Prehospital Triage Accuracy in Patients With Stroke Symptoms Assessed Within 6 to 24 Hours or With an Unknown Time of Onset

Background and Purpose: The Stockholm Stroke Triage System, implemented in 2017, identifies patients with high likelihood of large vessel occlusion (LVO) stroke. A previous report has shown Stockholm Stroke Triage System notably reduced time to endovascular thrombectomy (EVT). As the indication for EVT now includes patients up to 24 hours, we aimed to assess Stockholm Stroke Triage System triage accuracy for LVO stroke and EVT treatment for patients presenting late (within 6-24 hours or with an unknown onset), put in contrast to triage accuracy within 0 to 6 hours. Methods: Between October 2017 and October 2018, we included 2905 patients with suspected stroke, transported by priority 1 ground ambulance to a Stockholm Region hospital. Patients assessed 6 to 24 hours from last known well or with unknown onset were defined as late-presenting; those within <6 hours as early-presenting. Triage positivity was defined as transport to comprehensive stroke center because of suspected stroke, hemiparesis and high likelihood of EVT-eligible LVO per teleconsultation. Results: Overall triage accuracy was high in late-presenting patients (90.9% for LVO, 93.9% for EVT), with high specificity (95.7% for LVO, 94.5% for EVT), and low to moderate sensitivity (34.3% for LVO, 64.7% for EVT), with similar findings in the early-presenting group. Conclusions: Our results may support using the Stockholm Stroke Triage System for primary stroke center bypass in patients assessed by ambulance up to 24 hours from time of last known well.

Download Full-text

Effect of “drip-and-ship” and “drip-and-drive” on endovascular treatment of acute ischemic stroke with large vessel occlusion: a single-center retrospective study

Acta Radiologica ◽

10.1177/02841851211006897 ◽

2021 ◽

pp. 028418512110068

Author(s):

Yu Hang ◽

Zhen Yu Jia ◽

Lin Bo Zhao ◽

Yue Zhou Cao ◽

Huang Huang ◽

...

Keyword(s):

Ischemic Stroke ◽

Endovascular Treatment ◽

Acute Ischemic Stroke ◽

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Primary Stroke Center ◽

Secondary Endpoints ◽

Comprehensive Stroke Center ◽

Stroke Center

Background Patients with acute ischemic stroke (AIS) caused by large vessel occlusion (LVO) were usually transferred from a primary stroke center (PSC) to a comprehensive stroke center (CSC) for endovascular treatment (drip-and-ship [DS]), while driving the doctor from a CSC to a PSC to perform a procedure is an alternative strategy (drip-and-drive [DD]). Purpose To compare the efficacy and prognosis of the two strategies. Material and Methods From February 2017 to June 2019, 62 patients with LVO received endovascular treatment via the DS and DD models and were retrospectively analyzed from the stroke alliance based on our CSC. Primary endpoint was door-to-reperfusion (DTR) time. Secondary endpoints included puncture-to-recanalization (PTR) time, modified Thrombolysis in Cerebral Infarction (mTICI) rates at the end of the procedure, and modified Rankin Scale (mRS) at 90 days. Results Forty-one patients received the DS strategy and 21 patients received the DD strategy. The DTR time was significantly longer in the DS group compared to the DD group (315.5 ± 83.8 min vs. 248.6 ± 80.0 min; P < 0.05), and PTR time was shorter (77.2 ± 35.9 min vs. 113.7 ± 69.7 min; P = 0.033) compared with the DD group. Successful recanalization (mTICI 2b/3) was achieved in 89% (36/41) of patients in the DS group and 86% (18/21) in the DD group ( P = 1.000). Favorable functional outcomes (mRS 0–2) were observed in 49% (20/41) of patients in the DS group and 71% (15/21) in the DD group at 90 days ( P = 0.089). Conclusion Compared with the DS strategy, the DD strategy showed more effective and a trend of better clinical outcomes for AIS patients with LVO.

