Impact of interhospital transfer on patients undergoing endovascular thrombectomy for acute ischaemic stroke in an Australian setting

Prehospital Detection of Large Vessel Occlusion Stroke With EEG

BACKGROUND AND OBJECTIVES

Endovascular thrombectomy (EVT) is standard treatment for anterior large vessel occlusion stroke (LVO-a stroke). Prehospital diagnosis of LVO-a stroke would reduce time to EVT by allowing direct transportation to an EVT-capable hospital. We aim to evaluate the diagnostic accuracy of dry electrode EEG for the detection of LVO-a stroke in the prehospital setting.

METHODS

ELECTRA-STROKE was an investigator-initiated, prospective, multicenter, diagnostic study, performed in the prehospital setting. Adult patients were eligible if they had suspected stroke (as assessed by the attending ambulance nurse) and symptom onset <24 hours. A single dry electrode EEG recording (8 electrodes) was performed by ambulance personnel. Primary endpoint was the diagnostic accuracy of the theta/alpha frequency ratio for LVO-a stroke (intracranial ICA, A1, M1, or proximal M2 occlusion) detection among patients with EEG data of sufficient quality, expressed as the area under the receiver operating characteristic curve (AUC). Secondary endpoints were diagnostic accuracies of other EEG features quantifying frequency band power and the pairwise derived Brain Symmetry Index. Neuroimaging was assessed by a neuroradiologist blinded to EEG results.

RESULTS

Between August 2020 and September 2022, 311 patients were included. The median EEG duration time was 151 (interquartile range [IQR] 151-152) seconds. For 212/311 (68%) patients, EEG data were of sufficient quality for analysis. The median age was 74 (IQR 66-81) years, 90/212 (42%) were women, and the median baseline NIH Stroke Scale was 1 (IQR 0-4). Six (3%) patients had an LVO-a stroke, 109/212 (51%) had a non-LVO-a ischemic stroke, 32/212 (15%) had a transient ischemic attack, 8/212 (4%) had a hemorrhagic stroke, and 57/212 (27%) had a stroke mimic. AUC of the theta/alpha ratio was 0.80 (95% CI 0.58-1.00). Of the secondary endpoints, the pairwise derived Brain Symmetry Index in the delta frequency band had the highest diagnostic accuracy (AUC 0.91 [95% CI 0.73-1.00], sensitivity 80% [95% CI 38%-96%], specificity 93% [95% CI 88%-96%], positive likelihood ratio 11.0 [95% CI 5.5-21.7]).

DISCUSSION

The data from this study suggest that dry electrode EEG has the potential to detect LVO-a stroke among patients with suspected stroke in the prehospital setting. Toward future implementation of EEG in prehospital stroke care, EEG data quality needs to be improved.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov identifier: NCT03699397.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that prehospital dry electrode scalp EEG accurately detects LVO-a stroke among patients with suspected acute stroke.

Fast track to stroke unit for patients not eligible for acute intervention, a case-control register study on 1066 patients

Stroke patients not eligible for acute intervention often have low priority and may spend long time at the emergency department (ED) waiting for admission. The aim of this retrospective case-control register study was to evaluate outcomes for such "low priority" stroke patients who were transported via Fast Track directly to the stroke unit, according to pre-specified criteria by emergency medical service (EMS). The outcomes of Fast Track patients, transported directly to stroke unit (cases) were compared with the outcomes of patients who fulfilled these critera for Fast Track, but instead were transported to the ED (controls). In all, 557 cases and 509 controls were identified. The latter spent a mean time of 237 min in the ED before admission. The 90-day mortality rate was 12.9% for cases and 14.7% for controls (n.s.). None of the secondary outcome events differed significantly between the groups: 28-day mortality rate; death rate during hospitalisation; proportion of pneumonias, falls or pressure ulcers; or health-related outcomes according to the EQ-5D-5L questionnaire. These findings indicates that the Fast Track to the stroke unit by an EMS is safe for selected stroke patients and could avoid non-valuable time in the ED.

