Association of Early Postoperative Regional Oxygen Saturation Measures and Development of Necrotizing Enterocolitis in Neonates Following Cardiac Surgery

Necrotizing enterocolitis (NEC) is a relatively common complication in neonates with single ventricle physiology following heart surgery. Near-infrared spectroscopy (NIRS) is used to measure regional oxygen saturations in neonates in the postoperative period. We sought to investigate the association of somatic regional oxygen saturation (srSO₂) and cerebral regional oxygen saturation (crSO₂) in the early postoperative period and the subsequent development of NEC. We performed a retrospective cohort study of neonates who underwent cardiac surgery with cardiopulmonary bypass from October 2017 to September 2021 at the University of Virginia Children’s Hospital. Values of srSO₂ and crSO₂ were captured over the first 48 h following surgery. 166 neonates were included and the median age at time of surgery was 8 days. NEC was diagnosed in 18 neonates following heart surgery with a median interval from surgery to diagnosis of 7 days. Neonates with single ventricle physiology had lower average crSO₂ (62% vs 78%, p < 0.001), average srSO₂ (72% vs 86%, p < 0.001), average crSO₂ to srSO₂ ratio (0.874 vs 0.913, p < 0.001), and an increased average srSO₂–crSO₂ difference (10% vs 8%, p = 0.03). Adjusting for single ventricle physiology, lower average crSO₂ was associated with the development of definite NEC (modified Bell’s criteria stage IIa and higher) (OR = 0.86, 95% CI 0.78–0.96, p = 0.007). Lower crSO₂ values in the early postoperative period in neonates following cardiac surgery was associated with an increased risk in the subsequent development of NEC.