One in Three Infants Develop Acute Kidney Injury After Cardiac Surgery: Study

While infants are highly susceptible to cardiac surgery-associated acute kidney injury (CS-AKI), comprehensive data from resource-limited clinical settings remains scarce. To address this gap, Dr. Rajesh Sharma and colleagues at Medanta, India, investigated the incidence, risk factors, and postoperative outcomes of CS-AKI in infants under one year undergoing cardiopulmonary bypass.

Therefore, the single-center, prospective observational study (September 2022–September 2023) evaluated 140 infants, excluding those with baseline renal dysfunction or preoperative mechanical support. The primary endpoints assessed the incidence of postoperative acute kidney injury and fluid overload, while secondary outcomes measured the need for kidney replacement therapy, mechanical ventilation duration, ICU length of stay, and overall mortality.

Key Clinical Findings of the Study Include:

• High Incidence Rate: Investigators observed that acute kidney injury occurred in a notable 33.6% (47 out of 140) of the infant cohort, with the majority developing the complication within a median of two postoperative days.

• Key Independent Predictors: Researchers identified that infants with underlying cyanotic heart disease (odds ratio 2.53), prolonged aortic cross-clamp times exceeding 60 minutes (odds ratio 3.78), and extended mechanical ventilation beyond 48 hours (odds ratio 6.01) faced a significantly elevated risk of renal impairment.

• Significant Mortality Impact: Experts revealed a substantially higher mortality rate in the affected group at 8.5% compared to 0% in the unaffected group, with all deceased infants experiencing severe postoperative sepsis and requiring urgent kidney replacement therapy.

• Prolonged Hospitalization Needs: Analysts documented that both the median ICU stay and total hospital duration were significantly extended for infants dealing with renal complications (5 and 9 days, respectively) when directly compared to those without such postoperative morbidities (4 and 8 days).

The results suggest that CS-AKI is a highly prevalent complication affecting 33.6% of infants, profoundly impacting overall patient morbidity by significantly extending necessary hospitalizations and substantially increasing the risk of early mortality.

Thus, the study concludes healthcare providers to consider implementing targeted perioperative management strategies aimed at actively reducing modifiable risk factors, such as prolonged surgical clamp times and postoperative sepsis, to steadily enhance infant recovery trajectories.

While slightly limited by the practical unavailability of novel serum or urinary biomarkers in the clinical setting, these critical insights softly highlight an encouraging pathway for future research to develop highly sensitive early predictive tools that can further safeguard this delicate pediatric population.

Reference

Sharma R, Gulia M, Bhan A, Akole R, Hu J, Mir FA, et al. Acute Kidney Injury in Infants Undergoing Cardiac Surgery Under Cardiopulmonary Bypass. Indian J Nephrol. 2026;36:216-20.