Summary
In a clinical setting, fresh frozen plasma (FFP) is transfused to diluted patients
with complicated surgery or trauma, as guided by prolonged conventional coagulation
times or low fibrinogen levels. However, the limited sensitivity of these coagulation
tests may restrict their use in measuring the effect of transfusion and hence predicting
the risk of perioperative bleeding. We used the more sensitive, calibrated automated
thrombogram (CAT) method to evaluate the result of therapeutic FFP transfusion to
51 patients with dilutional coagulopathy. Thrombin generation was measured in pre-
and post-transfusion plasma samples in the presence of either platelets or phospholipids.
For all patients, the transfusion led to higher plasma coagulation factor levels,
a shortened activated partial thromboplastin time, and a significant increase in thrombin
generation (peak height and endogenous thrombin potential). Interestingly, thrombin
generation parameters and fibrinogen levels were higher in posttransfusion plasmas
from patients who stopped bleeding (n=32) than for patients with ongoing bleeding
(n=19). Plasmas from 15 of the 19 patients with ongoing bleeding were markedly low
in either thrombin generation or fibrinogen level. We conclude that the thrombin generation
method detects improved haemostatic activity after plasma transfusion. Furthermore,
the data suggest that thrombin generation and fibrinogen are independent determinants
of the risk of perioperative bleeding in this patient group.
Keywords
Bleeding - dilutional coagulopathy - fibrinogen - platelets - thrombin generation
