Background: 

Acute kidney injury (AKI) is a frequent complication of congenital heart surgery with cardiopulmonary bypass (CPB) in pediatric patients, contributing to significant morbidity and mortality.

Aim: 

To determine the prevalence and perioperative predictors of AKI after pediatric CPB.

Methods: 

In this single-center retrospective cohort study, medical records of 84 pediatric patients (<18 years) undergoing elective or urgent CPB-assisted congenital heart surgery (November 2018–December 2024) were reviewed. AKI was diagnosed using kidney disease: Improving Global Outcomes (KDIGO) criteria. Demographic, clinical, and laboratory variables were analyzed via univariate and multivariate logistic regression; predictive accuracy was assessed with receiver operating characteristic (ROC) analysis.

Results: 

AKI occurred in 32.1% of patients, predominantly KDIGO stage 1. Independent predictors included lower preoperative creatinine (OR = 0.019,P= 0.040), lower body weight (OR = 0.92, P= 0.024), and higher postoperative day 1 blood urea nitrogen (BUN) (OR = 1.05,P= 0.007). Preoperative creatinine (AUC = 0.82) and postoperative day 1 BUN (AUC = 0.73) had the highest discriminative ability. AKI was associated with prolonged intubation (P = 0.017), higher vasoactive-inotropic scores on postoperative days 1–3, and increased peritoneal dialysis rates (P = 0.032).

Conclusion: 

Lower baseline creatinine and body weight, along with elevated early postoperative BUN, independently predict AKI after pediatric CPB. Incorporating these parameters into perioperative risk models may facilitate early renal-protective strategies. Prospective studies with larger cohorts and biomarker integration are warranted.