Interhospital Transfer Before Thrombectomy Is Associated With Delayed Treatment and Worse Outcome in the STRATIS Registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke)

Evolving Stroke Systems of Care: Stroke Diagnosis and Treatment in the Post-Thrombectomy Era

Thrombectomy became the gold-standard treatment of acute ischemic stroke caused by large-vessel occlusions (LVO) in 2015 after five clinical trials published that year demonstrated significantly improved patient outcomes. In subsequent years, advances in stroke systems of care have centered around improving access to and expanding patient eligibility for thrombectomy. The prehospital and acute stroke treatment settings have had the greatest emphasis. Numerous prehospital stroke scales now provide emergency medical services with focused physical exams to identify LVOs, and many devices to non-invasively detect LVO are undergoing clinical testing. Mobile stroke units deployed throughout Western Europe and the USA also show promising results by bringing elements of acute stroke care directly to the patient. Numerous clinical trials since 2015 have aimed to increase candidates for thrombectomy by expanding indications and the eligibility time window. Further optimizations of thrombectomy treatment have focused on the role of thrombolytics and other adjunctive therapies that may promote neuroprotection and neurorecovery. While many of these approaches require further clinical investigation, the next decade shows significant potential for further advances in stroke care.

Patterns of Care in Patients with Basilar Artery Occlusion (BAO): A Population-Based Study

Basilar artery occlusion (BAO) is associated with high morbidity and mortality. Endovascular therapy (EVT) has been shown to be beneficial in acute BAO patients. This retrospective observational study used the National Inpatient Sample (NIS) database to identify BAO patients using the International Classification of Diseases (ICD). Multivariable models were used to evaluate the association of risk factors, comorbidities, length of stay (LOS) in hospital, total cost, disposition, and transfer status. A total of 1120 (447 females, 39.95%) patients were identified, with a higher proportion of White individuals (66.8% vs. 57.6%), atrial fibrillation (31.5% vs. 17.2%; p < 0.0001), and peripheral vascular disease (21.2% vs. 13.7%; p = 0.009). A lower proportion of individuals with diabetes mellitus (32.1% vs. 39.5%; p = 0.05) was found in the EVT group. Majority of the patients (924/1120, 82.5%) were treated at the urban teaching facility, which also performed most of the EVT procedures (164, 89.13%), followed by non-academic urban (166, 14.8%) and rural (30, 2.7%) hospitals. Most patients (19/30, 63%) admitted to rural hospitals were transferred to other facilities. Urban academic hospitals also had the highest median LOS (8.9 days), cost of hospitalization (USD 117,261), and disposition to home (32.6%). This study observed distinct patterns and geographical disparities in the acute treatment of BAO patients. There is a need for national- and state-level strategies to improve access to stroke care.

Interactive Direct Interhospital Transfer Network System for Acute Stroke in South Korea

BACKGROUND AND PURPOSE

Interhospital transfer is an essential practical component of regional stroke care systems. To establish an effective stroke transfer network in South Korea, an interactive transfer system was constructed, and its workflow metrics were observed.

METHODS

In March 2019, a direct transfer system between primary stroke hospitals (PSHs) and comprehensive regional stroke centers (CSCs) was established to standardize the clinical pathway of imaging, recanalization therapy, transfer decisions, and exclusive transfer linkage systems in the two types of centers. In an active case, the time metrics from arrival at PSH ("door") to imaging was measured, and intravenous thrombolysis (IVT) and endovascular treatment (EVT) were used to assess the differences in clinical situations.

RESULTS

The direct transfer system was used by 27 patients. They stayed at the PSH for a median duration of 72 min (interquartile range [IQR], 38-114 min), with a median times of 15 and 58 min for imaging and subsequent processing, respectively. The door-to-needle median times of subjects treated with IVT at PSHs (n=5) and CSCs (n=2) were 21 min (IQR, 20.0-22.0 min) and 137.5 min (IQR, 125.3-149.8 min), respectively. EVT was performed on seven subjects (25.9%) at CSCs, which took a median duration of 175 min; 77 min at the PSH, 48 min for transportation, and 50 min at the CSC. Before EVT, bridging IVT at the PSH did not significantly affect the door-to-puncture time (127 min vs. 143.5 min, p=0.86).

CONCLUSIONS

The direct and interactive transfer system is feasible in real-world practice in South Korea and presents merits in reducing the treatment delay by sharing information during transfer.

Association of Time of Day With Outcomes Among Patients Triaged for a Suspected Severe Stroke in Nonurban Catalonia

BACKGROUND

We aim to assess whether time of day modified the treatment effect in the RACECAT trial (Direct Transfer to an Endovascular Center Compared to Transfer to the Closest Stroke Center in Acute Stroke Patients With Suspected Large Vessel Occlusion Trial), a cluster-randomized trial that did not demonstrate the benefit of direct transportation to a thrombectomy-capable center versus nearest local stroke center for patients with a suspected large vessel stroke triaged in nonurban Catalonia between March 2017 and June 2020.

METHODS

We performed a post hoc analysis of RACECAT to evaluate if the association between initial transport routing and functional outcome differed according to trial enrollment time: daytime (8:00 am-8:59 pm) and nighttime (9:00 pm-7:59 am). Primary outcome was disability at 90 days, as assessed by the shift analysis on the modified Rankin Scale score, in patients with ischemic stroke. Subgroup analyses according to stroke subtype were evaluated.

RESULTS

We included 949 patients with an ischemic stroke, of whom 258 patients(27%) were enrolled during nighttime. Among patients enrolled during nighttime, direct transport to a thrombectomy-capable center was associated with lower degrees of disability at 90 days (adjusted common odds ratio [acOR], 1.620 [95% CI, 1.020-2.551]); no significant difference between trial groups was present during daytime (acOR, 0.890 [95% CI, 0.680-1.163]; P _interaction=0.014). Influence of nighttime on the treatment effect was only evident in patients with large vessel occlusion(daytime, acOR 0.766 [95% CI, 0.548-1.072]; nighttime, acOR, 1.785 [95% CI, 1.024-3.112] ; P _interaction<0.01); no heterogeneity was observed for other stroke subtypes (P _interaction>0.1 for all comparisons). We observed longer delays in alteplase administration, interhospital transfers, and mechanical thrombectomy initiation during nighttime in patients allocated to local stroke centers.

CONCLUSIONS

Among patients evaluated during nighttime for a suspected acute severe stroke in non-urban areas of Catalonia, direct transport to a thrombectomy-capable center was associated with lower degrees of disability at 90 days. This association was only evident in patients with confirmed large vessel occlusion on vascular imaging. Time delays in alteplase administration and interhospital transfers might mediate the observed differences in clinical outcome.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02795962.

Artificial Intelligence-Assisted Software Significantly Decreases All Workflow Metrics for Large Vessel Occlusion Transfer Patients, within a Large Spoke and Hub System

INTRODUCTION

Artificial intelligence (AI) software is increasingly applied in stroke diagnostics. Viz LVO (large vessel occlusion) is an AI-based software that is FDA-approved for LVO detection in CT angiography (CTA) scans. We sought to investigate differences in transfer times (from peripheral [spoke] to central [hub] hospitals) for LVO patients between spoke hospitals that utilize Viz LVO and those that do not.

METHODS

In this retrospective cohort study, we used our institutional database to identify all suspected/confirmed LVO-transferred patients from spokes (peripheral hospitals) within and outside of our healthcare system, from January 2020 to December 2021. The "Viz-transfers" group includes all LVO transfers from spokes within our system where Viz LVO is readily available, while the "Non-Viz-transfers" group (control group) is comprised of all LVO transfers from spokes outside our system, without Viz LVO. Primary outcome included all available time metrics from peripheral CTA commencement.

RESULTS

In total, 78 patients required a transfer. Despite comparable peripheral hospital door to peripheral hospital CTA times (20.5 [24.3] vs. 32 [45] min, p = 0.28) and transfer (spoke to hub) time (23 [18] vs. 26 [13.5], p = 0.763), all workflow metrics were statistically significantly shorter in the Viz-transfers group. Peripheral CTA to interventional neuroradiology team notification was 12 (16.8) versus 58 (59.5), p < 0.001, and peripheral CTA to peripheral departure was 91.5 (37) versus 122.5 (68.5), p < 0.001. Peripheral arrival to peripheral departure was 116.5 (75.5) versus 169 (126.8), p = 0.002, and peripheral arrival to central arrival was 145 (62.5) versus 207 (97.8), p < 0.001. In addition, peripheral CTA to angiosuite arrival was 121 (41) versus 207 (92.5), p < 0.001, peripheral CTA to arterial puncture was 146 (53) versus 234 (99.8), p < 0.001, and peripheral CTA to recanalization was 198 (25) versus 253.5 (86), p < 0.001.

CONCLUSION

Within our spoke and hub system, Viz LVO significantly decreased all workflow metrics for patients who were transferred from spokes with versus without Viz.

Determinants of Infarct Core Growth During Inter-hospital Transfer for Thrombectomy

OBJECTIVE

Patients with acute ischemic stroke harboring a large vessel occlusion who present to primary stroke centers often require inter-hospital transfer for thrombectomy. We aimed to determine clinical and imaging factors independently associated with fast infarct growth (IG) during inter-hospital transfer.

METHODS

We retrospectively analyzed data from acute stroke patients with a large vessel occlusion transferred for thrombectomy from a primary stroke center to one of three French comprehensive stroke centers, with an MRI obtained at both the primary and comprehensive center before thrombectomy. Inter-hospital IG rate was defined as the difference in infarct volumes on diffusion-weighted imaging between the primary and comprehensive center, divided by the delay between the two MRI scans. The primary outcome was identification of fast progressors, defined as IG rate ≥5 mL/hour. The hypoperfusion intensity ratio (HIR), a surrogate marker of collateral blood flow, was automatically measured on perfusion imaging.