Download Full-text

Prehospital Comprehensive Stroke Center vs Primary Stroke Center Triage in Patients With Suspected Large Vessel Occlusion Stroke

JAMA Neurology ◽

10.1001/jamaneurol.2021.2485 ◽

2021 ◽

Author(s):

Tareq Kass-Hout ◽

Jungwha Lee ◽

Katie Tataris ◽

Christopher T. Richards ◽

Eddie Markul ◽

...

Keyword(s):

Large Vessel ◽

Large Vessel Occlusion ◽

Vessel Occlusion ◽

Primary Stroke Center ◽

Comprehensive Stroke Center ◽

Stroke Center

Download Full-text

Prehospital Stroke Triage

Neurology ◽

10.1212/wnl.0000000000012792 ◽

2021 ◽

Vol 97 (20 Supplement 2) ◽

pp. S25-S33

Author(s):

Anna Ramos ◽

Waldo R. Guerrero ◽

Natalia Pérez de la Ossa

Keyword(s):

Acute Stroke ◽

Randomized Clinical Trials ◽

Vessel Occlusion ◽

Novel Technologies ◽

Maximum Benefit ◽

Prehospital Management ◽

Prehospital Triage ◽

Clinical Tools ◽

Comprehensive Stroke Center ◽

Stroke Center

Purpose of the ReviewThis article reviews prehospital organization in the treatment of acute stroke. Rapid access to an endovascular therapy (EVT) capable center and prehospital assessment of large vessel occlusion (LVO) are 2 important challenges in acute stroke therapy. This article emphasizes the use of transfer protocols to assure the prompt access of patients with an LVO to a comprehensive stroke center where EVT can be offered. Available prehospital clinical tools and novel technologies to identify LVO are also discussed. Moreover, different routing paradigms like first attention at a local stroke center (“drip and ship”), direct transfer of the patient to an endovascular center (“mothership”), transfer of the neurointerventional team to a local primary center (“drip and drive”), mobile stroke units, and prehospital management communication tools all aimed to improve connection and coordination between care levels are reviewed.Recent FindingsLocal observational data and mathematical models suggest that implementing triage tools and bypass protocols may be an efficient solution. Ongoing randomized clinical trials comparing drip and ship vs mothership will elucidate which is the more effective routing protocol.SummaryPrehospital organization is critical in realizing maximum benefit from available therapies in acute stroke. The optimal transfer protocols directed to accelerate EVT are under study, and more accurate prehospital triage tools are needed. To improve care in the prehospital setting, efficient tools based on patient factors, local geography, and hospital capability are needed. These tools would optimally lead to individualized real-time decision-making.

Download Full-text

Abstract MP35: Blood Pressure Reductions Before Arrival at a Thrombectomy-Capable Hospital Are Associated With Neurologic Worsening in Patients With Large-Vessel Occlusion

Stroke ◽

10.1161/str.52.suppl_1.mp35 ◽

2021 ◽

Vol 52 (Suppl_1) ◽

Author(s):

Jessica Kobsa ◽

Ayush Prasad ◽

Alexandria Soto ◽

Sreeja Kodali ◽

Cindy Khanh Nguyen ◽

...

Keyword(s):