Subhairline Electroencephalography for the Detection of Large Vessel Occlusion Stroke

BACKGROUND

Endovascular thrombectomy is standard treatment for patients with anterior circulation large vessel occlusion stroke (LVO-a). Prehospital identification of these patients would enable direct routing to an endovascular thrombectomy-capable hospital and consequently reduce time-to-endovascular thrombectomy. Electroencephalography (EEG) has previously proven to be promising for LVO-a stroke detection. Fast and reliable electrode application, however, can remain a challenge. A potential alternative is subhairline EEG. We evaluated the diagnostic accuracy of subhairline EEG for LVO-a stroke detection.

METHODS AND RESULTS

We included adult patients with a suspected stroke or known LVO-a stroke and symptom onset time <24 hours. A single 3-minute EEG recording was performed at the emergency department, before endovascular thrombectomy, using 9 self-adhesive electrodes placed on the forehead and behind the ears. We evaluated the diagnostic accuracies of EEG features quantifying frequency band power and brain symmetry (pairwise derived Brain Symmetry Index) for LVO-a stroke detection using receiver operating characteristic analysis. EEG data were of sufficient quality for analysis in 51/52 (98%) included patients. Of these patients, 16 (31%) had an LVO-a stroke, 16 (31%) a non-LVO-a ischemic stroke, 5 (10%) a transient ischemic attack, and 14 (27%) a stroke mimic. Median symptom-onset-to-EEG-time was 266 (interquartile range 130-709) minutes. The highest diagnostic accuracy for LVO-a stroke detection was reached by the pairwise derived Brain Symmetry Index in the theta frequency band (area under the receiver operating characteristic curve 0.90; sensitivity 86%; specificity 83%).

CONCLUSIONS

Subhairline EEG could detect LVO-a stroke with high diagnostic accuracy and had high data reliability. These data suggest that subhairline EEG is potentially suitable as a prehospital stroke triage instrument.

Functional outcomes of patients with ischaemic stroke with known atrial fibrillation not on therapeutic anticoagulation

BACKGROUND

Anticoagulation significantly reduces the risk of ischaemic stroke in patients with atrial fibrillation (AF). There are a proportion of patients with known AF who remain off anticoagulation. Aims This study aims to retrospectively compare the baseline characteristics, treatments and functional outcomes between patients with ischaemic stroke and known AF based on their anticoagulation status.

METHODS

A single-centre, retrospective review of consecutive patients with an ischaemic stroke and a known history of AF was conducted.

RESULTS

Two hundred four patients with an ischaemic stroke had documented AF prior to the index admission, of which 126 were anticoagulated. Median admission National Institutes of Health Stroke Scale score was lower for anticoagulated patients, though not statistically significant (5.1 vs 7.0, P = 0.09). Median baseline modified Rankin score (mRS) did not significantly differ. Nonanticoagulated patients were more likely to have large vessel occlusions (37.2% vs 23.8%, P = 0.04) and more likely to receive intravenous thrombolysis (15.4% vs 1.6%, P < 0.01). There was no difference in rates of endovascular clot retrieval between groups (P > 0.05). Unfavourable functional outcome at 90 days (mRS ≥ 3) did not significantly differ between groups (P = 0.51). A total of 38.5% of nonanticoagulated patients had no documented reason for this. Of the patients who survived the index admission, 81.5% of patients who were not anticoagulated on admission received anticoagulation.

CONCLUSIONS

Baseline anticoagulation was associated with milder stroke severity in ischaemic stroke patients with known AF. There was no significant difference in functional outcomes at 90 days between groups. Larger observational studies are required to further assess this cohort.

Modern Prehospital Screening Technology for Emergent Neurovascular Disorders

Stroke is a serious neurological disease and a significant contributor to disability worldwide. Traditional in-hospital imaging techniques such as computed tomography (CT) and magnetic resonance imaging (MRI) remain the standard modalities for diagnosing stroke. The development of prehospital stroke detection devices may facilitate earlier diagnosis, initiation of stroke care, and ultimately better patient outcomes. In this review, the authors summarize the features of eight stroke detection devices using noninvasive brain scanning technology. The review summarizes the features of stroke detection devices including portable CT, MRI, transcranial Doppler ultrasound , microwave tomographic imaging, electroencephalography, near-infrared spectroscopy, volumetric impedance phaseshift spectroscopy, and cranial accelerometry. The technologies utilized, the indications for application, the environments indicated for application, the physical features of the eight stroke detection devices, and current commercial products are discussed. As technology advances, multiple portable stroke detection instruments exhibit the promising potential to expedite the diagnosis of stroke and enhance the time taken for treatment, ultimately aiding in prehospital stroke triage.