RESULTS

A total of 233 patients were included, of whom 27% patients were fast progressors. The percentage of fast progressors was 3% among patients with HIR < 0.40 and 71% among those with HIR ≥ 0.40. In multivariable analysis, fast progression was independently associated with HIR, intracranial carotid artery occlusion, and exclusively deep infarct location at the primary center (C-statistic = 0.95; 95% confidence interval [CI], 0.93-0.98). IG rate was independently associated with good functional outcome (adjusted OR = 0.91; 95% CI, 0.83-0.99; P = 0.037).

INTERPRETATION

Our findings show that a HIR > 0.40 is a powerful indicator of fast inter-hospital IG. These results have implication for neuroprotection trial design, as well as informing triage decisions at primary stroke centers. ANN NEUROL 2023.

Endovascular treatment for ischemic stroke patients with and without atrial fibrillation, and the effects of adjunctive pharmacotherapy: a narrative review

INTRODUCTION

Endovascular thrombectomy (EVT) is associated with good clinical outcomes in patients with ischemic stroke, but the impact of EVT on clinical outcomes in patients with ischemic stroke with and without atrial fibrillation (AF), and the effect of adjunctive pharmacological therapies with EVT, remains unclear.

AREAS COVERED

The goal of this narrative review is to provide an overview of studies which have examined: 1) associations between EVT and outcomes for patients following ischemic stroke, 2) associations between EVT and outcomes for patients following ischemic stroke with and without AF , including function, reperfusion, hemorrhage, and mortality, 3) the effect of adjunctive pharmacological therapies peri- and post-thrombectomy, and 4) integration of prehospital care on endovascular treatment outcomes.

EXPERT OPINION

There is little evidence from randomized controlled trials on the effect of AF on stroke outcomes following EVT and the safety and efficacy of AF treatment in the peri-EVT such as tirofiban or Intravenous thrombolysis with Non-vitamin K Antagonist Oral Anticoagulant. The available evidence from observational studies on AF and EVT outcomes is inconsistent, but factors such as procedural EVT devices, the center volume, clinician experience, stroke recognition, and inclusion criteria of studies have all been associated with poorer clinical outcomes. Enhancing the clinical network among prehospital and hospitals will facilitate direct transfer to EVT centers, reducing stroke onset to EVT time and optimizing stroke outcomes.

Thrombectomy-Capable Stroke Centre-A Key to Acute Stroke Care System Improvement? Retrospective Analysis of Safety and Efficacy of Endovascular Treatment in Cardiac Cathlab

The optimal structure of the acute ischaemic stroke treatment network is unknown and eagerly sought. To make it most effective, different treatment and transportation strategies have been developed and investigated worldwide. Since only a fraction of acute stroke patients with large vessel occlusion are treated, a new entity-thrombectomy-capable stroke centre (TCSC)-was introduced to respond to the growing demand for timely endovascular treatment. The purpose of this study was to present the early experience of the first 70 patients treated by mechanical means in a newly developed cardiac Cathlab-based TCSC. The essential safety and efficacy measures were recorded and compared with those reported in the invasive arm of the HERMES meta-analysis-the largest published dataset on the subject. We found no significant differences in terms of clinical and safety outcomes, such as early neurological recovery, level of functional independence at 90 days, symptomatic intracranial haemorrhage, parenchymal haematoma type 2, and mortality. These encouraging results obtained in the small endovascular centre may be an argument for the introduction of the TCSC into operating stroke networks to increase patient access to timely treatment and to improve clinical outcomes.

[Prehospital stroke treatment in German-speaking countries]

Background

The prognosis of stroke patients can be improved by adherence to clinical guidelines.

Objective

To analyse the current state of organisation of prehospital stroke treatment in Germany, Austria and Switzerland with a focus on guideline adherence.

Materials and methods

All medical directors of emergency medical services (MDEMS) in Germany (n = 178), Austria (n = 9) and Switzerland (n = 32) were invited to complete an anonymous online survey (unipark.com, Tivian XI GmbH, Cologne, Germany) which was available for 10 weeks from April-June 2020. Participants were asked for information regarding structural organisation, clinical treatment and strategic/tactical aspects.

Results

The survey was completed 69 times and 65 datasets were analysed (4 participants without MDEMS status): 73.8% (n = 48) were MDEMS from Germany, 15.4% (n = 10) from Switzerland and 10.8% from Austria (n = 7). The survey results show relevant differences in the infrastructure of and the approach to prehospital stroke treatment. Standard operating procedures for stroke treatment were in place in 93.3% (n = 61) of the EMS areas. Furthermore, 37% (n = 24) of the EMS areas differentiated between stroke with mild and severe symptoms and 15.4% (n = 10) used specific scores for the prehospital prediction of large vessel occlusion strokes (LVOS).

Conclusions

Our data highlight the heterogeneity of prehospital stroke treatment in Germany, Austria and Switzerland. Consistent use of appropriate scores for LVOS prediction and a higher adherence to recent clinical guideline in general are measures that should be taken to optimise the prehospital treatment of stroke patients.

The Benefit of a Complete over a Successful Reperfusion Decreases with Time

OBJECTIVE

Time from stroke onset to reperfusion (TSOR) is strongly associated with outcomes after endovascular treatment. A near-to-complete or complete reperfusion (modified Treatment in Cerebral Ischemia [mTICI] 2c-3) is associated with improved outcomes compared with a successful reperfusion (mTICI 2b). However, it is unknown whether this association remains stable as TSOR increases. Therefore, we sought to investigate the association between TSOR and outcomes according to the reperfusion status.

METHODS

We analyzed data from the Endovascular Treatment in Ischemic Stroke registry, a prospective, observational, multicentric study of acute ischemic stroke patients treated with endovascular treatment in 21 centers in France. We included patients with anterior occlusions (M1, internal carotid artery, tandem), with a known time of symptom onset. Outcomes were early neurological improvement at 24 hours and favorable outcome (modified Rankin Scale between 0 and 2) at 90 days.

RESULTS

Overall, 4,444 patients were analyzed. Compared with a mTICI 2b, a mTICI 2c-3 at 1 hour was associated with higher mean marginal probabilities of early neurological improvement (25.6%, 95% CI 11.7-39.5, p = 0.0003) and favorable outcome (15.2%, 95% CI 3.0-27.4, p = 0.0143), and progressively declined with TSOR. The benefit of a mTICI 2c-3 over a mTICI 2b was no longer significant regarding the rates of early neurological improvement and favorable outcome after a TSOR of 414 and 344 minutes, respectively.

INTERPRETATION

The prognostic value of a complete over a successful reperfusion progressively declined with time, and no difference regarding the rates of favorable outcome was observed between a complete and successful reperfusion beyond 5.7 hours. ANN NEUROL 2023.

Periprocedure Management of Blood Pressure After Acute Ischemic Stroke

The management of acute ischemic stroke primarily revolves around the timely restoration of blood flow (recanalization/reperfusion) in the occluded vessel and maintenance of cerebral perfusion through collaterals before reperfusion. Mechanical thrombectomy is the most effective treatment for acute ischemic stroke due to large vessel occlusions in appropriately selected patients. Judicious management of blood pressure before, during, and after mechanical thrombectomy is critical to ensure good outcomes by preventing progression of cerebral ischemia as well hemorrhagic conversion, in addition to optimizing systemic perfusion. While direct evidence to support specific hemodynamic targets around mechanical thrombectomy is limited, there is increasing interest in this area. Newer approaches to blood pressure management utilizing individualized cerebral autoregulation-based targets are being explored. Early efforts at utilizing machine learning to predict blood pressure treatment thresholds and therapies also seem promising; this focused review aims to provide an update on recent evidence around periprocedural blood pressure management after acute ischemic stroke, highlighting its implications for clinical practice while identifying gaps in current literature.

Access to Mechanical Thrombectomy for Stroke: Center Qualifications, Prehospital Management, and Geographic Disparities

Mechanical thrombectomy (MT) became the "gold-standard" treatment for most patients with acute ischemic stroke due to anterior circulation large vessel occlusion. With such a remarkable paradigm shift, it is important that this modality of treatment becomes widely and homogeneously available throughout the United States and other countries. Although the time window for MT is large (24 hours in selected patients), time is still a major determinant of outcome. Several variables are involved in achieving timely access of MT for the majority of the population: prehospital management systems, transportation models, in-hospital workflow organization, accreditation and infrastructure of centers, training of neurointervention professionals, and geographic distribution of centers. The current situation in the United States regarding MT access is marked by geographic and socioeconomic disparities. We provide an overview of current challenges and solutions in achieving more universal access to MT for the population.

Impact of inter-hospital transfer on outcomes of urgent cholecystectomy

BACKGROUND

This study used a national cohort to characterize the impact of inter-hospital transfer status on outcomes following nonelective cholecystectomy for cholecystitis.

METHODS

Nonelective cholecystectomies were identified using the 2016-2019 National Inpatient Sample. Multivariable models adjusting for patient and hospital characteristics were utilized to assess outcomes of interest.

RESULTS

Of an estimated 530,696 patients, 5.3% were transferred. Transferred patients were older, more often male, and more likely to report income in the 0^th-25th percentile, compared to others. After adjustment, transfer was associated with increased odds of infectious complications (AOR 1.31, 95%CI 1.06-1.60) and non-home discharge (AOR 1.59, 95%CI 1.45-1.74), but not mortality. Transfer was linked to a $600 cost decrement at the operating hospital (95%CI -$880-330).

CONCLUSIONS

Transfer status is associated with greater postoperative infection, but not mortality. Given that disparities may play a role in transfer decisions, more work must be done to identify transfer drivers and improve patient outcomes.

