Acute ischemic stroke (AIS) is a major cause of death and disability in the United States. With advancements in therapeutic reperfusion, it has become clear that improving time-to-treatment is among the most important factors in yielding better outcomes for patients. When AIS occurs in the community, away from readily available interventions, timely recognition and transport are paramount to decreasing the time-to-treatment and ultimately increasing rates of reperfusion and reducing morbidity and mortality. Over the past several years, investigations have launched studying the efficacy of mobile stroke units (MSU) in reducing the morbidity and mortality burden of AIS. MSUs are specially designed transport vehicles, run by trained expert stroke management personnel, and stocked with diagnostic imaging equipment in the form of computed tomography scanners and fibrinolytic therapy. In a number of prospective study designs comparing MSUs to standard management by emergency medical services, researchers have utilized several endpoints including time-to-treatment, rates of symptom resolution, and long-term recovery from AIS. These studies have generally demonstrated better outcomes with MSUs and provided evidence for the efficacy of the MSU model in treating AIS. However, most studies have been limited to metropolitan regions of the country, and no randomized-controlled trials have been completed, although one is currently underway. There is little evidence, however, evaluating the cost-effectiveness of MSUs in the management of AIS. The expense of constructing and operating these specialized vehicles over ten years has been estimated to be millions of dollars, while the cost of a single case of AIS can range anywhere from the cost of the emergency department visit to the inclusion of long-term care from resultant sequelae depending on the patient outcome. It remains unclear to what degree the upfront investment in quicker management for AIS is capable of producing downstream cost savings for the healthcare system in the setting of demonstrated improved outcomes. In this study, I propose a method of cost-effectiveness analysis to compare the MSU model to standard management of AIS occurring in metropolitan communities to determine whether MSUs are cost-effective, or possibly cost-saving.

Stroke är den näst vanligaste dödsorsaken i världen och den tredje vanligaste orsaken till funktionshinder. I Sverige drabbas cirka 25 000 personer årligen. Patienter med stroke är den enskilda sjukdomsgrupp som står för flest vårddagar på svenska sjukhus. I akut behandling av stroke används termen ”Time is Brain”, då det dör cirka två miljoner hjärnceller vid varje minuts fördröjning. Det har utförts stora ansträngningar i två decennier för att effektivisera akuta vårdkedjan vid stroke. Endast två till 13 procent av patienterna får möjlighet till behandling på sjukhus med trombolys och antalet trombektomi är mycket lägre. Av de patienter som får trombolys är det cirka en till tio procent som får trombolys inom en timme efter symtomdebut. Främsta orsaken till underbehandling är att patienter inte når sjukhuset tillräckligt snabbt för att undersökas och behandlas inom det smala terapeutiska fönstret. I Sverige år 2016 anlände 33 procent av patienterna med stroke inom tre timmar till sjukhus och antalet har inte ökat sedan 2011. Det var angeläget att beskriva befintlig kunskap om hur ambulanspersonal kan påskynda behandlingen för patienter med stroke. Syftet var att belysa ambulansteamets betydelse för att minska tiden från symtomdebut till behandling av stroke Metoden för studien var en litteraturöversikt med 16 vetenskapliga artiklar publicerade mellan åren 2012 och 2017. Artiklarna söktes i databaserna PubMed och Cinahl. Resultatet som framkom av de valda artiklarna kunde sammanställas genom två huvudkategorier och fem underkategorier. Den ena huvudkategorin handlade om ambulanspersonalens omhändertagande av patienter med stroke. Den andra huvudkategorin handlade om ambulanspersonalens kunskap. Resultatet visade att ambulanspersonal kunde genom teamarbete i ett ambulansfordon med en inbyggd röntgenapparat, kallad Mobile Stroke Unit (MSU), förkorta tiden från symtomdebut till behandling. MSU var mellan 25 till 81 minuter snabbare, jämfört med konventionell ambulans. Dörr-till-nål tiderna (tiden