Abstract:Objective To investigate the effects of the duration and volume of cerebrospinal fluid drainage through the lumbar cistern on the occurrence of postoperative hydrocephalus in patients with aneurysmal subarachnoid hemorrhage (aSAH). Methods We retrospectively analyzed the clinical data of 97 patients with aSAH who had continuous cerebrospinal fluid drainage through the lumbar cistern after operation. They were divided into short-term group and long-term group by the duration of drainage, and into low-volume group and high-volume group by the volume of drainage. The relationship between the duration and volume of drainage and hydrocephalus was analyzed. Results Of the 97 patients, 34 developed hydrocephalus, 41 developed subdural effusion, and 3 developed intracranial infection. There were 41 cases in the short-term group and 56 cases in the long-term group, and the mean duration of drainage was significantly shorter in the short-term group than in the long-term group (10±3.6 days vs 21±4.1 days, P<0.001). The long-term group had significantly higher incidence rates of hydrocephalus (44.6% vs 22.0%, P=0.021) and subdural effusion (53.6% vs 26.8%, P=0.008) than the short-term group; there was no significant difference in intracranial infection between the two groups (3.6% vs 3.2%, P=0.750). There were 53 cases in the low-volume group and 44 cases in the high-volume group, and the mean drainage volume was significantly lower in the low-volume group than in the high-volume group (183±42 ml vs 285±34 ml, P<0.001). The high-volume group showed significantly more frequent hydrocephalus (52.3% vs 20.8%, P=0.001) and subdural effusion (56.8% vs 30.2%, P=0.008) compared with the low-volume group; no significant difference was observed in intracranial infection between the two groups (2.3% vs 3.8%, P=0.0671). Conclusions Long duration and high volume of cerebrospinal fluid drainage are associated with the occurrence of hydrocephalus and subdural effusion post operation in patients with aSAH.