Abstract Body: Introduction: Guidelines for aneurysmal subarachnoid hemorrhage (aSAH) suggest attempting aneurysm securement within 24 hours from arrival; the optimal treatment window within that timeframe is under investigation. We studied the association between time from hospital arrival to aneurysm treatment and outcomes in aSAH.

Methods: We performed a retrospective study of patients with aSAH presenting from 2015 to 2023 to a single academic center. Both multivariate logistic regressions (MLR) and multivariate generalized additive models (MGAM) were created to analyze both logistic and nonlinear relationships between time interval from arrival to endovascular treatment, with poor neurologic outcome at 3 months defined as modified Rankin scale (mRS) scores of 4-6 as the primary outcome. In addition, subgroup analyses were performed for arrival-to-treatment times among patients with Hunt and Hess (HH) grades ≥3. Finally, we analyzed arrival-to-treatment time and risk of preprocedural aneurysmal rebleeding.


Results: We reviewed 434 patients with ruptured aSAH and excluded 96 patients who died prior to cerebral angiogram, required emergent surgery, or were beyond 95% of all arrival-to-treatment times, resulting in a cohort of 338 aSAH who received endovascular aneurysm treatment in final analysis (mean [SD] age, 57.5 [13.9]; 64.2% female, 71.0% white), of which 94.9% (n=321) patients were treated within 24 hours of hospital arrival, and 5.1% (n=17) had preprocedural aneurysm rebleeding. In MLR, longer arrival-to-treatment time was not associated with neurologic outcome at 3-months (OR 0.69, 95%CI [0.43, 1.09], p=0.12). MGAM was also not associated with differences in mRS ≥3 at 3-month follow-up (estimated degrees of freedom [edf] 1, p=0.11). Restricting to patients with high HH, both MLR and MGAM demonstrated longer arrival-to-treatment intervals were associated with decreased odds of unfavorable 3-month neurologic outcome (OR 0.56, 95%CI [0.33, 0.95], p=0.036], graphic 1 for MLR and edf=1, p=0.040, graphic 2 for MGAM). Longer arrival-to-treatment was not associated with increased risk of preprocedural aneurysmal rebleeding on MLR (OR 1.56, 95%CI [0.72, 3,83] p=0.3).

Conclusions: We found that longer time-to-treatment within the recommended timeframe was associated with better neurologic outcomes among patients with higher HH grade. This may underscore the need for thorough resuscitation before aneurysm securement among critically ill patients.