från det att patient ankommer till sjukhus till start av trombolys) förbättrades med fem minuter när ambulanspersonal förvarnade sjukhusen med strokelarm. Ambulanspersonal förbättrade inte akuta vårdkedjan med hjälp av telemedicin. Patienter med stroke i bakre cirkulationen hade en timmes prehospitala fördröjningar jämfört med patienter med stroke i främre cirkulationen. Akuta vårdkedjan förbättrades inte när ambulanspersonal fick en timmes föreläsning om stroke. Slutsatsen var att ambulansteamet förkortade tiden från symtomdebut till behandling genom teamarbete i Mobile Stroke Unit. Ambulansteamet förbättrade inte akuta vårdkedjan med hjälp av telemedicin. Det skedde prehospitala fördröjningar för patienter med stroke i bakre cirkulationen. Ytterligare forskning av MSU behövs. Framtida randomiserade studier bör undersöka kliniskt utfall och kostnadseffektivitet. Det bör även forskas i området om hur ambulansteamet kan minska tiden från symtomdebut till behandling av stroke i en konventionell ambulans. Nyckelord: stroke, ambulanspersonal, tid, prehospital trombolys, Mobile Stroke Unit. / Stroke is the second most common cause of death in the world and the third most common reason cause for disability. In Sweden approximately 25000 people are affected annually. Patients whit stroke are the group that accounts for most care days in Swedish hospitals. In acute stroke treatment, the term "Time is Brain" is used, as about two million brain cells die at every minute delay. Despite two decades of substantial efforts to streamline systems of care in stroke, only two to 13 percent of patients receive the treatment thtombolysis in a hospital and the rates of delivery of thrombectomy are far lower. Of the patients who are treated with thrombolysis, approximately one to ten percent receives thrombolysis within one hour after symptom on set. The main reason for such undertreatment is that patients do not reach the hospital quickly enough to be assesed and treated within the narrow therapeutic window. In Sweden 2016, only 33 percent of patients with stroke arrived to the hospital within three-hours after symptom on set and the rates has not increased since 2011. It was important to describe existing knowledge about how the ambulance staff can shorten the time from symptom on set to treatment for stroke patients. The aim was to highlight the importance of the ambulance staff to reduce the time from symptom on set to stroke treatment. The method of the study was a literature review of 16 scientific articles published between the years 2012 and 2017. The articles were searched in the PubMed and Cinahl databases. The results obtained from the selected articles were compiled by two main categories and five subcategories. One main category was about the care of ambulance staff in patients with stroke. The second main category was about the ambulance staff's knowledge. The result showed that ambulance staff can shorten the time from symptom on set to treatment though teamwork in an ambulance with an inbuilt CT-scan, called Mobile Stroke Unit (MSU). MSU was between 25 minutes and 81 minutes faster, compared to conventional ambulance. Door-to-Needle time (time from patient arriving to hospital until start of thrombolysis) improved with five minutes when ambulance staff warned the hospital with a strokealarm. Ambulance staff did not improve the system of care using telemedicine. Patients with stroke in the posterior circulation had one hour of prehospital delays compared with patients with stroke in the anterior circulation. The system of care did not improve when ambulance staff received an hour's lecture on stroke. The conclusion was that ambulance staff shortened the time from symptom on set to treatment through teamwork in the Mobile Stroke Unit. Ambulance staff did not improve the system of care using telemedicine. There where prehospital delays for patients with stroke in the posterior circulation. Further research of MSU is required. Further randomized studies should investigate clinical outcome and cost-effectiveness. It should also be researched in the area of how the ambulance staff can shorten the time from symptom on set to treatment in a conventional ambulance Keywords: stroke, emergency medical service, time, prehospital thrombolysis, Mobile Stroke Unit.

No description available.

