Presenter of 3 Presentations
HYPERACUTE ICH RECRUITMENT IN THE STOP-MSU TRIAL FACILITATED BY A MOBILE STROKE UNIT
SUSTAINED BENEFITS FOR THROMBECTOMY TRIAGE USING THE ACT-FAST ALGORITHM AFTER REAL-WORLD IMPLEMENTATION
Abstract
Background and Aims
The severity-based ACT-FAST algorithm for pre-hospital triage of large vessel occlusion (LVO) has previously been validated in a large paramedic-led study. We examined the subsequent real-world diagnostic utility of this tool for ambulance triage in the western metropolitan region of Melbourne, Australia.
Methods
A manual audit was conducted of all patients presenting to a central comprehensive center for patients in the catchment of two spoke primary centers where ACT-FAST bypass was active from April 2020 to March 2021. Diagnostic performance was determined for LVO and overall need for comprehensive center care, including and excluding concurrent mobile stroke unit (MSU) cases.
Results
Of 1222 presentations screened, 182 (15%) patients were in the bypass zone. These included 15 secondary inter-hospital LVO transfers, of which 9 had high severity (NIHSS≥10). In contrast, 23 ACT-FAST-Positive LVOs were bypassed (6 MSU-facilitated) in addition to 11 ICH and 1 intracerebral tumour. There were 8 bypassed false-positives (6 infarcts, 2 mimics) of which only 1 received thrombolysis. Bypassed patients received significantly faster EVT from ambulance dispatch (median 177min vs 237 min, p=0.001) whereas there was no significant difference in thrombolysis time (113min vs 101min, p=0.486).
Conclusions
Implementation of ACT-FAST triaging avoided >70% of secondary transfers for high-severity LVO with significant time savings to thrombectomy and low rates of false-positive bypass (<1/month). Thrombolysis delay was minimal in our metropolitan setting and triage benefit was complementary to that provided by an active MSU service in the area.
HYPERACUTE ICH RECRUITMENT IN THE STOP-MSU TRIAL FACILITATED BY A MOBILE STROKE UNIT
Abstract
Background and Aims
Previous studies of ICH have shown a strong relationship between time to treatment and hematoma growth. The phase IIb Stopping Haemorrhage with Tranexamic acid for Hyperacute Onset Presentation including Mobile Stroke Units (STOP-MSU) trial tests the effectiveness of tranexamic acid in ICH <2h from onset and is the first to involve MSU enrolment. We conducted a blinded analysis of the ongoing trial to evaluate the effect of MSU-facilitated recruitment on time metrics and hematoma expansion.
Methods
Blinded clinical and imaging data were analyzed from the first consecutive 127 trial patients. Time metrics and hematoma expansion (defined as >6mL or >33% growth from baseline to 24h±6) were compared between MSU and non-MSU (in-hospital enrolled) participants.
Results
Mean participant age was 66 years (58% male) with 26% recruited on MSU. Compared to non-MSU participants, MSU-enrolled participants had faster median onset-to-medical-contact (41 vs 57min, p=0.015) and CT-to-treatment (17 vs 32min, p<0.001), resulting in significantly faster median onset-to-treatment times (75 vs 107min, p<0.001). MSU participants accounted for 88% of treatments ≤60min and 51% ≤90min. The overall rate of hematoma growth was 48%, with MSU participants 54% (95%CI 35-76) and non-MSU 45% (95%CI 35-56).
Conclusions
In this blinded analysis, MSU recruitment accounted for most of the ultra-early treatments within the STOP-MSU trial, likely due to efficient pre-hospital management. Hematoma expansion was very common in both MSU and non-MSU participants, despite the trial not mandating a CT-angiography spot-sign. The completed trial will examine whether ultra-early tranexamic acid treatment results in meaningful attenuation of hematoma expansion and improved functional outcomes.