Background: There is increasing evidence for the role of inflammation in clinical outcome after subarachnoid hemorrhage (SAH). Specifically, the TNF-alfa(α) pathway seems to be relevant after SAH. Although the TNF-α main receptor, TNF-R1 is associated with aneurysm growth and rupture, its relation to prognosis is unknown. We sought to compare TNF-R1 levels in peripheral venous blood and arterial blood closer to...