Influences of different referral modes on clinical outcomes after endovascular therapy for acute ischemic stroke

As endovascular thrombectomy (EVT) is time-dependent, it is crucial to refer patients promptly. Current referral modes include Mothership (MS), Drip and Ship (DS) and Drive the Doctor (DD). The purpose of this study was to investigate the influences of different referral modes on the clinical outcomes of patients with acute ischemic stroke after EVT.  METHODS: A total of 349 patients from 15 hospitals between April 2017 and March 2020 were enrolled. The primary outcomes include poor outcome (modified Rankin Scale score of 3 to 6), symptomatic intracranial hemorrhage transformation (sICH), mortality and cost. Regression analysis was used to assess the association of referral modes with poor outcome, sICH, mortality and cost in acute ischemic stroke patients.

Among the 349 patients, 83 were in DD group (23.78%), 85 in MS group (24.36%) and 181 in DS group (51.86%). There were statistically significant differences in intravenous thrombolysis, onset-to-door time, onset-to-puncture time, puncture-to-recanalization time, door-to-puncture time, door-to-recanalization time, and cost among the DD, MS, and DS groups (59.04% vs 35.29% vs 33.15%, P<0.001; 90 vs 166 vs 170 minutes, P<0.001; 230 vs 270 vs 270 minutes, P<0.001; 82 vs 54 vs 51 minutes, P<0.001; 110 vs 85 vs 96 minutes, P=0.004; 210 vs 146 vs 150 minutes, P<0.001; 64258 vs 80041 vs 70750 Chinese Yuan, P=0.018). In terms of sICH, mortality and poor outcome, there was no significant difference among the DD, MS, and DS groups (22.89% vs 18.82% vs 19.34%, P=0.758; 24.10% vs 24.71% vs 29.83%, P=0.521; 64.47% vs 64.71% vs 68.51%, P=0.827). The results of multiple regression analysis indicated that there was no independent correlation between different referral modes regarding sICH (OR_MS: 0.50, 95%CI: 0.18, 1.38, P=0.1830; OR_DS: 0.47, 95%CI: 0.19, 1.16, P=0.1000), mortality (OR_MS: 0.56, 95%CI: 0.19, 1.67, P=0.2993; OR_DS: 0.65, 95%CI: 0.25, 1.69, P=0.3744) and poor outcome (OR_MS: 0.61, 95%CI: 0.25, 1.47, P=0.2705; OR_DS: 0.53, 95%CI: 0.24, 1.18, P=0.1223). However, there was a correlation between MS group and cost (β=30449.73, 95%CI: 11022.18, 49877.29; P=0.0023). The multiple regression analysis on patients finally admitted in comprehensive stroke center (MS+DS) versus patients finally admitted in primary stroke center (DD) showed that DD mode was independently associated with lower costs (β=-19438.86, 95%CI: -35977.79, -2899.94; P=0.0219).

There was no independent correlation between three referral modes and sICH, mortality, poor outcome correspondingly. Different referral modes can be implemented in clinical practice according to the situations encountered. Compared to MS and DS modes, DD mode is more economical.