Inclusion Criteria:  Patients admitted to the emergency department because of aneurysmal subarachnoid hemorrhage of poor grade (IV-V) according to the WFNS classification.  Exclusion Criteria:  Patients younger than 18 years old. Pregnant or breast-feeding patients. Aneurysmal subarachnoid hemorrhage due to trauma or vascular malformations other than cerebral aneurysms.