Metabolic secondary systemic insults among newborns with encephalopathy and their outcome: a descriptive single-center cohort study

Purpose: To evaluate the frequency of metabolic secondary systemic insults (mSSI) and its association with mortality in newborns with encephalopathy. Methods This single-center observational study of neonatal encephalopathy (NE) in patients in 2018–2020 defined mSSI as at least one abnormal finding for any of glucose, sodium, and/or carbon dioxide from routine blood samples during the first 3 days of life. Thresholds were hypoglycemia, <2 mmol/L; hyperglycemia, >10 mmol/L; hyponatremia, <130 mmol/L; hypernatremia, >150 mmol/L; hypocapnia, <30 mmHg; and hypercapnia, >70 mmHg. The cumulative number of mSSIs was the sum of these six types. The primary outcome was in-hospital mortality. Results Among the 109 newborns included, 22% presented no mSSI, 35% one type, 28% two, 11% three, and 4% four. The cumulative number of mSSIs was significantly ( p <0.01) associated with the 5-minute Apgar score and the severity of hypoxic-ischemic encephalopathy; 8.3% of infants with no mSSI, 24.3% with one, 42.3% with two, and 53.8% with three or more mSSIs were graded Sarnat III ( p <0.01). Mortality was significantly ( p = 0.009) associated with the cumulative number of mSSI types: 0/24 patients with no mSSI, 2/38 (5.3%) patients with one type, 3/31 (9.7%) with two types, and 5/16 (31.3%) with three or more types. Conclusion: Among the neonates hospitalized for NE, mSSI concerned 80%. The cumulative number of mSSI types was significantly associated with mortality. Further studies are needed to evaluate the prognostic impact of controlling these mSSIs.