Correlation Between Reoxygenation During CPB And Low Cardiac Output Syndrome Postoeration In Complete Repair Of TOF

Objective This study was designed to investigate the association between reoxygenation during CPB and low cardiac output syndrome in children with tetralogy of Fallot.Methods This is a single-center,retrospective clinical study.We analysis the data of the 495 children with TOF complete repair performed between June 2012 and December 2018 in our hospital.The primary inclusion criteria were children with tetralogy of Fallot who were younger than 18 years of age.The primary endpoint was postoperative Low cardiac output syndrome occurred within 3 days.Firstly,univariate analysis was used to investigate the important risk factors affecting postoperative LCOS.Multivariate logistic regression analysis was then used to investigate the independent risk factors affecting postoperative LCOS.The McGoon ratio was divided by 1.50,and patients were divided into two groups:McGoon ratio ?1.50 group and McGoon ratio<1.50 group.Logistic regression model was used to investigate the relationship between reoxygenation during CPB and postoperative LCOS in the subgroup.Results The incidence of LCOS was higher in the McGoon ratio<1.50 than in the McGoon ratio?1.50 group.The difference between the two groups was statistically significant(P=0.003).Preoperative low mean arterial pressure,right bundle branch block before surgery,high preoperative cardiac function grading NYHA(?-?)and postoperative pulmonary valve regurgitation were independent risk factors for postoperative LCOS.Before the baseline and clinical factors were adjusted,the risk of postoperative LCOS increased significantly with the increase in cardiopulmonary oxygen partial pressure in the McGoon ratio<1.50(OR 1.005,950%Cl[1.000,1.010]P=0.033).However,in the McGoon ratio ?1.50 group,the risk of postoperative LCOS did not increase significantly with the increase of reoxygenation during CPB(OR 1.000,95%Cl[0.995,1.005]P=0.999).After adjusting for baseline and clinical factors,the risk of postoperative LCOS was significantly increased in the McGoon<1.50 group with increasing reoxygenation during CPB(OR 1.005,95%Cl[1.000,1.010]P=0.039 In the McGoon?1.50 group,the risk of postoperative LCOS did not increase significantly with the increase of reoxygenation during CPB(OR 1.000,95%Cl[0.995,1.006]P=0.921).Conclusion The difference of McGoon ratio has a significant effect on the relationship between reoxygenation during CPB and postoperative LCOS in tetralogy of Fallot.The higher cardiopulmonary oxygen partial pressure in extracorporeal circulation significantly increased the McGoon ratio<1.50.The risk of developing LCOS in children.