Inter-hospital transfer for mechanical thrombectomy within the supraregional stroke network NEVAS

Telemedical stroke care significantly improves patient outcome in rural areas: Long-term analysis of the German NEVAS network

BACKGROUND

Comprehensive stroke centers (CSC) offer state-of-the-art stroke care in metropolitan centers. However, in rural areas, sufficient stroke expertise is much scarcer. Recently, telemedical stroke networks have offered instant consultation by stroke experts, enabling immediate administration of intravenous thrombolysis (IVT) on-site and decision on thrombectomy. While these immediate decisions are made during the consult, the impact of the network structures on stroke care in spoke hospitals is still not well described.

AIMS

This study was performed to determine if on-site performance in rural hospitals and patient outcome improve over time through participation and regular medical staff training within a telemedical stroke network.

METHODS

In this retrospective study, we analyzed data from stroke patients treated in four regional hospitals within the telemedical Neurovascular Network of Southwest Bavaria (NEVAS) between 2014 and 2019. We only included those patients that were treated in the regional hospitals until discharge at home or to neurorehabilitation. Functional outcome (modified Rankin scale) at discharge, mortality rate and periprocedural intracranial hemorrhage served as primary outcome parameters. Door-to-imaging and door-to-needle times were secondary outcome parameters.

RESULTS

In 2014-2019, 5,379 patients were treated for acute stroke with 477 receiving IVT. Most baseline characteristics were comparable over time. For all stroke patients, door-to-imaging times increased over the years, but significantly improved for potential IVT candidates and those finally treated with IVT. The percentage of patients with door-to-needle time <30 min increased from 10% to 25%. Clinical outcome at discharge improved for all stroke patients treated in the regional hospitals. Particularly for patients treated with IVT, good clinical outcome (modified Rankin scale 0-2) at discharge increased from 2014 to 2019 by 19% and mortality rates dropped from 13% to 5%.

CONCLUSIONS

24-h/7-day telemedical support and regular on-site medical staff training within a structured telemedicine stroke network such as NEVAS significantly improve on-site stroke care in rural areas, leading to a considerable benefit in clinical outcome.

DATA ACCESS STATEMENT

The data that support the findings of this study are available upon reasonable request and in compliance with the local and international ethical guidelines.

Basilar artery occlusion: drip-and-ship versus direct-to-center for mechanical thrombectomy within the Neurovascular Network of Southwest Bavaria (NEVAS)

BACKGROUND

Recent clinical trials revealed a substantial clinical benefit for mechanical thrombectomy (MT) in patients with basilar artery occlusion (BAO). While urban areas are sufficiently covered with comprehensive stroke centers and MT expertise, rural areas lack such resources. Structured telemedical stroke networks offer rural hospitals instant consultation by stroke experts, enabling swift administration of intravenous thrombolysis (IVT) on-site and transportation for MT. For BAO patients, data on performance and clinical outcomes in telemedical stroke networks are lacking.

METHODS

We retrospectively analyzed data from patients with acute BAO eligible for MT: those treated directly in our comprehensive stroke center (direct-to-center/DC) and those treated in rural hospitals that were telemedically consulted by the Neurovascular Network of Southwest Bavaria (NEVAS) and transferred to our center for MT (drip-and-ship, DS). Key time intervals, stroke management performance and functional outcome after 90 days were compared.

RESULTS

Baseline characteristics, including premorbid status and stroke severity, were comparable. Time from symptom onset to IVT was identical in both groups (118 min). There was a delay of 180 min until recanalization in DS patients, mainly due to patient transport for MT. Procedural treatment time intervals, success of recanalization and complications were comparable. Clinical outcome at 3 months follow-up of DS patients was not inferior to DC patients.

CONCLUSION

We show for the first time that patients with BAO in rural areas benefit from a structured telemedicine network such as NEVAS, regarding both on-site processing and drip-and-ship for MT. Clinical outcomes are comparable among DS and DC patients.

Geographical Requirements for the Applicability of the Results of the RACECAT Study to Other Stroke Networks

Background The RACECAT (Transfer to the Closest Local Stroke Center vs Direct Transfer to Endovascular Stroke Center of Acute Stroke Patients With Suspected Large Vessel Occlusion in the Catalan Territory) trial was the first randomized trial addressing the prehospital triage of acute stroke patients based on the distribution of thrombolysis centers and intervention centers in Catalonia, Spain. The study compared the drip-and-ship with the mothership paradigm in regions where a local thrombolysis center can be reached faster than the nearest intervention center (equipoise region). The present study aims to determine the population-based applicability of the results of the RACECAT study to 4 stroke networks with a different degree of clustering of the intervention centers (clustered, dispersed). Methods and Results Stroke networks were compared with regard to transport time saved for thrombolysis (under the drip-and-ship approach) and transport time saved for endovascular therapy (under the mothership approach). Population-based transport times were modeled with a local instance of an openrouteservice server using open data from OpenStreetMap.The fraction of the population in the equipoise region differed substantially between clustered networks (Catalonia, 63.4%; France North, 87.7%) and dispersed networks (Southwest Bavaria, 40.1%; Switzerland, 40.0%). Transport time savings for thrombolysis under the drip-and-ship approach were more marked in clustered networks (Catalonia, 29 minutes; France North, 27 minutes) than in dispersed networks (Southwest Bavaria and Switzerland, both 18 minutes). Conclusions Infrastructure differences between stroke networks may hamper the applicability of the results of the RACECAT study to other stroke networks with a different distribution of intervention centers. Stroke networks should assess the population densities and hospital type/distribution in the temporal domain before applying prehospital triage algorithms to their specific setting.

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.

