Dispatch Systems Research Articles

Abstract 18631: Delayed Recognition of Cardiac Arrest in Emergency Medical Dispatch - Best Source of Key Information for System Improvement?

Background: Measuring emergency medical dispatch performance is important for both quality control and clinical outcome. Recognition of cardiac arrest is one of the key metrics when evaluating performance as it is essential for initiation of bystander CPR. It is commonly reported as either recognized or not recognized without any benchmarked definition or time limit. Little is known about the extent of delayed recognition, and if these initial delays lead to clinically relevant delays in CPR. Methods: Prospective, observational study of cardiac arrest calls during a 1 year period in Oslo and Akershus Emergency Services. Dispatch logs, ambulance records and audio files were analyzed. Recognition of cardiac arrest was reported as (1) recognized, (2) not recognized and (3) delayed recognition. Delayed recognition was defined as failure to initially clarify consciousness or abnormal breathing before moving on to further questioning regarding other symptoms or patient history. Calls across all three groups were purposefully selected, and respective dispatchers invited for interviews based on the calls they had experienced. Results: 500 cardiac arrest calls were processed of which 289 calls were included for further analysis as the dispatcher had the opportunity to recognize cardiac arrest and initiate CPR instructions. 74% of cases were recognized, 13% were not recognized and in 13% recognition was delayed. Median time to bystander CPR (first compression performed) was 2,6 (range 0.9,12.3) minutes when cardiac arrest was recognized and 5,1 (range 2.9,9.7) minutes when recognition was delayed. Interviews after calls where cardiac arrest was not recognized or delayed in recognition yielded insight into challenging areas for the dispatchers such as agonal breathing, handling health care workers as callers and non-compliance with protocol that have impacted future training and education. Conclusion: Delayed dispatch recognition of cardiac arrest is common and leads to significant delays in chest compressions. Emergency medical dispatch systems committed to improving cardiac arrest outcomes need to identify and explore all calls that challenge the system, not only those where cardiac arrest is not recognized.

Police ‘empires’ and information technologies: uncovering material and organisational barriers to information sharing in Canadian police services

Information sharing and collaborative policing have become hot topics within policing circles, especially in the wake of such horrific events as school shootings and multiple murder cases. In response to growing concerns over inadequate information sharing and integrated policing, police organisations are actively centralising their services through the implementation of shared technologies (such as computer aided dispatch systems and record management systems). Drawing on interviews and participation observation within two technologically similar Canadian police services, we uncover the material, social and organisational barriers to information sharing and integrated policing. We conclude by arguing that technological anomalies arising from materiality and organisational practices uncovers a critical functional disconnect between the design and patrol officer use of information technologies.

Emergency Medical Dispatch Codes Association with Emergency Department Outcomes

Background. Emergency medical dispatch systems are used to help categorize and prioritize emergency medical services (EMS) resources for requests for assistance. Objective. We examined whether a subset of Medical Priority Dispatch System (MPDS) codes could predict patient outcomes (emergency department [ED] discharge versus hospital admission/ED death). Methods. This retrospective observational cohort study analyzed requests for EMS through a single public safety answering point (PSAP) serving a mixed urban, suburban, and rural community over one year. Probabilistic matching was used to link subjects. Descriptive statistics, 95% confidence intervals (CIs), and logistic regression were calculated for the 107 codes and code groupings (9E vs. 9E1, 9E2, etc.) that were used 50 or more times during the study period. Results. Ninety percent of PSAP records were matched to EMS records and 84% of EMS records were matched to ED data, resulting in 26,846 subjects with complete records. The average age of the cohort was 46.2 years (standard deviation [SD] 24.8); 54% were female. Of the transported patients, 70% were discharged from the ED, with nine dispatch codes demonstrating a 90% or greater predictive power. Three code groupings had more than 60% predictive power for admission/death. Subjects aged 65 years and older were found to be at increased risk for admission/death in 33 dispatch codes (odds ratio [OR] 2.0 [95% confidence interval 1.3–3.0] to 19.6 [5.3–72.6]). Conclusions. A small subset (8% of codes; 7% by call volume) of MPDS codes were associated with greater than 90% predictive ability for ED discharge. Older adults are at increased risk for admission/death in a separate subset of MPDS codes, suggesting that age criteria may be useful to identify higher-acuity patients within the MPDS code. These findings could assist in prehospital/hospital resource management; however, future studies are needed to validate these findings for other EMS systems and to investigate possible strategies for improvements of emergency response systems.

Real –time dispatching modelling for trucks with different capacities in open pit mines / Modelowanie w czasie rzeczywistym przewozów ciężarówek o różnej ładowności w kopalni odkrywkowej

Application of fully automated systems for truck dispatching plays a major role in decreasing the transportation costs which often represent the majority of costs spent on open pit mining. Consequently, the application of a truck dispatching system has become fundamentally important in most of the world’s open pit mines. Recent experiences indicate that by decreasing a truck’s travelling time and the associated waiting time of its associated shovel then due to the application of a truck dispatching system the rate of production will be considerably improved. Computer-based truck dispatching systems using algorithms, advanced and accurate software are examples of these innovations. Developing an algorithm of a computer- based program appropriated to a specific mine’s conditions is considered as one of the most important activities in connection with computer-based dispatching in open pit mines. In this paper the changing trend of programming and dispatching control algorithms and automation conditions will be discussed. Furthermore, since the transportation fleet of most mines use trucks with different capacities, innovative methods, operational optimisation techniques and the best possible methods for developing the required algorithm for real-time dispatching are selected by conducting research on mathematical-based planning methods. Finally, a real-time dispatching model compatible with the requirement of trucks with different capacities is developed by using two techniques of flow networks and integer programming.

