Martin Lesmeister

Diagnosis and treatment of patients with stroke in a mobile stroke unit versus in hospital: a randomised controlled trial.

BACKGROUND Only 2-5% of patients who have a stroke receive thrombolytic treatment, mainly because of delay in reaching the hospital. We aimed to assess the efficacy of a new approach of diagnosis and treatment starting at the emergency site, rather than after hospital arrival, in reducing delay in stroke therapy. METHODS We did a randomised single-centre controlled trial to compare the time from alarm (emergency call) to therapy decision between mobile stroke unit (MSU) and hospital intervention. For inclusion in our study patients needed to be aged 18-80 years and have one or more stroke symptoms that started within the previous 2·5 h. In accordance with our week-wise randomisation plan, patients received either prehospital stroke treatment in a specialised ambulance (equipped with a CT scanner, point-of-care laboratory, and telemedicine connection) or optimised conventional hospital-based stroke treatment (control group) with a 7 day follow-up. Allocation was not masked from patients and investigators. Our primary endpoint was time from alarm to therapy decision, which was analysed with the Mann-Whitney U test. Our secondary endpoints included times from alarm to end of CT and to end of laboratory analysis, number of patients receiving intravenous thrombolysis, time from alarm to intravenous thrombolysis, and neurological outcome. We also assessed safety endpoints. This study is registered with ClinicalTrials.gov, number NCT00153036. FINDINGS We stopped the trial after our planned interim analysis at 100 of 200 planned patients (53 in the prehospital stroke treatment group, 47 in the control group), because we had met our prespecified criteria for study termination. Prehospital stroke treatment reduced the median time from alarm to therapy decision substantially: 35 min (IQR 31-39) versus 76 min (63-94), p<0·0001; median difference 41 min (95% CI 36-48 min). We also detected similar gains regarding times from alarm to end of CT, and alarm to end of laboratory analysis, and to intravenous thrombolysis for eligible ischaemic stroke patients, although there was no substantial difference in number of patients who received intravenous thrombolysis or in neurological outcome. Safety endpoints seemed similar across the groups. INTERPRETATION For patients with suspected stroke, treatment by the MSU substantially reduced median time from alarm to therapy decision. The MSU strategy offers a potential solution to the medical problem of the arrival of most stroke patients at the hospital too late for treatment. FUNDING Ministry of Health of the Saarland, Germany, the Werner-Jackstädt Foundation, the Else-Kröner-Fresenius Foundation, and the Rettungsstiftung Saar.

Point‐of‐care laboratory halves door‐to‐therapy‐decision time in acute stroke

Currently, stroke laboratory examinations are usually performed in the centralized hospital laboratory, but often planned thrombolysis is given before all results are available, to minimize delay. In this study, we examined the feasibility of gaining valuable time by transferring the complete stroke laboratory workup required by stroke guidelines to a point‐of‐care laboratory system, that is, placed at a stroke treatment room contiguous to the computed tomography, where the patients are admitted and where they obtain neurological, laboratory, and imaging examinations and treatment by the same dedicated team. Our results showed that reconfiguration of the entire stroke laboratory analysis to a point‐of‐care system was feasible for 200 consecutively admitted patients. This strategy reduced the door‐to‐therapy‐decision times from 84 ± 26 to 40 ± 24 min (p < 0.001). Results of most laboratory tests (except activated partial thromboplastin time and international normalized ratio) revealed close agreement with results from a standard centralized hospital laboratory. These findings may offer a new solution for the integration of laboratory workup into routine hyperacute stroke management. Ann Neurol 2011;

Is Prehospital Treatment of Acute Stroke too Expensive An Economic Evaluation Based on the First Trial

Background: Recently, a strategy for treating stroke directly at the emergency site was developed. It was based on the use of an ambulance equipped with a scanner, a point-of-care laboratory, and telemedicine capabilities (Mobile Stroke Unit). Despite demonstrating a marked reduction in the delay to thrombolysis, this strategy is criticized because of potentially unacceptable costs. Methods: We related the incremental direct costs of prehospital stroke treatment based on data of the first trial on this concept to one year direct cost savings taken from published research results. Key parameters were configuration of emergency medical service personnel, operating distance, and population density. Model parameters were varied to cover 5 different relevant emergency medical service scenarios. Additionally, the effects of operating distance and population density on benefit-cost ratios were analyzed. Results: Benefits of the concept of prehospital stroke treatment outweighed its costs with a benefit-cost ratio of 1.96 in the baseline experimental setting. The benefit-cost ratio markedly increased with the reduction of the staff and with higher population density. Maximum benefit-cost ratios between 2.16 and 6.85 were identified at optimum operating distances in a range between 43.01 and 64.88 km (26.88 and 40.55 miles). Our model implies that in different scenarios the Mobile Stroke Unit strategy is cost-efficient starting from an operating distance of 15.98 km (9.99 miles) or from a population density of 79 inhabitants per km2 (202 inhabitants per square mile). Conclusion: This study indicates that based on a one-year benefit-cost analysis that prehospital treatment of acute stroke is highly cost-effective across a wide range of possible scenarios. It is the highest when the staff size of the Mobile Stroke Unit can be reduced, for example, by the use of telemedical support from hospital experts. Although efficiency is positively related to population density, benefit-cost ratios can be greater than 1 even in rural settings.

