Long Distance Air Ambulance Transfers for Endovascular Thrombectomy.

Area of Science:

• Neuroscience
• Cardiovascular Medicine
• Emergency Medicine

Background:

• Endovascular thrombectomy (EVT) is a critical stroke treatment often requiring transfer to comprehensive stroke centers (CSCs).
• Patients initially presenting to primary stroke centers (PSCs) may be transferred via road ambulance or helicopter emergency medical services (HEMS).

Purpose of the Study:

• To compare outcomes of patients transferred for EVT via HEMS versus metropolitan transfer groups.
• To evaluate the efficacy and safety of HEMS in facilitating timely EVT for stroke patients.

Main Methods:

• Retrospective observational study in a regional stroke network.
• Comparison of HEMS transfers with direct-to-CSC and metropolitan PSC-to-CSC transfers using national EVT registry data.
• Primary outcome: day 90 functional independence (modified Rankin Scale 0-2); Secondary outcome: day 90 mortality.

Main Results:

• HEMS patients (28%) had longer onset-to-EVT-groin times but similar day 90 functional independence and mortality rates compared to metropolitan groups.
• No significant difference in day 90 independence was observed between HEMS and metro PSC-to-CSC transfer groups.
• Direct-to-CSC patients showed a trend towards better independence, but overall mortality was similar across all groups.

Conclusions:

• HEMS transfers for EVT yield comparable functional outcomes to metropolitan transfers, despite increased travel distances and times.
• Comprehensive stroke centers should consider HEMS transfers from distant PSCs for EVT, as outcomes are not compromised.
• The study supports the integration of HEMS into stroke networks to broaden access to EVT.