• Blood gas analysis;
  • preanalytical error;
  • sample storage

Background: The effect of storage temperature and time on blood gas and acid-base values has been investigated intensively in cattle and dogs; however, data are lacking in other species. Objective: The aim of our study was to evaluate changes in gas composition and acid-base values in venous blood stored at different temperatures and for different times in 4 domestic species in Italy. Methods: Blood samples from Comisana sheep (n=10), Maltese goats (n=10), Ragusana donkeys (n=10), and Thoroughbred horses (n=10) were analyzed after storage at 23°C (room temperature) for 15 minutes (group I), 23°C for 1 hour (group II), 37°C for 8 hours (group III), and 4°C for 24 hours (group IV). Results were analyzed using a 1-way repeated measures ANOVA. Results: In all species no statistically significant differences in pH values were present in samples stored at 4°C for 24 hours. This also was true for Pco2 in all species except the horse. Except for HCO3 concentration in the horse, significant changes in Po2, HCO3 concentration, base excess, and the standard bicarbonate concentration were observed for all species in samples stored at 4°C. In samples stored for only 1 hour at room temperature, significant changes in most analytes were detected. Conclusions: The results of this study underline the need for rapid assessment of acid-base samples, because any delay, even for 1 hour, may affect the results.