Association of nurse staffing and unit occupancy with mortality and morbidity among very preterm infants: a multicentre study

Abstract

ObjectiveIn a healthcare system with finite resources, hospital organisational factors may contribute to patient outcomes. We aimed to assess the association of nurse staffing and neonatal intensive care unit (NICU) occupancy with outcomes of preterm infants born <33 weeks’ gestation.DesignRetrospective cohort study.SettingFour level III NICUs.PatientsInfants born 23–32 weeks’ gestation 2015–2018.Main outcome measuresNursing provision ratios (nursing hours worked/recommended nursing hours based on patient acuity categories) and unit occupancy rates were averaged for the first shift, 24 hours and 7 days of admission of each infant. Primary outcome was mortality/morbidity (bronchopulmonary dysplasia, severe neurological injury, retinopathy of prematurity, necrotising enterocolitis and nosocomial infection). ORs for association of exposure with outcomes were estimated using generalised linear mixed models adjusted for confounders.ResultsAmong 1870 included infants, 823 (44%) had mortality/morbidity. Median nursing provision ratio was 1.03 (IQR 0.89–1.22) and median unit occupancy was 89% (IQR 82–94). In the first 24 hours of admission, higher nursing provision ratio was associated with lower odds of mortality/morbidity (OR 0.93, 95% CI 0.89 to 0.98), and higher unit occupancy was associated with higher odds of mortality/morbidity (OR 1.19, 95% CI 1.04 to 1.36). In causal mediation analysis, nursing provision ratios mediated 47% of the association between occupancy and outcomes.ConclusionsNICU 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.

The Association of NICU Strain with Neonatal Mortality and Morbidity

“…17 Future work may also consider examining the association of NICU strain with discharge and transfer, an association that has been described in prior work, and with birthing parent outcomes. 18,46 This study has limitations. First, this study reports the influence of NICU strain in a single state given the quantity of daily data.…”

Association of Shift-Level Organizational Factors with Nosocomial Infection in the Neonatal Intensive Care Unit

“…In one NICU-based multicenter study, NPR was not associated with morbidity/mortality after adjustment for occupancy, although this may have been the result of limited variation in their data (IQR 89-122 vs this study’s IQR of 85-125). 24 …”

“…Infants <33 weeks were included in this study, as they are high-risk patients with high resource use and compose a large proportion of patient-days in the NICU. 24 Exclusion criteria were moribund or palliative care upon admission; major congenital anomalies; length of stay <3 days (typically because of mortality); and diagnosis of early-onset sepsis (positive blood and/or cerebrospinal fluid culture drawn within the first 3 days after birth). The research ethics boards of each participating site approved this project.…”

“…Organization of work was similar between units, as previously described. 24 The majority of nurses worked 8-hour shifts. Each unit recorded patient acuity and occupancy 3 times per day (12:00 am , 8:00 am , and 4:00 pm ) in a provincial administrative database.…”