Cumulative effect of evidence-based practices on outcomes of preterm infants born at <29 weeks gestational age.

BACKGROUND: Extremely preterm infants born at <29 weeks' gestational age are at high risk of death or severe neurological injury. Several individual evidence-based practices have been associated with neuroprotection. OBJECTIVE: The objective of the study was to investigate the cumulative effect of 4 evidence-based practices and their association with death and/or severe neurological injury among infants born at <29 weeks' gestational age. STUDY DESIGN: Observational study of infants born at 230-286 weeks gestational age admitted to neonatal intensive care units participating in the Canadian Neonatal Network from 2015 through 2017. We evaluated 4 practices: antenatal corticosteroids, antenatal MgSO4 for neuroprotection, deferred cord clamping >= 30 seconds, and normothermia on admission. The effect of exposure to 1, 2, 3, and all 4 evidence-based practices compared with none on death and/or severe neurological injury was assessed using multivariable logistic regression models adjusted for patient characteristics. RESULTS: Rate of death and/or severe neurological injury was 20% (873 of 4297) and varied based on exposure to evidence-based practices: none, 34% (54 of 157); 1, 27% (171 of 626); 2, 20% (295 of 1448); 3, 18% (263 of 1448); and all 4, 14% (90 of 618). Significantly lower odds of death and/or severe neurological injury were observed with exposure to antenatal corticosteroids (adjusted odds ratio, 0.52, 95% confidence interval, 0.40-0.69) and deferred cord clamping (adjusted odds ratio, 0.81, 95% confidence interval, 0.68-0.96) but not MgSO4 (adjusted odds ratio, 0.88, 95% confidence interval, 0.72-1.08) or normothermia (adjusted odds ratio, 0.96, 95% confidence interval, 0.79-1.16). Infants exposed to >= 2 evidence-based practices had significantly lower odds of death and/or severe neurological injury than those exposed to no evidence-based practices (adjusted odds ratio, 0.61, 95% confidence interval, 0.43-0.88). CONCLUSION: Among infants born at <29 weeks' gestational age, exposure to at least 2 of the evidence-based practices assessed was associated with decreased odds of death and/or severe neurological injury.