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Updated: Jun 12, 2026

Pre-Chiasmatic, Single Injection of Autologous Blood to Induce Experimental Subarachnoid Hemorrhage in a Rat Model
Published on: June 18, 2021
Blood coagulation and fibrinolysis after experimental subarachnoid hemorrhage
Carl C Larsen1, Jacob Hansen-Schwartz, Jørn D Nielsen
1Department of Neurosurgery, Glostrup University Hospital, Glostrup, Denmark. larsen-cc@hotmail.com
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.
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