Blood Pressure ◽

Management Strategies ◽

Vessel Occlusion ◽

Time Points ◽

Good Outcome ◽

Primary Stroke Center ◽

Poor Outcomes ◽

Comprehensive Stroke Center ◽

Stroke Center ◽

Radiographic Data

Introduction: Decreases in blood pressure (BP) during thrombectomy are associated with infarct progression and worse outcomes. Many patients present first to a primary stroke center (PSC) and are later transferred to a comprehensive stroke center (CSC) to undergo thrombectomy. During this period, important BP variations might occur. We evaluated the association of BP reductions with neurological worsening and functional outcomes. Methods: We prospectively collected hemodynamic, clinical, and radiographic data on consecutive patients with LVO ischemic stroke who were transferred from a PSC for possible thrombectomy between 2018 and 2020. We assessed systolic BP (SBP) and mean arterial pressure (MAP) at five time points: earliest recorded, average pre-PSC, PSC admission, average PSC, and CSC admission. We measured neurologic worsening as a change in NIHSS (ΔNIHSS) from PSC to CSC >3 and functional outcome using the modified Rankin Scale (mRS) at discharge and 90 days. Relationships between variables of interest were evaluated using linear regression. Results: Of 91 patients (mean age 70±16 years, mean NIHSS 12) included, 13 (14%) experienced early neurologic deterioration (ΔNIHSS>3), and 34 (37%) achieved a good outcome at discharge (mRS<3). We found that patients with good outcome had significantly lower SBP at all five assessed time points compared to patients with poor outcome (Figure 1, p<0.05). Percent change in MAP from initial presentation to CSC arrival was independently associated with ΔNIHSS after adjusting for age, sex, and transfer time (p=0.03, β=0.27). Conclusions: Patients with poor outcomes have higher BP throughout the pre-CSC period, possibly reflecting an augmented hypertensive response. Reductions in SBP and MAP before arrival at the CSC are associated with neurologic worsening. These results suggest that BP management strategies in the pre-CSC period to avoid large reductions in BP may improve outcomes in patients affected by LVO stroke.

Download Full-text

Abstract WP340: Impact of Increasing Primary Stroke Center Transfers on Comprehensive Stroke Center Capacity

Stroke ◽

10.1161/str.51.suppl_1.wp340 ◽

2020 ◽

Vol 51 (Suppl_1) ◽

Author(s):

Jane Holl ◽

Andy Cai ◽

Lauren Ha ◽

Alin Hulli ◽

Melina Paan ◽

...

Keyword(s):

Systems Of Care ◽

Vessel Occlusion ◽

Capacity Limits ◽

Transfer Rates ◽

Primary Stroke Center ◽

Comprehensive Stroke Center ◽

Stroke Systems Of Care ◽

Stroke Center ◽

Occupancy Rates ◽

Bed Occupancy Rates

Introduction: Given the time-sensitive benefits of acute stroke (AS) treatments, stroke systems of care must balance reducing door-in-door-out (DIDO) time at primary stroke centers (PSCs) with capacity limits at comprehensive stroke centers (CSCs). For example transferring more AS patients earlier in the process (e.g., prior vascular imaging for large vessel occlusion) from PSCs would result in more inappropriate transfers to CSCs that could overburden these centers.We conducted a simulation to estimate the balance between increased AS transfers from PSCs to CSCs and the percent of CSC time on “bypass” (inability to accept transfers to neuro-ICU). Methods: Clinicians from 3 Chicago-area CSCs and 3 affiliated PSCs and the Chicago Emergency Medical Services (EMS) created a PSC DIDO process map. We assumed CSC time on bypass is affected by AS and non-AS admissions from the CSC and from the affiliated PSCs. Input data were obtained fromtheChicago region registry (e.g., # PSC to CSC transfers), peer reviewed literature (US average transfer rate of AS patients to CSCs), EMS (PSC-CSC affiliations), and CSCs (e.g., average bed occupancy rates). CSC size was estimated by #neuro-ICU beds: small (12 beds), medium (23 beds), and large (28 beds). The simulation output was % time of CSC on “bypass”. Results: Table shows % time of CSC on bypass by varying PSC AS transfer rates for each category of CSC size. Larger increases in PSC transfer rates resulted in modest increases in CSC bypass rates, particularly for medium and large CSCs. Validation with data from one CSC showed < 4% overestimate of CSC % time on bypass. Conclusion: CSCs with more beds have efficiencies of scale leading to lower % time on bypass, even with increases in PSC AS transfer rates proportionate to CSC size. This model allows stroke systems of care to compute regional CSCs’ % time on bypass based on actual PSCs’ transfer rates and CSC size.