Spoke-administered thrombolysis improves large vessel occlusion early recanalization: the real-world experience of a large academic hub-and-spoke telestroke network

Introduction

Intravenous thrombolysis (IVT) prior to mechanical thrombectomy (MT) for large vessel occlusion (LVO) stroke is increasingly controversial. Recent trials support MT without IVT for patients presenting directly to MT-capable "hub" centers. However, bypassing IVT has not been evaluated for patients presenting to IVT-capable "spoke" hospitals that require hub transfer for MT. A perceived lack of efficacy of IVT to result in LVO early recanalization (ER) is often cited to support bypassing IVT, but ER data for IVT in patients that require interhospital transfer is limited. Here we examined LVO ER rates after spoke-administered IVT in our hub-and-spoke stroke network.

Methods

Patients presenting to 25 spokes before hub transfer for MT consideration from 2018-2020 were retrospectively identified from a prospectively maintained database. Inclusion criteria were pre-transfer CTA-defined LVO, ASPECTS ≥6, and post-transfer repeat vessel imaging.

Results

Of 167 patients, median age was 69 and 51% were female. 76 received spoke IVT (+spokeIVT) and 91 did not (-spokeIVT). Alteplase was the only IVT used in this study. Comorbidities and NIHSS were similar between groups. ER frequency was increased 7.2-fold in +spokeIVT patients [12/76 (15.8%) vs. 2/91 (2.2%), P<0.001]. Spoke-administered IVT was independently associated with ER (aOR=11.5, 95% CI=2.2,99.6, p<0.05) after adjusting for timing of last known well, interhospital transfer, and repeat vessel imaging. Interval NIHSS was improved in patients with ER (median -2 (IQR -6.3, -0.8) vs. 0 (-2.5, 1), p<0.05).

Conclusion

Within our network, +spokeIVT patients had a 7.2-fold increased ER relative likelihood. This real-world analysis supports IVT use in eligible patients with LVO at spoke hospitals before hub transfer for MT.

Mothership vs. drip-and-ship: evaluation of initial treatment strategies for acute ischemic stroke in a well-developed network of specialized hospitals

PURPOSE

Two strategies of initial patient care exist in endovascular thrombectomy (ET) depending on the site of initial admission: the mothership (MS) and drip-and-ship (DnS) principles. This study compares both strategies in regard to patient outcome in a local network of specialized hospitals.

METHODS

Two-hundred-and-two patients undergoing ET in anterior circulation ischemic stroke between June 2016 and May 2018 were enrolled. Ninety two patients were directly admitted to our local facility (MS), One-hundred-and-ten were secondarily referred to our facility. Group comparisons between admission strategies in three-months modified Rankin Scale (mRS), Maas Score and Alberta-Stroke-Program-Early-computed-tomography-score (ASPECTS), National-Institutes-of-Health-Stroke-Scale (NIHSS), age and onset-to-recanalization-time were performed. Correlation between admission strategy and mRS was calculated. A binary logistic regression model was computed including mRS as dependent variable.

RESULTS

There were neither significant group differences in three-months mRS between MS and DnS nor significant correlations. Patients tended to achieve a better outcome with DnS. Collateralization status differed between MS and DnS (p = 0.003) with better collateralization in DnS. There were no significant group differences in NIHSS or ASPECTS but in onset-to-recanalization-time (p < 0.001) between MS and DnS. Binary logistic regression showed a high explanation of variance of mRS but no significant results for admission strategy.

CONCLUSIONS

Functional outcome in patients treated with ET is comparable between the MS and DnS principles. Tendentially better outcome in the DnS subgroup may be explained by selection bias due to a higher willingness to apply ET in patients with worse baseline conditions (e.g. worse collateralization), if patients undergoing MS are already on site.

Modeling optimal patient transport in a stroke network capable of remote telerobotic endovascular therapy

BACKGROUND

Telerobotic endovascular therapy (EVT) has the potential to decrease time to treatment and expand existing networks of care to more rural populations. It is currently unclear how its implementation would impact existing stroke networks.

METHODS

Conditional probability models were generated to predict the probability of excellent outcome for patients with suspected large vessel occlusion (LVO). A baseline stroke network was created for California using existing intravenous thrombolysis (IVT) centers and comprehensive stroke centers (CSCs) capable of IVT and EVT. Optimal transport decisions and catchment areas were generated for the baseline model and three hypothetical scenarios through conversion of IVT centers at various distances from a CSC into centers capable of telerobotic EVT [i.e., hospitals ≥15 and <50 miles from a CSC were converted (Scenario 1), ≥50 and <100 miles (Scenario 2), and ≥100 miles (Scenario 3)]. Procedural times and success rates were varied systematically.

RESULTS

Telerobotic EVT centers decreased median travel time for LVO patients in all three scenarios. The estimated number of robotically treated LVOs per year in Scenarios 1, 2, and 3 were 2,172, 740, and 212, respectively. Scenario 1 (15-50 miles) was the most sensitive to robotic time delay and success rate, but all three scenarios were more sensitive to decreases in procedural success rate compared to time delay.

CONCLUSIONS

Telerobotic EVT has the potential to improve care for stroke patients outside of major urban centers. Compared to procedural time delays in robotic EVT, a decrease in procedural success rate would not be well tolerated.

Drip and Ship versus Mothership Model in the Middle Cerebral Artery Stroke: A Propensity-Matched Real-World Analysis Through National Inpatient Sample Data

BACKGROUND

The superiority of mechanical thrombectomy and intravenous thrombolysis versus intravenous thrombolysis alone for acute ischemic stroke caused by large vessel occlusions has been established. This treatment can be organized into 2 models: drip and ship (DS) versus mothership (MS). We analyzed the National Inpatient Sample (NIS) data to compare the outcomes between these models in real-world settings.

METHODS

NIS data were queried for 2017-2018 and propensity matching was used to match the differences. Outcomes for each group (disability at discharge and procedural complications) were compared.

RESULTS

A total of 1226 patients were included in analysis (DS, n = 540; MS, n = 686) and groups were matched with respect to age, gender, and comorbidities. A total of 930 patients were included in the final analysis after propensity matching (DS, n = 465, MS, n = 465). The mean age in the DS group was 68.9 years (standard deviation [SD], 14.7) and 69.4 years (SD, 14) in the MS group (P = 0.752). The mean National Institutes of Health Stroke Scale score was 16.75 (SD, 6.07) in the DS group and 16.54 (SD, 5.99) in the MS group (P = 0.478). At discharge, minimal disability was noted in 22.4% in the DS group versus 26.2% in the MS group (P = 0.293). In-hospital mortality was lower in the MS group (8.8% vs. 7.1%; P = 0.32). The intracerebral hemorrhage (ICH) and intraventricular hemorrhage (IVH) rates were higher in the DS group (ICH, 24.3% vs. 18.7%; IVH, 2.4% vs. 0.9%) (ICH, P = 0.038; IVH, P = 0.068).

CONCLUSIONS

Analyzing the efficacy and safety profile of DS versus MS models with the NIS database showed a trend toward better discharge outcomes and lower mortality for the MS group, although it did not reach statistical significance.

Efficacy of Emergency Room Skip Strategy in Patients Transferred for Mechanical Thrombectomy

Objective

Time to recanalization is directly linked to cerebral infarction prognosis. However, patients transferred from another hospital take longer to arrive than those transported directly. To minimize time to recanalization, the emergency room (ER) skip strategy for hospital transfers was executed and reviewed.

Methods

From April 2019, patients transferred from another hospital for mechanical thrombectomy were carried into the angio-suite using emergency service stretchers. Results for these patients (ER skip group) were compared with those for patients transported directly to our hospital (Direct group).

Results

Among 108 cases in 32 months, 99 patients (91.7%) had major cerebral artery occlusion and underwent endovascular treatment. No differences in age, baseline National Institutes of Health Stroke Scale score, effective recanalization rate, or proportion of posterior circulation cases were seen between groups. The ER skip group (26 patients) showed significantly longer median time from onset to arrival (240 vs. 120 min; p = 0.0001) and significantly shorter median time from arrival to groin puncture (11 vs. 69 min; p = 0.0000). No significant differences were evident in time from groin puncture to recanalization (39 vs. 45 min), time from onset to recanalization (298 vs. 244 min), or rate of modified Rankin Scale score 0-2 after 90 days (42.3% vs. 32.9%). Median time from alarm to recanalization (266 vs. 176 min; p = 0.0001) was significantly longer in the ER skip group. Door-to-puncture (DTP) time for the Direct group gradually fell as the number of cases increased, reaching 40 min by the end of study period. In contrast, DTP time for the ER skip group remained extremely short and did not change further. The proportion of patients who underwent both CT and MRI before endovascular treatment was significantly lower in the Direct group (30.1%) than in the ER skip group (57.7%). In the ER skip group, median length of stay in the primary hospital was 119 min, and the median duration of interhospital transfer was 16 min.

Conclusion

The ER skip strategy for patients transferred with large vessel occlusion achieved favorable outcomes comparable to that for direct transport cases. Direct transport to a thrombectomy-capable stroke center remains ideal, however, because the time to intervention is improving for direct transport cases each year.

ELECTRA-STROKE: Electroencephalography controlled triage in the ambulance for acute ischemic stroke—Study protocol for a diagnostic trial

Background

Endovascular thrombectomy (EVT) is the standard treatment for large vessel occlusion stroke of the anterior circulation (LVO-a stroke). Approximately half of EVT-eligible patients are initially presented to hospitals that do not offer EVT. Subsequent inter-hospital transfer delays treatment, which negatively affects patients' prognosis. Prehospital identification of patients with LVO-a stroke would allow direct transportation of these patients to an EVT-capable center. Electroencephalography (EEG) may be suitable for this purpose because of its sensitivity to cerebral ischemia. The hypothesis of ELECTRA-STROKE is that dry electrode EEG is feasible for prehospital detection of LVO-a stroke.

