Higher post-CPB COP is associated with postoperative AKI in infants undergoing cardiopulmonary bypass

Abstract

Background There has been an ongoing debate surrounding the optimal range for plasma colloid oncotic pressure (COP) in infants during CPB. Previous studies have focused primarily on the impact of low COP, while little attention has been paid to the potential risks of high COP, which may also lead to adverse effects. This retrospective study aimed to investigate the relationship between post-CPB COP and postoperative AKI in neonates and infants under 10kg. Method This retrospective clinical study consecutively included neonates and infants under 10kg who were diagnosed with CHD and underwent cardiopulmonary bypass at our center between May 2020 and September 2022. According to the median value of post-CPB COP in the study population, infants were classified into the low COP group (post-CPB COP ≤ 16mmHg) and the high COP group (post-CPB COP > 16mmHg). Demographic information, CPB details, COP measurements, renal adverse events, and clinical outcomes were compared between the two groups. The independent association of post-CPB COP with postoperative AKI was identified and adjusted using multivariable logistic regression analysis. Results 131 neonates and infants with CHD under 10kg underwent cardiac surgery with CPB were included in the study. The incidence of postoperative AKI was significantly higher in the higher post-CPB COP group (COP >16mmHg) than lower post-CPB COP group (COP ≤ 16mmHg) [7(10%) vs. 17(27.9%), p = 0.008)]. A higher post-CPB COP level independently increased the risk of postoperative AKI[OR(95%CI) 1.259(1.029,1.541), p = 0.025], controlling for age, gender, cardiopulmonary duration, 25%ALB infusion per kg and circulatory arrest. Subgroup analysis showed that post-CPB COP above 16 was an independent predictor for postoperative AKI[OR(95%CI) 4.985(1.315, 18.895), p = 0.018] in infants ≤ 6 months. Conclusion The present study demonstrated that elevated post-CPB COP was associated with increased risks of postoperative AKI in neonates and infants under 10kg, especially in infants below 6 months.