An assessment of thromboelastometry to monitor blood coagulation and guide transfusion support in liver transplantation.
BACKGROUND
Rotation thromboelastometry (TEM) has been proposed as a convenient alternative to standard coagulation tests in guiding the treatment of coagulopathy during orthotopic liver transplantation (OLT). This study was aimed at assessing the value of TEM in monitoring blood coagulation and guide transfusion support in OLT.


METHODS
Standard coagulation and TEM (EXTEM and FIBTEM) tests were performed at four preestablished intraoperative time points in 236 OLTs and prospectively recorded in a dedicated database together with the main operative and transfusion data. Transfusion thresholds were based on standard coagulation tests. Spearman's rank correlation (ρ), linear regression, and receiver operating characteristic curves were used when appropriate.


RESULTS
EXTEM maximum clot firmness (MCF(EXTEM)) was the TEM variable that best correlated with the platelet (PLT) and fibrinogen levels (ρ = 0.62 and ρ = 0.69, respectively). MCF(FIBTEM) correlated with fibrinogen level (ρ = 0.70). EXTEM clot amplitude at 10 minutes (A10(EXTEM)) was a good linear predictor of MCF(EXTEM) (R(2) =0.93). The cutoff values that best predicted the transfusion threshold for PLTs and fibrinogen were A10(EXTEM) = 35 mm and A10(FIBTEM) = 8 mm. At these values, the negative and positive predictive accuracies of TEM to predict the transfusion thresholds were 95 and 27%, respectively.


CONCLUSIONS
A10(EXTEM) is an adequate TEM variable to guide therapeutic decisions during OLT. Patients with A10(EXTEM) of greater than 35 mm are unlikely to bleed because of coagulation deficiencies, but using A10(EXTEM) of not more than 35 mm as the sole transfusion criterion can lead to unnecessary utilization of PLTs and fibrinogen-rich products.
Hospital Clinic Barcelona, Barcelona, Spain. ablasi@clinic.ub.es
Annabel
A
Blasi
Joan
J
Beltran
Arturo
A
Pereira
Graciela
G
Martinez-Palli
Abiguei
A
Torrents
Jaume
J
Balust
Elizabeth
E
Zavala
Pilar
P
Taura
Juan-Carlos
JC
Garcia-Valdecasas
D000328:Adult; D001777:Blood Coagulation / Q000502:physiology*; D001780:Blood Coagulation Tests / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D001800:Blood Specimen Collection / Q000379:methods / Q000592:standards; D001803:Blood Transfusion / Q000706:statistics & numerical data*; D005260:Female; D005340:Fibrinogen / Q000032:analysis; D006801:Humans; D016031:Liver Transplantation / Q000009:adverse effects / Q000534:rehabilitation; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D010976:Platelet Count; D059039:Standard of Care; D013916:Thrombelastography / Q000379:methods / Q000706:statistics & numerical data*
D005340:Fibrinogen