Methods: The Score for Neonatal Acute Physiology (SNAP) measures illness severity and is highly predictive of mortality. Perinatal events might explain inter-NICU differences in admission SNAP. We prospectively abstracted 583 inborn babies <1500g in six NICUs and compared admission risk profiles by NICU using χ2 and ANOVA. Linear regression identified perinatal factors affecting SNAP and if these explained differences between NICUs.

Results: There were no differences among NICUs in gender, prenatal care or growth restriction. We did find significant differences in birth weight (BW), multiple birth, maternal hypertension (HTN), maternal steroids, C-section, low Apgar and hypothermia (table, all p<.01). Many of these same risk factors affected admission illness severity (HTN, steroids lowered SNAP; lower BW and Apgar raised SNAP; all p<.01). Adjusting only for maternal-fetal risks (BW, multiples, HTN) but not for perinatal stabilization (steroids, C-section, low Apgars, low temp), one NICU had unexplained higher admission severity (Site U* p<.01).

Table 1
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Conclusions: There are significant differences between NICUs in perinatal risk factors that affect admission severity. Variations in effectiveness of perinatal stabilization may further explain inter-NICU differences in admission severity.