Changes in Cerebrospinal Fluid Interleukin-6 Levels after Surgical Treatment of Subarachnoid Hemorrhage

Background: We measured postoperative changes in cerebrospinal fluid (CSF) interleukin (IL)-6 levels in subarachnoid hemorrhage (SAH) due to aneurysm rupture and examined factors associated with outcomes and cerebral vasospasm. We used physiologic saline or artificial CSF as the intraoperative irrigation fluid and examined the differences. Methods: The participants were 16 men and 41 women who were transported to our facility for SAH and underwent surgical treatment during the period from February 2012 through March 2015. In terms of severity, 31 cases were World Federation of Neurological Surgeons (WFNS) grade I-III and 26 cases were grade IV-V. All cases underwent clipping. Physiologic saline and artificial CSF were used as intraoperative irrigation fluid. We placed a ventricular drainage tube intraoperatively and collected CSF daily from postoperative day (POD) 1 through 10 or until drain removal. Results: IL-6 level varied from 74 pg/mL to 407,936 pg/mL and peaked on PODs 1 and 5. Patients with favorable outcomes had significantly lower postoperative IL-6 levels. POD 1 IL-6 level significantly differed in relation to the presence of cerebral vasospasm but was not associated with its timing or severity. Use of artificial CSF was associated with a significantly lower incidence of cerebral vasospasm. Age and WFNS grade were significantly associated with outcome, and use of artificial CSF had a tendency toward favorable outcomes. Conclusions: Artificial CSF is a potentially useful intervention when managing subarachnoid hemorrhage. (J Nippon Med Sch 2024; 91: 402 & horbar;409)