Download Full-text

Personalized Prehospital Triage in Acute Ischemic Stroke

Stroke ◽

10.1161/strokeaha.118.022562 ◽

2019 ◽

Vol 50 (2) ◽

pp. 313-320 ◽

Cited By ~ 7

Author(s):

Esmee Venema ◽

Hester F. Lingsma ◽

Vicky Chalos ◽

Maxim J.H.L. Mulder ◽

Maarten M.H. Lahr ◽

...

Keyword(s):

Ischemic Stroke ◽

Large Vessel ◽

Base Case ◽

Large Vessel Occlusion ◽

Case Scenario ◽

Vessel Occlusion ◽

Base Case Scenario ◽

Primary Stroke Center ◽

Prehospital Triage ◽

Stroke Center

Background and Purpose— Direct transportation to a center with facilities for endovascular treatment might be beneficial for patients with acute ischemic stroke, but it can also cause harm by delay of intravenous treatment. Our aim was to determine the optimal prehospital transportation strategy for individual patients and to assess which factors influence this decision. Methods— We constructed a decision tree model to compare outcome of ischemic stroke patients after transportation to a primary stroke center versus a more distant intervention center. The optimal strategy was estimated based on individual patient characteristics, geographic location, and workflow times. In the base case scenario, the primary stroke center was located at 20 minutes and the intervention center at 45 minutes. Additional sensitivity analyses included an urban scenario (10 versus 20 minutes) and a rural scenario (30 versus 90 minutes). Results— Direct transportation to the intervention center led to better outcomes in the base case scenario when the likelihood of a large vessel occlusion as a cause of the ischemic stroke was >33%. With a high likelihood of large vessel occlusion (66%, comparable with a Rapid Arterial Occlusion Evaluation score of 5 or above), the benefit of direct transportation to the intervention center was 0.10 quality-adjusted life years (=36 days in full health). In the urban scenario, direct transportation to an intervention center was beneficial when the risk of large vessel occlusion was 24% or higher. In the rural scenario, this threshold was 49%. Other factors influencing the decision included door-to-needle times, door-to-groin times, and the door-in-door-out time. Conclusions— The preferred prehospital transportation strategy for suspected stroke patients depends mainly on the likelihood of large vessel occlusion, driving times, and in-hospital workflow times. We constructed a robust model that combines these characteristics and can be used to personalize prehospital triage, especially in more remote areas.

Download Full-text

The “Flying Intervention Team”: A Novel Stroke Care Concept for Rural Areas

Cerebrovascular Diseases ◽

10.1159/000514845 ◽

2021 ◽

pp. 1-8

Author(s):

Gordian Jan Hubert ◽

Frank Kraus ◽

Christian Maegerlein ◽

Sabine Platen ◽

Benjamin Friedrich ◽

...

Keyword(s):

Endovascular Treatment ◽

Rural Areas ◽

Stroke Care ◽

Vessel Occlusion ◽

Angiography Suite ◽

Secondary Transfer ◽

Primary Stroke Center ◽

Intervention Team ◽

Comprehensive Stroke Center ◽

Stroke Center

Background: Endovascular treatment of large vessel occlusion in acute ischemic stroke patients is difficult to establish in remote areas, and time dependency of treatment effect increases the urge to develop health care concepts for this population. Summary: Current strategies include direct transportation of patients to a comprehensive stroke center (CSC) (“mothership model”) or transportation to the nearest primary stroke center (PSC) and secondary transfer to the CSC (“drip-and-ship model”). Both have disadvantages. We propose the model “flying intervention team.” Patients will be transported to the nearest PSC; if telemedically identified as eligible for thrombectomy, an intervention team will be acutely transported via helicopter to the PSC and endovascular treatment will be performed on site. Patients stay at the PSC for further stroke unit care. This model was implemented at a telestroke network in Germany. Fifteen remote hospitals participated in the project, covering 14,000 km2 and a population of 2 million. All have well established telemedically supported stroke units, an angiography suite, and a helicopter pad. Processes were defined individually for each hospital and training sessions were implemented for all stroke teams. An exclusive project helicopter was installed to be available from 8 a.m. to 10 p.m. during 26 weeks per year. Key Messages: The model of the flying intervention team is likely to reduce time delays since processes will be performed in parallel, rather than consecutively, and since it is quicker to move a medical team rather than a patient. This project is currently under evaluation (clinicaltrials NCT04270513).

