title: Recombinant activated factor VII and prothrombin complex concentrates have different effects on bleeding and arterial thrombosis in the haemodiluted rabbit.
abstract: BACKGROUND
  Recombinant activated factor VII (rFVIIa) is indicated in bleeding patients when a life-threatening haemorrhage occurs. Prothrombin complex concentrates (PCCs) are also used for this indication in several countries, without any evidence-based rationale. Our objective was to compare the efficacy and safety of PCC and rFVIIa in a model of bleeding and thrombosis in haemodiluted rabbits.
  
  
  METHODS
  Forty-eight rabbits were randomly allocated into four groups: a control group and three treatment groups, in which animals were haemodiluted with hydroxyethyl starch 130/0.4 then administered either placebo, 160 µg kg(-1) rFVIIa, or 25 IU FIX kg(-1) PCC. The primary endpoint was hepatosplenic (HS) blood loss. Secondary endpoints were: (i) ear immersion bleeding time (IBT); (ii) thrombosis risk assessed by cyclic flow reductions (CFRs) of the carotid artery; and (iii) activated partial thromboplastin time (aPTT), and progress of thrombin activity.
  
  
  RESULTS
  Haemodilution increased HS blood loss by 80% from 8 g (5-16) (control group) to 14 g (8-45) (placebo group) (P<0.01). HS blood loss was not different in animals receiving either rFVIIa [10 g (7-22)] or PCC [15 g (4-33)] (P<0.05) compared with the placebo group. Ear IBT was reduced with both rFVIIa and PCC. CFRs disappeared after haemodilution and were not restored with any treatment. Although PCC nearly doubled the total amount of thrombin generated, no significant change in the total amount of thrombin was seen in animals treated with rFVIIa.
  
  
  CONCLUSIONS
  Neither rVIIa nor PCC reduced HS blood loss, whereas they both controlled the bleeding time, without increasing the thrombosis risk.
authors.affiliation: INSERM UMRS 765, Paris, France.
authors.forename: F
authors.initials: F
authors.lastname: Le Saché
authors.forename: B
authors.initials: B
authors.lastname: Le Bonniec
authors.forename: P
authors.initials: P
authors.lastname: Gaussem
authors.forename: B
authors.initials: B
authors.lastname: Dizier
authors.forename: M
authors.initials: M
authors.lastname: Tagzirt
authors.forename: A
authors.initials: A
authors.lastname: Godier
authors.forename: J
authors.initials: J
authors.lastname: Emmerich
authors.forename: C-M
authors.initials: CM
authors.lastname: Samama
mesh_terms: D000818:Animals; D001760:Bleeding Time; D001779:Blood Coagulation Factors / Q000627:therapeutic use*; D003029:Coagulants / Q000494:pharmacology*; D004195:Disease Models, Animal; D015942:Factor VIIa / Q000494:pharmacology*; D006438:Hemodilution; D006470:Hemorrhage / Q000188:drug therapy*; D006895:Hydroxyethyl Starch Derivatives / Q000008:administration & dosage; D008297:Male; D010314:Partial Thromboplastin Time; D011517:Prothrombin Time; D011817:Rabbits; D011994:Recombinant Proteins / Q000494:pharmacology; D013927:Thrombosis / Q000188:drug therapy*; D016896:Treatment Outcome
chemical_list: D001779:Blood Coagulation Factors; D003029:Coagulants; D006895:Hydroxyethyl Starch Derivatives; D011994:Recombinant Proteins; C025667:prothrombin complex concentrates; C103587:recombinant FVIIa; D015942:Factor VIIa