Relationship Between Postoperative Cerebral Oxygen Saturation And Clinical Outcomes After Congenital Heart Surgery

Objective:To explore the correlation between postoperative（PO）cerebral oxygen saturation（SctO₂）and clinical outcome in pediatric patients after congenital heart surgery.Methods:A prospective cohort study was conducted in 79 patients who underwent congenital heart surgery（CHD）with cardiopulmonary bypass and then admitted to intensive care unit（ICU）from December 2016 to December 2017 in Children’s Hospital of Chongqing Medical University.The PO SctO₂ within the first 24 hours was measured consecutively by near-infrared spectroscopy（Fore-sight,P/N01-06-2030C,CASmed,USA）.The nadir of SctO₂（nSctO₂）（last more than 10 seconds）and the mean of SctO₂（mSctO₂）were collected and then respectively analyzed with the pediatric risk of mortality III（Prism-III）score of PO 24 hours,the maximum of vasoactive-inotropic score of PO 24 hours（VISmax）,the duration of mechanical ventilation,the length of ICU stay and the adverse outcome（AO）which included the duration of mechanical ventilation more than 7 days,peritoneal dialysis,cardio-pulmonary resuscitation or death.Receiver operating characteristic（ROC）analysis of PO SctO₂ and AO was also utilized to explore a possible cutoff point.Results:Both the nSctO₂ and mSctO₂ were significantly correlated with the Prism III score（r_s=-0.688,P=0.000;r_s=-0.660,P=0.000）,the VISmax（r_s=-0.431,P=0.000;r_s=-0.476,P=0.000）,the duration of mechanical ventilation（r_s=-0.520,P=0.000;r_s=-0.548,P=0.000）,and the length of ICU（r_s=-0.519,P=0.000;r_s=-0.559,P=0.000）,respectively.30 cases（37.97%）were divided into AO group,while the other 49 cases（62.03%）were divided into non-AO group.The nSctO₂ and mSctO₂ were both significantly lower in AO group than those in non-AO group[43.50%（32.00%-46.25%）vs.56.00%（48.50%-60.50%）,P=0.000]and[62.00%（58.95%-65.63%）vs.69.50%（64.75%-73.62%）,P=0.000].ROC analysis indicated cutoff point of 51.50%of nSct O₂ in the first 24 hours to predict AO（AUROC=0.822,P=0.000）,95%CI（0.728,0.916）,with a sensitivity of 90.00%and a specificity of 67.30%.Conclusion:Both the amplitude and duration of decreased Sct O₂ in the PO 24 hours were correlated with the poor clinical outcome.A nadir of SctO₂（last more than 10 seconds）of 51.50%in the PO 24 hours may potentially act as a predictive cutoff point.