Download Full-text

Abstract 1122‐000137: Characteristics and Utilization of Acute Reperfusion Therapy after Transfer of In‐Hospital LVO Strokes

Stroke: Vascular and Interventional Neurology ◽

10.1161/svin.01.suppl_1.000137 ◽

2021 ◽

Vol 1 (S1) ◽

Author(s):

Rahul Rao ◽

Conor Kelly ◽

Shashvat Desai ◽

Ashutosh Jadhav

Keyword(s):

Tertiary Care ◽

Reperfusion Therapy ◽

Artery Occlusion ◽

Basilar Artery Occlusion ◽

Stroke Patients ◽

Vessel Occlusion ◽

Primary Stroke Center ◽

Comprehensive Stroke Center ◽

Stroke Center ◽

Iv Tpa

Introduction : Acute repercussion therapy for acute ischemic stroke is a crucial tool in the tertiary care setting for patients presenting with large vessel occlusion (LVO). While strokes that present from the community have favorable outcomes compared to in‐hospital strokes, it is unclear if this is because of greater access to endovascular therapy. We aim to characterize the utilization of endovascular reperfusion therapy for in‐house LVO and compare outcomes of in‐house LVOs to those presenting from the community. Methods : From the period of December 2013 to December 2019, all stroke patients with an LVO who presented to a primary stroke center (“spoke” hospital) who were transferred to a comprehensive stroke center (“hub”) were analyzed. Univariate and multivariate analyses were performed to compare baseline characteristics and clinical outcomes. Results : A total of 181 in‐house strokes were transferred from a peripheral center to our comprehensive stroke center. About 16% (29) received IV‐tPA at the OSH and 2 additional patients received IV‐tPA at the CSC [17%; n = 31]. 163 patients harbored an intracranial acute vessel occlusion. Anterior LVO (ICA, M1,M2) and basilar artery occlusion was observed in 64% (n = 116) patients and 6% (n = 11) patients, respectively [Total LVO‐ 70%; n = 127]. 20% (n = 27) of LVO received IV‐tPA and 72% (n = 91) of LVO underwent thrombectomy. Reasons for not receiving included symptoms improved (25%), repeat imaging made reperfusion inadvisable (72.2%) and poor baseline (2.8%). Rates of mRS 0–2 in patients with ICA/M1/M2 receiving EVT were 13% (13/100) and the mortality rate was 45% (46/103). Rates of mRS 0–2 were significantly lower [13% vs 38%, p<0.01] and mortality was significantly higher [45% vs 18%, p<0.01] amongst anterior LVO in‐house transfer patients receiving EVT compared to all anterior LVO patients receiving EVT in the given time period. Conclusions : A relatively large proportion of in‐house LVO stroke patients underwent thrombectomy (70%). Most common cause of not receiving thrombectomy was imaging findings showing completed or large infarct. Compared to their community stroke counterparts, in‐house LVO strokes had lower efficacy outcomes and higher mortality. Further study in required to understand these findings.

Download Full-text

Pre- and Interhospital Workflow Times for Patients With Large Vessel Occlusion Stroke Transferred for Endovasvular Thrombectomy

Frontiers in Neurology ◽

10.3389/fneur.2021.730250 ◽

2021 ◽

Vol 12 ◽

Author(s):

Laura C. C. van Meenen ◽

Frank Riedijk ◽

Jeffrey Stolp ◽

Bas van der Veen ◽

Patricia H. A. Halkes ◽

...

