-based survey including 28 multiple choice questions addressing hemodynamic and tissue oxygenation parameters, organ protection measures, and the monitoring and usage of anesthetic drugs as part of the anesthetic and perfusion practice during CPB. SETTING: Online survey endorsed by the European Association of Cardiothoracic Anesthesiologists. PARTICIPANTS: Representatives of anesthesiology departments in European and non-European adult cardiac surgical centers. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The survey was distributed via e-mail to European Association of Cardiothoracic Anesthesiologists members (n = 797) and kept open for 1 month. The response rate was 34% (n = 271). After exclusion of responses from the same centers and of incomplete answers, data from 202 cardiac centers in 56 countries, of which 67% of centers were university hospitals, were analyzed. Optimization of pump flows and tissue oxygenation parameters during CPB were applied by the majority of centers, with target flow rates of >2.2 L/min/m2 in 93% (n = 187) of centers and mean arterial blood pressures between 51 and 90 mmHg in 85% (n = 172). Hemoglobin transfusion triggers were either individualized or between 7 and 8 g/dL in 92% (n = 186) of centers. Mixed venous oxyhemoglobin saturations were assessed routinely in 59% (n = 120) and lactate in 88% (n = 178) of cardiac surgery units. Noninvasive cerebral saturation monitoring was used in a subgroup of patients or routinely in 84% (n = 169) of sites, and depth-of-anesthesia monitoring was used routinely in 53% (n = 106). Transesophageal echocardiography and pulmonary artery catheters were used routinely or in subgroups of patients in 97% (n = 195) and 71% (n = 153) of centers, respectively. The preferred site for temperature monitoring was the nasopharynx in 66% (n = 134) of centers. Anesthetic techniques were variable, with 26% of centers (n = 52) using low-tidal-volume ventilation and 28% (n = 57) using continuous positive airway pressure during CPB. Volatile agents were used routinely as the only agent during CPB in 36% sites (n = 73) and propofol in 47% (n = 95). Other drugs routinely administered included magnesium in 45% (n = 91), steroids in 18% (n = 37), tranexamic acid in 88% (n = 177), and aprotinin in 15% (n = 30) of the centers. CONCLUSION: This international CPB survey revealed that techniques for optimization of pump flow and oxygenation during CPB usually were applied. Furthermore, cerebral and hemodynamic monitoring devices were frequently used during CPB. However, most CPB-related anesthetic techniques and medications were more variable. More high-quality randomized controlled trials are needed to assess anesthetic techniques and organ protection.

Biomarker-guided implementation of the KDIGO guidelines to reduce the occurrence of acute kidney injury in patients after cardiac surgery (PrevAKI-multicentre): protocol for a multicentre, observational study followed by randomised controlled feasibility trial.

INTRODUCTION: Acute kidney injury (AKI) is a frequent complication after cardiac surgery with adverse short-term and long-term outcomes. Although prevention of AKI (PrevAKI) is strongly recommended, the optimal strategy is uncertain. The Kidney Disease: Improving Global Outcomes (KDIGO) guideline recommended a bundle of supportive measures in high-risk patients. In a single-centre trial, we recently demonstrated that the strict implementation of the KDIGO bundle significantly reduced the occurrence of AKI after cardiac surgery. In this feasibility study, we aim to evaluate whether the study protocol can be implemented in a multicentre setting in preparation for a large multicentre trial. METHODS AND ANALYSIS: We plan to conduct a prospective, observational survey followed by a randomised controlled, multicentre, multinational clinical trial including 280 patients undergoing cardiac surgery with cardiopulmonary bypass. The purpose of the observational survey is to explore the adherence to the KDIGO recommendations in routine clinical practice. The second phase is a randomised controlled trial. The objective is to investigate whether the trial protocol is implementable in a large multicentre, multinational setting. The primary endpoint of the interventional part is the compliance rate with the protocol. Secondary endpoints include the occurrence of any AKI and moderate/severe AKI as defined by the KDIGO criteria within 72 hours after surgery, renal recovery at day 90, use of renal replacement therapy (RRT) and mortality at days 30, 60 and 90, the combined endpoint major adverse kidney events consisting of persistent renal dysfunction, RRT and mortality at day 90 and safety outcomes. ETHICS AND DISSEMINATION: The PrevAKI multicentre study has been approved by the leading Research Ethics Committee of the University of Münster and the respective Research Ethics Committee at each participating site. The results will be used to design a large, definitive trial. TRIAL REGISTRATION NUMBER: NCT03244514.

