**1. Introduction**

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating neurological condition and is associated with high morbidity and mortality. Poor-grade aSAH accounts for approximately 30% of all aSAH, and it is a severe subtype of aSAH. These patients more often present with acute hydrocephalus, severe intraventricular hemorrhage, microcirculatory disturbances, and even multi-organ failure after ictus [1, 2] . Traditionally, these patients are managed conservatively, and only those who show clinical improvement were selected for aggressive treatment [1, 3, 4]. However, aneurysm rebleeding occurs in patients with poor-grade aSAH, and about 50% of rebleeding is at the early stage after the hemorrhage [5]. Nowadays endovascular coiling, surgical clipping, and intensive neurocritical care have improved outcomes in patients

with poor-grade aSAH [6–11]. However, more than 60% of patients have unfavorable outcomes with severe disability [12]. The treatment decision-making is still challenging. There are limited data on high-level clinical trials focusing on the treatment of poor-grade aSAH. Therefore, we review the current therapeutical management and prognosis of poor-grade aSAH.
