Analysis and Modelling of the Thrombolysis Process for Acute Ischemic Stroke Patients at Urban and Rural Hospitals

Abstract

Background: Thrombolysis is the process of treating acute ischemic stroke (AIS) patients with tissue plasminogen activator (tPA), where effectiveness critically relies on rapid treatment. Fast treatment with tPA has been reported in many urban hospitals, but rural hospitals struggle to reduce treatment times. The study objectives are as follows: 1) to analyze healthcare professionals’ views on various treatment topics in Nova Scotia; 2) to map and compare the thrombolysis treatment process in urban and rural settings in Nova Scotia; 3) to provide a detailed conceptual framework of the thrombolysis process focusing on intra-hospital activities; and 4) to assess the potential impact of process improvements that can result in faster door-to-needle time (DNT) when applied to urban and rural settings.

Methods: Structured interviews were conducted with healthcare professionals involved in stroke treatment across three Nova Scotian hospitals (1 urban and 2 rural). Interview data were used to develop a detailed process map for each site, which provided the foundation to then create a conceptual framework. The interview results and conceptual framework were used to develop an ARENA discrete-event simulation (DES) model to replicate treatment processes at both urban and rural hospitals.

Results: There were 23 health care professionals interviewed at 3 sites. The analysis of the interview data showed a total of 11 urban-rural treatment differences. Additionally, 11 patient-related and 29 system treatment delays were found. Five scenarios were tested with the DES model, using median DNT as the primary outcome measure. The scenario results include the following maximum DNT reductions: patients arriving via Emergency Medical Services (EMS) remaining on the EMS stretcher to imaging (9.2%, 95% CI 7.9 – 10.5), administration of tPA in the imaging area (12.6%, 95% CI 12.4 – 12.8), pre- registering patients arriving via EMS (1.7%, 95% CI 0.3 – 3.1), reducing both the treatment decision time and tPA preparation time by 35% (11.0%, 95% CI 10.0 – 12.0), and combining all scenarios (26.7, 95% CI 24.5 – 28.9%).

Conclusions: The majority of treatment delays encountered are system delays. There is a general consensus that there is an urban-rural treatment gap, and physicians in rural settings are more hesitant to treat with tPA. The detailed conceptual framework further clarifies intra-hospital logistics of the thrombolysis process. Significant DNT improvements are achievable in urban and rural settings through implementing process changes and reducing activity durations.