Background and Objectives: Neonates with single ventricle congenital heart disease (SVCHD) are at high risk for mortality during the period of time between staged surgical palliations (S1P: Norwood with BTT shunt, Sano shunt or hybrid palliation with pulmonary artery bands and maintenance of ductal patency with prostaglandin or a PDA stent, and S2P: bidirectional Glenn).  During the interstage, patients are either discharged into a home monitoring program, or they remain hospitalized until S2P if they have significant risk factors such as tricuspid valve regurgitation or an oxygen requirement precluding discharge.  Our objective was to retrospectively apply NEONATE scores categorizing patients as high risk (a score >17) or low risk (a score ≤17) for interstage mortality or transplant established by Ahmed et al. to our home monitoring (safe at home: SAH) cohort and our in house cohort (safe in house: SIH) at different timepoints throughout their clinical course following S1P.  We assessed NEONATE scores and outcomes to determine if the scores could help predict survival to S2P, and risk for mortality or cardiac transplantation during the interstage and following S2P. Methods: We retrospectively reviewed 51 patients, 30 SAH and 21 SIH born between January 2017 until May 2021.

Results: The SAH cohort had a low median discharge score of 6 (low risk category).  Seven days post extubation, the SIH cohort had statistically significantly higher scores than the SAH cohort (median: 23 versus 9, p value <0.0001).  Median NEONATE scores calculated prior to CVICU transfer to the floor were the following: (SAH: 9 versus SIH: 17, p value: 0.05).  Pre-S2P or pre-transplant scores were statistically significantly higher in the SIH cohort (median 15 versus 6, p value: 0.0008).  Both the SAH and SIH cohorts had one interstage death. There was no statistically significant difference in interstage mortality between the two cohorts (p value: >0.9999).  Three additional SAH patients died: 1 following Glenn, 1 after Glenn followed by transplant, and 1 after Glenn followed by ventricular assistance device implantation. Sixty six percent of SAH patients (2/3) who died post S2P had high risk scores pre S2P, and the patient who died during the interstage had consistent high-risk scores.  In the SIH cohort, 8 additional patients died: 6 post Glenn (3 had high risk scores pre-S2P) and 2 post transplant (both had high risk scores pre-transplant).

Conclusion: The NEONATE score when applied prospectively to SAH and SIH SVCHD patients could be a helpful tool to guide clinicians with predicting interstage and potentially post Glenn risk of mortality or transplant, subsequently improving management and patient outcomes.