title: Thrombin activatable fibrinolysis inhibitor as a bleeding predictor in liver transplantation: a pilot observational study.
abstract: OBJECTIVE
  To correlate the levels of thrombin activatable fibrinolysis inhibitor in the immediate postoperative period and at 24 hours postoperatively with the volume of intraoperative bleeding.
  
  
  METHODS
  Twenty-one patients allocated immediately before (elective or emergency) liver transplantation were analyzed. Blood samples were collected for thrombin activatable fibrinolysis inhibitor analysis at three different time points: immediately before liver transplantation (preoperative thrombin activatable fibrinolysis inhibitor), immediately after the surgical procedure (immediate postoperative thrombin activatable fibrinolysis inhibitor), and 24 hours after surgery (thrombin activatable fibrinolysis inhibitor 24 hours after surgery). The primary outcome of the study was to correlate the preoperative and immediate postoperative levels of thrombin activatable fibrinolysis inhibitor with intraoperative blood loss.
  
  
  RESULTS
  There was a correlation between the preoperative thrombin activatable fibrinolysis inhibitor levels and bleeding volume (ρ = -0.469; p = 0.05) but no correlation between the immediate postoperative thrombin activatable fibrinolysis inhibitor and bleeding volume (ρ = -0.062; p = 0.79). No variable included in the linear regression analysis (prehemoglobin, prefibrinogen and preoperative thrombin activatable fibrinolysis inhibitor) was a bleeding predictor. There was a similar trend in the variation between the levels of thrombin activatable fibrinolysis inhibitor at the three different time points and fibrinogen levels. Patients who died within 6 months (14.3%) showed decreased preoperative and immediate postoperative levels of thrombin activatable fibrinolysis compared with survivors (preoperative: 1.3 ± 0.15 versus 2.55 ± 0.53, p = 0.06; immediate postoperative: 1.2 ± 0.15 versus 2.5 ± 0.42, p = 0.007).
  
  
  CONCLUSIONS
  There was a moderate correlation between preoperative thrombin activatable fibrinolysis inhibitor and intraoperative bleeding in liver transplantation patients, although the predictive role of this variable independent of other variables remains uncertain. Preoperative and immediate postoperative thrombin activatable fibrinolysis inhibitor levels may have a role in the survival prognosis of this population; however, this possibility requires confirmation in further studies with larger sample sizes.
authors.affiliation: Programa de Pós-Graduação em Hepatologia, Universidade Federal de Ciências da Saúde, Porto Alegre, RS, Brazil.
authors.forename: Wagner Luis
authors.initials: WL
authors.lastname: Nedel
authors.affiliation: Irmandade Santa Casa de Misericórdia de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Edison Moraes
authors.initials: EM
authors.lastname: Rodrigues Filho
authors.affiliation: Programa de Pós-Graduação em Hepatologia, Universidade Federal de Ciências da Saúde, Porto Alegre, RS, Brazil.
authors.forename: Alessandro Comarú
authors.initials: AC
authors.lastname: Pasqualotto
mesh_terms: D000368:Aged; D016063:Blood Loss, Surgical; D025901:Carboxypeptidase B2 / Q000378:metabolism*; D005260:Female; D005340:Fibrinogen / Q000378:metabolism; D006801:Humans; D016014:Linear Models; D016031:Liver Transplantation / Q000379:methods* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011184:Postoperative Period; D057234:Preoperative Period; D013997:Time Factors
chemical_list: D005340:Fibrinogen; D025901:Carboxypeptidase B2