title: Comparison of porcine and human coagulation by thrombelastometry.
abstract: BACKGROUND
  Although the pig is a standard model for the evaluation of various diseases in humans, including coagulopathy, it is not clear whether results in animals can be extrapolated to man.
  
  
  METHODS
  In 75 anesthetized pigs, we assessed reagent-supported thrombelastometry (ExTEM®), platelet-blocked thrombelastometry (FibTEM®), and aprotinin thrombelastometry (ApTEM®). Results were compared to values from 13 anesthetized humans. RESULTS (MEDIAN, 95% CI): ExTEM®: While clot strength was comparable in pigs (66 mm, 65-67 mm) and in humans (64 mm, 60-68 mm; NS), clotting time in animals was longer (pigs 64 s, 62-66 s; humans 55 s, 49-71 s; P<0.05) and clot formation time shorter (pigs 52 s, 49-54 s; humans 83 s, 67-98 s, P<0.001). The clot lysis index at 30 minutes was lower in animals (96.9%, 95.1-97.3%) than in humans (99.5%, 98.6-99.9%; P<0.001). ApTEM® showed no hyperfibrinolysis in animals. Modification of the anesthesia protocol in animals resulted in significant ExTEM® changes. FibTEM®: Complete platelet inhibition yielded significantly higher platelet contribution to clot strength in pigs (79%, 76-81%) than in humans (73%, 71-77%; P<0.05), whereas fibrinogen contribution to clot strength was higher in humans (27%, 24-29%) than in animals (21%, 19-24%; P<0.05).
  
  
  CONCLUSIONS
  Maximum clot firmness is comparable in human and porcine blood. However, clot lysis, platelet and fibrinogen contribution to clot strength, as well as initiation and propagation of clotting, are considerably different between pigs and humans. In addition, anesthesic drugs seem to influence thrombelastometry in animals. Accordingly, coagulation abnormalities in pigs subjected to diseases may not necessarily represent the coagulation profile in sick patients.
authors.affiliation: Department of Pediatric Surgery, Inselspital, Bern University Hospital and University of Bern, Switzerland.
authors.forename: Ulf
authors.initials: U
authors.lastname: Kessler
authors.forename: Tamar
authors.initials: T
authors.lastname: Grau
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Gronchi
authors.forename: Steffen
authors.initials: S
authors.lastname: Berger
authors.forename: Sebastian
authors.initials: S
authors.lastname: Brandt
authors.forename: Hendrik
authors.initials: H
authors.lastname: Bracht
authors.forename: Carlo
authors.initials: C
authors.lastname: Marcucci
authors.forename: Zacharias
authors.initials: Z
authors.lastname: Zachariou
authors.forename: Stephan M
authors.initials: SM
authors.lastname: Jakob
mesh_terms: D000777:Anesthetics / Q000494:pharmacology; D000818:Animals; D001777:Blood Coagulation; D001780:Blood Coagulation Tests / Q000379:methods; D001792:Blood Platelets; D005340:Fibrinogen; D005342:Fibrinolysis; D006801:Humans; D007202:Indicators and Reagents; D034421:Sus scrofa; D013916:Thrombelastography / Q000379:methods*
chemical_list: D000777:Anesthetics; D007202:Indicators and Reagents; D005340:Fibrinogen