Strategies to reduce delays in delivering mechanical thrombectomy for acute ischaemic stroke - an umbrella review

Background

Mechanical thrombectomy is a time-sensitive treatment, with rapid initiation and reduced delays being associated with better patient outcomes. Several systematic reviews reported on various interventions to address delays. Hence, we performed an umbrella review of systematic reviews to summarise the current evidence.

Methods

Medline, Embase, Cochrane Library and JBI were searched for published systematic reviews. Systematic Reviews that detailed outcomes related to time-to-thrombectomy or functional independence were included. Methodological quality was assessed using the JBI critical appraisal tool by two independent reviewers.

Results

A total of 17 systematic reviews were included in the review. These were all assessed as high-quality reviews. A total of 13 reviews reported on functional outcomes, and 12 reviews reported on time-to-thrombectomy outcomes. Various interventions were identified as beneficial. The most frequently reported beneficial interventions that improved functional and time-related outcomes included: direct-to-angio-suite and using a mothership model (compared to drip-and-ship). Only a few studies investigated other strategies including other pre-hospital and teamwork strategies.

Conclusion

Overall, there were various strategies that can be used to reduce delays in the delivery of mechanical thrombectomy with different effectiveness. The mothership model appears to be superior to the drip-and-ship model in reducing delays and improving functional outcomes. Additionally, the direct-to-angiosuite approach appears to be beneficial, but further research is required for broader implementation of this approach and to determine which groups of patients would benefit the most.

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.

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).

Prehospital triage optimization of patients with large vessel occlusion by Austrian Prehospital Stroke Scale

OBJECTIVES

The Austrian Prehospital Stroke Scale (APSS) score was developed to predict large vessel occlusion (LVO) and improve prehospital transportation triage. Its accuracy has been previously analyzed retrospectively. We now aimed to investigate the accuracy, as well as the impact of the implementation of a triage strategy using this score on treatment times and outcome in a prospective study.

MATHERIAL & METHODS

Prospective diagnostic test accuracy and before-after interventional study. EMS prospectively evaluated APSS in patients suspected of stroke. Accuracy was compared with other LVO scores. Patients with APSS ≥4 points were brought directly to the comprehensive stroke center. Treatment time frames, neurological, and radiological outcome before and after the APSS implementation were compared.

RESULTS

A total of 307 patients with suspected stroke were included from October 2018 to February 2020. Treatable LVO was present in 79 (26%). Sensitivity of APSS to detect those was 90%, specificity 79%, positive predictive value 66%, negative predictive value 95%, and area under the curve 0.87 (95% CI 0.83-0.91). This was similar to in-hospital NIHSS (AUC 0.89 95% CI 0.89-0.92, p = .06) and superior to CPSS (AUC 0.83 95% CI 0.78-0.87, p = .01). Implementation of APSS triage increased direct transportation rate for LVO patients (21% before vs. 52% after; p < .001) with a significant time benefit (alert to groin puncture time benefit: 51 min (95% CI 28-74; p < .001). Neurological and radiological outcome did not differ significantly.

CONCLUSIONS

Austrian Prehospital Stroke Scale triage showed an accuracy comparable with in-hospital NIHSS, and lead to a significant optimization of prehospital workflows in patients with potential LVO.

Modeling the Impact of Prehospital Triage on a True-Life Drip and Ship Mechanical Thrombectomy Urban Patient Cohort

Objective

The aim of the study was to model the effect of prehospital triage of emergent large vessel occlusion (ELVO) to endovascular capable center (ECC) on the timing of thrombectomy and intravenous (IV) thrombolysis using real-world data from a multihospital system.

Methods

We selected a cohort of 77 consecutive stroke patients who were brought by emergency medical services (EMS) to a nonendovascular capable center and then transferred to an ECC for mechanical thrombectomy (MT) (“actual” drip and ship [DS] cohort). We created a hypothetical scenario (bypass model [BM]), modeling transfer of the patients directly to an ECC, based on patients' initial EMS pickup address and closest ECC. Using another cohort of 73 consecutive patients, who were brought directly to an ECC by EMS and underwent endovascular intervention, we calculated mean door-to-needle and door-to-arterial puncture (AP) times (“actual” mothership [MS] cohort). Timings in the actual MS cohort and the actual DS cohort were compared to timings from the BM cohort.

