Changes in Automated Complete Blood Cell Count and Differential Leukocyte Count Results Induced by Storage of Blood at Room Temperature

Abstract Objective.—To delineate changes that occur in various parameters of automated complete blood cell count (CBC) and differential leukocyte count (differential) on prolonged storage of blood at room temperature. Design.—A CBC and an automated differential were performed on the Coulter Gen.S on 40 K3 (tripotassium ethylenediamine-tetraacetate) EDTA-anticoagulated blood specimens once daily, specimen volume permitting, for 3 to 7 days. Specimens were kept at room temperature throughout the study. The results were tabulated using a personal computer with Excel software. Percent change or absolute difference from the initial value for each parameter for each subsequent day of the study period was calculated. Results.—Among the CBC parameters, hemoglobin, red blood cell count, and mean corpuscular hemoglobin were stable for the duration of the study (7 days), white blood cell count was stable for at least 3 days (up to 7 days, if the count was within or above the normal range), and platelet count was sta...