This manuscript provides a comprehensive review of intracranial aneurysms (IA), covering their prevalence, epidemiology, and pathogenesis, as well as the risk factors that contribute to aneurysm rupture. It examines the clinical presentation, diagnosis, and critical care management of aneurysmal subarachnoid hemorrhage (aSAH), emphasizing strategies to prevent early and delayed complications. The paper also explores the pathophysiology, classification, and modern understanding of vasospasm and delayed cerebral ischemia (DCI), highlighting recent advances in monitoring and therapeutic interventions aimed at reducing neurological damage and improving long-term outcomes after IA rupture.