The Benefits and Feasibility of External Lumbar Cerebrospinal Fluid Drainage for Cerebral Vasospasm in Patients with Aneurysmal Subarachnoid Hemorrhage: Meta-Analysis and Trial Sequential Analysis

Cerebral vasospasm after aneurysmal subarachnoid hemorrhage is a main cause contributing to poor outcomes. Removal of blood from the subarachnoid may decrease development of cerebral vasospasm. The purpose of this study is to determine the effect of lumbar cerebrospinal fluid (CSF) drainage on cerebral vasospasm and related complications through meta-analysis and trial sequential analysis (TSA).A systematic search of the literature was performed. Case-control studies of the effects of external lumbar drainage in patients with subarachnoid hemorrhage were included. The association between lumbar drain and vasospasm, cerebral infarction, subsequent treatment, and mortality were evaluated.Eleven of 122 articles were included in the meta-analysis. Lumbar CSF drainage reduces occurrence of vasospasm and related complications. In meta-analysis, the pooled odds ratio for symptomatic vasospasm, cerebral infarct, endovascular treatment for vasospasm, and mortality was 0.40 (95% confidence interval [CI], 0.31-0.51; P = 0.00001), 0.47 (95% CI, 0.35-0.62; P0.0001), 0.29 (95% CI, 0.18-0.46; P0.0001), and 0.41, (95% CI, 0.23-0.74; P = 0.003), respectively, compared with the non-lumbar drainage group. In TSA, the cumulative Z line crossed α-spending boundaries and reached the required sample size in analysis of symptomatic vasospasm and endovascular treatment for vasospasm.Lumbar CSF drainage can decrease symptomatic vasospasm, cerebral infarction, subsequent endovascular treatment, and mortality. Through TSA, the accuracy and reliability of the effect of lumbar CSF drainage-related cerebral vasospasm and endovascular treatment are increased. Further studies of the association between lumbar drain and cerebral infarction and mortality are required to confirm the generalization of the results.