Methods

ELECTRA-STROKE is an investigator-initiated, diagnostic study. EEG recordings will be performed in patients with a suspected stroke in the ambulance. The primary endpoint is the diagnostic accuracy of the theta/alpha ratio for the diagnosis of LVO-a stroke, expressed by the area under the receiver operating characteristic (ROC) curve. EEG recordings will be performed in 386 patients.

Discussion

If EEG can be used to identify LVO-a stroke patients with sufficiently high diagnostic accuracy, it may enable direct routing of these patients to an EVT-capable center, thereby reducing time-to-treatment and improving patient outcomes.

Clinical trial registration

ClinicalTrials.gov, identifier: NCT03699397.

Reducing delay to endovascular reperfusion after relocating a thrombolysis unit

Background and aims

Functional outcome following mechanical thrombectomy (MT) in patients with acute ischemic stroke and large vessel occlusion is time-dependent and worsens with increasing delay. Time to endovascular reperfusion is potentially modifiable with changes in organizational structure. We investigated the changes in time to reperfusion of relocating the intravenous thrombolysis (IVT) services from a non-MT center to a MT-capable center.

Methods

We present an observational, consecutive, retrospective, single-center cohort study of 253 stroke patients treated with MT, 2017–2019. The observation period was divided into before and after the relocation of IVT services in 2018, period 1 and period 2, respectively. The two hospitals were located 13 km apart in an urban area, and following the relocation, IVT was administered at the MT-capable center. Time metrics were registered and divided into two main intervals, namely, ambulance departure from stroke onset location to imaging (ambulance-imaging) and imaging to reperfusion (imaging-reperfusion). The interval imaging-reperfusion included inter-hospital transfer to the MT-capable center in period 1. The association of the imaging-reperfusion duration and functional outcome at 90 days was analyzed using ordinal logistic regression.

Results

No significant change in ambulance-imaging was observed from a median of 27 min (interquartile range [IQR] 22–37) in period 1 to 30 min (IQR 23–40) in period 2, p = 0.19, while the median time of imaging-reperfusion decreased from 173 min (IQR 137–230) to 114 min (IQR 84–152), p < 0.001. The largest absolute time reduction from imaging to reperfusion was seen from imaging to arrival at the angio suite from 89 min (IQR 76–111) to 42 min (IQR 28–63), p < 0.001, which included inter-hospital transfer in period 1. In multivariate analysis, every 10 min of increased delay from imaging to reperfusion was associated with poorer functional outcome with an adjusted odds ratio of 0.95 (95% CI: 0.95–0.98), p < 0.001.

Conclusion

Relocation of IVT services to an MT-capable center was the main cause of reduced time to reperfusion for patients treated with MT and was implemented without affecting prehospital transportation time. These results suggest that patient outcome can be improved by optimizing the organization of IVT and MT services in urban areas.

Factors associated with delayed hospital presentation for patients with acute stroke in Makkah: A cross-sectional study

Despite the recent advancements in the treatment of acute ischemic stroke, the delayed patient arrival to emergency department or hospital serve as crucial factor for the selection of appropriate intervention program. This study was aimed to identify factors associated with late hospital arrival for patients with acute ischemic stroke in Makkah, Saudi Arabia. A prospective cross-sectional study was carried out at Al-Noor Specialist Hospital among 98 enrolled patients with the mean age of 60.4 ± 10.3 years over the period of March 2019 and June 2019. The data were collected through review of patient records and interview of patients and attendants. Fifty-four of these (55%) presented early (within 4.5 hours) and 44 (45%) presented late (after 4.5 hours). Factor associated with late arrival included low educational level (P = .01) and unemployment status (P = .033). The relationship between time of presentation and computed tomography findings showed statis,tically significant relationship between the former and early computed tomography findings (P = .017). A statistically significant relationship between time of presentation and knowledge of stroke was also observed (P = .013). Increased public awareness is important in order to minimize the time between stroke onset and emergency room presentation.

Endovascular treatment for ischemic stroke with the drip-and-ship model—Insights from the German Stroke Registry

Background

Endovascular therapy (EVT) in acute ischemic stroke has been widely established. Globally, stroke patients are transferred either directly to a thrombectomy center (DC) or a peripheral stroke unit with a “drip-and-ship” (DS) model. We aimed to determine differences between the DS and DC paradigms after EVT of acute stroke patients with large-vessel-occlusion (LVO) in the database of the German Stroke Registry (GSR).

Methods

We performed a retrospective analysis of GSR patients between June 2015 and December 2019 in 23 German centers. Primary outcome was an ordinal shift analysis of modified Rankin Scale (mRS) 90 days after index event. Secondary endpoints included time from symptom onset to recanalization and complications. Tertiary endpoint was the association of imaging strategies in DS admissions with outcome.

Results

2,813 patients were included in the DS and 3,819 in the DC group. After propensity score matching mRS after 90 days was higher in DS than DC admissions (OR 1.26; 95%-CI 1.13–1.40). Time from symptom-onset to flow-restoration was shorter in DC than DS (median 199.0 vs. 298.0 min; p < 0.001). DS patients undergoing magnetic resonance imaging (MRI; n=183) before EVT had a lower 90-day mRS than without (n = 944) (OR 0.63; 95%-CI 0.45–0.88). ASPECTS assessed on MRI correlated with 90-day mRS (ρ = −0.326; p < 0.001).

Conclusions

Clinical outcome was worse for EVT-eligible patients in the DS setting, even though patients were in a better state of health prior to stroke. A potentially mutable factor was the time delay of 99 min from symptom-onset to successful recanalization. Performing MRI before thrombectomy was associated with good outcome and MRI-ASPECTS was negatively correlated with mRS after 90 days.

Prehospital stroke mimics in the Stockholm Stroke Triage System

Introduction

In 2017, Stockholm implemented a new prehospital stroke triage system (SSTS) directing patients with a likely indication for thrombectomy to the regional comprehensive stroke center (CSC) based on symptom severity and teleconsultation with a physician. In Stockholm, 44% of patients with prehospital code stroke have stroke mimics. Inadvertent triage of stroke mimics to the CSC could lead to inappropriate resource utilization.

Aims

To compare the characteristics between (1) triage-positive stroke mimics and stroke (TP mimics and TP stroke) and (2) triage-negative stroke mimics and stroke (TN mimics and TN stroke) and to (3) compare the distribution of stroke mimic diagnoses between triage-positive and triage-negative cases.

Methods

This prospective observational study collected data from October 2017 to October 2018, including 2,905 patients with suspected stroke who were transported by code-stroke ambulance to a Stockholm regional hospital. Patients directed to the CSC were defined as triage-positive. Those directed to the nearest stroke center were defined as triage-negative.

Results

Compared to individuals with TP stroke (n = 268), those with TP mimics (n = 55, median 64 vs. 75 years, P < 0.001) were younger and had lower NIHSS score (median 7 vs. 15, P < 0.001). Similarly, those with TN mimics (n = 1,221) were younger than those with TN stroke (n = 1,361, median 73 vs. 78 years, P < 0.001) and had lower NIHSS scores (median 2 vs. 4, P < 0.001). Functional paresis was more common in those with TP mimics than in those with TN mimics, 18/55 (32.7%) vs. 82/1,221 (6.7%), P < 0.001. Systemic infection was less common in those with TP mimics than in those with TN mimics, 1/55 (1.8%) vs. 160/1,221 (13.1%), P < 0.011. There was a trend toward “syncope, hypotension, or other cardiovascular diagnosis” being less common in those with TP mimics than in those with TN mimics, 1/55 (1.8%) vs. 118/1,221 (9.7%), P < 0.055.

Conclusions

In the SSTS, those with triage-positive and triage-negative stroke mimics were younger and had less severe symptoms than patients with stroke. All patients with TP mimics who had hemiparesis but overall exhibited less severe symptoms against true stroke but more severe symptoms than those with TN mimics were triaged to the nearest hospital. Over-triage of functional paresis to the CSC was relatively common. Meanwhile, a large majority of cases with minor symptoms caused by stroke mimics was triaged correctly by the SSTS to the nearest stroke center.

Impact of interhospital transfer vs. direct admission on acute ischemic stroke patients: A subset analysis of the COMPLETE registry

Background

Efficacy of thrombectomy treatment in acute ischemic stroke large vessel occlusion (AIS-LVO) patients is time dependent. Direct admission to thrombectomy centers (vs. interhospital transfer) may reduce time to treatment and improve outcomes. In this subset analysis of the COMPLETE registry, we compared outcomes between direct to thrombectomy center (Direct) vs. transfer from another hospital to thrombectomy center (Transfer) in AIS-LVO patients treated with aspiration thrombectomy.

Methods

COMPLETE was a prospective, international registry that enrolled patients from July 2018 to October 2019, with a 90-day follow-up period that was completed in January 2020. Imaging findings and safety events were adjudicated by core lab and independent medical reviewers, respectively. Pre-defined primary endpoints included post-procedure angiographic revascularization (mTICI ≥2b), 90-day functional outcome (mRS 0–2), and 90-day all-cause mortality. Planned collections of procedural time metrics and outcomes were used in the present post-hoc analysis to compare outcomes between transfer and direct patient cohorts.

Results

Of 650 patients enrolled, 343 were transfer [52.8% female; mean (SD) age, 68.2 (13.9) years], and 307 were direct [55.4% female; 68.5 (14.5) years] admit. Median onset-to-puncture time took longer in the transfer vs. direct cohort (5.65 vs. 3.18 h: 2.33 h difference, respectively; p < 0.001). There was no significant difference in successful revascularization rate, mTICI ≥2b (88.3 and 87.3%), sICH at 24 h (3.8 and 3.9%), median length of hospital stay (7 and 6 days), and 90-day mortality (16.9 and 14.0%) between transfer vs. direct patients, respectively. However, achieving 90-day functional independence was less likely in transfer compared with direct patients (mRS 0–2 was 50.3 vs. 61.7%, p = 0.0056).

