Risk factors of acute kidney injury in children after cardiac surgery

Abstract

Background: The objective of this retrospective study was to determine the risk factors for acute kidney injury (AKI), including albumin, in children who underwent cardiac surgery. In addition, we evaluated the association between preoperative serum albumin level and postoperative AKI in these patients.

Methods: This retrospective study included 505 pediatric patients who underwent congenital cardiac surgery. Preoperative and perioperative risk factors for AKI, including serum albumin level, were assessed. AKI incidence within 7 postoperative days was determined using the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Multivariable logistic regression analysis was performed to evaluate the association between possible risk factors and postoperative AKI.

Results: Of 505 pediatric patients, 185 (36.6%) developed postoperative AKI. The preoperative serum albumin level was associated with postoperative AKI (odds ratio [OR] 0.506, 95% confidence interval [CI] 0.325-0.788; P = 0.003). Other independent factors associated with AKI were age <12 months (OR 1.911, 95% CI 1.166-3.132; P = 0.007), preoperative pulmonary hypertension (OR 1.853, 95% CI 1.182-2.907; P = 0.01), and cardiopulmonary bypass (CPB) duration (OR 1.006, 95% CI 1.003-1.009; P = 0.002). Patients with AKI had higher incidence of postoperative complications, longer mechanical ventilation times, and more prolonged intensive care unit and hospital stays than patients without AKI.

Conclusions: Preoperative serum albumin level, age <12 months, preoperative pulmonary hypertension, and CPB duration were associated with risk for postoperative AKI in children who underwent congenital cardiac surgery.

Keywords: acute kidney injury; cardiac surgery; child; morbidity; serum albumin.