The effectiveness of cooling conditions on temperature of canine EDTA whole blood samples

PeerJ

article

Karen M. Tobias¹  Leslie Serrano²  Xiaocun Sun³  Bente Flatland⁴ 

[1]Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee Institute of Agriculture

[2]College of Veterinary Medicine, University of Tennessee Institute of Agriculture

[3]Office of Information Technology, University of Tennessee–Knoxville

[4]Department of Biomedical and Diagnostic Sciences, University of Tennessee Institute of Agriculture

关键词: Preanalytic;    Sample storage;    Ice bath;    Blood;    Cooling;    Ice water bath;    Temperature;    Laboratory error;   

DOI  :  10.7717/peerj.2732

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Background Preanalytic factors such as time and temperature can have significant effects on laboratory test results. For example, ammonium concentration will increase 31% in blood samples stored at room temperature for 30 min before centrifugation. To reduce preanalytic error, blood samples may be placed in precooled tubes and chilled on ice or in ice water baths; however, the effectiveness of these modalities in cooling blood samples has not been formally evaluated. The purpose of this study was to evaluate the effectiveness of various cooling modalities on reducing temperature of EDTA whole blood samples. Methods Pooled samples of canine EDTA whole blood were divided into two aliquots. Saline was added to one aliquot to produce a packed cell volume (PCV) of 40% and to the second aliquot to produce a PCV of 20% (simulated anemia). Thirty samples from each aliquot were warmed to 37.7 °C and cooled in 2 ml allotments under one of three conditions: in ice, in ice after transfer to a precooled tube, or in an ice water bath. Temperature of each sample was recorded at one minute intervals for 15 min. Results Within treatment conditions, sample PCV had no significant effect on cooling. Cooling in ice water was significantly faster than cooling in ice only or transferring the sample to a precooled tube and cooling it on ice. Mean temperature of samples cooled in ice water was significantly lower at 15 min than mean temperatures of those cooled in ice, whether or not the tube was precooled. By 4 min, samples cooled in an ice water bath had reached mean temperatures less than 4 °C (refrigeration temperature), while samples cooled in other conditions remained above 4.0 °C for at least 11 min. For samples with a PCV of 40%, precooling the tube had no significant effect on rate of cooling on ice. For samples with a PCV of 20%, transfer to a precooled tube resulted in a significantly faster rate of cooling than direct placement of the warmed tube onto ice. Discussion Canine EDTA whole blood samples cool most rapidly and to a greater degree when placed in an ice-water bath rather than in ice. Samples stored on ice water can rapidly drop below normal refrigeration temperatures; this should be taken into consideration when using this cooling modality.

【 授权许可】

CC BY