Grant: Travel Awards - Institute Community Support

Ischemic stroke with large vessel occlusion (LVO) is a time sensitive disease requiring immediate treatment. However, ischemic stroke with LVO can not be definitively identified in the field by paramedics. Clinical triage tools facilitate pre-hospital recognition of LVO so these patients can be routed for the most appropriate treatment. There are two treatment options: 1) transport to community hospital for medical treatment and then immediate transfer to urban tertiary hospital for surgical treatment (drip and ship) or 2) transport directly to urban tertiary hospital for surgical treatment (mothership). These clinical triage tools have variable positive predictive value (PPV) in identifying LVO, which impacts transport decision-making. Using previously developed conditional probability models, we modelled the effects of the Los Angeles Motor Scale (LAMS) and Ambulance Clinical Triage-For Acute Stroke Treatment (ACT-FAST) algorithm, both with different PPV, on transport strategies for ischemic stroke patients with LVO in Victoria, Australia. As the PPV of ACT-FAST is higher than LAMS (56% vs 43%) the areas where mothership predicts the best outcome are larger especially if treatment at the community hospital is slow. Due to the efficacy of surgical treatment for LVO stroke a LVO triage tool with a higher PPV, such as ACT-FAST, will increase the area where mothership predicts the greatest probability of good outcome for patients with suspected LVO. The triage tool used has impact on organizing pre-hospital transport systems and protocols.