Graduation Year


Document Type




Degree Granting Department

Community and Family Health

Major Professor

Karen (Kay) Perrin, Ph.D.

Committee Member

Jeffrey Jensen, M.D.

Committee Member

Jeffrey D. Kromrey, Ph.D.

Committee Member

Charles S. Mahan, M.D.

Committee Member

Robert M. Nelson, M.D.


Infant death, Acuity, Nurse staffing, Adverse events, Obstetrical interventions


The purpose of this study was to investigate the time of admission to a Neonatal Intensive Care Unit (NICU) and its association with in-hospital mortality among a cohort of neonates at a regional perinatal center. Two different time points were considered: admissions on the weekend versus the weekday and admissions during the nighttime shift versus the day shift. The secondary purpose of the study was to investigate if registered nurse staffing affected this association between NICU admission day or admission time and in-hospital death.

Three separate databases were used which contained information on NICU admissions, hospital deliveries and nurse staffing. These databases were linked resulting in data for each individual mother-infant pair for each separate admission to the NICU. Readmissions to the NICU, NICU admissions which could not be linked with the delivery data, admissions from the Newborn Nursery and transfers from other hospitals were excluded from the study. The final study population consisted of 1,846 admissions from October 1, 2001 through December 31, 2006.

Weekend admissions were lower than weekday admissions (29.6% versus 70.4%) and nighttime admissions were lower than day admissions (43.2% versus 56.8%). Infants admitted at nighttime were more likely to be low birth weight, have lower Apgar scores and less likely to be delivered by cesarean section. Weekend admissions did not differ significantly from weekday admissions, except weekend admissions were more likely to be Black (33.6% versus 28.6%, p=.30).

After adjusting for infant's acuity and other covariates using multivariate logistic regression, the odds of dying on the weekend was not significantly different than weekday admissions (AOR=1.06, 95% CI=.653-1.721) and were not significantly different for nighttime admissions (AOR=1.14, 95% CI=.722-1.79). Nurse staffing was not a significant covariate. Covariates which were significant risk factors for death prior to discharge were non-Black race of the infant, Apgar score of less than 7 at five minutes, presence of a fetal anomaly, and use of ventilation during the stay. Infant's birth weight was a significant protective factor.