Results

Median first medical contact (FMC) to IV thrombolysis time was 87.5 min (interquartile range [IQR] = 38) for the DS versus 78.5 min (IQR = 8.96) for the BM cohort, with p = 0.1672. Median FMC to AP was 244 min (IQR = 97) versus 147 min (IQR = 8.96) (p < 0.001), and median FMC to TICI 2B+ time was 299 min (IQR = 108.5) versus 197 min (IQR = 8.96) (p < 0.001) for the DS versus BM cohort, respectively.

Conclusions

Modeled EMS prehospital triage of ELVO patients' results in shorter MT times without a change in thrombolysis times. As triage tools increase in sensitivity and specificity, EMS triage protocols stand to improve patient outcomes.

Transcranial Doppler Ultrasonography in Pre-hospital Management of Stroke: Can it make a Difference?

The aim of this paper is to discuss the use of transcranial doppler in the pre-hospital management of stroke. In the pre-hospital organization, neurological defect scales are used, but they are often indicative of the occlusions of anterior circulation and not of the posterior circulation. Patients with posterior circulation stroke are sometimes not diagnosed and clinically treated. In the pre-hospital phase, the transcranial doppler may identify an occlusion of the large cerebral vessels and be useful for stroke patients, in particular those with posterior occlusions, for a more precise diagnosis and consequently for adequate treatment in the excellence centers for stroke.

Efficacy and safety of bridging thrombolysis initiated before transfer in a drip-and-ship stroke service

Objective

Data regarding the efficacy and safety of bridging thrombolysis (BT) initiated before transfer for evaluation of endovascular therapy is heterogeneous. We, therefore, analyse efficacy and safety of BT in patients treated within a drip-and-ship stroke service.

Methods

Consecutive adult patients suffering from acute ischaemic stroke and large-vessel occlusions (LVO) transferred to our comprehensive stroke centre for evaluation of endovascular therapy in 2017–2020 were identified from a local prospective stroke database and categorised according to BT and no-BT. BT was defined as intravenous thrombolysis initiated before transfer. LVO was assessed before and after transfer. Functional outcome before stroke and at 3 months using the modified Rankin scale (mRS) was determined. Excellent outcome was defined as mRS 0–1 or return to prestroke mRS. For safety analysis, intracranial haemorrhages and mortality at 3 months were analysed. Main analysis was limited to patients with anterior circulation stroke.

Results

Of N=714 patients, n=394 (55.2%) received BT. More patients in the BT group with documented LVO before transfer recanalised without endovascular therapy (n=46, 11.7%) than patients who did not receive BT before transfer (n=4, 1.3%, p<0.001). In multivariate analysis, BT was the strongest independent predictor of early recanalisation (adjusted OR 10.9, 95% CI 3.8 to 31.1, p<0.001). BT tended to be an independent predictor of an excellent outcome at 3 months (adjusted OR 1.38, 95% CI 0.97 to 1.96, p=0.077). There were no differences in safety between the BT and no-BT groups.

Conclusions

BT initiated before transfer was a strong independent predictor of early recanalisation.

Communication in interprofessional rehabilitation teams: a scoping review

PURPOSE

Effective communication in interprofessional rehabilitation teams is essential for optimal patient care. Despite the established importance, it remains unclear how interprofessional communication (IPC) within teams contributes to rehabilitation service delivery. The aim of this scoping review was to investigate how IPC has been described in rehabilitation literature.

METHODS

Databases (Medline, CINAHL, ERIC, Embase, PsychInfo, and Academic Search Complete) were searched for studies including rehabilitation interprofessional communication. Inclusion and exclusion criteria were identified and applied, data were charted, and thematic analysis conducted.