Current Practice of Calcium Use During Cardiopulmonary Bypass Weaning: Results of an International Survey.

OBJECTIVES: To describe international practices on the use of calcium salts during cardiopulmonary bypass (CPB) weaning in adult cardiac surgery patients. DESIGN: Multiple-choice survey on current practice of CPB weaning. SETTING: Online survey using the SurveyMonkey platform. PARTICIPANTS: Departments of cardiac anesthesiology worldwide. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Out of 112 surveys sent, 100 centers from 32 countries replied. The majority of centers (88 of 100 = 88%) administer calcium salts intraoperatively: 71 of 100 (71%) are using these drugs for CPB weaning and 78 of 100 (78%) for correction of hypocalcemia. Among the 88 centers that use calcium salts intraoperatively, 66% (58 of 88) of respondents use calcium chloride, 22% (19 of 88) use calcium gluconate, and 12% (11 of 88) use both drugs. Calcium salts are routinely used during normal (47 of 71 centers = 66%) and difficult (59 of 71 centers = 83%) weaning from CPB. Doses of 5 to 15 mg/kg during termination of CPB were used by 55 of 71 centers (77%) either by bolus (39 of 71, 55%) or over a time period longer than 1 minute (32 of 71 = 45%). Norepinephrine is the most commonly used first line vasopressor or inotropic agent used to support hemodynamics during termination of CPB in 32 out of 100 centers (32%), and calcium is the second one, used by 23 out of 100 centers (23%). CONCLUSION: This survey demonstrates that the majority of cardiac centers use calcium in adult patients undergoing cardiac surgery, especially during weaning from CPB. There is variability on the type of drug, dose, and modality of drug administration.

A Multinational Observational Study Exploring Adherence With the Kidney Disease: Improving Global Outcomes Recommendations for Prevention of Acute Kidney Injury After Cardiac Surgery.

BACKGROUND: The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines recommend a bundle of different measures for patients at increased risk of acute kidney injury (AKI). Prospective, single-center, randomized controlled trials (RCTs) have shown that management in accordance with the KDIGO recommendations was associated with a significant reduction in the incidence of postoperative AKI in high-risk patients. However, compliance with the KDIGO bundle in routine clinical practice is unknown. METHODS: This observational prevalence study was performed in conjunction with a prospective RCT investigating the role of the KDIGO bundle in high-risk patients undergoing cardiac surgery. A 2-day observational prevalence study was performed in all participating centers before the RCT to explore routine clinical practice. The participating hospitals provided the following data: demographics and surgical characteristics, AKI rates, and compliance rates with the individual components of the bundle. RESULTS: Ninety-five patients were enrolled in 12 participating hospitals. The incidence of AKI within 72 hours after cardiac surgery was 24.2%. In 5.3% of all patients, clinical management was fully compliant with all 6 components of the bundle. Nephrotoxic drugs were discontinued in 52.6% of patients, volume optimization was performed in 70.5%, 52.6% of the patients underwent functional hemodynamic monitoring, close monitoring of serum creatinine and urine output was undertaken in 24.2% of patients, hyperglycemia was avoided in 41.1% of patients, and no patient received radiocontrast agents. The patients received on average 3.4 (standard deviation [SD] ±1.1) of 6 supportive measures as recommended by the KDIGO guidelines. There was no significant difference in the number of applied measures between AKI and non-AKI patients (3.2 [SD ±1.1] vs 3.5 [SD ±1.1]; P = .347). CONCLUSIONS: In patients after cardiac surgery, compliance with the KDIGO recommendations was low in routine clinical practice.