Design and implementation of informatization for unified management of stroke rehabilitation in urban multi-level hospitals

Background

With the aging of the population, the prevalence and incidence of stroke in China are increasing every year. China advocates the establishment of a three-level medical service system for stroke rehabilitation, but it lacks uniform information management among all levels of medical institutions.

Objective

To achieve unified management of stroke patient rehabilitation in multilevel hospitals in the region through informatization construction.

Methods

The need for informatization of three-level stroke rehabilitation management was analyzed. Then, network connections were established, and a common rehabilitation information management system (RIMS) was developed for all levels of hospitals to enable daily stroke rehabilitation management, inter-hospitals referral, and remote video consultation. Finally, the impact on the efficiency of daily rehabilitation work, the functioning and satisfaction of stroke patients were investigated after implementing the three-level rehabilitation network.

Results

One year after implementation, 338 two-way referrals and 56 remote consultations were completed using RIMS. The stroke RIMS improved the efficiency of doctors' orders, reduced therapists' time to write medical documents, simplified statistical analysis of data and made referrals and remote consultations more convenient compared to the traditional model. The curative effect of stroke patients managed by RIMS is better than that of traditional management. Patient satisfaction with rehabilitation services in the region has increased.

Conclusion

The three-level stroke rehabilitation informatization has enabled the unified management of stroke rehabilitation in multilevel hospitals in the region. The developed RIMS improved the efficiency of daily work, improved the clinical outcomes of stroke patients, and increased patient satisfaction.

Prediction modelling the impact of onset to treatment time on the modified Rankin Scale score at 90 days for patients with acute ischaemic stroke

Introduction

Shortening the time from stroke onset to treatment increases the effectiveness of endovascular stroke therapies.

Aim

This study aimed to predict the modified Rankin Scale score at 90 days post-stroke (mRS-90d score) in patients with acute ischaemic stroke (AIS) with respect to four types of treatment: conservative therapy (CVT), intravenous thrombolysis only (IVT), mechanical thrombectomy only (MT) and pretreatment with IVT before MT (IVT+MT).

Patients and methods

This nationwide observational study included 124 484 confirmed cases of acute stroke in Sweden over 6 years (2012–2017). The associations between onset-to-treatment time (OTT), patient age and hospital admission National Institutes of Health Stroke Scale (NIHSS) score with the five-levelled mRS-90d score were retrospectively studied. A generalised linear model (GLM) was fitted to predict the mRS-90d scores for each patient group.

Results

The fitted GLM for CVT patients is a function of age and NIHSS score. For IVT, MT and IVT+MT patients, GLMs additionally employed OTT variables. By reducing the mean OTTs by 15 min, the number needed-to-treat (NNT) for one patient to make a favourable one-step shift in the mRS was 30 for IVT, 48 for MT and 21 for IVT+MT.

Discussion and conclusion

This study demonstrates linear associations of mRS-90d score with OTT for IVT, MT and IVT+MT, and shows in absolute effects measures that OTT reductions for IVT and/or MT produces substantial health gains for patients with AIS. Even moderate OTT reductions led to sharp drops in the NNT.

Stroke care networks and the impact on quality of care

Lack of rapidly available neurological expertise, especially in rural areas, is one of the key obstacles in stroke care. Stroke care networks attempt to address this challenge by connecting hospitals with specialized stroke centers, stroke units, and hospitals of lower levels of care. While the benefits of stroke care networks are well-documented, travel distances are likely to increase when patients are transferred almost exclusively between members of the same network. This is particularly important for patients who require mechanical thrombectomy, an increasingly employed treatment method that requires equipment and expertise available in specialized stroke centers. This study aims to analyze the performance of the current design of stroke care networks in Bavaria, Germany, and to evaluate the improvement potential when the networks are redesigned to minimize travel distances. To this end, we define three fundamental criteria for assessing network design performance: 1) average travel distances, 2) the populace in the catchment area relative to the number of stroke units, and 3) the ratio of stroke units to lower-care hospitals. We generate several alternative stroke network designs using an analytical approach based on mathematical programming and clustering. Finally, we evaluate the performance of the existing networks in Bavaria via simulation. The results show that the current network design could be significantly improved concerning the average travel distances. Moreover, the existing networks are unnecessarily imbalanced when it comes to their number of stroke units per capita and the ratio of stroke units to lower-care hospitals.

Guillain-Barré syndrome spectrum associated with COVID-19: an up-to-date systematic review of 73 cases

Since coronavirus disease-2019 (COVID-19) outbreak in January 2020, several pieces of evidence suggested an association between the spectrum of Guillain-Barré syndrome (GBS) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Most findings were reported in the form of case reports or case series, whereas a comprehensive overview is still lacking. We conducted a systematic review and searched for all published cases until July 20th 2020. We included 73 patients reported in 52 publications. A broad age range was affected (mean 55, min 11-max 94 years) with male predominance (68.5%). Most patients showed respiratory and/or systemic symptoms, and developed GBS manifestations after COVID-19. However, asymptomatic cases for COVID-19 were also described. The distributions of clinical variants and electrophysiological subtypes resemble those of classic GBS, with a higher prevalence of the classic sensorimotor form and the acute inflammatory demyelinating polyneuropathy, although rare variants like Miller Fisher syndrome were also reported. Cerebrospinal fluid (CSF) albuminocytological dissociation was present in around 71% cases, and CSF SARS-CoV-2 RNA was absent in all tested cases. More than 70% of patients showed a good prognosis, mostly after treatment with intravenous immunoglobulin. Patients with less favorable outcome were associated with a significantly older age in accordance with previous findings regarding both classic GBS and COVID-19. COVID-19-associated GBS seems to share most features of classic post-infectious GBS and possibly the same immune-mediated pathogenetic mechanisms. Nevertheless, more extensive epidemiological studies are needed to clarify these issues.