Blood coagulation and fibrinolysis after experimental subarachnoid hemorrhage.

Abstract

BACKGROUND: Aneurysmal rebleeding poses a serious risk in patients with subarachnoid hemorrhage (SAH). Studies have shown that antifibrinolytic therapy with tranexamic acid has a dramatic effect on the rate of rebleeding. Therefore, changes in the fibrinolytic system could be hypothesized. METHODS: We have used an experimental SAH rat model to demonstrate serial changes in the haemostatic system as evaluated by Thromboelastography (TEG). RESULTS: In the SAH group, a shorter reaction time (R-time) and higher maximum amplitude (MA) were observed. In the saline group, only a shorter R-time was observed. CONCLUSIONS: The study has shown that a hypercoagulable state is present immediately after experimental SAH is induced as determined by TEG. The reduction in R-time and rise in MA observed in the SAH group indicate that blood in the subarachnoid space is necessary to accomplish a full systemic coagulation response. This abnormality in coagulation profile seems to be a response to the acute traumatic event caused by induction of SAH.