Reference values for rotational thromboelastometry (ROTEM) in clinically healthy cats.
OBJECTIVE
To establish reference intervals for rotational thromboelastometry (ROTEM) using feline blood.


METHODS
Prospective study.


METHODS
University teaching hospital.


METHODS
Twenty-three clinically healthy cats between 1 and 15 years.


METHODS
For each cat, whole blood was collected via jugular or medial saphenous venipuncture, and blood was placed into a serum tube, a tube containing potassium-EDTA, and tubes containing 3.2% sodium citrate. The tubes were maintained at 37°C for a maximum of 30 minutes before coagulation testing.


RESULTS
ROTEM tests included the EXTEM, INTEM, FIBTEM, and APTEM assays. In addition, prothrombin time, activated partial thromboplastin time, thrombin time, and fibrinogen concentration (Clauss method) were analyzed for each cat. Reference intervals for ROTEM were calculated using the 2.5-97.5thpercentile for each parameter, and correlation with the standard coagulation profile was performed. Compared to people, clinically healthy cats had similar values for the EXTEM and INTEM assays, but had lower plasma fibrinogen concentrations (0.9-2.2 g/L), resulting in weaker maximum clot firmness (MCF, 3-10 mm) in the FIBTEM test. In 18 cats, maximum lysis (ML) values in the APTEM test were higher than in the EXTEM test, which seems unlikely to have occurred in the presence of aprotinin. It is possible that the observed high maximum lysis values were due to clot retraction rather than true clot lysis. Further studies will be required to test this hypothesis.


CONCLUSIONS
Cats have a weaker clot in the FIBTEM test, but have a similar clot strength to human blood in the other ROTEM assays, which may be due to a stronger contribution of platelets compared to that found in people. In cats, careful interpretation of the results to diagnose hyperfibrinolysis is advised, especially with the APTEM test, until further data are available.
Section of Anesthesiology, Equine Department, Vetsuisse Faculty of the University of Zurich, Zurich, Switzerland.
Charlotte
C
Marly-Voquer
the Clinical Laboratory, Vetsuisse Faculty of the University of Zurich, Zurich, Switzerland.
Barbara
B
Riond
the Small Animal Department, Critical Care, Vetsuisse Faculty of the University of Zurich, Zurich, Switzerland.
Rahel
R
Jud Schefer
Section of Anesthesiology, Equine Department, Vetsuisse Faculty of the University of Zurich, Zurich, Switzerland.
Annette P N
AP
Kutter
D000818:Animals; D001777:Blood Coagulation / Q000502:physiology*; D001780:Blood Coagulation Tests / Q000379:methods / Q000662:veterinary*; D001792:Blood Platelets; D002415:Cats / Q000097:blood* / Q000502:physiology; D005260:Female; D005340:Fibrinogen; D006801:Humans; D010314:Partial Thromboplastin Time; D011446:Prospective Studies; D011517:Prothrombin Time; D012016:Reference Values; D013916:Thrombelastography / Q000379:methods / Q000662:veterinary*
D005340:Fibrinogen
clot retraction; fibrinogen; hyperfibrinolysis; viscoelastic coagulation assay