title: Reduced clot-stability during the first 6 hours after aneurysmal subarachnoid haemorrhage--a prospective case-control study.
abstract: BACKGROUND
  Early rebleeding is an important cause of death and disability following aneurysmal subarachnoid haemorrhage (SAH). Recent studies have shown that 50-90% of the rebleedings occurred within the first 6 hours after the primary bleeding. The mechanism leading to rebleeding remains to be established. In the present prospective case-control study we hypothesize that patients with SAH develop a coagulopathy characterized by reduced clot stability during the early period after the initial bleeding.
  
  
  METHODS
  Patients with aneurysmal SAH was studied with a dynamic clot lysis assay and markers of fibrinolysis and clot stabilizers in blood samples taken within and after 6 hours after onset of bleeding. Results were compared with blood samples from age and gender matched healthy controls.
  
  
  RESULTS
  36 patients were enrolled, 26 patients had blood samples collected within 6 hours after the initial bleeding whereas 10 patients had blood samples taken later than 6 hours after the initial bleeding. Patients demonstrated significantly reduced clot stability during the first 6 hours after initial bleeding. Fibrinolytic activity was increased during the first 6 hours along with the inhibitors of fibrinolysis whereas the modulators of fibrinolysis were reduced or inactivated.
  
  
  CONCLUSIONS
  During the first 6 hours after SAH patients exhibit reduced clot-stability. Probably a consequence of activated fibrinolysis in combination with reduced or inactivated factor XIII and thrombin-activable fibrinolysis inhibitor.
authors.affiliation: Department of Neurosurgery, Rigshospitalet, Blegdamsvej 9, DK-2100 Copenhagen, Denmark. larsen-cc@hotmail.com
authors.forename: Carl C
authors.initials: CC
authors.lastname: Larsen
authors.forename: Benny
authors.initials: B
authors.lastname: Sørensen
authors.forename: Jørn D
authors.initials: JD
authors.lastname: Nielsen
authors.forename: Jens
authors.initials: J
authors.lastname: Astrup
mesh_terms: D001777:Blood Coagulation / Q000502:physiology*; D016022:Case-Control Studies; D005176:Factor XIII / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013345:Subarachnoid Hemorrhage / Q000097:blood*
chemical_list: D005176:Factor XIII