Preoperative Ionized Magnesium Levels and Risk of Acute Kidney Injury After Cardiac Surgery.

Although postoperative acute kidney injury (AKI) is a serious complication after cardiac surgery, preventive measures are limited. Despite the known association of preoperative low magnesium levels with cardiac surgery-related atrial fibrillation, the association between preoperative magnesium concentration and postoperative AKI has not been fully elucidated. This study evaluated the association between preoperative serum magnesium level and the development of AKI after cardiac surgery. Retrospective observational cohort study. Patients aged≥18 years who underwent cardiac surgery at 2 South Korean tertiary hospitals between 2006 and 2020 were identified from medical records. Patients with missing information, an estimated glomerular filtration rate<15mL/min/1.73m2, receiving maintenance dialysis, or a history of AKI treated by dialysis within 1 year before surgery were excluded. Preoperative serum magnesium levels. Postoperative AKI within 48 hours after surgery, defined using the Acute Kidney Injury Network (AKIN) criteria, and dialysis-treated AKI within 30 days after surgery. Multivariable logistic regression analysis. Among the 9,766 patients (median age, 64.0 years; 60.1% male), postoperative AKI and dialysis-treated AKI were observed in 40.1% and 4.3% patients, respectively. Postoperative AKI was more prevalent in patients with lower serum magnesium levels (44.9%, 41.4%, 39.4%, and 34.8% in quartiles 1-4, respectively). Multivariable logistic regression analysis revealed that the odds ratios (ORs) for postoperative AKI were progressively larger across progressively lower quartiles of serum magnesium concentration (adjusted ORs of 1.53 [95% CI, 1.33-1.76], 1.29 [95% CI, 1.12-1.48], 1.15 [95% CI, 1.01-1.31] for quartiles 1-3, respectively, relative to quartile 4, P for trend<0.001). Preoperative hypomagnesemia (serum magnesium level<1.09mg/dL) was also significantly associated with AKI (adjusted OR, 1.39 [95% CI, 1.10-1.77]) and dialysis-treated AKI (adjusted OR, 1.67 [95% CI, 1.02-2.72]). Causality could not be evaluated in this observational study. Lower serum magnesium levels were associated with a higher incidence of AKI in patients undergoing cardiac surgery.

Koh HB ，Jung CY ，Kim HW ，Kwon JY ，Kim NH ，Kim HJ ，Jhee JH ，Han SH ，Yoo TH ，Kang SW ，Park JT ... -  《-》

Association of early postoperative serum magnesium with acute kidney injury after cardiac surgery.

Xiong C ，Shi S ，Cao L ，Wang H ，Tian L ，Jia Y ，Zeng M ，Wang J ... -  《-》

Preoperative serum cystatin C combined with dipstick proteinuria predicts acute kidney injury after cardiac surgery.

Wang X ，Che M ，Xie B ，Xue S ，Yan Y ... -  《-》

Predicting acute kidney injury following nonemergent cardiac surgery: A preoperative scorecard.

To determine the predictors of postoperative acute kidney injury (AKI) following nonemergent cardiac surgery among patients with variable preoperative estimated glomerular filtration rate (eGFR) levels. A retrospective study of patients who underwent elective or in-hospital cardiac surgical procedures was performed between January 2006 and November 2015. The procedures included isolated coronary artery bypass grafting (CABG), isolated aortic valve replacement (AVR), or combined CABG and AVR. The primary outcome AKI (any stage) following nonemergent cardiac surgery utilizing the 2012 Kidney Disease-Improving Global Outcomes (KDIGO) criteria. Patients were categorized based on the following renal outcomes: mild AKI, severe AKI (KDIGO stage 2 or 3), and postoperative dialysis. Patients with G5 preoperative kidney function (including dialysis patients) were excluded. A total of 6675 patients were included in our study. The mean age was 66.8 years (SD ± 10.4), with 76.3% being males. A total of 4487 patients had normal or mildly decreased eGFR (G1 or G2) preoperatively (67.2%), while 1960 patients were in the G3 category (29.4%). Only 228 patients (3.4%) had G4 renal function. A total of 1453 (21.7%) patients experienced postoperative AKI. The need for postoperative dialysis occurred in 3.2% of the AKI subgroup. In-hospital mortality was higher among the AKI subgroup (7.2% vs. 0.5%; p < .0001). In an adjusted model, a lower preoperative eGFR category was the strongest predictor of AKI. A practical scorecard for the preoperative estimation of severe AKI for nonemergent cardiac procedures incorporating these parameters was developed. Preoperative eGFR is the strongest predictor of postoperative AKI in individuals undergoing nonemergent cardiac surgery. A practical scorecard incorporating preoperative predictors of AKI may allow informed decision-making and predict AKI following nonemergent cardiac surgery.

Mokhtar AT ，Tennankore K ，Doucette S ，Herman CR ... -  《-》

Association of Preoperative Urinary Uromodulin with AKI after Cardiac Surgery.

AKI is a serious complication after cardiac surgery. Although high urinary concentrations of the tubular protein uromodulin, a marker of tubular health, are associated with less AKI in animal models, its relationship in humans is unknown. A post hoc analysis of a prospective cohort study of 218 adults undergoing on-pump cardiac surgery between 2004 and 2011 was conducted. Multivariable logistic and linear regression analyses were used to evaluate the associations of preoperative urinary uromodulin-to-creatinine ratio with postoperative AKI (defined as a rise in serum creatinine of >0.3 mg/dl or >1.5 times baseline); severe AKI (doubling of creatinine or need for dialysis) and peak postoperative serum creatinine over the first 72 hours. Mean age was 68 years, 27% were women, 95% were white, and the median uromodulin-to-creatinine ratio was 10.0 μg/g. AKI developed in 64 (29%) patients. Lower urinary uromodulin-to-creatinine ratio was associated with higher odds for AKI (odds ratio, 1.49 per 1-SD lower uromodulin; 95% confidence interval, 1.04 to 2.13), which was marginally attenuated after multivariable adjustment (odds ratio, 1.43; 95% confidence interval, 0.99 to 2.07). The lowest uromodulin-to-creatinine ratio quartile was also associated with higher odds for AKI relative to the highest quartile (odds ratio, 2.94; 95% confidence interval, 1.19 to 7.26), which was slightly attenuated after multivariable adjustment (odds ratio, 2.43; 95% confidence interval, 0.91 to 6.48). A uromodulin-to-creatinine ratio below the median was associated with higher adjusted odds for severe AKI, although this did not reach statistical significance (odds ratio, 4.03; 95% confidence interval, 0.87 to 18.70). Each 1-SD lower uromodulin-to-creatinine ratio was associated with a higher adjusted mean peak serum creatinine (0.07 mg/dl per SD; 95% confidence interval, 0.02 to 0.13). Lower uromodulin-to-creatinine ratio is associated with higher odds of AKI and higher peak serum creatinine after cardiac surgery. Additional studies are needed to confirm these preliminary results.

Garimella PS ，Jaber BL ，Tighiouart H ，Liangos O ，Bennett MR ，Devarajan P ，El-Achkar TM ，Sarnak MJ ... -  《-》