Immediate treatment is of extreme importance for stroke patients. However, providing fast enough treatment for stroke patients is far from trivial, mainly due to logistical challenges and difficulties in diagnosing the correct stroke type. One way to reduce the time to treatment is to use so-called Mobile Stroke Units (MSUs), which allows to diagnose and provide treatment for stroke patients already at the patient scene. A well-designed stroke transport policy is vital to improve the access to treatment for stroke patients. Simulation and mathematical optimization are useful approaches for assessing and optimizing stroke transport policies, without endangering the health of the patients. The main purpose of this thesis is to contribute to improving the situation for stroke patients and to reducing the social impacts of stroke. The aim is to study how to use simulation and optimization to achieve improved analysis and planning of prehospital stroke care. In particular, we focus on assessing the potential use of MSUs in a geographic area. In this thesis, optimization is used to identify the optimal locations of MSUs, and simulation is used to assess different stroke transport policies, including MSU locations. The results of this thesis aim to support public health authorities when making decisions in the prehospital stroke care domain. In order to fulfill the aim of this thesis, we develop and analyze a number of different simulation and optimization models. First, we propose a macro-level simulation model, an average time to treatment estimation model, used to estimate the expected time to treatment for different parts of a geographic region. Using the proposed model, we generate two different MSU scenarios to explore the potential benefits of employing MSUs in Sweden’s southern healthcare region (SHR).   Second, we present an optimization model to identify the best placement of MSUs while making a trade-off between the efficiency and equity perspectives, providing maximum population coverage and equal service for all patients, respectively. The trade-off function used in the model makes use of the concepts of weighted average time to treatment to model efficiency and the time difference between the expected time to treatment for different geographical areas to model equity. In a scenario study applied in the SHR, we evaluate our optimization model by comparing the current situation with three MSU scenarios, including 1, 2, and 3 MSUs. Third, we present a micro-level discrete event simulation model to assess stroke transport policies, including MSUs, allowing us to model the behaviors of individual entities, such as patients and emergency vehicles, over time. We generate a synthetic set of stroke patients using a Poisson distribution, used as input in a scenario study. Finally, we present a modeling framework with reusable components, which aims to facilitate the construction of discrete event simulation models in the emergency medical services domain. The framework consists of a number of generic activities, which can be used to represent healthcare chains modeled in the form of flowcharts. As the framework includes activities and policies modeled on the general level, the framework can be used to create models only by providing input data and a care chain specification. We evaluate the framework by using it to build a model for simulating EMS activities related to the complex case of acute stroke. / <p>Note: The papers are not included in the fulltext online.</p>

Tid till behandling är livsviktigt för människor som får en stroke. På olika platser i världen har man därför sett värdet i att införskaffa en specialambulans för stroke (stroke-ambulans) som har specialutrustning och specialpersonal som kan utföra intravenös behandling (trombolys). Då det är uppenbart att dess involvering i vården skulle hjälpa åtminstone en viss andel patienter används ofta ingen utvecklad metod eller analys av var och hur denna stroke-ambulans ska placeras. Genom att noggrant undersöka läget i Skåne län om hur denna placeringen kan gå till, är vårt mål att genom vår metod, som bygger på optimering av förväntade transporttider, upplysa beslutstagare om olika perspektiv man bör ta hänsyn till. Vår metod kan användas över olika geografiska områden.Vi föreslår en optimeringsmetod som utgår från två olika perspektiv: effektivitet och jämlikhet. Metoden visar att beroende på vilket perspektiv man väljer, kan den optimala placeringen för ett givet område variera kraftigt. Det är därför viktigt att beslutstagare av placering för stroke-ambulanser har tydliga och väl genomtänkta mål. Dessa mål bör även innefatta de lokala sjukhusens mål när det kommer till förbättring av behandlingstiden för strokepatienter, s.k. door-to-needle-time (DTN) då dessa i vissa fall kan göra större förbättringar än vad en införskaffning av en stroke-ambulans skulle göra. / Tid till behandling är livsviktigt för människor som får en stroke. På olika platser i världen har man därför sett värdet i