The differential impact of delivery hospital on the outcomes of premature infants.
BACKGROUND
Because greater percentages of women deliver at hospitals without high-level NICUs, there is little information on the effect of delivery hospital on the outcomes of premature infants in the past 2 decades, or how these effects differ across states with different perinatal regionalization systems.


METHODS
A retrospective population-based cohort study was constructed of all hospital-based deliveries in Pennsylvania and California between 1995 and 2005 and Missouri between 1995 and 2003 with a gestational age between 23 and 37 weeks (N = 1328132). The effect of delivery at a high-level NICU on in-hospital death and 5 complications of premature birth was calculated by using an instrumental variables approach to control for measured and unmeasured differences between hospitals.


RESULTS
Infants who were delivered at a high-level NICU had significantly fewer in-hospital deaths in Pennsylvania (7.8 fewer deaths/1000 deliveries, 95% confidence interval [CI] 4.1-11.5), California (2.7 fewer deaths/1000 deliveries, 95% CI 0.9-4.5), and Missouri (12.6 fewer deaths/1000 deliveries, 95% CI 2.6-22.6). Deliveries at high-level NICUs had similar rates of most complications, with the exception of lower bronchopulmonary dysplasia rates at Missouri high-level NICUs (9.5 fewer cases/1000 deliveries, 95% CI 0.7-18.4) and higher infection rates at high-level NICUs in Pennsylvania and California. The association between delivery hospital, in-hospital mortality, and complications differed across the 3 states.


CONCLUSIONS
There is benefit to neonatal outcomes when high-risk infants are delivered at high-level NICUs that is larger than previously reported, although the effects differ between states, which may be attributable to different methods of regionalization.
The Children's Hospital of Philadelphia, Center for Outcomes Research, 3535 Market St, Suite 1029, Philadelphia, PA 19104, USA. lorch@email.chop.edu
Scott A
SA
Lorch
Michael
M
Baiocchi
Corinne E
CE
Ahlberg
Dylan S
DS
Small
D001997:Bronchopulmonary Dysplasia / Q000401:mortality; D002140:California; D002423:Cause of Death; D003428:Cross Infection / Q000401:mortality; D005260:Female; D017052:Hospital Mortality; D006785:Hospitals, University / Q000706:statistics & numerical data*; D006801:Humans; D052577:Infant, Extremely Low Birth Weight; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000401:mortality* / Q000628:therapy; D019102:Infant, Very Low Birth Weight; D007363:Intensive Care Units, Neonatal / Q000706:statistics & numerical data*; D008923:Missouri; D007752:Obstetric Labor, Premature / Q000517:prevention & control; D017063:Outcome Assessment, Health Care; D010414:Pennsylvania; D011247:Pregnancy; D012189:Retrospective Studies; D018570:Risk Assessment; D014600:Utilization Review