Workflow and factors associated with delay in the delivery of intra-arterial treatment for acute ischemic stroke in the MR CLEAN trial

Esmee Venema*, Nikki Boodt, Olvert A. Berkhemer, Pleunie P. M. Rood, Wim H. van Zwam, Robert J. van Oostenbrugge, Aad van der Lugt, Yvo B. W. E. M. Roos, Charles B. L. M. Majoie, Hester F. Lingsma, Diederik W. J. Dippel, MR CLEAN Investigators

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Objective The effect of intra-arterial treatment (IAT) for acute ischemic stroke is highly time-dependent. We investigated the delay of IAT and factors associated with such delay. Methods MR CLEAN was a randomized trial of IAT plus usual care versus usual care alone (n=500). With multivariable linear regression, we analyzed the effect of intravenous treatment, general anesthesia, off-hours and inter-hospital transfer on time to admission to the emergency department (ED) of the intervention center and time to treatment. Furthermore, we assessed compliance with a target of 75min for time from ED to treatment, and calculated the potential absolute increase in the number of patients with a good outcome (modified Rankin Scale score <= 2) if this target had been achieved in all treated patients. Results Inter-hospital transfer prolonged time to ED by 140min (95% CI 129 to 150) but reduced time from ED to treatment by 77min (95% CI 64 to 91). Time from ED to treatment was increased by 19min by general anesthesia (95% CI 5 to 33) and total time was increased by 23min during off-hours (95% CI 6 to 40). The in-hospital target was achieved in 11.5% (22/192) of patients. Full compliance with the target time of 75min from ED to treatment would have increased the proportion of patients with a good outcome by 7.6% (95% CI 6.7% to 8.5%). Conclusion Inter-hospital transfer is an important cause of delay in the delivery of IAT and every effort should be made to avoid transfers and reduce transfer-related delay. Furthermore, in-hospital workflow should be optimized to improve functional outcome after IAT.
Original languageEnglish
Pages (from-to)424-U19
Number of pages6
JournalJournal of Neurointerventional Surgery
Issue number5
Publication statusPublished - 30 Aug 2017


  • stroke
  • thrombectomy
  • TIME

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