Systematic evaluation of evidence on veterinary viscoelastic testing part 2: Sample acquisition and handling.
OBJECTIVE
To examine systematically the evidence on sample acquisition and handling for the thrombo elastography (TEG) and rotational thromboelastometry (ROTEM) viscoelastic point of care instruments and to identify knowledge gaps.


METHODS
Six questions were considered, addressing sampling site, collection system, anticoagulant, collection procedure, and sample storage. Standardized, systematic evaluation of the literature was performed. Relevant articles were categorized according to level of evidence (LOE). Consensus was developed regarding conclusions for application of concepts to clinical practice.


METHODS
Academic and referral veterinary medical centers.


RESULTS
PubMed and CAB abstracts were searched. Eighteen papers were initially chosen; 5 of these papers applied to > 1 domain question. Three papers were used to address 2 questions each, and 2 papers were used to address 3 questions each. Most papers were judged LOE 3 (Good or Fair). Two of 5 papers were judged to be the same LOE each time they were used; 2 papers were judged to be LOE 3, Fair for 1 question and 3, Good for a second question; 1 paper used to address 3 questions was judged LOE 3, Good twice and 3, Fair once. Fourteen additional papers were evaluated post hoc during manuscript preparation.


CONCLUSIONS
Jugular venipuncture is recommended, but samples from IV catheters can be used. Consistent technique is important for serial sampling, and standardized sampling protocols are recommended for individual centers performing TEG/ROTEM. There is insufficient evidence to recommend use of a specific blood collection system, although use of evacuated blood tubes and 21-Ga or larger needles is suggested. Use of 3.2% buffered sodium citrate in a strict 1:9 ratio of citrate to blood is suggested. Suggested tube draw order is discard/serum, followed by citrate, EDTA, and then heparin. Samples should be held at room temperature for 30 minutes prior to analysis.
From the Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996.
Bente
B
Flatland
Amy M
AM
Koenigshof
Elizabeth A
EA
Rozanski
Robert
R
Goggs
Bo
B
Wiinberg
D000818:Animals; D001800:Blood Specimen Collection / Q000379:methods / Q000592:standards / Q000662:veterinary*; D002415:Cats / Q000097:blood; D004285:Dogs / Q000097:blood; D006736:Horses / Q000097:blood; D012015:Reference Standards; D013916:Thrombelastography / Q000295:instrumentation / Q000379:methods / Q000662:veterinary*; D014730:Veterinary Medicine / Q000592:standards*
cat; dog; thromboelastography; thromboelastometry