Prehospital Imaging-Based Triage of Head Trauma with a Mobile Stroke Unit: First Evidence and Literature Review.

An ambulance equipped with a computed tomography (CT) scanner, point‐of‐care laboratory, and telemedicine capabilities (Mobile Stroke Unit [MSU]) has been shown to enable delivery of thrombolysis to stroke patients at the emergency site, thereby significantly decreasing time to treatment. However, the MSU frequently assesses patients with cerebral disorders other than stroke. For some of these disorders, prehospital CT scanning may also be beneficial.

First Automated Stroke Imaging Evaluation via Electronic Alberta Stroke Program Early CT Score in a Mobile Stroke Unit.

Background: Recently, a mobile stroke unit (MSU) was shown to facilitate acute stroke treatment directly at the emergency site. The neuroradiological expertise of the MSU is improved by its ability to detect early ischemic damage via automatic electronic (e) evaluation of CT scans using a novel software program that calculates the electronic Alberta Stroke Program Early CT Score (e-ASPECTS). Methods: The feasibility of integrating e-ASPECTS into an ambulance was examined, and the clinical integration and utility of the software in 15 consecutive cases evaluated. Results: Implementation of e-ASPECTS onto the MSU and into the prehospital stroke management was feasible. The values of e-ASPECTS matched with the results of conventional neuroradiologic analysis by the MSU team. The potential benefits of e-ASPECTS were illustrated by three cases. In case 1, excluding early infarct signs supported the decision to directly perform prehospital thrombolysis. In case 2, in which stroke was caused by large-vessel occlusion, the high e-ASPECTS value supported the decision to initiate intra-arterial treatment and triage the patient to a comprehensive stroke center. In case 3, the e-ASPECTS value was 10, indicating the absence of early infarct signs despite pre-existing cerebral microangiopathy and macroangiopathy, a finding indicating the programs robustness against artefacts. Conclusions: This study on the integration of e-ASPECTS into the prehospital stroke management via a MSU showed for the first time that such integration is feasible, and aids both decision regarding the treatment option and the triage regarding the most appropriate target hospital.

Standard operating procedures improve acute neurologic care in a sub-Saharan African setting

Objective: Quality of neurologic emergency management in an under-resourced country may be improved by standard operating procedures (SOPs). Methods: Neurologic SOPs were implemented in a large urban (Banjul) and a small rural (Brikama) hospital in the Gambia. As quality indicators of neurologic emergency management, performance of key procedures was assessed at baseline and in the first and second implementation years. Results: At Banjul, 100 patients of the first-year intervention group exhibited higher rates of general procedures of emergency management than 105 control patients, such as neurologic examination (99.0% vs 91.4%; p < 0.05) and assessments of respiratory rate (98.0% vs 81.9%, p < 0.001), temperature (60.0% vs 36.2%; p < 0.001), and glucose levels (73.0% vs 58.1%; p < 0.05), in addition to written directives by physicians (96.0% vs 88.6%, p < 0.05), whereas assessments of other vital signs remained unchanged. In stroke patients, rates of stroke-related procedures increased: early CT scanning (24.3% vs 9.9%; p < 0.05), blood count (73.0% vs 49.3%; p < 0.01), renal and liver function tests (50.0% vs 5.6%, p < 0.001), aspirin prophylaxis (47.3% vs 9.9%; p < 0.001), and physiotherapy (41.9% vs 4.2%; p < 0.001). Most effects persisted until the second-year evaluation. SOP implementation was similarly feasible and beneficial at the Brikama hospital. However, outcomes did not significantly differ in the hospitals. Conclusions: Implementing SOPs is a realistic, low-cost option for improving process quality of neurologic emergency management in under-resourced settings. Classification of evidence: This study provides Class IV evidence that, for patients with suspected neurologic emergencies in sub-Saharan Africa, neurologic SOPs increase the rate of performance of guideline-recommended procedures.