Conclusions

In the COMPLETE registry, direct to thrombectomy center was associated with significantly shorter onset-to-puncture times, and higher rates of good clinical outcome across different geographies. Additional research should focus on AIS-LVO detection to facilitate direct routing of patients to appropriate treatment centers.

Clinical trial registration

https://clinicaltrials.gov (Unique identifier: NCT03464565).

Acute Ischemic Stroke Comorbid with Type 2 Diabetes: Long-Term Prognosis Determinants in a 36-Month Prospective Study for Personalized Medicine

Ischemic stroke (IS) is often comorbid with type 2 diabetes mellitus (T2DM) wherein the determinants of long-term outcomes, beyond the acute stroke phase, are not adequately known. This study identified the determinants of long-term outcomes for diabetic IS patients through a prospective nested case-control study in 624 patients treated with conservative measures (38.60% females, mean age: 63.85 years). After 36-month follow-up, 117 (18.8%) patients with poor outcome were enrolled in the case group. The poor outcome was defined with a modified Rankin Scale (mRS) score ≥3. Meanwhile, 374 (59.9%) patients with good outcome, defined as (mRS score <3), were included in the control group. Patients who died (n = 32) or lost to follow-up (n = 101) were excluded in analysis. Poor prognostic outcome was positively associated with (1) the pulse rate at admission, (2) diastolic blood pressure (DBP), and (3) fasting blood glucose (FBG) during follow-up, whereas physical activity and lipid-lowering treatment during follow-up were negatively associated. Importantly, a forecasting model with these indicators distinguished the patients with good versus poor outcomes with 70.1% sensitivity and 73.5% specificity. Health care professionals and laboratory medicine scholars may want to monitor an increase in DBP and FBG during follow-up, as well as physical activity and lipid-lowering treatment, in relationship to the prognosis of IS with comorbid T2DM after conservative therapies. The proposed predictive model for personalized/precision medicine requires field testing in independent studies, and might help risk stratification with theranostic tests for patients with acute IS who also have a diagnosis of T2DM.

Cincinnati Prehospital Stroke Scale Implementation of an Urban County Severity-Based Stroke Triage Protocol: Impact and Outcomes on a Comprehensive Stroke Center

BACKGROUND AND PURPOSE

Screening scales are recommended to assist field-based triage of acute stroke patients to designated stroke centers. Cincinnati prehospital stroke scale (CPSS) is a commonly used prehospital stroke screening tool and has been validated to identify large vessel occlusion (LVO). This study addresses the impact of county-based CPSS implementation to triage suspected LVO patients to a comprehensive stroke center (CSC).

MATERIALS AND METHODS

Dekalb County in Atlanta, Georgia, implemented CPSS-based protocol with score of 3 and last seen normal time < 24 h mandating transfer to the nearest CSC if the added bypass time was <15 min. Frequency of stroke codes, LVO, IV-tPA use, and thrombectomy treatment were compared six months before and after protocol change (November 1, 2020).

RESULTS

During the study period, 907 stroke patients presented to the CSC by EMS, including 289 (32%) with CPSS score 3. There was an increase in monthly ischemic stroke volume (pre-16 ± 2 vs.19 ± 3 p = 0.03), LVO (pre-4.3 ± 1.7 vs. post-7.0 ± 2.4; p = 0.03), EVT (pre-15% vs. post-30%; p = 0.001), without significant increase in stroke mimic volume or delay in mean time from last seen normal to IV-tPA (pre-165 ± 66, post-158 ± 49 min; p = 0.35). CPSS score 3 was associated with increased likelihood of LVO diagnosis (OR 8.5, 95% CI 5.0-14.4; p = 0.001) and decreased the likelihood of stroke mimics (OR 0.66, 95% CI 0.50-0.88; p = 0.004).

CONCLUSION

CPSS is a quick, easy to implement, and reliable prehospital severity scale for EMS to triage LVO to CSC without delaying IV-tPA treatment or significantly increasing stroke mimics.

Large vessel occlusion prediction scales provide high negative but low positive predictive values in prehospital suspected stroke patients

Introduction

We studied a registry of Emergency Medical Systems (EMS) identified prehospital suspected stroke patients brought to an academic endovascular capable hospital over 1 year to assess the prevalence of disease and externally validate large vessel occlusion (LVO) stroke prediction scales with a focus on predictive values.

Methods

All patients had last known well times within 6 hours and a positive prehospital Cincinnati Prehospital Stroke Scale. LVO prediction scale scores were retrospectively calculated from emergency department arrival National Institutes of Health Stroke Scale scores. Final diagnoses were determined by chart review. Prevalence and diagnostic performance statistics were calculated. We prespecified analyses to identify scale thresholds with positive predictive values (PPVs) ≥80% and negative predictive values (NPVs) ≥95%. A secondary analysis identified thresholds with PPVs ≥50%.

Results

Of 220 EMS transported patients, 13.6% had LVO stroke, 15.9% had intracranial haemorrhage, 20.5% had non-LVO stroke and 50% had stroke mimic diagnoses. LVO stroke prevalence was 15.8% among the 184 diagnostic performance study eligible patients. Only Field Assessment Stroke Triage for Emergency Destination (FAST-ED) ≥7 had a PPV ≥80%, but this threshold missed 83% of LVO strokes. FAST-ED ≥6, Prehospital Acute Severity Scale =3 and Rapid Arterial oCclusion Evaluation ≥7 had PPVs ≥50% but sensitivities were <50%. Several standard and lower alternative scale thresholds achieved NPVs ≥95%, but false positives were common.

Conclusions

Diagnostic performance tradeoffs of LVO prediction scales limited their ability to achieve high PPVs without missing most LVO strokes. Multiple scales provided high NPV thresholds, but these were associated with many false positives.

Portable stroke detection devices: a systematic scoping review of prehospital applications

BACKGROUND

The worldwide burden of stroke remains high, with increasing time-to-treatment correlated with worse outcomes. Yet stroke subtype determination, most importantly between stroke/non-stroke and ischemic/hemorrhagic stroke, is not confirmed until hospital CT diagnosis, resulting in suboptimal prehospital triage and delayed treatment. In this study, we survey portable, non-invasive diagnostic technologies that could streamline triage by making this initial determination of stroke type, thereby reducing time-to-treatment.

METHODS

Following PRISMA guidelines, we performed a scoping review of portable stroke diagnostic devices. The search was executed in PubMed and Scopus, and all studies testing technology for the detection of stroke or intracranial hemorrhage were eligible for inclusion. Extracted data included type of technology, location, feasibility, time to results, and diagnostic accuracy.

RESULTS

After a screening of 296 studies, 16 papers were selected for inclusion. Studied devices utilized various types of diagnostic technology, including near-infrared spectroscopy (6), ultrasound (4), electroencephalography (4), microwave technology (1), and volumetric impedance spectroscopy (1). Three devices were tested prior to hospital arrival, 6 were tested in the emergency department, and 7 were tested in unspecified hospital settings. Median measurement time was 3 minutes (IQR: 3 minutes to 5.6 minutes). Several technologies showed high diagnostic accuracy in severe stroke and intracranial hematoma detection.

CONCLUSION

Numerous emerging portable technologies have been reported to detect and stratify stroke to potentially improve prehospital triage. However, the majority of these current technologies are still in development and utilize a variety of accuracy metrics, making inter-technology comparisons difficult. Standardizing evaluation of diagnostic accuracy may be helpful in further optimizing portable stroke detection technology for clinical use.

Safety and effectiveness of mechanical thrombectomy for acute ischemic stroke using single plane angiography

OBJECTIVES

Nearly all data on mechanical thrombectomy for acute ischemic stroke is based on procedures performed on biplane angiography systems. However, thrombectomy may be performed on single-plane systems in situations of triage or limited resources. We present the first US study comparing the safety and effectiveness of mechanical thrombectomy performed on single-plane vs. biplane systems.

METHODS AND METHODS

A retrospective review of a prospectively maintained database identified all patients treated with thrombectomy between July 2020 and July 2021 by a high-volume practice. Patients were dichotomized into those treated on single plane and biplane systems. Demographic, procedural, clinical and follow-up characteristics were compared.

RESULTS

Of the 246 patients treated with mechanical thrombectomy, 70 (33%) and 141 (66%) patients were treated on SP and BP systems, respectively. No significant differences were detected in follow-up 'good functional outcome' (mRS ≤ 2; SP 51% vs BP 43%, p = 0.14), successful recanalization (SP 87% vs BP 88%, p = 0.72), intra-procedural vascular injury (SP 3% vs BP 2%, p = 0.96), or time from groin puncture to reperfusion (SP 24 min vs BP 26 min, p = 0.58). Additionally, no significant differences were detected in peri-procedural complications, fluoroscopy times or total radiation. Patients treated on single plane systems required significantly more contrast.

CONCLUSIONS

Mechanical thrombectomy for acute ischemic stroke performed on single plane angiography systems is as safe and efficacious as when performed on biplane systems. Our results may have implications for increasing stroke care access, both domestically in underserved/rural areas and internationally when considering requirements for stroke care in lower-income countries.

Quality of Life in the First Year after Ischemic Stroke Treated with Acute Revascularization Therapy

(1) Background: we aimed to describe the disease-specific quality of life (QoL) of ischemic stroke patients treated with acute revascularization therapy, its evolution from 6 months to 12 months, and associated factors. (2) Methods: QoL was assessed with the SS-QoL in consecutive patients treated with either intravenous thrombolysis (IVT) and/or mechanical thrombectomy (MT). Variables associated with QoL scores and its evolution were studied using multivariate mixed models, and interaction with time. Analyses were performed in four domains of SS-QoL: self-care, mobility, mood, and social roles. (3) Results: Among the 501 included patients (mean (sd) age 68.9 (14.5), 49% women), lower post-stroke QoL was independently related to lower level of school education, prestroke mRS > 2, and 24 h NIHSS score > 4. Independent predictors of unfavorable evolution of QoL over time were age <75 years (Mobility p = 0.0194 and Mood p = 0.0015), NIHSS score ≤ 4, (Self-care p = 0.0053 and Mood p = 0.0048), and modified Rankin Scale score ≤ 2 (Social roles, p = 0.0006). Revascularization therapy had no significant effect on the QoL scores, but patients treated with MT (alone or as bridging therapy) had significantly greater improvement in mobility score between 6 and 12 months than patients treated with IVT alone (p = 0.0072). (4) Conclusion: QoL evolution over one year had only slight variation and was associated with the modalities of acute treatment, age, and stroke severity.

