Late-Term Gestation Is Associated With Improved Survival in Neonates With Congenital Heart Disease Following Postoperative Extracorporeal Life Support.

Abstract

Several population-based studies have shown that gestational age 39-40 weeks at birth is associated with superior outcomes in various pediatric settings. A high proportion of births for neonates with congenital heart disease occur before 39 weeks. We aimed to assess the influence of late-term gestation (39-40 wk) on survival in neonates requiring extracorporeal life support following surgery for congenital heart disease. Retrospective cohort study. The Royal Children's Hospital, Melbourne, Australia. Neonates requiring extracorporeal life support after cardiac surgery for congenital heart disease. From 2005 to 2014, 110 neonates (10.5% of neonates undergoing cardiac surgery) required extracorporeal life support after cardiac surgery. Indications were failure to separate from cardiopulmonary bypass in 40 (36%), extracorporeal cardiopulmonary resuscitation in 48 (44%), progressive low cardiac output in 15 (14%), and other reasons in seven (6%). Extracorporeal life support duration was 94 hours (interquartile range, 53-135), and 54 (49%) underwent single ventricle repair. Gestation at birth (n [%]) was as follows: less than 37 weeks, 19 (17%); 37-38 weeks, 38 (35%); 39-40 weeks, 50 (45%); 41 weeks or more, 3 (3%). By multivariable analysis (controlling for age, era of extracorporeal life support 2005-2009 vs 2010-2014, single ventricle status and acute renal failure), gestational age of 39-40 weeks was associated with the lowest odds for intensive care mortality: using less than 37 weeks as referent, the adjusted odds ratio (95% CI) for 37-38 weeks was 0.41 (0.12-1.33); for 39-40 weeks, 0.27 (0.08-0.84); and for 41 weeks or more, 1.06 (0.07-14.7). Similar association was also seen in a subcohort of study neonates (n = 66) who were commenced on extracorporeal life support after admission to intensive care: using less than 37 weeks as referent, the adjusted odds ratio (95% CI) for 37-38 weeks was 0.52 (0.10-2.80) and for 39-40 weeks, 0.15 (0.03-0.81). In this cohort of neonates requiring extracorporeal life support following cardiac surgery, 39-40 weeks of gestation at birth is associated with the best survival. The additional maturity gained by reaching a gestation of at least 39 weeks is likely to confer a survival advantage in this high-risk cohort.