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Given the narrow time windows of opportunity associated with the various interventional stroke therapies and the clearly demonstrated benefit of earlier treatment, EMS is a critical link to ensuring that patients arrive at facilities capable of treating strokes in an expedited manner. Numerous studies have shown that stroke patients accessing the EMS system have a significantly greater chance of timely arrival at an emergency department, which in turn, can promote higher thrombolytic treatment rates [29–32]. More specifically, the California Acute Stroke Prototype Registry (CASPR) collected data from several California hospitals to identify factors that resulted in delayed presentation for treatment. This study indicated that if patients experiencing stroke symptoms (that did not occur overnight) had called EMS immediately, the percentage eligible for tPA would have increased from 4.3% to 28.6% [33]. Furthermore, one randomized trial examining the effect of an intervention comprised of a prehospital stroke assessment tool, an ambulance protocol for hospital bypass for potential thrombolysis‐eligible patients, and prehospital notification of the acute stroke team demonstrated a significant increase in thrombolytic administration. In this study, the time from symptom onset to ED arrival decreased from 150 minutes to 90 minutes, and the proportion of patients receiving tPA increased from 4.7% to 21.4% after the intervention, with 43% of patients having minimal to no disability at 3 months [34].

Knowledge of the stroke treatment capabilities among area hospitals is quite important. Health care facilities that are not stroke centers may be able to administer tPA, but often lack the capability to perform more invasive procedures such as intra‐arterial tPA administration or endovascular thrombectomy [24, 35]. These procedures require an interventional neuroradiologist. In addition, dedicated personnel must be available quickly and trained in the evaluation of stroke. The staffing of EDs throughout the country still varies widely, as does the relative stroke experience of practitioners. Designation by The Joint Commission indicates that a hospital has been evaluated and found to be compliant with specific national guidelines [36, 37].

Currently, The Joint Commission certifies hospitals at the following levels: Acute Stroke Ready Hospital, Primary Stroke Center, Thrombectomy‐Capable Stroke Center, and Comprehensive Stroke Center [38, 39]. The process of certifying hospitals as stroke centers depends on whether they meet specific criteria defined by The Joint Commission, which include availability of a stroke team, neurology consultation, and diagnostic and therapeutic capabilities (Table 18.4) [38]. Acute Stroke Ready Hospitals are able to deliver thrombolytics and promptly transfer patients to a higher‐level center. Primary Stroke Centers have committed to the rapid assessment and treatment with IV thrombolytics as well as an ability to admit acute stroke patients. A designation of Thrombectomy‐Capable or Comprehensive Stroke Center indicates those hospitals are uniquely equipped and staffed to treat the more complex stroke cases.

Each EMS agency must evaluate the community it serves, including its available resources, and then work to develop appropriate patient care guidelines for the evaluation and treatment of stroke patients. This should be done in conjunction with the local and regional health care facilities. It should be determined whether the local community hospital is capable of managing acute stroke victims. Hospital transport destinations should be predetermined based on time and distance variables. In addition, air medical transport may be considered, including direct air medical evacuation of stroke patients from the scene. Air medical transport may be an appropriate option if the ground EMS transport time is expected to exceed 1 hour, and the air medical crew could arrive at a stroke center in time to facilitate appropriate evaluation and treatment within the therapeutic window. In making such a decision, it is important to consider all the elements of air medical response that consume time, including lift time, flight time, time for patient evaluation, and time to load and unload. Guidelines that include air medical dispatch based on telecommunicator information may be considered, specifically for rural areas without local health facilities capable of stroke interventions.

Table 18.4 Joint Commission stroke center comparison

	ASRH	PSC	TSC	CSC
Eligibility	Stroke protocols based on evidence‐based standards	Stroke protocols based on evidence‐based standards	Stroke protocols based on evidence‐based standardsPerformed at least 15 mechanical thrombectomy procedures over past 12 months (or over 30 in past 24 months)	Stroke protocols based on evidence‐based standardsPerformed at least 15 mechanical thrombectomy procedures over past 12 months (or over 30 in past 24 months)
Program Medical Director	Possesses sufficient knowledge of cerebrovascular disease	Possesses sufficient knowledge of cerebrovascular disease	Possesses background in neurology	Possesses extensive expertise 24/7
Acute Stroke Team	Available 24/7, at bedside within 15 min	Available 24/7, at bedside within 15 min	Available 24/7, at bedside within 15 min	Available 24/7, at bedside within 15 min
EMS Collaboration	Access to EMS protocols	Access to EMS protocols	Access to EMS protocols, routing plans, records from transfer	Access to EMS protocols, routing plans, records from transfer
Stroke Unit	No designated beds for stroke patients	Has designated beds for acute stroke patients	Has Neuro ICU and on‐site critical care 24/7	Has Neuro ICU and on‐site neurointensivist 24/7
Diagnostic Capabilities	CT, labs 24/7 (MRI 24/7 if used)	CT, MRI (if used), labs 24/7; CTA and MRA; at least one cardiac imaging modality	CT, MRI, labs, CTA, MRA, catheter angiography 24/7; cranial and duplex ultrasound; TEE	CT, MRI, labs, CTA, MRA, catheter angiography 24/7; cranial and duplex ultrasound; TEE
Neurologist Accessibility	24/7 in person or via telemed	24/7 in person or via telemed	24/7 in person or via telemed; call schedule	Meets needs of multiple complex stroke patients; 24/7 call schedule
Neurosurgical Services	Within 3 hours via transfer	Within 2 hours; OR available 24/7 that provides neurosurgery	Within 2 hours; OR available 24/7 that provides neurosurgery	24/7 availability; neurointerventionist; neuroradiologist; neurologist; neurosurgeon
Treatment Capabilities	IV thrombolytics and transfer	IV thrombolytics and medical management	IV and IA thrombolytics; mechanical thrombectomy	IV thrombolytics; endovascular therapy; microsurgical clipping of aneurysms, stenting, and carotid surgery
Research	N/A	N/A	N/A	Participates in IRB‐approved stroke research

ACRS, Acute Stroke Ready; PSC, Primary Stroke Center; TSC, Thrombectomy‐Capable Stroke Center; CSC, Comprehensive Stroke Center. Source: Adapted from The Joint Commission ‐ The Stroke Certification Programs – Program Concept 2019. https://www.jointcommission.org/‐/media/tjc/documents/accred‐and‐cert/certification/certification‐by‐setting/stroke/dsc‐stroke‐grid‐comparison‐chart.pdf. Accessed 8/7/2020.

Air medical transport of stroke patients in rural areas may facilitate access to thrombolytic treatment or thrombectomy for LVO strokes. Many hospitals and their EDs, especially smaller rural facilities, still lack resources and refined processes for rapidly evaluating possible stroke patients and administering tPA. In some cases, using air medical services markedly increases the proportion of patients treated with thrombolytics [40]. It seems clear that the role of medical helicopter transport as part of regional systems of care is expanding [41].