Geographic Modelling of Endovascular Treatment Access Across Canada Demonstrates Need to Lower Door-in-Door-Out Times

Timely access to endovascular treatment (EVT) for ischaemic stroke patients is critical for optimal outcomes, but Canada's size and population distribution create barriers to access. EVT is mostly available in tertiary centres located in large urban cities, and patients that arrive at intravenous thrombolysis (IVT)-only stroke centres need to be transferred for EVT.

Geographic modelling of access to an IVT-only centre and an EVT-capable centre was conducted for Canada. Canada was divided into small grid sections. Drive times from the centre of each grid section to the closest stroke centres and the population of each grid section were obtained. The onset to paramedic arrival time and on-scene time were assumed to be 30 and 30 minutes, respectively. In the suboptimal and optimal scenarios, the door-in-door-out (DIDO) times were 150 minutes and 45 minutes, respectively. The poor access regions and population were calculated for onset to thrombolysis at 4.5 hours and to EVT-capable centre arrival for EVT within 6 and 3 hours.

The results show 99.37% of the population having access to thrombolysis within 4.5 hours. However, with a suboptimal DIDO time, 13.6% (5.2 million people) and 42.7% (16.2 million people) do not have access to EVT within 6 and 3 hours, respectively. With an efficient DIDO time, an additional 5.6% (2.1 million people) and 15.7% (6.0 million people) have access to EVT within 6 and 3 hours, respectively.

There is an imperative to reduce DIDO times to an ambitious median of 45 minutes to ensure optimal access to EVT across Canada.