The Impact of Conscious Sedation versus General Anesthesia for Stroke Thrombectomy on the Predictive Value of Collateral Status: A Post Hoc Analysis of the SIESTA Trial.

Background and Purpose: Radiologic selection criteria to identify patients likely to benefit from endovascular stroke treatment are still controversial. In this post hoc analysis of the recent randomized Sedation versus Intubation for Endovascular Stroke TreAtment (SIESTA) trial, we aimed to investigate the impact of sedation mode (conscious sedation versus general anesthesia) on the predictive value of collateral status.
Materials and Methods: Using imaging data from SIESTA, we assessed collateral status with the collateral score of Tan et al and graded it from absent to good collaterals (0-3). We examined the association of collateral status with 24-hour improvement of the NIHSS score, infarct volume, and mRS at 3 months according to the sedation regimen.
Results: In a cohort of 104 patients, the NIHSS score improved significantly in patients with moderate or good collaterals (2-3) compared with patients with no or poor collaterals (0-1) ( P = .011; mean, -5.8 ± 7.6 versus -1.1 ± 10.7). Tan 2-3 was also associated with significantly higher ASPECTS before endovascular stroke treatment (median, 9 versus 7; P < .001) and smaller mean infarct size after endovascular stroke treatment (median, 35.0 versus 107.4; P < .001). When we differentiated the population according to collateral status (0.1 versus 2.3), the sedation modes conscious sedation and general anesthesia were not associated with significant differences in the predictive value of collateral status regarding infarction size or functional outcome.
Conclusions: The sedation mode, conscious sedation or general anesthesia, did not influence the predictive value of collaterals in patients with large-vessel occlusion anterior circulation stroke undergoing thrombectomy in the SIESTA trial.
(© 2017 by American Journal of Neuroradiology.)