Expected erythrocyte, platelet and neutrophil values for term and preterm neonates.

Reference ranges are an important guide for properly interpreting the clinical laboratory studies obtained from newborn infants. To judge whether the data contained in a CBC (complete blood count) is "normal," a neonatologist cannot utilize the normal ranges of CBCs constructed by sampling healthy adult volunteers. This is because important developmental differences are present between CBC values from adults vs. neonates. Also, differences in gestational age and post-natal age of neonates result in a need to have separate sets of reference range values for each. Otherwise, much confusion can exist in determining whether the CBC values are lower or higher than they should be. We reasoned that reference ranges constructed from very large databases would be a valuable new tool for neonatologists. To create these, we used the electronic data of Intermountain Healthcare, a multihospital healthcare system in the western USA, focusing on each of the various CBC elements. This presentation will review this process and display some of the novel clinically useful findings resulting from these studies.