RESULTS

Twenty-nine papers were identified, and analysis revealed interrelated themes: communication processes, and inputs and effects. Formal communication processes were most prevalent, portraying variability in professional participation and a lack of patient involvement in dialogue and decision making. Inputs and effects were described at an organisational, team and individual level, highlighting the importance of communication throughout the healthcare hierarchy.

CONCLUSIONS

IPC in rehabilitation is central to effective team function and patient care. To further our understanding, empirical studies examining everyday informal IPC, as well as formal ritualised encounters are needed. Additionally, conceptualisations of IPC would benefit from including the patients' perspective and by using theoretical framing to attend to places, spaces, and artefacts identified in this review.

Pathway Design for Acute Stroke Care in the Era of Endovascular Thrombectomy: A Critical Overview of Optimization Efforts

The efficacy of intravenous thrombolysis and endovascular thrombectomy (EVT) for acute ischemic stroke is highly time dependent. Optimal organization of acute stroke care is therefore important to reduce treatment delays but has become more complex after the introduction of EVT as regular treatment for large vessel occlusions. There is no singular optimal organizational model that can be generalized to different geographic regions worldwide. Current dominant organizational models for EVT include the drip-and-ship- and mothership model. Guidelines recommend routing of suspected patients with stroke to the nearest intravenous thrombolysis capable facility; however, the choice of routing to a certain model should depend on regional stroke service organization and individual patient characteristics. In general, design approaches for organizing stroke care are required, in which 2 key strategies could be considered. The first entails the identification of interventions within existing organizational models for optimizing timely delivery of intravenous thrombolysis and/or EVT. This includes adaptive patient routing toward a comprehensive stroke center, which focuses particularly on prehospital triage tools; bringing intravenous thrombolysis or EVT to the location of the patient; and expediting services and processes along the stroke pathway. The second strategy is to develop analytical or simulation model-based approaches enabling the design and evaluation of organizational models before their implementation. Organizational models for acute stroke care need to take regional and patient characteristics into account and can most efficiently be assessed and optimized through the application of model-based approaches.

The association between computed tomography angiography timing and workflow times in patients with acute ischemic stroke

BACKGROUND

In most hospitals, computed tomography angiography (CTA) is nowadays routinely performed in patients with acute ischemic stroke. However, it is unclear whether CTA is best performed before or after start of intravenous thrombolysis (IVT), since acquisition of CTA before IVT may prolong door-to-needle times, while acquisition after IVT may prolong door-to-groin times in patients undergoing endovascular treatment.

METHODS

We performed a before-versus-after study (CTA following IVT, period I and CTA prior to IVT, period II), consisting of two periods of one year each. This study is based on a prospective registry of consecutive patients treated with IVT in two collaborating high-volume stroke centers; one primary stroke center and one comprehensive stroke center. The primary outcome was door-to-needle times. Secondary outcomes included door-to-groin times. Quantile regression analyses were performed to evaluate the association between timing of CTA and workflow times, adjusted for prognostic factors.

RESULTS

A total of 519 patients received IVT during the study period (246 in period I, 273 in period II). In the adjusted analysis, we found a nonsignificant 1.13 min median difference in door-to-needle times (95% confidence interval: 1.03-3.29). Door-to-groin times was significantly shorter in period II in both unadjusted and adjusted analysis with the latter showing a 19.16 min median difference (95% confidence interval: 3.08-35.24).

CONCLUSIONS

CTA acquisition prior to start of IVT did not adversely affect door-to-needle times. However, a significantly shorter door-to-groin times was observed in endovascular treatment eligible patients. Performing CTA prior to start of IVT seems the preferred strategy.

Mothership versus Drip-and-Ship Model for Mechanical Thrombectomy in Acute Stroke: A Systematic Review and Meta-Analysis for Clinical and Radiological Outcomes

Background and Purpose

Substantial uncertainty exists on the benefit of organizational paradigms in stroke networks. Here we systematically reviewed and meta-analyzed data from studies comparing functional outcome between the mothership (MS) and the drip and ship (DS) models.