Analysis and modelling of mistriage in the Stockholm stroke triage system

INTRODUCTION

The Stockholm Stroke Triage System (SSTS) is a prehospital triage system for detection of patients eligible for endovascular thrombectomy (EVT). Assessment of hemiparesis combined with ambulance-hospital teleconsultation is used to route patients directly to the thrombectomy centre. Some patients are not identified and require secondary transport for EVT (undertriage) while others taken to the thrombectomy centre do not undergo EVT (overtriage). The aims of this study were to characterize mistriaged patients, model for and evaluate alternative triage algorithms.

PATIENTS AND METHODS

Patients with suspected stroke transported by priority 1 ground ambulance between October 2017 and October 2018 (n = 2905) were included. Three triage algorithms were modelled using prehospital data. Decision curve analysis was performed to calculate net benefit (correctly routing patients for EVT without increasing mistriage) of alternative models vs SSTS.

RESULTS

Undertriage for EVT occurred in n = 35/2582 (1.4%) and overtriage in n = 239/323 (74.0%). Compared to correct thrombectomy triages, undertriaged patients were younger and had lower median NIHSS (10 vs 18), despite 62.9% with an M1 occlusion. In overtriaged patients, 77.0% had a stroke diagnosis (29.7% haemorrhagic). Hemiparesis and FAST items face and speech were included in all models. Decision curve analysis showed highest net benefit for SSTS for EVT, but lower for large artery occlusion (LAO) stroke.

DISCUSSION

Undertriaged patients had lower NIHSS, likely due to better compensated proximal occlusions. SSTS was superior to other models for identifying EVT candidates, but lacked information allowing comparison to other prehospital scales.

CONCLUSION

Using prehospital data, alternative models did not outperform the SSTS in finding EVT candidates.

Factors Affecting Interfacility Transport Intervals in Stroke Patients Transferred for Endovascular Therapy

Objective: To describe interfacility transfer (IFT) intervals, transfer vehicle type, and levels of care in patients with large vessel occlusion (LVO) strokes transferred for emergent endovascular therapy (EVT).Methods: We included all patients transferred by a single IFT agency in the state of Indiana from July 1, 2018 to December 1, 2020 to a comprehensive stroke center in Indianapolis for emergent EVT. Data were collected from the transfer center electronic medical records and matched to IFT and receiving hospital data.Results: Two hundred eighty-eight patients were included, of which 150 (52.0%) received EVT. The median call-to-needle interval (from call to the transfer center to EVT needle puncture) was 155.5 minutes (IQR 135.8-195.3). The median resource activation interval (call to the transfer center to IFT deployment) was 16 minutes (IQR 10-27 minutes); the median IFT response interval (call to IFT to arrival of the transferring unit) was 34 minutes (IQR 25-43 minutes); the median pre-transfer interval (call to the transfer center until departure from the sending hospital) was 60.4 minutes (IQR 47.1-72.6); and the median sending hospital interval at bedside was 25 minutes (IQR 20-30 minutes). Most patients (197, 68.4%) were sent via critical care rotor. Only 61 (21.2%) required interventions other than tissue plasminogen administration, such as titration of actively transfusing medications (e.g., nicardipine, propofol) (37 of 61, 59.7%), or intubation or ventilator management (25 of 61, 40.3%). Patients sent via critical care rotor had longer sending hospital intervals (26 minutes, IQR 22-32, vs 19 minutes, IQR 16-25; p < 0.001) but shorter transfer intervals than those sent via critical care ground.Conclusions: At longer distances, rotor transport saved significant time specifically in the total IFT interval of patients with LVO strokes. Emphasizing processes to reduce the resource activation interval and the sending hospital interval may help reduce the overall time-to-EVT.

Validation of a machine learning software tool for automated large vessel occlusion detection in patients with suspected acute stroke

PURPOSE

CT angiography (CTA) is the imaging standard for large vessel occlusion (LVO) detection in patients with acute ischemic stroke. StrokeSENS LVO is an automated tool that utilizes a machine learning algorithm to identify anterior large vessel occlusions (LVO) on CTA. The aim of this study was to test the algorithm's performance in LVO detection in an independent dataset.

METHODS

A total of 400 studies (217 LVO, 183 other/no occlusion) read by expert consensus were used for retrospective analysis. The LVO was defined as intracranial internal carotid artery (ICA) occlusion and M1 middle cerebral artery (MCA) occlusion. Software performance in detecting anterior LVO was evaluated using receiver operator characteristics (ROC) analysis, reporting area under the curve (AUC), sensitivity, and specificity. Subgroup analyses were performed to evaluate if performance in detecting LVO differed by subgroups, namely M1 MCA and ICA occlusion sites, and in data stratified by patient age, sex, and CTA acquisition characteristics (slice thickness, kilovoltage tube peak, and scanner manufacturer).

RESULTS

AUC, sensitivity, and specificity overall were as follows: 0.939, 0.894, and 0.874, respectively, in the full cohort; 0.927, 0.857, and 0.874, respectively, in the ICA occlusion cohort; 0.945, 0.914, and 0.874, respectively, in the M1 MCA occlusion cohort. Performance did not differ significantly by patient age, sex, or CTA acquisition characteristics.

CONCLUSION

The StrokeSENS LVO machine learning algorithm detects anterior LVO with high accuracy from a range of scans in a large dataset.

Travel time and distance for bypass and non-bypass routing of stroke patients in the USA

BACKGROUND

Endovascular thrombectomy is not available at all hospitals that offer intravenous thrombolysis, prompting debate regarding the preferred transport destination for acute ischemic stroke. This study aimed to quantify real-world travel time and distance of bypass and non-bypass transport models for large-vessel occlusion (LVO) and non-LVO stroke.

METHODS

This cross-sectional study included population data of census tracts in the contiguous USA from the 2014-2018 United States Census Bureau's American Community Survey, stroke (thrombolysis-capable) and thrombectomy-capable centers certified by a state or national body, and road network data from a mapping service. Census tracts were categorized by urbanization level. Data were retrieved from March to November 2020. Travel times and distances were calculated for each census tract to each of the following: nearest stroke center (nearest), nearest thrombectomy-capable center (bypass), and nearest stroke center then to the nearest thrombectomy-capable center (transfer). Population-weighted median and IQR were calculated nationally and by urbanization.

RESULTS

72 538 census tracts, 2388 stroke hospitals, and 371 thrombectomy-capable centers were included. Nationally, population-weighted median travel time for nearest and bypass routing was 11.7 min (IQR 7.7-19.3) and 26.4 min (14.8-55.1), respectively. For transfer routing, the population-weighted median travel times with 60 min, 90 min, and 120 min door-in-door-out times were 94.1 min (78.5-127.7), 124.1 min (108.5-157.7), and 154.1 min (138.4-187.6), respectively.

CONCLUSIONS

Bypass routing offers modest travel time benefits for LVO patients and incurs modest penalties for non-LVO patients. Differences are greatest in rural areas. A majority of Americans live in areas for which current guidelines recommend bypass.

Effect of Direct Transportation to Thrombectomy-Capable Center vs Local Stroke Center on Neurological Outcomes in Patients With Suspected Large-Vessel Occlusion Stroke in Nonurban Areas: The RACECAT Randomized Clinical Trial

IMPORTANCE

In nonurban areas with limited access to thrombectomy-capable centers, optimal prehospital transport strategies in patients with suspected large-vessel occlusion stroke are unknown.

OBJECTIVE

To determine whether, in nonurban areas, direct transport to a thrombectomy-capable center is beneficial compared with transport to the closest local stroke center.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, population-based, cluster-randomized trial including 1401 patients with suspected acute large-vessel occlusion stroke attended by emergency medical services in areas where the closest local stroke center was not capable of performing thrombectomy in Catalonia, Spain, between March 2017 and June 2020. The date of final follow-up was September 2020.

INTERVENTIONS

Transportation to a thrombectomy-capable center (n = 688) or the closest local stroke center (n = 713).

MAIN OUTCOMES AND MEASURES

The primary outcome was disability at 90 days based on the modified Rankin Scale (mRS; scores range from 0 [no symptoms] to 6 [death]) in the target population of patients with ischemic stroke. There were 11 secondary outcomes, including rate of intravenous tissue plasminogen activator administration and thrombectomy in the target population and 90-day mortality in the safety population of all randomized patients.

RESULTS

Enrollment was halted for futility following a second interim analysis. The 1401 enrolled patients were included in the safety analysis, of whom 1369 (98%) consented to participate and were included in the as-randomized analysis (56% men; median age, 75 [IQR, 65-83] years; median National Institutes of Health Stroke Scale score, 17 [IQR, 11-21]); 949 (69%) comprised the target ischemic stroke population included in the primary analysis. For the primary outcome in the target population, median mRS score was 3 (IQR, 2-5) vs 3 (IQR, 2-5) (adjusted common odds ratio [OR], 1.03; 95% CI, 0.82-1.29). Of 11 reported secondary outcomes, 8 showed no significant difference. Compared with patients first transported to local stroke centers, patients directly transported to thrombectomy-capable centers had significantly lower odds of receiving intravenous tissue plasminogen activator (in the target population, 229/482 [47.5%] vs 282/467 [60.4%]; OR, 0.59; 95% CI, 0.45-0.76) and significantly higher odds of receiving thrombectomy (in the target population, 235/482 [48.8%] vs 184/467 [39.4%]; OR, 1.46; 95% CI, 1.13-1.89). Mortality at 90 days in the safety population was not significantly different between groups (188/688 [27.3%] vs 194/713 [27.2%]; adjusted hazard ratio, 0.97; 95% CI, 0.79-1.18).

