Abstract DP156: Changes in Hospital Capabilities to Connect Patients to Endovascular Thrombectomy Over Time

Background: Since endovascular thrombectomy (EVT) became standard of care in 2015, stroke systems-of-care have adapted to increase the number of acute ischemic stroke (AIS) patients who can access EVT. Our objective was to characterize how California hospitals have changed their EVT capabilities over time based on the provision of EVT procedures (high or low volume) and the transfer of patients to EVT-capable hospitals from non-EVT-capable hospitals. Methods: We identified all AIS encounters in statewide all-payer data from the California Department of Health Care Access and Information from 2016-2021. EVT treatment status of each encounter was determined based on ICD-10 PCS and MS-DRG codes. Hospitals were categorized into 4 mutually exclusive groups annually based on how they provided EVT care: 1) high-volume EVT hospital (meeting The Joint Commission standard of conducting 15 EVT procedures in the past year ), 2) low-volume EVT-capable hospital (conducting 2-14 EVT procedures in the past year), 3) gateway hospital (no EVT capability but transferred at least one AIS patient to an EVT-capable hospital) and 4) gap hospital (no EVT capability and no AIS patient transferred to an EVT-capable hospital). Stroke encounters were attributed to the initial hospital of presentation. We used linear regression models to examine trends over time. Results: There were 264,661 AIS encounters in California from 2016-2021. The number of hospitals caring for AIS patients each year ranged from 298 (in 2020) to 316 (in 2016). The number of low-volume EVT hospitals decreased modestly from 28 (8.9%) in 2016 to 23 (7.6%) in 2021 as the number of high-volume EVT hospitals increased from 42 (13.3%) in 2016 to 62 (20.4%) in 2021 (Figure 1). The number of gateway hospitals decreased over the study period as more hospitals expanded EVT capability and high-volume EVT status, while the number of gap hospitals remained relatively stable over time (Table 1). At the encounter level, an increasing proportion of patients presented to high-volume EVT centers over the study period while the number of patients presenting to gateway hospitals declined as EVT capability grew (Tables 1 and 2). Conclusions: Most patients with stroke in California present to hospitals with capabilities to provide EVT directly or are transferred to them. While an increasing number of hospitals are performing EVT for stroke patients, many do not meet the TJC-recommended volume threshold.