Out-of-hours versus in-hours delivery of antenatally diagnosed transposition of the great arteries: outcomes from a United Kingdom Tertiary Centre

Objective To study the impact of out-of-hours delivery on outcome for neonates with antenatally diagnosed transposition of the great arteries. Setting Tertiary paediatric cardiology centre (Yorkshire, United Kingdom), with co-located tertiary neonatal unit. Patients Neonates with antenatally diagnosed simple transposition of the great arteries delivered out-of-hours (Monday to Friday 17:00-08:00 and weekends) versus in-hours between 2015 and 2020. Outcome The primary outcome was survival to hospital discharge. Secondary outcomes included neurological morbidity, length of stay, and time to balloon atrial septostomy. Results Of 51 neonates, 38 (75%) were delivered out-of-hours. All neonates born in the tertiary centre survived to discharge. Time to balloon atrial septostomy was slightly longer for out-of-hours deliveries compared to in-hours (median 130 versus 93 mins, p = 0.33). Neurological morbidity occurred for nine (24%) patients in the out-of-hours group and one (8%) in-hours (OR 3.72, 95% CI: 0.42-32.71, p = 0.24). Length of stay was also similar (18.5 versus 17.3 days, p = 0.59). Antenatal diagnosis of a restrictive atrial septum was associated with a lower initial pH (7.03 versus 7.13; CI: 0.03-0.17, p = 0.01), longer length of stay (22.6 versus 17.3 days; CI: 0.37-10.17, p = 0.04), and increased neurological morbidity (44% versus 14%; OR 4.80, CI 1.00-23.15, p = 0.05). A further three neonates were delivered in surrounding hospitals, with a mortality of 67% (versus 0 in tertiary centre; OR 172, CI 5-5371, p = 0.003). Conclusion Neonates with antenatally diagnosed transposition of the great arteries have similar outcomes when delivered out-of-hours versus in-hours. Antenatal diagnosis of restrictive atrial septum is a significant predictor of worse outcomes. In our region, delivery outside the tertiary cardiac centre had a significantly higher risk of mortality.