att införskaffa en specialambulans för stroke (stroke-ambulans) som har specialutrustning och specialpersonal som kan utföra intravenös behandling (trombolys). Då det är uppenbart att dess involvering i vården skulle hjälpa åtminstone en viss andel patienter används ofta ingen utvecklad metod eller analys av var och hur denna stroke-ambulans ska placeras. Genom att noggrant undersöka läget i Skåne län om hur denna placeringen kan gå till, är vårt mål att genom vår metod, som bygger på optimering av förväntade transporttider, upplysa beslutstagare om olika perspektiv man bör ta hänsyn till. Vår metod kan användas över olika geografiska områden.Vi föreslår en optimeringsmetod som utgår från två olika perspektiv: effektivitet och jämlikhet. Metoden visar att beroende på vilket perspektiv man väljer, kan den optimala placeringen för ett givet område variera kraftigt. Det är därför viktigt att beslutstagare av placering för stroke-ambulanser har tydliga och väl genomtänkta mål. Dessa mål bör även innefatta de lokala sjukhusens mål när det kommer till förbättring av behandlingstiden för strokepatienter, s.k. door-to-needle-time (DTN) då dessa i vissa fall kan göra större förbättringar än vad en införskaffning av en stroke-ambulans skulle göra. / The time to treatment is vital for people who suffer from a stroke. Therefore, in different places in the world, the value of acquiring a specially developed ambulance for a stroke (i.e., a Mobile Stroke Unit, MSU) with special equipment and specialists who can perform intravenous treatment (thrombolysis) has been identified. Since it is clear that an MSU’s involvement in health care would aid at least a certain proportion of the patients, the MSU is often purchased and placed without any developed method or analysis of where and how this MSU is to be placed. By carefully examining the situation in Skåne Municipality of how this placement could be performed, we will inform decision makers about different perspectives that should be taken into consideration, including other areas than Skåne.Our optimization method showed that depending on what perspective you are investing, efficiency or equality, the optimal placement for any given area can vary greatly. It is therefore importantthat decision-makersofMSUpurchaseshaveclearandwell-thought-outgoals.These goals should also include the goals of the local hospitals when it comes to improving the treatment time for stroke patients, door-to-needle (DTN), as the DTN may in some cases make greater improvements than a purchase of an MSU would. / The time to treatment is vital for people who suffer from a stroke. Therefore, in different places in the world, the value of acquiring a specially developed ambulance for a stroke (i.e., a Mobile Stroke Unit, MSU) with special equipment and specialists who can perform intravenous treatment (thrombolysis) has been identified. Since it is clear that an MSU’s involvement in health care would aid at least a certain proportion of the patients, the MSU is often purchased and placed without any developed method or analysis of where and how this MSU is to be placed. By carefully examining the situation in Skåne Municipality of how this placement could be performed, we will inform decision makers about different perspectives that should be taken into consideration, including other areas than Skåne.Our optimization method showed that depending on what perspective you are investing, efficiency or equality, the optimal placement for any given area can vary greatly. It is therefore importantthat decision-makersofMSUpurchaseshaveclearandwell-thought-outgoals.These goals should also include the goals of the local hospitals when it comes to improving the treatment time for stroke patients, door-to-needle (DTN), as the DTN may in some cases make greater improvements than a purchase of an MSU would.

No description available.

When suffering a stroke, the time to treatment is one of the key factors to increase the chance of desirable recovery. To ensure proper treatment, a diagnosis has to be made before treatment can begin. The potential consequences of treating a misdiagnosis can be severely harmful or even deadly. A Mobile Stroke Unit (MSU) is an ambulance equipped with the necessary tools to diagnose and begin treatment of stroke before reaching a hospital, reducing the time to initial treatment. We contribute a model to identify suitable locations of MSUs within a geographical region. We propose a Multi-State Particle Swarm Optimization (MBPSO) algorithm variation to solve this problem. Furthermore, we demonstrate the use of the model in a scenario created in the Southern Healthcare Region of Sweden in order to properly communicate and evaluate the model. The objective of our MBPSO variation is to find locations within a geographical region which are suitable for placing MSUs. The results of the solution shows that populations previously not covered by stroke care within one hour of an emergency call has the potential to be covered up to 81%.