Preanalytical issues related to blood sample mixing

INTRODUCTION Homogeneity of sample achieved by adequate mixing of the blood sample is the key to the quality of analytical results. Immediate mixing of the sample upon blood collection insures that the anticoagulant in the specimen container has fully dissolved with the blood, thus maintaining not only the effective anticoagulant-to-blood ratio but also providing a specimen free from any blood clots. The process of mixing should be such as not to result in the alteration of the integrity of the sample, such as hemolysis, and thus affect the quality of results.