Cardiac surgery related cardio-renal syndrome assessed by conventional and novel biomarkers - under or overestimated diagnosis?

Present Situation and Research Progress of Kidney Function Recoverability Evaluation of Acute Kidney Injury Patient

Acute kidney injury (AKI) is a critical illness in clinic. The guideline recommendation of kidney disease for improving global outcomes regards urine volume and creatinine as standards to evaluate kidney functions. However, urine volume and creatinine have a certain delay for kidney function evaluation, and these would be interfered by many factors. Whether the renal function of AKI patients can recover is very important, which affects the quality of life of patients. Therefore, the present study reviews the application situation and research progress of the recoverability evaluation of AKI patient kidney function from three aspects: conventional indexes, biomarkers, and imaging methods of kidney function.

The Impact of Acute Kidney Injury in the Perioperative Period on the Incidence of Postoperative Delirium in Patients Undergoing Coronary Artery Bypass Grafting-Observational Cohort Study

Recent data indicate that acute kidney damage leads to inflammation in the brain and other distant organs. The purpose of this study was to investigate the effect of acute kidney injury (AKI) according to the Kidney Disease Improving Global Outcome (KDIGO) criteria on the occurrence of postoperative delirium in patients undergoing coronary artery bypass grafting (CABG). We performed a retrospective cohort analysis that included all consecutive patients undergoing elective CABG. The CAM-ICU (Confusion Assessment Method for Intensive Care Unit) was used for delirium assessment. Patients were divided into four groups, depending on the occurrence of AKI in the perioperative period according to KDIGO criteria. Overall, 902 patients were included in the final analysis, the mean age was 65.95 ± 8.01 years, and 76.83% were males (693/957). The majority of patients presented with normal kidney function-baseline creatinine level of 0.91 ± 0.21 (mg/dL). The incidence of AKI in the perioperative setting was 22.17% (200/902). Postoperative delirium was diagnosed in 115/902 patients (12.75%). Compared with no AKI, the odds of developing POD were increased for KDIGO stage 1 (OR 2.401 (95% confidence interval 1.484–3.884), p < 0.001); KDIGO stage 2 (OR 3.387 (95% confidence interval 1.459–7.866), p = 0.005); and highest for KDIGO stage 3 (OR equal to 9.729 (95% confidence interval 2.675–35.382), p = 0.001). Acute kidney injury, based on AKI staging, should be regarded as an independent risk factor for postoperative delirium after cardiac surgery.

Biomarkers of Acute Kidney Injury after Cardiac Surgery: A Narrative Review

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a major and serious complication in patients undergoing cardiac surgery and is independently associated with perioperative mortality and mortality. Therapeutic intervention aiming at reversing kidney dysfunction seems disappointing across multiple settings. Consequently, attention has shifted from treatment to prevention and early detection. The Kidney Disease: Improving Global Outcomes (KDIGO) guidelines have unified diagnostic standards mainly based on the serum creatinine (Scr) level or urine output, but neither marker is kidney specific. Efforts have been made to identify novel biomarkers with high sensitivity and specificity. The diagnostic capabilities of neutrophil gelatinase-associated lipocalin (NGAL) and G1 cell cycle arrest biomarker as biomarkers have been confirmed in a large number of clinical trials. The utility of biomarkers of cardiac function and inflammation has been validated in clinical studies. Aiming to offer valuable information for further research, we summarize the progress in defining current markers relevant to CSA-AKI in the last three years.

Outcomes of Moderate-to-Severe Acute Kidney Injury following Left Ventricular Assist Device Implantation

BACKGROUND

Although acute kidney injury (AKI) is a common complication following cardiac surgery, less is known about the occurrence and consequences of moderate/severe AKI following left ventricular assist device (LVAD) implantation.

METHODS

All patients who had an LVAD implanted at our center from 2008 to 2016 were reviewed to determine the incidence of, and risk factors for, moderate/severe (stage 2/3) AKI and to compare postoperative complications and mortality rates between those with and those without moderate/severe AKI.

RESULTS

Of 246 patients, 68 (28%) developed moderate/severe AKI. A multivariable logistic regression comprising body mass index and prior sternotomy had fair predictive ability (area under the curve = 0.71). A 1-unit increase in body mass index increased the risk of moderate/severe AKI by 7% (odds ratio = 1.07; 95% confidence interval: 1.03-1.11); a prior sternotomy increased the risk more than 3-fold (odds ratio = 3.4; 95% confidence interval: 1.84-6.43). The group of patients with moderate/severe AKI had higher rates of respiratory failure and death than the group of patients with mild/no AKI. Patients with moderate/severe AKI were at 3.2 (95% confidence interval: 1.2-8.2) times the risk of 30-day mortality compared to those without. Even after adjusting for age and Interagency Registry for Mechanically Assisted Circulatory Support profile, those with moderate/severe AKI had 1.75 (95% confidence interval: 1.03-3.0) times the risk of 1-year mortality compared to those without.

DISCUSSION

Risk-stratifying patients prior to LVAD placement in regard to AKI development may be a step toward improving surgical outcomes.