Introduction Patients with an unruptured intracranial aneurysm treated with coil embolization are routinely admitted to the intensive care unit (ICU) after the procedure; however, this practice is questionable. The purpose of this study was to determine if routine admission to the ICU is necessary for patients undergoing coil embolization of an unruptured intracranial aneurysm.

Methods We conducted a retrospective cohort study of all patients undergoing elective endovascular treatment of an unruptured intracranial aneurysm between 2005 and 2012 at our institution. Multivariate regression analysis was performed to identify predictors of outcome. Cost savings analysis compared ICU admission to step-down or telemetry unit admission.

Results 311 unruptured intracranial aneurysms were treated by coil embolization (190), balloon remodeling (13), or stent-assisted coiling (108). Eleven (3.5%) neurologic complications were noted; 5 (1.6%) of these were permanent. Multivariate regression analysis identified female sex (p=0.028), hypercoagulability (p=0.021), aneurysm size >2 cm (p=0.003), and intraoperative rupture (p<0.001) as predictors of a post-procedural neurologic complication. Cost savings were 57% for admission to a step-down unit and 32% for admission to a telemetry unit compared with ICU admission.

Conclusions Neurologic complications are rare in the treatment of unruptured intracranial aneurysms, suggesting that routine ICU admission after treatment may not be necessary. Female sex, history of hypercoagulability, aneurysm size >2 cm, and an intraprocedural rupture were predictive of a postoperative complication. ICU monitoring in these subgroups may therefore be warranted.