Effects of storage time on chemistry results from canine whole blood, heparinized whole blood, serum and heparinized plasma.

The stability and storage characteristics of 24 blood constituents from dogs including nine enzymes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, lipase), 15 metabolites and minerals (albumin, bile acids, bilirubin, calcium, cholesterol, creatinine, fructosamine, glucose, magnesium, phosphate, potassium, protein, sodium, triglycerides, urea) were studied. Conditions studied included storing of nonanticoagulated and heparinized whole blood for 3 days (Part A), and storing of serum and heparinized plasma for 3 days (Part B). The storage temperature for both studies was +4 degrees C from day 0 to day 1, and +20 degrees C, from day 1 to day 2 and 3. Eight of 24 analytes showed no significant differences (p > 0.05) for three days in whole blood. However, the stability of all 24 analytes greatly improved by storing serum or heparinized plasma compared to nonanticoagulated or heparinized whole blood. In stored serum or heparinized plasma, 20 of 24 analytes showed no significant differences (p < 0.05) for 3 days. Nine of 24 analytes showed significant differences (p < 0.05) between serum and heparinized plasma, where CK, LDH, GGT, and potassium showed differences of possible clinical importance. This study strongly supports the practice of separating serum/plasma from clot/cells as promptly as possible to achieve improved stability for most analytes under test.