Cortical symptoms described in emergency calls for patients with suspected large vessel occlusion: a descriptive analysis of 157 emergency calls

A hybrid strategy using an ambulance and a helicopter to convey thrombectomy candidates to definite care: a prospective observational study

BACKGROUND

Mechanical thrombectomy is the treatment of choice for large vessel occlusion strokes done only in comprehensive stroke centres (CSC). We investigated whether the transportation time of thrombectomy candidates from another hospital district could be reduced by using an ambulance and a helicopter and how this affected their recovery.

METHODS

We prospectively gathered the time points of thrombectomy candidates referred to the Tampere University Hospital from the hospital district of Southern Ostrobothnia. Primary and secondary transports were included. In Hybrid transport, the helicopter emergency medical services (HEMS) unit flew from an airport near the CSC to meet the patient during transport and continued the transport to definitive care. Ground transport was chosen only when the weather prevented flying, or the HEMS crew was occupied in another emergency. We contacted the patients treated with mechanical thrombectomy 90 days after the intervention and rated their recovery with the modified Rankin Scale (mRS). Favourable recovery was considered mRS 0-2.

RESULTS

During the study, 72 patients were referred to the CSC, 71% of which were first diagnosed at the PSC. Hybrid transport (n = 34) decreased the median time from the start of transport from the PSC to the computed tomography (CT) at the CSC when compared to Ground (n = 17) transport (84 min, IQR 82-86 min vs. 109 min, IQR 104-116 min, p < 0.001). The transport times straight from the scene to CT at the CSC were equal: median 93 min (IQR 80-102 min) in the Hybrid group (n = 11) and 97 min (IQR 91-108 min) in the Ground group (n = 10, p = 0.28). The percentages of favourable recovery were 74% and 50% in the Hybrid and Ground transport groups (p = 0.38) from the PSC. Compared to Ground transportation from the scene, Hybrid transportation had less effect on the positive recovery percentages of 60% and 50% (p = 1.00), respectively.

CONCLUSION

Adding a HEMS unit to transporting a thrombectomy candidate from a PSC to CSC decreases the transport time compared to ambulance use only. This study showed minimal difference in the recovery after thrombectomy between Hybrid and Ground transports.

Impact of the first response unit on prehospital on-scene time among paramedic-suspected stroke patients: a retrospective before-after cohort study in Finland

BACKGROUND

Revascularization of an occluded artery by either thrombolysis or mechanical thrombectomy is a time-critical intervention in ischaemic stroke. Each link in the stroke chain of survival should minimize the delay to definitive treatment in every possible way. In this study, we investigated the effect of routine dispatch of a first response unit (FRU) on prehospital on-scene time (OST) on stroke missions.

METHODS

Medical dispatch of FRU together with an emergency medical service (EMS) ambulance was a routine strategy in the Tampere University Hospital area before 3 October 2018, after which the FRU has only been dispatched to medical emergencies on the decision of an EMS field commander. This study presents a retrospective before-after analysis of 2,228 paramedic-suspected strokes transported by EMSs to Tampere University Hospital. We collected data from EMS medical records from April 2016 to March 2021, and used statistical tests and binary logistic regression to detect the associations between the variables and the shorter and longer half of OSTs.

RESULTS

The median OST of stroke missions was 19 min, IQR [14-25] min. The OST decreased when the routine use of the FRU was discontinued (19 [14-26] min vs. 18 [13-24] min, p < 0.001). The median OST with the FRU being the first at the scene (n = 256, 11%) was shorter than in cases where the FRU arrived after the ambulance (16 [12-22] min vs. 19 [15-25] min, p < 0.001). The OST with a stroke dispatch code was shorter than with non-stroke dispatches (18 [13-23] min vs. 22 [15-30] min, p < 0.001). The OST for thrombectomy candidates was shorter than that for thrombolysis candidates (18 [13-23] min vs. 19 [14-25], p = 0.01). The shorter half of OSTs were associated with the FRU arriving first at the scene, stroke dispatch code, thrombectomy transportation and urban location.

CONCLUSION

The routine dispatch of the FRU to stroke missions did not decrease the OST unless the FRU was first to arrive at the scene. In addition, a correct stroke identification in the dispatch centre and thrombectomy candidate status decreased the OST.