Clinical outcomes of delayed mechanical thrombectomy: Descriptive analysis and development of a screening tool

BACKGROUND AND PURPOSE

Limited data guide the selection of patients with large vessel occlusion ischaemic stroke who may benefit from referral to a distant tertiary centre for mechanical thrombectomy (MT). We aimed to characterize this population, describe clinical outcomes and develop a screening system to identify patients most likely to benfit from delayed mechanical thrombectomy (MT).

METHODS

We undertook a retrospective cohort analysis enrolling patients transferred from regional sites to one of two MT comprehensive stroke units with a time from non-contrast computed tomography (NCCT) of the brain to reperfusion of 4 h or more. We describe Alberta Stroke Programme Early Computed Tomography Score (ASPECTS), National Institute of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) in our patients and compare these patients to those in extended-time-window trials. Lastly, we developed and validated a scoring model to help clinicians identify appropriate patients based on variables associated with poor outcomes.

RESULTS

We included 563 patients, 46% of whom received thrombolysis; the median (interquartile range [IQR]) ASPECTS was 8 (7-10) and the median (IQR) NIHSS score was 16 (11-20). The median (IQR) symptom to mechanical reperfusion time was 390 (300-580) min. Eight patients (1%) had a symptomatic haemorrhage. We achieved good clinical outcome (defined as mRS score ≤2) in 299 patients (54%). Age, diabetes, NIHSS score and ASPECTS were used to create a weighted scoring system with a validated area under the curve of 0.83 (95% confidence interval 0.74-0.92).

CONCLUSION

Our study shows, in highly selected patients, that delayed MT many hours after baseline NCCT is associated with good clinical outcomes. However, older patients with diabetes, high NIHSS score and low ASPECTS may not benefit from transfer to a hub centre many hours away for MT in this model of care.

Optimal CT perfusion thresholds for core and penumbra in acute posterior circulation infarction

Background

At least 20% of strokes involve the posterior circulation (PC). Compared to the anterior circulation, posterior circulation infarction (POCI) are frequently misdiagnosed. CT perfusion (CTP) has advanced stroke care by improving diagnostic accuracy and expanding eligibility for acute therapies. Clinical decisions are predicated upon precise estimates of the ischaemic penumbra and infarct core. Current thresholds for defining core and penumbra are based upon studies of anterior circulation stroke. We aimed to define the optimal CTP thresholds for core and penumbra in POCI.

Methods

Data were analyzed from 331-patients diagnosed with acute POCI enrolled in the International-stroke-perfusion-registry (INSPIRE). Thirty-nine patients with baseline multimodal-CT with occlusion of a large PC-artery and follow up diffusion weighted MRI at 24-48 h were included. Patients were divided into two-groups based on artery-recanalization on follow-up imaging. Patients with no or complete recanalisation were used for penumbral and infarct-core analysis, respectively. A Receiver operating curve (ROC) analysis was used for voxel-based analysis. Optimality was defined as the CTP parameter and threshold which maximized the area-under-the-curve. Linear regression was used for volume based analysis determining the CTP threshold which resulted in the smallest mean volume difference between the acute perfusion lesion and follow up MRI. Subanalysis of PC-regions was performed.

Results

Mean transit time (MTT) and delay time (DT) were the best CTP parameters to characterize ischaemic penumbra (AUC = 0.73). Optimal thresholds for penumbra were a DT >1 s and MTT>145%. Delay time (DT) best estimated the infarct core (AUC = 0.74). The optimal core threshold was a DT >1.5 s. The voxel-based analyses indicated CTP was most accurate in the calcarine (Penumbra-AUC = 0.75, Core-AUC = 0.79) and cerebellar regions (Penumbra-AUC = 0.65, Core-AUC = 0.79). For the volume-based analyses, MTT >160% demonstrated best correlation and smallest mean-volume difference between the penumbral estimate and follow-up MRI (R ² = 0.71). MTT >170% resulted in the smallest mean-volume difference between the core estimate and follow-up MRI, but with poor correlation (R ² = 0.11).