CONCLUSIONS AND RELEVANCE

In nonurban areas in Catalonia, Spain, there was no significant difference in 90-day neurological outcomes between transportation to a local stroke center vs a thrombectomy-capable referral center in patients with suspected large-vessel occlusion stroke. These findings require replication in other settings.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02795962.

Leukocytes in Cerebral Thrombus Respond to Large-Vessel Occlusion in a Time-Dependent Manner and the Association of NETs With Collateral Flow

Thrombus components are dynamically influenced by local blood flow and blood immune cells. After a large-vessel occlusion stroke, changes in the cerebral thrombus are unclear. Here we assessed a total of 206 cerebral thrombi from patients with ischemic stroke undergoing endovascular thrombectomy. The thrombi were categorized by time to reperfusion of <4 h (T4), 4–8 h (T4–8), and >8 h (T8). The cellular compositions in thrombus were analyzed, and relevant clinical features were compared. Both white blood cells and neutrophils were increased and then decreased in thrombus with time to reperfusion, which were positively correlated with those in peripheral blood. The neutrophil extracellular trap (NET) content in thrombus was correlated with the degree of neurological impairment of patients. Moreover, with prolonged time to reperfusion, the patients showed a trend of better collateral grade, which was associated with a lower NET content in the thrombus. In conclusion, the present results reveal the relationship between time-related endovascular immune response and clinical symptoms post-stroke from the perspective of thrombus and peripheral blood. The time-related pathological changes of cerebral thrombus may not be the direct cause for the difficulty in thrombolysis and thrombectomy. A low NET content in thrombi indicates excellent collateral flow, which suggests that treatments targeting NETs in thrombi might be beneficial for early neurological protection.

Comparisons of Prehospital Delay and Related Factors Between Acute Ischemic Stroke and Acute Myocardial Infarction

Background

Prehospital delay is an important contributor to poor outcomes in both acute ischemic stroke (AIS) and acute myocardial infarction (AMI). We aimed to compare the prehospital delay and related factors between AIS and AMI.

Methods and Results

We identified patients with AIS and AMI who were admitted to the 11 Korean Regional Cardiocerebrovascular Centers via the emergency room between July 2016 and December 2018. Delayed arrival was defined as a prehospital delay of >3 hours, and the generalized linear mixed‐effects model was applied to explore the effects of potential predictors on delayed arrival. This study included 17 895 and 8322 patients with AIS and AMI, respectively. The median value of prehospital delay was 6.05 hours in AIS and 3.00 hours in AMI. The use of emergency medical services was the key determinant of delayed arrival in both groups. Previous history, 1‐person household, weekday presentation, and interhospital transfer had higher odds of delayed arrival in both groups. Age and sex had no or minimal effects on delayed arrival in AIS; however, age and female sex were associated with higher odds of delayed arrival in AMI. More severe symptoms had lower odds of delayed arrival in AIS, whereas no significant effect was observed in AMI. Off‐hour presentation had higher and prehospital awareness had lower odds of delayed arrival; however, the magnitude of their effects differed quantitatively between AIS and AMI.

Conclusions

The effects of some nonmodifiable and modifiable factors on prehospital delay differed between AIS and AMI. A differentiated strategy might be required to reduce prehospital delay.

The Prehospital Stroke Score and telephone conference: A prospective validation

OBJECTIVES

The main aim of the study is to investigate the performance of a two-part stroke scale for screening and subsequent severity assessment combined with a telephone conference (teleconference).

MATERIALS AND METHODS

During a 6-month period, we prospectively tested the Prehospital Stroke Score (PreSS). PreSS part 1 is designed to identify stroke or TIA in a prehospital setting. PreSS part 2 is a stroke severity scale designed to identify large-vessel occlusion (LVO). PreSS was performed by emergency medical service (EMS) providers prior to a teleconference with a stroke neurologist.

RESULTS

Combined teleconference and PreSS part 1 were performed on 79.3% of all patients diagnosed with stroke/TIA, and 99.1% of the patients with positive scores were subsequently PreSS part 2 scored. PreSS part 1 and teleconference had a sensitivity to identify stroke/TIA of 89.3% (95% CI 85.7-92.2), specificity of 64.5% (95% CI 59.3-69.5), and an area under the curve (AUC) of 0.80 (95% CI 0.77-0.83). Regarding LVO, PreSS part 1 with teleconference recognized 96.7% (95% CI 88.7-99.6) of all cases as stroke. PreSS part 2 had a sensitivity of 55.7% (95% CI 42.4-68.5), specificity of 91.5% (95% CI 89.0-93.6), and AUC of 0.86 (95% CI 0.82-0.90) for identification of LVO.

CONCLUSIONS

PreSS was feasible and the sensitivity for stroke/TIA and LVO was high to moderate providing an overall high precision. Almost all LVO cases were ensured acute stroke admission. The high specificity for LVO could be useful for determining transfers strategies.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence when evaluating PreSS combined with teleconference.

Influence of Hospital Characteristics on Hospital Transfer Destinations for Patients With Stroke

BACKGROUND

Patients with stroke are frequently transferred between hospitals. This may have implications on the quality of care received by patients; however, it is not well understood how the characteristics of sending and receiving hospitals affect the likelihood of a transfer event. Our objective was to identify hospital characteristics associated with sending and receiving patients with stroke.

METHODS

Using a comprehensive statewide administrative dataset, including all 78 Massachusetts hospitals, we identified all transfers of patients with ischemic stroke between October 2007 and September 2015 for this observational study. Hospital variables included reputation (US News and World Report ranking), capability (stroke center status, annual stroke volume, and trauma center designation), and institutional affiliation. We included network variables to control for the structure of hospital-to-hospital transfers. We used relational event modeling to account for complex temporal and relational dependencies associated with transfers. This method decomposes a series of patient transfers into a sequence of decisions characterized by transfer initiations and destinations, modeling them using a discrete-choice framework.

RESULTS

Among 73 114 ischemic stroke admissions there were 7189 (9.8%) transfers during the study period. After accounting for travel time between hospitals and structural network characteristics, factors associated with increased likelihood of being a receiving hospital (in descending order of relative effect size) included shared hospital affiliation (5.8× higher), teaching hospital status (4.2× higher), stroke center status (4.3× and 3.8× higher when of the same or higher status), and hospitals of the same or higher reputational ranking (1.5× higher).

CONCLUSIONS

After accounting for distance and structural network characteristics, in descending order of importance, shared hospital affiliation, hospital capabilities, and hospital reputation were important factor in determining transfer destination of patients with stroke. This study provides a starting point for future research exploring how relational coordination between hospitals may ensure optimized allocation of patients with stroke for maximal patient benefit.

Optimizing Prehospital Stroke Systems of Care-Reacting to Changing Paradigms (OPUS-REACH): a pragmatic registry of large vessel occlusion stroke patients to create evidence-based stroke systems of care and eliminate disparities in access to stroke care

Background

Large vessel occlusion (LVO) strokes are best treated with rapid endovascular therapy (EVT). There are two routes that LVO stroke patients can take to EVT therapy when transported by EMS: primary transport (ambulance transports directly to an endovascular stroke center (ESC) or secondary transport (EMS transports to a non-ESC then transfers for EVT). There is no clear evidence which path to care results in better functional outcomes for LVO stroke patients. To find this answer, an analysis of a large, real-world population of LVO stroke patients must be performed.

Methods

A pragmatic registry of LVO stroke patients from nine health systems across the United States. The nine health systems span urban and rural populations as well as the spectrum of socioeconomic statuses. We will use univariate and multivariate analysis to explore the relationships between type of EMS transport, socioeconomic factors, and LVO stroke outcomes. We will use geographic information systems and spatial analysis to examine the complex movements of patients in time and space. To detect an 8% difference between groups, with a 3:1 patient ratio of primary to secondary transports, 95% confidence and 80% power, we will need approximately 1600 patients.

The primary outcome is the patients with modified Rankin Scale (mRS) ≤ 2 at 90 days. Subgroup analyses include patients who receive intravenous thrombolysis and duration of stroke systems. Secondary analyses include socioeconomic factors associated with poor outcomes after LVO stroke.

Discussion

Using the data obtained from the OPUS-REACH registry, we will develop evidence based algorithms for prehospital transport of LVO stroke patients. Unlike prior research, the OPUS-REACH registry contains patient-level data spanning from EMS dispatch to ninety day functional outcomes. We expect that we will find modifiable factors and socioeconomic disparities associated with poor outcomes in LVO stroke. OPUS-REACH with its breadth of locations, detailed patient records, and multidisciplinary researchers will design the optimal prehospital stroke system of care for LVO stroke patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02653-x.

