Variations in early and intermediate neonatal outcomes for inborn infants admitted to a Canadian NICU and born of hypertensive pregnancies.

OBJECTIVE

To determine whether neonatal intensive care unit (NICU) outcomes vary by centre for inborn neonates of hypertensive pregnancies and, if so, whether that variation might be related to between-centre variations in obstetric practice.

METHODS

The study comprised a prospective cohort of 13 505 singleton neonates admitted to 17 Canadian NICUs. Adjusting for potential confounders, we used multivariate regression to analyze the relation between centre of delivery and 6 dependent variables: (1) Apgar score < 7 at 5 minutes; (2) Score of Neonatal Acute Physiology-II (SNAP-II) score > or = 10; (3) neonatal death; (4) neonatal death or morbidity (owing to bronchopulmonary dysplasia [BPD], intraventricular hemorrhage [IVH], necrotizing enterocolitis [NEC], persistent ductus arteriosus [PDA], or periventricular leukomalacia [PVL]); (5) BPD alone; and (6) major neonatal morbidity (that is, at least one of IVH, PVL, NEC, or PDA). NICU practices known to influence these outcomes were included in the modelling for neonatal death and neonatal morbidity. In a sensitivity analysis for practice variation, antenatal steroid exposure was both included and excluded in each regression.

RESULTS

For 5 of the 6 dependent variables, we identified between-centre variation that was not explained solely by variation in antenatal corticosteroid use. Adjusted odds ratios varied from 0.11 to 5.6 (the reference centre was the median rate of the adverse outcome).

CONCLUSIONS

In the pregnancy hypertension setting, between-centre variations in practice are associated with variations in neonatal physiology and survival. For infants admitted to NICU, the obstetric management of hypertensive pregnancies appears to have an effect on both short- and medium-term neonatal outcomes, even after correction for NICU management.