Conclusion

CTP has promising diagnostic utility in POCI. Accuracy of CTP varies by brain region. Optimal thresholds to define penumbra were DT >1 s and MTT >145%. The optimal threshold for core was a DT >1.5 s. However, CTP core volume estimates should be interpreted with caution.

Time-to-care metrics in patients with interhospital transfer for mechanical thrombectomy in north-east Germany: Primary telestroke centers in rural areas vs. primary stroke centers in a metropolitan area

Background

Mechanical thrombectomy (MT) is highly effective in large vessel occlusion (LVO) stroke. In north-east Germany, many rural hospitals do not have continuous neurological expertise onsite and secondary transport to MT capable comprehensive stroke centers (CSC) is necessary. In metropolitan areas, small hospitals often have neurology departments, but cannot perform MT. Thus, interhospital transport to CSCs is also required. Here, we compare time-to-care metrics and outcomes in patients receiving MT after interhospital transfer from primary stroke centers (PCSs) to CSCs in rural vs. metropolitan areas.

Methods

Patients from ten rural telestroke centers (RTCs) and nine CSCs participated in this study under the quality assurance registry for thrombectomies of the Acute Neurological care in North-east Germany with TeleMedicine (ANNOTeM) telestroke network. For the metropolitan area, we included patients admitted to 13 hospitals without thrombectomy capabilities (metropolitan primary stroke centers, MPSCs) and transferred to two CSCs. We compared groups regarding baseline variables, time-to-care metrics, clinical, and technical outcomes.

Results

Between October 2018 and June 2022, 50 patients were transferred from RTCs within the ANNOTeM network and 42 from MPSCs within the Berlin metropolitan area. RTC patients were older (77 vs. 72 yrs, p = 0.05) and had more severe strokes (NIHSS 17 vs. 10 pts., p < 0.01). In patients with intravenous thrombolysis (IVT; 34.0 and 40.5%, respectively), time from arrival at the primary stroke center to start of IVT was longer in RTCs (65 vs. 37 min, p < 0.01). However, RTC patients significantly quicker underwent groin puncture at CSCs (door-to-groin time: 42 vs. 60 min, p < 0.01). Despite longer transport distances from RTCs to CSCs (55 vs. 22 km, p < 0.001), there was no significant difference of times between arrival at the PSC and groin puncture (210 vs. 208 min, p = 0.96). In adjusted analyses, there was no significant difference in clinical and technical outcomes.

Conclusion

Despite considerable differences in the setting of stroke treatment in rural and metropolitan areas, overall time-to-care metrics were similar. Targets of process improvement should be door-to-needle times in RTCs, transfer organization, and door-to-groin times in CSCs wherever such process times are above best-practice models.

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.

Practical utility of the ACT-FAST triage algorithm from a primary stroke centre perspective

Background: Rapid reperfusion in ischaemic stroke with emergent large vessel occlusion (ELVO) reduces morbidity and mortality. Limited distribution of endovascular clot retrieval (ECR) capable comprehensive stroke centres (CSCs) necessitates development of pre-hospital models of care to provide equitable and economical access to reperfusion therapy. We examine the time metrics of the traditional secondary transfer strategy in comparison to the direct bypass strategy and the potential utility of the ACT-FAST prehospital triage algorithm on a large volume Melbourne primary stroke centre (PSC).

Method: Retrospective analysis of consecutive patients presenting to a PSC from 1 January 2020 to 31 December 2020. Clinical records were interrogated for ACT-FAST positive patients. Time metrics were established using Google Maps traffic modelling and local/published door-to-needle, door-in-door out and door-to-groin data.

Results: 88 patients during the study period were ACT-FAST positive. Of these, 49/88 (56%) cases had ELVO ischaemic strokes, 24/88 (27%) cases had intracranial haemorrhages and the remaining 15/88 (17%) had non ELVO ischaemic strokes or mimics (seizure, complex migraine, etc). 28/88 (32%) cases met indication for and were subsequently transferred to a CSC for consideration of ECR. The modelled median scene to groin time for the direct bypass strategy is 94 min whereas the median scene to groin time for the secondary transfer strategy is 109 min, giving a difference of 15 min.

Conclusion: Time savings to groin puncture for the direct bypass strategy is substantially less than previous estimates and suggests that the secondary transfer strategy continues to be a viable pathway for a high efficiency PSC.

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).