A novel emergency medical services protocol to improve treatment time for large vessel occlusion strokes

In many systems, patients with large vessel occlusion (LVO) strokes experience delays in transport to thrombectomy-capable centers. This pilot study examined use of a novel emergency medical services (EMS) protocol to expedite transfer of patients with LVOs to a comprehensive stroke center (CSC). From October 1, 2020 to February 22, 2021, Indianapolis EMS piloted a protocol, in which paramedics, after transporting a patient with a possible stroke remained at the patient's bedside until released by the emergency department or neurology physician. In patients with possible LVO, EMS providers remained at the bedside until the clinical assessment and CT angiography (CTA) were complete. If indicated, the paramedics at bedside transferred the patient, via the same ambulance, to a nearby thrombectomy-capable CSC with which an automatic transfer agreement had been arranged. This five-month mixed methods study included case-control assessment of use of the protocol, number of transfers, safety during transport, and time saved in transfer compared to emergent transfers via conventional interfacility transfer agencies. In qualitative analysis EMS providers, and ED physicians and neurologists at both sending and receiving institutions, completed e-mail surveys on the process, and offered suggestions for process improvement. Responses were coded with an inductive content analysis approach. The protocol was used 42 times during the study period; four patients were found to have LVOs and were transferred to the CSC. There were no adverse events. Median time from decision-to-transfer to arrival at the CSC was 27.5 minutes (IQR 24.5-29.0), compared to 314.5 minutes (IQR 204.0-459.3) for acute non-stroke transfers during the same period. Major themes of provider impressions included: incomplete awareness of the protocol, smooth process, challenges when a stroke alert was activated after EMS left the hospital, greater involvement of EMS in patient care, and comments on communication and efficiency. This pilot study demonstrated the feasibility, safety, and efficiency of a novel approach to expedite endovascular therapy for patients with LVOs.

The Bigger the Better? Center Volume Dependent Effects on Procedural and Functional Outcome in Established Endovascular Stroke Centers

Background

Mechanical thrombectomy (MT) rates for the treatment of acute ischaemic stroke due to large vessel occlusion are steadily increasing, but are delivered in heterogenic settings. We aim to investigate effects of procedural load in centers with established MT-structures by comparing high- vs. low-volume centers with regard to procedural characteristics and functional outcomes.

Methods

Data from 5,379 patients enrolled in the German Stroke Registry Endovascular Treatment (GSR-ET) between June 2015 and December 2019 were compared between three groups: high volume: ≥180 MTs/year, 2,342 patients; medium volume: 135-179 MTs/year, 2,202 patients; low volume: <135 MTs/year, 835 patients. Univariate analysis and multiple linear and logistic regression analyses were performed to identify differences between high- and low-volume centers.

Results

We identified high- vs. low-volume centers to be an independent predictor of shorter intra-hospital (admission to groin puncture: 60 vs. 82 min, β = -26.458; p < 0.001) and procedural times (groin puncture to flow restoration: 36 vs. 46.5 min; β = -12.452; p < 0.001) after adjusting for clinically relevant factors. Moreover, high-volume centers predicted a shorter duration of hospital stay (8 vs. 9 days; β = -2.901; p < 0.001) and favorable medical facility at discharge [transfer to neurorehabilitation facility/home vs. hospital/nursing home/in-house fatality, odds ratio (OR) 1.340, p = 0.002]. Differences for functional outcome at 90-day follow-up were observed only on univariate level in the subgroup of primarily to MT center admitted patients (mRS 0-2 38.5 vs. 32.8%, p = 0.028), but did not persist in multivariate analyses.

Conclusion

Differences in efficiency measured by procedural times call for analysis and optimization of in-house procedural workflows at regularly used but comparatively low procedural volume MT centers.

Comparison of large vessel occlusion scales using prehospital patient reports

BACKGROUND

Prehospital identification of large vessel occlusion (LVO) holds significant potential to decrease the onset-to-treatment time. Several prehospital scales have been developed to identify LVO but data on their comparison has been limited. The aim of this study was to review the currently available prehospital LVO scales and compare their performance using prehospital data.

METHODS

All patients transported by ambulance using stroke code on a six-month period were enrolled into the study. The prehospital patient reports were retrospectively evaluated by two investigators using sixteen LVO scales identified by literature search and expert opinion. After the evaluation, the computed tomography angiography results were reviewed by a neuroradiologist to confirm or exclude LVO.

RESULTS

Sixteen different LVO scales met the predetermined study criteria and were selected for further comparison. Using them, a total of 610 evaluations were registered. The sensitivity of the scales varied between 8%-73%, specificity between 71%-97% and overall accuracy between 71%-87%. The areas under curve (AUC) varied between 0.61-0.80 for the whole scale range and 0.53%-0.74 for the scales' binary cut-offs. The Field Assessment Stroke Triage for Emergency Destination (FAST-ED) was the only scale with AUC > 0.8. Regarding scales' binary cut-offs, The FAST-ED (0.70), Gaze - Face Arm Speech Time (G-FAST) (0.74) and Emergency Medical Stroke Assessment (EMSA) (0.72) were the only scales with AUC > 0.7.

CONCLUSIONS

In a comparison of 16 different LVO scales, the FAST-ED, G-FAST and EMSA achieved the highest overall performance.

European Stroke Organisation (ESO) guidelines on mobile stroke units for prehospital stroke management

The safety and efficacy of mobile stroke units (MSUs) in prehospital stroke management has recently been investigated in different clinical studies. MSUs are ambulances equipped with a CT scanner, point-of-care lab, telemedicine and are staffed with a stroke specialised medical team. This European Stroke Organisation (ESO) guideline provides an up-to-date evidence-based recommendation to assist decision-makers in their choice on using MSUs for prehospital management of suspected stroke, which includes patients with acute ischaemic stroke (AIS), intracranial haemorrhage (ICH) and stroke mimics. The guidelines were developed according to the ESO standard operating procedure and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and aggregated data meta-analyses of the literature, assessed the quality of the available evidence and made specific recommendations. Expert consensus statements are provided where sufficient evidence was not available to provide recommendations based on the GRADE approach. We found moderate evidence for suggesting MSU management for patients with suspected stroke. The patient group diagnosed with AIS shows an improvement of functional outcomes at 90 days, reduced onset to treatment times and increased proportion receiving IVT within 60 min from onset. MSU management might be beneficial for patients with ICH as MSU management was associated with a higher proportion of ICH patients being primarily transported to tertiary care stroke centres. No safety concerns (all-cause mortality, proportion of stroke mimics treated with IVT, symptomatic intracranial bleeding and major extracranial bleeding) could be identified for all patients managed with a MSU compared to conventional care. We suggest MSU management to improve prehospital management of suspected stroke patients.

Team Prenotification Reduces Procedure Times for Patients With Acute Ischemic Stroke Due to Large Vessel Occlusion Who Are Transferred for Endovascular Therapy

Background: The clinical benefit from endovascular therapy (EVT) for patients with acute ischemic stroke is time-dependent. We tested the hypothesis that team prenotification results in faster procedure times prior to initiation of EVT.

Methods: We analyzed data from our prospective database (01/2016–02/2018) including all patients with acute ischemic stroke who were evaluated for EVT at our comprehensive stroke center. We established a standardized algorithm (EVT-Call) in 06/2017 to prenotify team members (interventional neuroradiologist, neurologist, anesthesiologist, CT and angiography technicians) about patient transfer from remote hospitals for evaluation of EVT, and team members were present in the emergency department at the expected patient arrival time. We calculated door-to-image, image-to-groin and door-to-groin times for patients who were transferred to our center for evaluation of EVT, and analyzed changes before (–EVT-Call) and after (+EVT-Call) implementation of the EVT-Call.

Results: Among 494 patients in our database, 328 patients were transferred from remote hospitals for evaluation of EVT (208 -EVT-Call and 120 +EVT-Call, median [IQR] age 75 years [65–81], NIHSS score 17 [12–22], 49.1% female). Of these, 177 patients (54%) underwent EVT after repeated imaging at our center (111/208 [53%) -EVT-Call, 66/120 [55%] +EVT-Call). Median (IQR) door-to-image time (18 min [14–22] vs. 10 min [7–13]; p < 0.001), image-to-groin time (54 min [43.5–69.25] vs. 47 min [38.3–58.75]; p = 0.042) and door-to-groin time (74 min [58–86.5] vs. 60 min [49.3–71]; p < 0.001) were reduced after implementation of the EVT-Call.

Conclusions: Team prenotification results in faster patient assessment and initiation of EVT in patients with acute ischemic stroke. Its impact on functional outcome needs to be determined.

Implementation and Outcomes of an Urban Mobile Adult Extracorporeal Life Support Program

Objective

Methods

Results

Conclusions

Trauma Communications Center Coordinated Severity-Based Stroke Triage: Protocol of a Hybrid Type 1 Effectiveness-Implementation Study

Background: Mechanical thrombectomy (MT) can improve the outcomes of patients with large vessel occlusion (LVO), but a minority of patients with LVO are treated and there are disparities in timely access to MT. In part, this is because in most regions, including Alabama, the emergency medical service (EMS) transports all patients with suspected stroke, regardless of severity, to the nearest stroke center. Consequently, patients with LVO may experience delayed arrival at stroke centers with MT capability and worse outcomes. Alabama's trauma communications center (TCC) coordinates EMS transport of trauma patients by trauma severity and regional hospital capability. Our aims are to develop a severity-based stroke triage (SBST) care model based on Alabama's trauma system, compare the effectiveness of this care pathway to current stroke triage in Alabama for improving broad, equitable, and timely access to MT, and explore stakeholder perceptions of the intervention's feasibility, appropriateness, and acceptability.

Methods: This is a hybrid type 1 effectiveness-implementation study with a multi-phase mixed methods sequential design and an embedded observational stepped wedge cluster trial. We will extend TCC guided stroke severity assessment to all EMS regions in Alabama; conduct stakeholder interviews and focus groups to aid in development of region and hospital specific prehospital and inter-facility stroke triage plans for patients with suspected LVO; implement a phased rollout of TCC Coordinated SBST across Alabama's six EMS regions; and conduct stakeholder surveys and interviews to assess context-specific perceptions of the intervention. The primary outcome is the change in proportion of prehospital stroke system patients with suspected LVO who are treated with MT before and after implementation of TCC Coordinated SBST. Secondary outcomes include change in broad public health impact before and after implementation and stakeholder perceptions of the intervention's feasibility, appropriateness, and acceptability using a mixed methods approach. With 1200 to 1300 total observations over 36 months, we have 80% power to detect a 15% improvement in the primary endpoint.

Discussion: This project, if successful, can demonstrate how the trauma system infrastructure can serve as the basis for a more integrated and effective system of emergency stroke care.