Methods

The meta-analysis protocol was registered international prospective register of systematic reviews (PROSPERO) and followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, EMBASE, and Cochrane Central databases were searched for randomized-controlled clinical trials (RCTs), retrospective and prospective studies comparing MS versus DS. Primary endpoints were functional independence at 90 days (modified Rankin Scale <3) and successful recanalization (Thrombolysis in Cerebral Infarction Scale [TICI] >2a); secondary endpoints were 3-month mortality and symptomatic intracranial haemorrhage (sICH). Odds ratios for endpoints were pooled using the random effects model and were compared between the two organizational models.

Results

Overall, 18 studies (n=7,017) were included in quantitative synthesis. MS paradigm was superior to DS model for functional independence (odds ratio, 1.34; 95% confidence interval, 1.16 to 1.55; I²=30%). Meta-regression analysis revealed association between onset-to-needle time and good functional outcome, with longer onset-to-needle time being detrimental. Similar rates of recanalization, sICH and mortality at 90 days were documented between MS and DS.

Conclusions

Patients with acute ischemic stroke eligible for reperfusion strategies might benefit more from MS paradigm as compared to DS. RCTs are needed to further refine best management taking into account logistics, facilities and resources.

Emerging therapies in acute ischemic stroke

Thrombolysis and mechanical thrombectomy have revolutionized the care of patients with acute ischemic stroke. The number of patients who can benefit from these treatments continues to increase as new studies demonstrate that not just time since stroke onset but also collateral circulation influences outcome. Technologies such as telestroke, mobile stroke units, and artificial intelligence are playing an increasing role in identifying and treating stroke. Stroke-systems-of-care models continue to streamline the delivery of definitive revascularization in the age of mechanical thrombectomy.

Impact of EMS bypass to endovascular capable hospitals: geospatial modeling analysis of the US STRATIS registry

BACKGROUND

Routing patients directly to endovascular capable centers (ECCs) would decrease time to mechanical thrombectomy (MT), but may delay intravenous thrombolysis (IVT).

OBJECTIVE

To study the clinical outcomes of patients with a stroke transferred directly to ECCs compared with those transferred to ECCs from non-endovascular capable centers (nECCs).

METHODS

Data from the STRATIS registry were analyzed to evaluate process and clinical outcomes under five routing policies: (1) transport to nearest nECC; (2) transport to STRATIS ECC over any distance or (3) within 20 miles; (4) transport to ideal ECC (iECC), over any distance or (5) within 20 miles.

RESULTS

Among 236 patients, 117 (49.6%) were transferred by ground, of whom 62 (53%) were transferred within 20 miles. Median MT start time was accelerated in all direct transport models. IVT start was prolonged with direct transport across all distances, but accelerated with direct transport to iECC ≤20 miles. With bypass limited to ≤20 miles, the median modeled EMS arrival to IVT interval decreased for both iECCs and ECCs (by 12 min and 6 min, respectively), and median EMS arrival to puncture time decreased by up to 94 min. In this cohort, no patient would have become ineligible for IVT. Bypass to iECC modeling under 20 miles showed a significant reduction in the level of disability at 3 months, with freedom from disability (modified Rankin Scale score 0-1) at 3 months increased by 12%.

CONCLUSIONS

Direct routing of patients with a large vessel occlusion to ECCs, especially when within 20 miles, may lead to better clinical outcomes by accelerating the start of MT without any delay of IVT.

CLINICAL TRIAL REGISTRATION NUMBER

http://www.clinicaltrials.gov. Unique identifier: NCT02239640.

Safety of inter-hospital transfer of patients with acute ischemic stroke for evaluation of endovascular thrombectomy

