During the 4-year study period, 439 infants underwent neonatal cardiothoracic surgery. Characteristics of the cohort are listed in Table 1. Prenatal diagnosis was made in 294 (67%) infants. Median DOL of surgery was 7 days (IQR 5–9), and median length of hospital stay was 17 days (IQR 12–28). Postoperative mortality was 5% in the entire series.
Differences between the prenatal and postnatal diagnosis group are listed in Tables 2, 3. The prenatal diagnosis group had a lower mean GA (37.9 ± 2.1 vs. 38.6 ± 2.4 wk, p < 0.001) and BW (3.0 ± 0.6 vs. 3.1 ± 0.6 kg, p = 0.002) and were more likely to be born at our tertiary care center where the surgery was performed (OR 156.7; 95% CI 55.6–441.8, p < 0.001) compared with infants diagnosed after birth.
Cardiac Diagnosis Breakdown
The prenatal diagnosis group had higher surgical severity scores (p < 0.001) compared with the postnatal group in accordance with the higher prevalence of more severe forms of CHD among the prenatal group (Table 4). Infants with HLHS were more likely to be PREdx (OR 4.1; 95% CI 1.9–8.9), whereas infants with transposition of the great arteries (TGA) were less likely to have a prenatal diagnosis (OR 0.4; 95% CI 0.3–0.7). Infants with total anomalous pulmonary venous return (TAPVR) were also less likely to be diagnosed before birth (OR 0.02; 95% CI 0.0–0.1).
Prenatal diagnosis did not impact neonatal mortality. Independent factors associated with mortality are listed in Tables 5, 6. SV morphology (p < 0.001), surgical severity score (p = 0.002), postoperative open chest (p < 0.001), 1-min Apgar score (p = 0.05), and bypass time (p < 0.001) were significantly associated with mortality. Multivariate analysis demonstrated that postoperative open chest (OR 1.9; 95% CI, p = 0.12) was the only independent factor associated with mortality.
PREdx infants were less likely to receive preoperative mechanical ventilation (OR 0.6; 95% CI 0.4–0.9), antibiotics (OR 0.2; 95% CI 0.1–0.4), cardiac catheterization (OR 0.5; 95% CI 0.3–0.9), or emergent surgery (OR 0.2; 95% CI 0.1–0.5) compared with POSTdx infants (Tables 2, 3).
DOL of Surgery
Prenatal diagnosis did not impact DOL of surgery (median DOL of surgery 7 days [IQR 5–8] for prenatal diagnosis vs. 6 days [IQR 5–9] for postnatal diagnosis, p = 0.9). There was no difference in DOL of surgery among groups even when stratified by cardiac lesion (Table 7). Univariate associations between subject characteristics and DOL of surgery are listed in Table 8. Multivariate Cox-proportional hazard modeling demonstrated that the use of preoperative antibiotics (hazard ratio [HR] 0.7; 95% CI 0.6–0.9, p = 0.002) and additional fetal anomalies (HR 0.5; 95% CI 0.4–0.7, p < 0.001) were independently associated with a longer time to surgery when controlling for timing of diagnosis, prematurity, and low BW.
Univariate associations between subject characteristics and hospital LOS are listed in Table 9. The prenatal diagnosis group had longer median hospital LOS (20 [range 13–33] vs. 15 days [range 11–25], p = 0.001) than the postnatal diagnosis group. Multivariate Cox-proportional hazard modeling demonstrated that surgical severity score (HR 0.9; 95% CI 0.8–0.9, p < 0.001), other fetal anomalies (HR 0.7; 95% CI 0.5–0.9, p = 0.03), prematurity (HR 0.8; 95% CI 0.6–0.9, p = 0.036), and DOL of surgery (HR 0.9; 95% CI 09–1, p < 0.001) were independently associated with a longer hospital LOS when controlling for prenatal diagnosis and low BW. Prenatal diagnosis was not associated with hospital LOS in this multivariate model.
Prenatal Diagnosis Trends
Trends in prenatal diagnosis, DOL of surgery, and hospital LOS across the 4-year study period are listed in Table 10. Although there was no significant difference in the rate of prenatal diagnosis, median DOL of surgery and hospital LOS decreased significantly from 2004 to 2007.