Background

Acute kidney injury (AKI) poses a significant challenge in pediatric cardiac surgery, having a profound impact on patient morbidity and mortality. This study aims to determine the incidence of AKI, explore novel biomarkers for early detection, assess potential risk factors along with preemptive strategies to minimize its incidence and compare the results with similar studies that did not use these interventions.

Methods

This prospective observational cohort study, conducted from October 2022 to June 2024 at a tertiary care center, involved 44 pediatric patients, aged three months to 15 years, undergoing cardiac surgery. Kidney function was assessed through preoperative and postoperative measurements of serum creatinine, urine output, blood urea, and newer biomarkers such as cystatin C and urine neutrophil gelatinase-associated lipocalin (NGAL). AKI was defined and classified using the Acute Kidney Injury Network (AKIN) criteria, based on increases in serum creatinine or reductions in urine output within the first three days post surgery. To reduce the risk of AKI, a low-dose vasopressin infusion and blood transfusion were administered to maintain renal perfusion and optimal hematocrit levels. The incidence of AKI was calculated and compared with other studies that did not utilize these strategies

Results

AKI occurred in 31.8% (n=14) of the pediatric patients undergoing cardiac surgery. To reduce the risk of AKI, preemptive low-dose vasopressin was used as a preventive strategy. Patients who developed AKI exhibited significant elevations in serum creatinine, blood urea, and cystatin C, with postoperative NGAL levels exceeding 50 ng/ml. The study found a strong correlation between lower intraoperative hematocrit levels (<30%) and a higher incidence of AKI (100% vs. 6.2%, p<0.001).

Conclusions

Effective management of intraoperative hematocrit levels and the preemptive use of vasopressin are promising strategies for reducing AKI risk by optimizing renal perfusion and function during cardiac surgery. Early detection through biomarkers like cystatin C and NGAL offers the potential for timely intervention and better patient outcomes. These findings contribute to improving risk assessment and perioperative management in pediatric patients vulnerable to AKI.