Stroke networks facilitate access to endovascular treatment (EVT) for patients with ischemic stroke due to large vessel occlusion. In this study we aimed to determine the safety of inter-hospital transfer and included all patients with acute ischemic stroke who were transferred within our stroke network for evaluation of EVT between 06/2016 and 12/2018. Data were derived from our prospective EVT database and transfer protocols. We analyzed major complications and medical interventions associated with inter-hospital transfer. Among 615 transferred patients, 377 patients (61.3%) were transferred within our telestroke network and had transfer protocols available (median age 76 years [interquartile range, IQR 17], 190 [50.4%] male, median baseline NIHSS score 17 [IQR 8], 246 [65.3%] drip-and-ship i.v.-thrombolysis). No patient suffered from cardio-respiratory failure or required emergency intubation or cardiopulmonary resuscitation during the transfer. Among 343 patients who were not intubated prior departure, 35 patients (10.2%) required medical interventions during the transfer. The performance of medical interventions was associated with a lower EVT rate and higher mortality at three months. In conclusion, the transfer of acute stroke patients for evaluation of EVT was not associated with major complications and transfer-related medical interventions were required in a minority of patients.

Drip and ship for mechanical thrombectomy within the Neurovascular Network of Southwest Bavaria

Objective

To determine feasibility and safety of stroke care organization within our Neurovascular Network of Southwest Bavaria (NEVAS) in a rural area with distances of up to 100 kilometers, we compared patients who underwent mechanical thrombectomy (MT) in large vessel occlusion admitted directly to our center (direct to center [DTC]) to patients who were transferred for MT via NEVAS (drip and ship [DS]).

Methods

This is a retrospective analysis of prospectively collected data of all MT patients between January 2015 and May 2018. Successful recanalization was defined as a thrombolysis in cerebral infarction score of 2b-3. Symptomatic intracerebral hemorrhage (sICH) was defined according to European Cooperative Acute Stroke Study 3. Modified Rankin Scale (mRS) score of 0–2 at 3 months indicated good outcome.

Results

MT was performed in 410 patients: 221 DTC and 189 DS. Median NIH Stroke Scale (NIHSS) score was 16 and premorbid mRS score was 0. Thrombolysis was applied in 62.2% with the same time from symptom onset in both groups (94.5 vs 95 minutes). Successful recanalization (79.3% vs 77.8%) and NIHSS score reduction from admission to discharge (16–7 vs 17–6) were comparable. Time delay from onset to revascularization was 96 minutes in DS (212 vs 308 minutes, p = 0.001). At follow-up, DTC patients had a trend to better outcome (33.5% vs 24.3%, p = 0.056). Neither sICH (6.3% vs 5.9%, p = 0.840) nor mortality (31.2% vs 34.4%, p = 0.387) differed between the groups.

Conclusion

DS patients benefit from MT without relevant safety concerns, but with a trend to unfavorable outcome compared to DTC patients. These results suggest that DS is suitable to provide MT in rural areas where DTC is not possible.

[Mothership or drip and ship?]

BACKGROUND

The scientific evidence of the high efficacy of endovascular stroke treatment in large vessel occlusion (LVO) led to this treatment being accepted as the gold standard in these patients.

OBJECTIVE

This review article presents the various organizational models for thrombectomy and analyzes which model is preferred under which circumstances.

MATERIAL AND METHODS

In an analysis of the recent scientific literature the models for optimizing patient transport (drip and ship or mothership) and optimizing the availability of interventionalists (drip and drive or remote mentoring) are presented and compared. In addition, considerations are made on thrombectomy rates and the prevalence of LVOs and the construction of organizational models.

RESULTS

If the location of the stroke patient is just as far from or closer to a comprehensive stroke center (CSC) than a primary stroke center (PSC), the patient should be transported directly to the CSC by mothership. If, on the other hand, a PSC is closer to the stroke site than a CSC and the time after the onset of symptoms lies within the lysis time window, this decision depends on many variables.

CONCLUSION

Based on the unambiguous data situation, no recommendations can currently be made for a generally superior organizational model.

Cutting Edge Acute Ischemic Stroke Management

Acute ischemic stroke (AIS) is a medical emergency that requires prompt recognition and streamlined work-up to ensure that time-dependent therapies are initiated to achieve the best outcomes. This article discusses frequently missed AIS in the emergency department, the role of various imagining modalities in the work-up of AIS, updates on the use of intravenous thrombolytics and endovascular therapy for AIS, pearls on supportive care management of AIS, and prehospital and hospital process improvements to shorten door-to-needle time.