Clinical Question

Does mobile stroke unit dispatch improve outcomes?

Q: Mobile Stroke Unit Dispatch

B_PROUD (Berlin, 2021) and BEST-MSU (US, 2021) both demonstrated improved 90-day functional outcomes with mobile stroke unit dispatch versus conventional EMS. B_PROUD used a quasi-experimental design with ordinal mRS shift (common OR 0.71). BEST-MSU used alternating-week cluster randomization with utility-weighted mRS as the primary outcome. Both gain comes primarily from earlier tPA delivery. Implementation is constrained by cost and population density; the optimal MSU operational model and value-per-population threshold remain open questions.

Synthesises 4 trialspatient-level functional outcomes from prehospital MSU programs and adjacent prehospital intervention trials

What does the guideline say?

§2.5 Mobile Stroke Units· 2026
In patients with suspected AIS, the use of MSUs over conventional EMS where available is recommended for the transport and management of thrombolytic-eligible patients to ensure the fastest achievable onset-to-treatment time and improve functional outcomes (COR 1, LOE A). In patients with suspected acute stroke, MSUs must be equipped to diagnose and treat patients with IVT (COR 1, LOE A). In patients with suspected acute stroke, MSU care, including streamlined protocols and use of neurological expertise, either in-person or remote telemedicine consultation, is beneficial for emergent evaluation and treatment of patient symptoms without safety concerns (COR 1, LOE B-R). In endovascular thrombectomy-eligible patients, use of MSUs can be beneficial to identify and triage patients to the appropriate thrombectomy-capable facility with prehospital notification of receiving stroke teams (COR 2a, LOE B-NR).
Source: 2026 AHA/ASA Guideline · §2.5 (Mobile Stroke Units)

The trials cited in the guideline's supportive text appear below.

Trials in this question· 4

RIGHT-22019

No benefitOR 1.25

Ultra-acute transdermal GTN for presumed stroke shows no benefit and a harm signal in ICH.

No benefitOR 1.25

B_PROUD2021

cOR 0.71cOR 0.71 (less mRS)

MSU dispatch in urban EMS shifts ordinal mRS toward less disability vs conventional ambulance.

cOR 0.71cOR 0.71 (less mRS)

BEST-MSU2021

MSU fasteruw-mRS OR 2.43