Factors associated with rebleeding after coil embolization in patients with aneurysmal subarachnoid hemorrhage

OBJECTIVE: Aneurysmal subarachnoid hemorrhage (aSAH) has a high mortality rate, and hemorrhage amounts and perioperative rebleeding importantly determines prognosis. However, despite adequate treatment, prognosis is poor in many ruptured aneurysm cases. In this study, we identified and evaluated factors related to perioperative rebleeding in patients with aSAH. METHODS: The medical and surgical records of 166 patients that underwent endovascular embolization for a ruptured cerebral aneurysm at a single institution from 2014 to 2016 were retrospectively analyzed to identify risk factors of rebleeding. All patients were examined for risk factors and evaluated for increased hemorrhage by brain computed tomography at 3 days after surgery. RESULTS: This series included 54 men (32.5%) and 112 women (67.5%) of mean age 58.3±14.3 years. After procedures, 26 patients (15.7%) experienced rebleeding, and 1 of these (0.6%) experienced an intraoperative aneurysmal rupture. External ventricular drainage (EVD) (odds ratio [OR] 5.389, [95% confidence interval (CI) 1.171- 24.801]) and modified Fisher grade (OR 2.037, [95% CI 1.077-3.853]) were found to be independent risk factors of rebleeding, and perioperative rebleeding was strongly associated with patient outcomes (p＜0.001). Conclusions: We concluded the rebleeding risk after aSAH is greater in patients with large hemorrhage amounts and a high pre-operative modified Fisher grade, and thus, we caution neurosurgeons should take care in such cases.