Prediction value of regional oxygen saturation in intestine and kidney for acute kidney injury in children with congenital heart disease after surgery

Objective: To study the prediction value of regional oxygen saturation (rSO2) in brain, intestine and kidney for acute kidney injury (AKI) in children with congenital heart disease after surgery. Methods: Fifty-seven children with congenital heart disease (CHD), whose weight >2.5 kg and age≤1 year were treated in Shanghai Children’s Medical Center, Shanghai Jiao Tong University School of Medicine from January 2020 to December 2020. The rSO2 of brain, intestine and kidney were monitored with near-infrared spectroscopy continuously for 48 h after surgery. The predictive values of cerebral, intestinal and renal rSO2 for occurrence and severity of postoperative AKI were analyzed. Results: Among 57 patients, postoperative AKI developed in 38 cases (66.7%), including 18 cases of AKI-1 (47.4%), 9 cases of AKI-2 (23.7%) and 11 cases of AKI-3 (28.9%). There was no significant difference in cerebral rSO2 between AKI group and non-AKI group (F=0.012, P>0.05), while the intestinal rSO2 and renal rSO2 in AKI group were significantly lower than those in non-AKI group (F=5.017 and 5.003, both P<0.05). There was no significant difference in brain rSO2 between children with or without AKI-2 and above (F=0.311, P>0.05), but the intestinal rSO2 and renal rSO2 in children with AKI-2 and above were lower than other children (F=6.431 and 14.139, both P<0.05). The area under ROC curve (AUC) of intestinal rSO2 3 h after surgery for predicting AKI was 0.823, and with intestinal rSO2 3 h after surgery <85%, the sensitivity and specificity were 66.7% and 89.5%, respectively. The AUC of renal rSO2 for the diagnosis of AKI at 31 h after surgery was 0.918, and with intestinal rSO2 31 h after surgery <84%, the sensitivity and specificity were 72.2% and 84.2%, respectively. The AUC of intestinal rSO23 h after surgery for the diagnosis of AKI-2 and above was 0.829, and with intestinal rSO2 3 h after surgery <84%, the sensitivity and specificity were 62.2% and 90.0%, respectively. The AUC of renal rSO2 for the diagnosis of AKI-2 and above was 0.826 at 34 h postoperatively, and with intestinal rSO2 34 h after surgery <71%, the sensitivity and specificity were 91.9% and 55.0%, respectively. Conclusion: The monitoring of intestinal and renal rSO2 can predict the occurrence and severity of postoperative AKI in children with congenital heart disease after surgery.