Process and Outcome Measures for Infants Born Moderate and Late Preterm in Tertiary Canadian Neonatal Intensive Care Units.

OBJECTIVE: To describe the prevalence of and between-center variations in care practices and clinical outcomes of moderate and late preterm infants (MLPIs) admitted to tertiary Canadian neonatal intensive care units (NICUs). STUDY DESIGN: This was a retrospective cohort study including infants born at 320/7 through 366/7 weeks of gestation and admitted to 25 NICUs participating in the Canadian Neonatal Network between 2015 and 2020. Patient characteristics, process measures represented by care practices, and outcome measures represented by clinical in-hospital and discharge outcomes were reported by gestational age weeks. NICUs were compared using indirect standardization after adjustment for patient characteristics. RESULTS: Among 25 669 infants (17% of MLPIs born in Canada during the study period) included, 45% received deferred cord clamping, 7% had admission hypothermia, 47% received noninvasive respiratory support, 11% received mechanical ventilation, 8% received surfactant, 40% received antibiotics in the first 3 days, 4% did not receive feeding in the first 2 days, and 77% had vascular access. Mortality, early-onset sepsis, late-onset sepsis, or necrotizing enterocolitis occurred in <1% of the study cohort. Median (IQR) length of stay was 14 (9-21) days among infants discharged home from the admission hospital and 5 (3-9) days among infants transferred to community hospitals. Among infants discharged home, 33% were discharged on exclusive breastmilk and 75% on any breastmilk. There were significant variations between NICUs in all process and outcome measures. CONCLUSIONS: Care practices and outcomes of MLPIs varied significantly between Canadian NICUs. Standardization of process and outcome quality measures for this population will enable benchmarking and research, facilitating systemwide improvements.

Spontaneous resolution of post-hemorrhagic ventricular dilatation in preterm newborns and neurodevelopment.

BACKGROUND: We investigated the temporal evolution of post-hemorrhagic ventricular dilatation (PHVD) and compared neurodevelopmental impairments (NDI) in newborns with (Group 1) spontaneous resolution of PHVD, (Group 2) persistent PHVD without neurosurgical intervention, and (Group 3) progressive PHVD receiving neurosurgical intervention. METHODS: A multicenter retrospective cohort study of newborns born at ≤34 weeks with PHVD (ventricular index [VI] >97th centile for gestational age and anterior horn width [AHW] >6 mm) from 2012 to 2020. Severe NDI was defined as global developmental delay or cerebral palsy GMFCS III-V at 18 months. RESULTS: Of 88 survivors with PHVD, 39% had a spontaneous resolution, 17% had persistent PHVD without intervention, and 44% had progressive PHVD receiving intervention. The median time between PHVD diagnosis and spontaneous resolution was 14.0 days (IQR 6.8-32.3) and between PHVD diagnosis and first neurosurgical intervention was 12.0 days (IQR 7.0-22.0). Group 1 had smaller median maximal VI (1.8, 3.4, 11.1 mm above p97; p < 0.001) and AHW (7.2, 10.8, 20.3 mm; p < 0.001) than Groups 2 and 3. Neurodevelopmental outcome data were available for 82% of survivors. Group 1 had reduced severe NDI compared to Group 3 (15% vs 66%; p < 0.001). CONCLUSION: Newborns with PHVD without spontaneous resolution are at higher risk for impairments despite neurosurgical interventions, which may be due to larger ventricular dilatation. IMPACT: The natural evolution of post-hemorrhagic ventricular dilatation (PHVD) and developmental implications of spontaneous resolution are not well established. In this study, approximately one in three newborns with PHVD experienced spontaneous resolution and this subset of newborns had reduced rates of neurodevelopmental impairments. More prominent ventricular dilatation was associated with reduced rates of spontaneous resolution and increased rates of severe neurodevelopmental impairment among newborns with PHVD. Understanding clinically relevant time points in the evolution of PHVD and predictors of spontaneous resolution may help inform the discussion around the optimal timing for intervention and allow for more precise prognostication in this population.

Neonatal intensive care unit occupancy rate and probability of discharge of very preterm infants.

OBJECTIVE: To assess the association of NICU occupancy with probability of discharge and length of stay (LOS) among infants born <33 weeks gestational age (GA). STUDY DESIGN: Retrospective study of 3388 infants born 23-32 weeks GA, admitted to five Level 3/4 NICUs (2014-2018) and discharged alive. Standardized ratios of observed-to-expected number of discharges were calculated for each quintile of unit occupancy. Multivariable linear regression models were used to assess the association between occupancy and LOS. RESULTS: At the lowest unit occupancy quintiles (Q1 and Q2), infants were 12% and 11% less likely to be discharged compared to the expected number. At the highest unit occupancy quintile (Q5), infants were 20% more likely to be discharged. Highest occupancy (Q5) was also associated with a 4.7-day (95% CI 1.7, 7.7) reduction in LOS compared Q1. CONCLUSION: NICU occupancy was associated with likelihood of discharge and LOS among infants born <33 weeks GA.

The association between BMI trajectories and bronchopulmonary dysplasia among very preterm infants.

OBJECTIVE: To investigate the association between change in body mass index (BMI) from birth to 36 weeks gestation (ΔBMI) and bronchopulmonary dysplasia (BPD) among infants born <30 weeks gestation. METHODS: This was a multicenter retrospective cohort study (2015-2018) of infants born <30 weeks gestation and alive at ≥34 weeks corrected. Main exposure was a change in BMI z score from birth to 36 weeks corrected age grouped into quartiles of change. Association between ΔBMI z scores and BPD was assessed using generalized linear mixed models. RESULTS: Among 772 included infants, 51% developed BPD. From birth to 36 weeks CGA, the weight z score of infants with BPD decreased less than for BPD-free infants, despite a greater decrease in length z score and similar caloric intake resulting in increases in BMI z score (median [IQR], 0.16 [-0.64; 1.03] vs -0.29 [-1.03; 0.49]; P < 0.01). In the adjusted analysis, higher ΔBMI z score quartiles were associated with higher odds of BPD (Q3 vs Q2, AOR [95% CI], 2.02 [1.23; 3.31] and Q4 vs Q2, AOR [95% CI], 2.00 [1.20; 3.34]). CONCLUSION: Among preterm infants, an increase in BMI z score from birth to 36 weeks corrected is associated with higher odds of BPD. IMPACT: Preterm infants with evolving lung disease often experience disproportionate growth in the neonatal period. In this multicenter cohort study, increases in BMI z score from birth to 36 weeks CGA were associated with higher odds of BPD. Despite similar caloric intake, infants with BPD had a higher weight- but lower length-for-age, resulting in higher BMI z score compared to BPD-free infants. This suggests that infants with evolving BPD may require different growth and nutritional targets compared to BPD-free infants.