Development and internal validation of a prediction model for acute kidney injury following cardiac valve replacement surgery

Diagnostic accuracy of NT-proBNP to predict the incidence of CSA-AKI: A systematic review and meta-analysis

BACKGROUND

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a severe complication following cardiac surgery. Early identification and diagnosis are critical. In this study, we aim to systematically assess the diagnostic value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) for CSA-AKI.

METHODS

The PubMed, Embase, Web of Science, and Cochrane Library databases were searched from January 1971 to October 2023 to identify prospective observational and retrospective observational studies. Data extraction and study screening were carried out independently by 2 authors. The methodological quality of the included studies was evaluated by the Quality Assessment of Diagnostic Accuracy Studies 2 standards, and all statistical analyses were conducted by Stata 15.0.

RESULTS

Seven studies including 37,200 patients were identified. The pooled sensitivity of 0.67 (95% credible interval [CI] = 0.56-0.77), specificity of 0.55 (95% CI = 0.45-0.64), area under the summary receiver operating characteristic curve of 0.65 (95% CI = 0.60-0.69), positive likelihood ratio of 1.5 (95% CI = 1.2-1.8), negative likelihood ratio of 0.60 (95% CI = 0.46-0.79), and diagnostic odds ratio of 2 (95% CI = 2-4) suggested that patients with higher preoperative NT-proBNP levels (pg/mL) are at higher risk of developing acute kidney injury after cardiac surgery. However, NT-proBNP lacks sufficient sensitivity and specificity to reliably predict CSA-AKI.

CONCLUSION

Our findings suggest that the diagnostic accuracy of NT-proBNP to predict the incidence of CSA-AKI is limited. However, we provide novel perspectives on the early detection of CSA-AKI biomarkers, and it is urgent to identify more precise and practical biomarkers for the early diagnosis of CSA-AKI.

Development and Validation of a Nomogram for Predicting Acute Kidney Injury in Pediatric Patients Undergoing Cardiac Surgery

Acute kidney injury (AKI) is a common complication after cardiac surgery and associated with adverse outcomes. The purpose of this study is to construct a nomogram to predict the probability of postoperative AKI in pediatric patients undergoing cardiac surgery. We conducted a single-center retrospective cohort study of 1137 children having cardiac surgery under cardiopulmonary bypass. We randomly divided the included patients into development and validation cohorts at a ratio of 7:3. The least absolute shrinkage and selection operator regression model was used for feature selection. We constructed a multivariable logistic regression model to select predictors and develop a nomogram to predict AKI risk. Discrimination, calibration and clinical benefit of the final prediction model were evaluated in the development and validation cohorts. A simple nomogram was developed to predict risk of postoperative AKI using six predictors including age at operation, cyanosis, CPB duration longer than 120 min, cross-clamp time, baseline albumin and baseline creatinine levels. The area under the receiver operator characteristic curve of the nomogram was 0.739 (95% CI 0.693-0.786) and 0.755 (95% CI 0.694-0.816) for the development and validation cohort, respectively. The calibration curve showed a good correlation between predicted and observed risk of postoperative AKI. Decision curve analysis presented great clinical benefit of the nomogram. This novel nomogram for predicting AKI after pediatric cardiac surgery showed good discrimination, calibration and clinical practicability.

Postoperative Hyperuricemia-A Risk Factor in Elective Cardiosurgical Patients

Hyperuricemia is a well-known cardiovascular risk factor. The aim of our study was to investigate the connection between postoperative hyperuricemia and poor outcomes after elective cardiac surgery compared to patients without postoperative hyperuricemia. In this retrospective study, a total of 227 patients after elective cardiac surgery were divided into two groups: 42 patients with postoperative hyperuricemia (mean age 65.14 ± 8.9 years) and a second group of 185 patients without it (mean age 62.67 ± 7.45 years). The time spent on mechanical ventilation (hours) and in the intensive care unit (days) were taken as the primary outcome measures while the secondary measure comprised postoperative complications. The preoperative patient characteristics were similar. Most of the patients were men. The EuroSCORE value of assessing the risk was not different between the groups nor the comorbidities. Among the most common comorbidities was hypertension, seen in 66% of all patients (69% in patients with postoperative hyperuricemia and 63.7% in those without it). A group of patients with postoperative hyperuricemia had a prolonged time of treatment in the intensive care unit (p = 0.03), as well as a prolonged duration of mechanical ventilation (p < 0.01) and a significantly higher incidence of the following postoperative complications: circulatory instability and/or low cardiac output syndrome (LCOS) (χ2 = 4486, p < 0.01), renal failure and/or continuous venovenous hemodiafiltration (CVVHDF's) (χ2 = 10,241, p < 0.001), and mortality (χ2 = 5.22, p < 0.01). Compared to patients without postoperative hyperuricemia, elective cardiac patients with postoperative hyperuricemia have prolonged postoperative treatment in intensive care units, extended durations of mechanically assisted ventilation, and a higher incidence of postoperative circulatory instability, renal failure, and death.