TACTICS - Trial of Advanced CT Imaging and Combined Education Support for Drip and Ship: evaluating the effectiveness of an 'implementation intervention' in providing better patient access to reperfusion therapies: protocol for a non-randomised controlled stepped wedge cluster trial in acute stroke

INTRODUCTION

Stroke reperfusion therapies, comprising intravenous thrombolysis (IVT) and/or endovascular thrombectomy (EVT), are best practice treatments for eligible acute ischemic stroke patients. In Australia, EVT is provided at few, mainly metropolitan, comprehensive stroke centres (CSC). There are significant challenges for Australia's rural and remote populations in accessing EVT, but improved access can be facilitated by a 'drip and ship' approach. TACTICS (Trial of Advanced CT Imaging and Combined Education Support for Drip and Ship) aims to test whether a multicomponent, multidisciplinary implementation intervention can increase the proportion of stroke patients receiving EVT.

METHODS AND ANALYSIS

This is a non-randomised controlled, stepped wedge trial involving six clusters across three Australian states. Each cluster comprises one CSC hub and a minimum of three primary stroke centre (PSC) spokes. Hospitals will work in a hub and spoke model of care with access to a multislice CT scanner and CT perfusion image processing software (MIStar, Apollo Medical Imaging). The intervention, underpinned by behavioural theory and technical assistance, will be allocated sequentially, and clusters will move from the preintervention (control) period to the postintervention period.

PRIMARY OUTCOME

Proportion of all stroke patients receiving EVT, accounting for clustering.

SECONDARY OUTCOMES

Proportion of patients receiving IVT at PSCs, proportion of treated patients (IVT and/or EVT) with good (modified Rankin Scale (mRS) score 0-2) or poor (mRS score 5-6) functional outcomes and European Quality of Life Scale scores 3 months postintervention, proportion of EVT-treated patients with symptomatic haemorrhage, and proportion of reperfusion therapy-treated patients with good versus poor outcome who presented with large vessel occlusion at spokes.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Hunter New England Human Research Ethics Committee (18/09/19/4.13, HREC/18/HNE/241, 2019/ETH01238). Trial results will be disseminated widely through published manuscripts, conference presentations and at national and international platforms regardless of whether the trial was positive or neutral.

TRIAL REGISTRATION NUMBER

ACTRN12619000750189; UTNU1111-1230-4161.

Relationship between primary stroke center volume and time to endovascular thrombectomy in acute ischemic stroke

Background and purpose

We investigated whether the annual volume of patients with acute ischemic stroke referred from a primary stroke center (PSC) for endovascular treatment (EVT) is associated with treatment times and functional outcome.

Methods

We used data from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) registry (2014–2017). We included patients with acute ischemic stroke of the anterior circulation who were transferred from a PSC to a comprehensive stroke center (CSC) for EVT. We examined the association between EVT referral volume of PSCs and treatment times and functional outcome using multivariable regression modeling. The main outcomes were time from arrival at the PSC to groin puncture (PSC‐door‐to‐groin time), adjusted for estimated ambulance travel times, time from arrival at the CSC to groin puncture (CSC‐door‐to‐groin time), and modified Rankin Scale (mRS) score at 90 days after stroke.

Results

Of the 3637 patients in the registry, 1541 patients (42%) from 65 PSCs were included. Mean age was 71 years (SD ± 13.3), median National Institutes of Health Stroke Scale score was 16 (interquartile range [IQR]: 12–19), and median time from stroke onset to arrival at the PSC was 53 min (IQR: 38–90). Eighty‐three percent had received intravenous thrombolysis. EVT referral volume was not associated with PSC‐door‐to‐groin time (adjusted coefficient: −0.49 min/annual referral, 95% confidence interval [CI]: −1.27 to 0.29), CSC‐door‐to‐groin time (adjusted coefficient: −0.34 min/annual referral, 95% CI: −0.69 to 0.01) or 90‐day mRS score (adjusted common odds ratio: 0.99, 95% CI: 0.96–1.01).

Conclusions

In patients transferred from a PSC for EVT, higher PSC volumes do not seem to translate into better workflow metrics or patient outcome.

