163 - Association Between Birth Weight Z-scores and Early Outcomes Following Truncus Arteriosus Repair.

Poster Number: 163
Publication Number: 163.101

Joseph J. Stephenson, Medical University of South Carolina College of Medicine, Charleston, SC, United States; Joseph J. Stephenson, Medical University of South Carolina College of Medicine, Charleston, SC, United States; Jessica Hook, MUSC Children's Hospital, Charleston, SC, United States; Jonathan Beall, Medical University of South Carolina, Charleston, SC, United States; Jason R. Buckley, MUSC Children's Hospital, Charleston, SC, United States; Shahryar M. Chowdhury, Medical University of South Carolina College of Medicine, Charleston, SC, United States; Martina Steurer, UCSF, San Francisco, CA, United States; Minoo N. Kavarana, Medical University of South Carolina College of Medicine, Charleston, SC, United States; John Costello, Medical University of South Carolina, Charleston, SC, United States; Dennis R. Delany, Johns Hopkins Children's Center, Baltimore, MD, United States

Background: Truncus arteriosus (TA) repair is associated with increased morbidity and mortality compared to many other congenital heart operations.

Objective: We sought to determine associations between fetal growth measured by birth weight and early outcomes in infants undergoing TA repair.

Design/Methods: We utilized the Pediatric Health Information System (PHIS) database to identify infants < 90 days old who underwent TA repair from 2004-2019. The primary exposure variable was birthweight Z-score, calculated based on gestational age at birth, sex and birth weight. The primary outcome was hospital mortality. Secondary outcomes were major complications, prolonged postop. length of hospital stay (LOS; > 30 days), and hospital readmission within one year. Subjects missing weight or gestational age at birth were excluded. Multivariable logistic regression models identified factors most strongly associated with adverse outcomes.

Results: 1,039 subjects were included. Median birthweight was 2,960gms; median gestational age at birth was 38 weeks; median birthweight Z-score was -0.47. Small for gestational age (SGA, corresponding to birth weight Z-score < -1.3) at birth was present in 21% of subjects. Hospital mortality occurred in 104 patients (10%). By univariate analysis, birth weight Z-scores were significantly lower in patients who experienced hospital mortality (median, -0.79 vs. -0.45; p = 0.006). SGA status (34% vs. 20%) was also significantly associated with increased hospital mortality by univariate analysis (p = 0.001) and with multivariable logistic regression (adjusted OR, 2.16; 95% CI, 1.37 – 3.41). Birthweight Z-scores and SGA status were not significantly associated with cardiac arrest, ECMO use, gastrostomy tube placement, tracheostomy, seizures, vocal cord paralysis, cardiac cath, infection, or hospital readmission. Prolonged postoperative LOS > 30 days occurred in 677 (65%) of subjects. Birth weight Z-scores were not significantly associated with prolonged postop. LOS (p = 0.82).Conclusion(s): In infants undergoing TA repair, lower birth weight z-scores and SGA status were significantly associated with increased mortality. These data are helpful for risk stratification. Future studies are warranted to identify causal factors for in-utero growth restriction.