Transorbital Sonography and Visual Outcome for the Diagnosis and Monitoring of Optic Neuritis

Transorbital sonography (TOS) is a promising tool to support the clinical diagnosis of optic neuritis (ON) by showing thickening of optic nerve. In this study, we aimed to define its specific role in follow‐up of ON patients.

Dosage Calculation for Intravenous Thrombolysis of Ischemic Stroke: To Weigh or to Estimate

Background: Estimation is a widely used method of assessing the weight of patients with acute stroke. Because the dosage of tissue plasminogen activator (tPA) is weight-dependent, errors in estimation lead to incorrect dosing. Methods: We installed a ground-level scale in the computed tomography (CT) suite of our hospital and also integrated a scale into the CT table of our Mobile Stroke Unit in order to prospectively assess the differences between reported, estimated, and measured weights of acute stroke patients. An independent rater asked patients to report their weight. The patients’ weights were also estimated by the treating physician and measured with a scale. Differences between reported, estimated, and measured weights were analyzed statistically. Results: For 100 consecutive patients, weighing was possible without treatment delays. Weights estimated by the physician diverged from measured weights by 10% or more for 27 patients and by 20% or more for 6 patients. Weights reported by the patient diverged from measured weights by 10% or more for 12 patients. Weights reported by the patients differed significantly less from measured weights (mean, 4.1 ± 3.1 kg) than did weights estimated by the physician (5.7 ± 4.4 kg; p = 0.003). Conclusion: This first prospective study of weight assessment in acute stroke shows that the use of an easily accessible scale makes it feasible to weigh patients with acute stroke without the treatment delay associated with additional patient transfers. Physicians’ estimates of patients’ weights demonstrated substantial aberrations from measured weights. Avoiding these deviations would improve the accuracy of tPA dosage.

Prehospital Computed Tomography Angiography in Acute Stroke Management

Background: An ambulance equipped with a computed tomography (CT) scanner, a point-of-care laboratory, and telemedicine capabilities (mobile stroke unit [MSU]) has been shown to enable the delivery of thrombolysis to stroke patients directly at the emergency site, thereby significantly decreasing time to treatment. However, work-up in an MSU that includes CT angiography (CTA) may also potentially facilitate triage of patients directly to the appropriate target hospital and specialized treatment, according to their individual vascular pathology. Methods: Our institution manages a program investigating the prehospital management of patients with suspicion of acute stroke. Here, we report a range of scenarios in which prehospital CTA could be relevant in triaging patients to the appropriate target hospital and to the individually required treatment. Results: Prehospital CTA by use of an MSU allowed to detect large vessel occlusion of the middle cerebral artery in one patient with ischemic stroke and occlusion of the basilar artery in another, thereby allowing rational triage to comprehensive stroke centers for immediate intra-arterial treatment. In complementary cases, prehospital imaging not only allowed diagnosis of parenchymal hemorrhage with a spot sign indicating ongoing bleeding in one patient and of subarachnoid hemorrhage in another but also clarified the underlying vascular pathology, which was relevant for subsequent triage decisions. Conclusion: Defining the vascular pathology by CTA directly at the emergency site may be beneficial in triaging patients with various cerebrovascular diseases to the most appropriate target hospital and specialized treatment.

Air-Mobile Stroke Unit for access to stroke treatment in rural regions:

Background In recent years, important progress has been made in effective stroke treatment, however, patients living in rural and remote areas have nil or very limited access to timely reperfusion therapies. Aims Novel systems of care to overcome the detrimental treatment gap for stroke patients living in rural and remote regions need to be developed. Summary of review A possible solution to the treatment disparity between stroke patients living in metropolitan and rural areas may involve the use of specially designed aircrafts equipped with the ability to diagnose and treat acute stroke at remote emergency sites. We describe technical solutions for an Air-Mobile Stroke Unit (Air-MSU) concept, where an aircraft is customized with the ability to perform multimodal computed tomography, in addition to onboard laboratory equipment and telemedicine connection. The Air-MSU is envisioned not only to allow intravenous thrombolysis in the field but also to allow prehospital triage to a comprehensive stroke center through use of contrast intracerebral vascular imaging. Several options for the Air-MSU approach are described, and issues regarding the potential medical benefit, optimal operating environment, technical realization, and integration in pre-existing solutions (e.g., flying doctor service) are addressed. Conclusion The Air-MSU may represent a novel tool to reduce treatment disparity for stroke patients in rural and remote areas. However, this approach requires further implementation research to determine the overall benefit to these communities.