# Impact of the drip-and-ship model on the treatment of acute ischemic stroke in relation to distance from the thrombectomy center

## TL;DR

This study examines how distance from a stroke treatment center affects outcomes for patients using the drip-and-ship model for acute ischemic stroke.

## Contribution

The study identifies how proximity to a thrombectomy center influences treatment times and outcomes in stroke patients.

## Key findings

- Patients closer to the center had shorter times to admission and treatment.
- No significant difference in 90-day outcomes between direct and drip-and-ship admissions.
- Closer proximity was associated with better functional outcomes (mRS <3).

## Abstract

The drip-and-ship model is a common practice for patients with ischemic stroke due to large-vessel occlusion (LVO), providing initial diagnostics and thrombolysis in transition to endovascular treatment (EVT). However, hospital transfer results in treatment delays for patients requiring EVT, potentially affecting outcomes. We sought to explore the association between distance from residence and time intervals to admission with clinical outcomes after EVT.

In this monocentric retrospective cohort study, patients with acute ischemic stroke due to LVO who underwent EVT at Frankfurt University Hospital between 2017 and 2023 were analyzed. Patients were grouped according to direct-to-center (DC) or drip-and-ship (DS) admission. Clinical outcome parameters included patient global disability after 90 days as measured by the modified Rankin Scale (mRS) and National Institutes of Health Stroke Scale (NIHSS) score improvements analyzed in relation to geographical distance and time metrics. A subgroup analysis based on the distance from residence in 10 km intervals was added.

A total of 334 patients were included. Of these, 41.9% were DC admissions and 58.1% DS were admissions. Distances from home to center were shorter for DC patients (11.1 km vs. 36.4 km, p < 0.001), resulting in significantly shorter times from symptom onset to admission (−114 min; 71 min vs. 185 min; p < 0.001) and to flow restoration (−88 min; 213 min vs. 301 min; p < 0.001). After 90 days, no significant differences in clinical outcomes between DC and DS were observed. However, DC patients living closer than 10 km to the center were more likely to achieve an mRS score <3 (OR 2.995; 95%-CI 1.296–7.318; p = 0.012).

Proximity of residence to a thrombectomy center may be advantageous for stroke patients, most likely in association with direct pre-hospital transfers. Distances above 30 km more frequently led to drip-and-ship, which may facilitate care through early diagnostics as, signified by a reduction in the relative time delay to flow restoration.