Abstract
Primary Subject area
Neonatal-Perinatal Medicine
Background
In a health care system with limited resources, hospital organizational factors such as unit occupancy and nurse-to-patient ratios may contribute to patient outcomes.
Objectives
We aimed to assess the association of NICU occupancy and nurse staffing with outcomes of very preterm infants born < 33 weeks gestational age (GA).
Design/Methods
This was a multicenter retrospective cohort study of infants born 23-32 weeks GA without major congenital anomaly, admitted within 2 days after birth to one of four Level 3 NICUs in Quebec, Canada (2015-2018). For each 8 h shift, data on unit occupancy were obtained from a central provincial database (SiteNeo) and linked to the hospital nursing hours database (Logibec). Unit occupancy rates and nursing provision ratios (nursing hours/recommended nursing hours based on patient dependency categories) were pooled for the first shift, 24 h, and 7 days of admission for each infant. Patient data were obtained from the Canadian Neonatal Network database. Primary outcome was mortality and/or morbidity (severe neurological injury, bronchopulmonary dysplasia, necrotizing enterocolitis, and late-onset sepsis, severe retinopathy of prematurity). Adjusted odds ratios (AOR) for association of exposure with outcomes were estimated using generalized linear mixed models with a random effect for center, while adjusting for confounders (gestational age, small for gestational age, sex, outborn, Score for Neonatal Acute Physiology version 2, mode of delivery, and the other organizational variables).
Results
Among 1870 infants included in analyses, 796 (43%) had mortality/morbidity. Median occupancy was 89% (IQR 82-94) and median nursing provision was 1.13 (IQR 0.97-1.37). Overall higher NICU occupancy on shift of admission, first 24 h, and 7 days were associated with higher odds of mortality/morbidity (Figure 1) but nursing provision was not (Figure 2). Subgroup analysis by GA (< 29 and 29-32 weeks) yielded similar results (not shown). Generalized linear mixed model analyses showed that a 5% reduction in occupancy in the first 24 h of admission was associated with a 6% reduction in mortality/morbidity.
Conclusion
NICU occupancy is associated with mortality/morbidity among very preterm infants and may reflect lack of adequate resources in periods of high activity. Interventions aimed at reducing occupancy and maintaining adequate resources need to be considered as strategies to improve patient outcomes.
Adverse effects of small for gestational age differ by gestational week among very preterm infants
