Risk factors of mortality in neonates with congenital heart disease after cardiopulmonary bypass: a retrospective study in China

Objective: Increasing congenital heart disease (CHD) neonates receive cardiac surgery especially after two-child policy in China. This study was to investigate the risk factors for the mortality of CHD neonates after cardiopulmonary bypass (CPB). Methods: CHD neonates (n=123) undergoing CPB were prospectively enrolled. According to the early outcome, neonates were divided into survivor group and non-survivor group. The demographics and peri-operative factors were collected and compared between them. Variables with significant difference in univariate analysis were screened out by forward likelihood selection procedure, and included for multivariable logistic regression analysis. Results: A total of 23 neonatesdied after CPB. The overall in-hospital mortality was 18.70%. Univariate analysis indicated that the RACHS-1 score (P=0.029), time of CPB (P=0.003), incidence of cardiac arrest (CA) (P=0.005), proportion of neonates receiving extracorporeal membrane oxygenation (ECMO) (P=0.040) and lactate level (P=0.003) were significantly different between two groups. These 5 variables with significant difference in univariate analysis were screened out by forward likelihood selection procedure and multivariatelogistic regression analysis was performed. Results showed the odds ratio (OR) of death was increased by 1.009 for every unit increase in the time of CPB (OR: 1.009, P=0.046) and by 4.937 for CA present postoperatively (OR: 4.937, P=0.009). Conclusion: Long CPB and postoperative presence of CA were independent risk factors for mortality in neonates after CPB. Thus, clinicians should shorten the time of CPB and take measures to reduce CA, aiming to reduce the post-operative mortality.