Objective. To compare the transfusion practices between two neonatal i
ntensive care units (NICUs) to assess the impact of local practice sty
les on the timing, number, and total volume of packed red cell transfu
sions in very low birth weight infants. To derive multivariate models
to describe practice and to identify potential areas for improvement i
n the future. Methodology. We reviewed phlebotomy losses and transfusi
on rates between two NICUs (A and B) for 270 consecutive admissions of
birth weight <1500 g. We stratified for birth weight and for illness
severity by the Score for Neonatal Acute Physiology (SNAP). Measures o
f short-term outcome were compared. We derived multivariate models to
describe and compare the practices in the two NICUs. Results. Patients
in NICU A had smaller phlebotomy losses than those in NICU B. A lower
percentage of the patients in NICU A (65% vs 87%) received transfusio
ns, but they tended to receive a greater total volume per kg per patie
nt (67 mL/kg vs 54.8 mL/kg). Transfusion timing differed between the N
ICUs; in NICU A only approximately one-half of their transfusions occu
rred in the first 2 weeks, whereas in NICU B almost 70% of the transfu
sions were given in this time period. Multivariate models showed that
phlebotomy losses were significantly related to lower gestational age
(GA) and higher SNAP. Hospitalization in NICU B resulted in 10.7 cc of
additional losses relative to NICU A for a comparable GA and illness
severity score. The volume of blood transfused per kilogram of body we
ight was a function of GA, SNAP, and hospital. Care practices in NICU
A added an additional 19 cc of transfused volume in the first 14 days
of life, and an additional 26 cc thereafter when adjusted for GA and S
NAP. These differences in phlebotomy and transfusion were not associat
ed with differences in the days of oxygen therapy or mechanical ventil
ation, the oxygen requirement at 28 days, the incidence of chronic lun
g disease, or the rate of growth by day 28. Conclusions. We identified
significant differences in phlebotomy and transfusion practices betwe
en two NICUs. We found no differences in short-term outcome, suggestin
g that the additional use of blood in one of the NICUs was discretiona
ry rather than necessary. Our multivariate models can be used to chara
cterize and quantify transfusion and phlebotomy practices. By predicti
ng which patients are likely to require multiple transfusions, clinici
ans can target patients for erythropoietin therapy and identify those
patients for whom donor exposure can be reduced by a unit of blood for
multiple use. The models may help in monitoring changes in practice a
s they occur.