Drip-and-ship toward mothership model for mechanical thrombectomy during COVID-19 pandemic: a retrospective analysis

During the first wave of the COVID-19 pandemic in spring 2020, our stroke network shifted from a drip-and-ship strategy (transport of acute ischemic stroke patients to the nearest primary stroke centers) toward a mothership model (direct transportation to the Comprehensive Stroke Center). We retrospectively analyzed stroke network performances comparing the two models.

All spoke-district patients treated with endovascular thrombectomy (EVT) between 15th March-15th June 2019 (drip-and-ship) and 2020 (mothership) were considered. We compared onset-to-groin time (OGT) and onset-to-needle time (ONT) between the two periods. Secondarily, we investigated other performances parameters (percentage of IV thrombolysis, timing of diagnostic and treatment) and clinical outcome (3-month modified Rankin Scale).

Twenty-four spoke-district patients in 2019 (drip-and-ship) and 26 in 2020 (mothership) underwent EVT. The groups did not differ for age, sex, risk factors, pre-stroke mRS 0-1, NIHSS, and ASPECTS distribution. The MS model showed a significant decrease of the OGT (162.5 min vs 269 min, p = 0.001) without significantly affecting the ONT (140.5 min vs 136 min, p = 0.853), ensuring a higher number of IV thrombolysis in combination with EVT (p = 0.030). The mothership model showed longer call-to-door time (median + 23 min, p < 0.005), but shorter door-to-needle (median - 31 min, p = 0.001), and door-to-groin time (- 82.5 min, p < 0.001). We found no effects of the stroke network model on the 3-month mRS (ordinal shift analysis, p = 0.753).

The shift to the mothership model during the COVID-19 pandemic guaranteed quicker EVT without significantly delaying IVT.