Keyword(s):

Intravenous Thrombolysis ◽

Large Vessel ◽

Time Interval ◽

Large Vessel Occlusion ◽

Related Factors ◽

Vessel Occlusion ◽

Interhospital Transfer ◽

Primary Stroke Center ◽

Comprehensive Stroke Center ◽

Stroke Center

Background: Patients with large vessel occlusion (LVO) stroke are often initially admitted to a primary stroke center (PSC) and subsequently transferred to a comprehensive stroke center (CSC) for endovascular thrombectomy (EVT). This interhospital transfer delays initiation of EVT. To identify potential workflow improvements, we analyzed pre- and interhospital time metrics for patients with LVO stroke who were transferred from a PSC for EVT.Methods: We used data from the regional emergency medical services and our EVT registry. We included patients with LVO stroke who were transferred from three nearby PSCs for EVT (2014–2021). The time interval between first alarm and arrival at the CSC (call-to-CSC time) and other time metrics were calculated. We analyzed associations between various clinical and workflow-related factors and call-to-CSC time, using multivariable linear regression.Results: We included 198 patients with LVO stroke. Mean age was 70 years (±14.9), median baseline NIHSS was 14 (IQR: 9–18), 136/198 (69%) were treated with intravenous thrombolysis, and 135/198 (68%) underwent EVT. Median call-to-CSC time was 162 min (IQR: 137–190). In 133/155 (86%) cases, the ambulance for transfer to the CSC was dispatched with the highest level of urgency. This was associated with shorter call-to-CSC time (adjusted β [95% CI]: −27.6 min [−51.2 to −3.9]). No clinical characteristics were associated with call-to-CSC time.Conclusion: In patients transferred from a PSC for EVT, median call-to-CSC time was over 2.5 h. The highest level of urgency for dispatch of ambulances for EVT transfers should be used, as this clearly decreases time to treatment.

Download Full-text

Ambulance waiting and associated work flow improvement strategies: a pilot study to improve door-in-door-out time for thrombectomy patients in a primary stroke center

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2021-017653 ◽

2021 ◽

pp. neurintsurg-2021-017653

Author(s):

Eva Gaynor ◽

Emma Griffin ◽

John Thornton ◽

Jack Alderson ◽

Mary Martin ◽

...

Keyword(s):

Emergency Service ◽

Service Usage ◽

Vessel Occlusion ◽

Time Period ◽

Significant Difference ◽

Primary Stroke Center ◽

Historical Group ◽

Comprehensive Stroke Center ◽

Stroke Center ◽

Flow Improvement

BackgroundRapid access to thrombectomy for patients with large vessel occlusion (LVO) acute ischemic stroke (AIS) is critical for improving outcome. A major challenge for the ‘drip and ship’ model is reducing the door-in-door-out time (DIDO). We propose a new protocol with the aim of reducing DIDO, without adversely affecting emergency service usage time.MethodsConsecutive patients with suspected LVO AIS admitted to a Primary Stroke Center (PSC) from October 2018 to January 2021 were included. On arrival, the ambulance crew remained with the patient. Following immediate clinical and radiological evaluation, patients were transferred to the Comprehensive Stroke Center (CSC) by the same waiting crew. Key time metrics were collected and compared with historical data prior to the new protocol.Results27 patients had an LVO amenable for mechanical thrombectomy during the time period. There was a significant reduction in the DIDO times compared with the historical group (median 45 min vs 96 min; p<0.0001). There was no significant difference in ambulance usage time between the two time periods (median 53 min vs 45 min; p=0.530). There was an increase in ambulance usage time in FAST-positive patients not for transfer in the pilot group compared with FAST-positive patients not for transfer in the historical group (27 min vs 58 min; p<0.001). In addition, door-to-needle times (24 min vs 40 min; p=0.018) and door-to-CT times (11 min vs 25 min; p<0.0001) improved between the two groups.ConclusionOur data show a significant reduction in the DIDO for patients transferred for thrombectomy, with no adverse effects on ambulance usage time.

Download Full-text