Effect of prehospital workflow optimization on treatment delays and clinical outcomes in acute ischemic stroke: A systematic review and meta-analysis

BACKGROUND

The prehospital phase is critical in ensuring that stroke treatment is delivered quickly and is a major source of time delay. This study sought to identify and examine prehospital stroke workflow optimizations (PSWOs) and their impact on improving health systems, reperfusion rates, treatment delays, and clinical outcomes.

METHODS

The authors conducted a systematic literature review and meta-analysis by extracting data from several research databases (PubMed, Cochrane, Medline, and Embase) published since 2005. We used appropriate key search terms to identify clinical studies concerning prehospital workflow optimization, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

The authors identified 27 articles that looked at the impact of prehospital workflow optimizations on time and treatment parameters; 26 were included in the meta-analysis. The PSWO were subgrouped into three categories: improved intravenous thrombolysis (IVT) triage, large-vessel occlusion (LVO) bypass, and mobile stroke unit (MSU). The salient findings are as follows: improved IVT triage led to significantly improved rates of IVT (relative risk [RR] = 1.80, 95% confidence interval [CI] = 1.18 to 2.75); however, MSU did not (RR = 1.22, 95% CI = 0.98 to 1.52). Improved IVT triage (standard mean difference [SMD] = -0.82, 95% CI = -1.32 to -0.32), LVO bypass (SMD = -0.80, 95% CI = -1.13 to -0.47), and MSU (SMD = -0.87, 95% CI = -1.57 to -0.17) were found to significantly reduce door-to-needle time for IVT. MSU was found to significantly reduce call-to-needle (SMD = -1.41, 95% CI = -1.94 to -0.88) and onset-to-needle (SMD = -1.15, 95% CI = -1.74 to -0.56) times for IVT. MSU additionally demonstrated significant reduction in door-to-perfusion (SMD = -0.72, 95% CI = -1.32 to -0.12) as well as call-to-perfusion (SMD = -0.73, 95% CI = -1.08 to -0.38) times for EVT. Finally, PSWO did not demonstrate significant improvements in rates of good functional outcome (RR = 1.04, 95% CI = 0.97 to 1.12) or mortality at 90 days (RR = 1.00, 95% CI = 0.76 to 1.31).

CONCLUSIONS

This systematic review and meta-analysis found that PSWO significantly improves several time metrics related to stroke treatment leading to improvement in IVT reperfusion rates. Thus, the implementation of these measures in stroke networks is a promising avenue to improve an often-neglected aspect of the stroke response. However, the limited available data suggest functional outcomes and mortality are not significantly improved by PSWO; hence, further studies and improvement strategies vis-à-vis PSWOs are warranted.

Long-Term Outcomes of Acute Endovascular Thrombectomy: Tokyo/tama-Registry of Acute Endovascular Thrombectomy (TREAT)

OBJECTIVE

Mechanical thrombectomy (MT) is the recommended treatment for patients with acute ischemic stroke due to large cerebral vessel occlusion (LVO). However, few studies have investigated long-term outcomes after MT. The aim of this study was to investigate functional outcomes at long-term follow-up (1 year after MT) in patients undergoing MT for anterior circulation LVO in real-world clinical practice.

METHODS

This was a retrospective and prospective observational study using data from TREAT (Tokyo/tama-Registry of Acute Endovascular Thrombectomy), a multicenter registry of MT for acute LVO in the Tokyo metropolitan area. All subjects emergently transferred and treated with MT from January 2015 to December 2018 were selected. Patients' baseline characteristics and stroke-related parameters were evaluated. The primary outcome was the modified Rankin Scale (mRS) score 1 year after MT. The secondary outcomes were risk factors for long-term good outcomes (mRS score 0-2); transfer system (stroke bypass vs. secondary transfer) was also evaluated as a potential factor associated with good long-term outcomes.

RESULTS

A total of 162 cases (mean age 73.0 years, age range 30-97 years; 59.9% male) whose mRS scores at 1 year were obtained were analyzed. The median admission National Institutes of Health Stroke Scale (NIHSS) score was 17. Overall, 42.6% of the patients achieved functional independence at 1-year follow-up. Lower initial NIHSS score and mRS score 0-2 at 90 days were the independent predictors for good long-term outcomes. Stroke bypass was associated with a higher initial NIHSS score and mRS score 0 at 1 year.

CONCLUSIONS

A significant number of patients experience a good long-term outcome after MT.