Thromboelastography (TEG) analysis was used to determine if differences exist between venous and arterial samples in anesthetized swine, using identical sampling techniques for each of the samples. We hypothesized that TEG parameters would not differ between native whole blood venous and arterial samples. Thirty male Landrace swines were included in the study. Both the femoral artery and vein were catheterized using standard cut-down techniques and with identically sized catheters to rule out any catheter size effects on the results. Standard TEG parameters for native whole venous and arterial blood samples (r, K, α, MA, G, and coagulation index) were measured or calculated, and t-test or Mann–Whitney rank-sum test used for comparison when appropriate. Significant differences were detected for r (venous < arterial), K (venous < arterial), α (venous > arterial), and coagulation index (venous > arterial) TEG parameters. No significant differences were measured for MA or G. These differences are important, especially when temporal changes in TEG are utilized to monitor patient stability and fluid therapy protocols using trends in coagulation properties. Taken together, these results suggest that clots are more likely to form at a faster rate in venous samples compared to arterial samples, but the overall clot strength does not differ. Therefore, if TEG analysis is being used to monitor coagulation profiles in a patient, care should be taken to use the same site and technique if results are to be used for comparative purposes.
aUniversity of Calgary, Faculty of Veterinary Medicine, Calgary,
bCanadian Forces Health Services, Defence Research and Development Canada-Suffield, Medicine Hat, Alberta, Canada
*Clinton J. Doering and Catherine R. Wagg contributed equally to this study.
Correspondence to Catherine R. Wagg, Faculty of Veterinary Medicine, TRW 2D01, 3280 Hospital Dr NW, Calgary, AB T2N 4Z6, CanadaTel: +403 210 3925; e-mail: firstname.lastname@example.org
Received 1 February, 2013
Revised 31 May, 2013
Accepted 1 June, 2013