Using Advanced Technologies to Manage Airport Taxicab Operations

Airports play a strategic role in economic development of cities and provide connectivity between business and commercial centers. Taxicab operations play a crucial role in determining the overall efficiency of an airport's ground transportation system. However, airport-specific regulations pose challenges for managing taxicab operations effectively. The adoption of emerging technologies for managing taxicabs at airports offers faster, more efficient, and more cost-effective solutions to meet airport regulatory and operational requirements. In this case study, the operation of a central computerized taxicab dispatch system employed at John. F. Kennedy (JFK) International Airport in New York City is evaluated to identify observed limitations and associated avenues for improvement. Based on a review of state-of-practice taxicab dispatch systems deployed in airports worldwide, this research illustrates how modern technologies and procedural changes can be applied to optimize the taxicab operations at JFK and similar airports.

Análise comparativa de metodologias utilizadas no despacho de caminhões em minas a céu aberto

No presente trabalho, realizou-se uma análise comparativa das metodologias utilizadas para o despacho de caminhões em minas a céu aberto. Comparações entre essas metodologias contam com poucos trabalhos publicados na literatura. Metodologias baseadas em programação linear e programação dinâmica e em heurística foram implementadas. Essas metodologias constituem as bases dos algoritmos de alguns dos sistemas de despacho comercializados no Brasil. Foi desenvolvido um modelo de simulação, a fim de se reproduzir o comportamento das operações de lavra de forma a avaliar o impacto das decisões de despacho em cada uma das metodologias estudadas. Os resultados obtidos mostraram o desempenho dos algoritmos, utilizando-se essas metodologias sob diferentes condições em minas a céu aberto. Porém não se pode, através dos resultados obtidos, concluir pela superioridade de uma delas.

Designing Emergency Response Dispatch Systems for Better Dispatcher Performance

Emergency response systems are a relatively new and important area of research in the information systems community. While there is a growing body of literature in this research stream, human-computer interaction (HCI) issues concerning the design of emergency response system interfaces have received limited attention. Emergency responders often work in time pressured situations and depend on fast access to key information. One of the problems studied in HCI research is the design of interfaces to improve user information selection and processing performance. Based on cue-summation theory and research findings on parallel processing, associative processing, and hemispheric differences in information processing, this study proposes that information selection of target information in an emergency response dispatch application can be improved by using supplementary cues. Color-coding and sorting are proposed as relevant cues that can improve processing performance by providing prioritization heuristics. An experimental emergency response dispatch application is developed, and user performance is tested under conditions of varying complexity and time pressure. The results suggest that supplementary cues significantly improve performance, with better results often obtained when both cues are used. Additionally, the use of these cues becomes more beneficial as time pressure and task complexity increase.

Dispatch coordination between high-speed and conventional rail systems

Cross-line trains, as a link between high-speed and conventional rail networks, will increase the complexity of transport organization and lead to significant challenges in dispatch coordination between the two systems. Based on the characteristics of high-speed transport organization, this paper deals with the necessity of dispatch coordination between high-speed and conventional lines from the following two perspectives: the operation of cross-line trains and work coordination in connection stations. An adjustment model for the operation of high-speed trains, taking cross-line trains into account, is established. Finally, the dispatch system is described in terms of construction and process. Methods for organizing dispatch are proposed, and the processes of coordination adjustment under normal and unexpected situations are analyzed. The discussion in this paper may serve as a theoretical basis for the development of high-speed rail dispatch systems.

Commentary: Making a Difference in Emergency Medical Services

Commentary: Making a Difference in Emergency Medical Services

Efficiency and Effectiveness Impacts of a Computer-Assisted Scheduling and Dispatching System Implementation

Computer-assisted scheduling and dispatch (CASD) systems have been implemented in many paratransit systems in the United States to improve the effectiveness and efficiency of operations. This paper contributes to the limited literature of studies documenting the impact of such systems on paratransit operations based on the implementation of such a system in a small city in Illinois. The analysis provides evidence of small but measurable efficiency and effectiveness gains. This paper also provides evidence that proper CASD evaluation efforts should allow enough time after implementation so that not only familiarity with the system has been established, but also most or all of the necessary organizational changes related to the new technology have been completed.

A Collaborative Multiagent Taxi-Dispatch System

This paper presents a novel multiagent approach to automating taxi dispatch that services current bookings in a distributed fashion. The existing system in use by a taxi operator in Singapore and elsewhere, attempts to increase customer satisfaction locally, by sequentially dispatching nearby taxis to service customers. The proposed dispatch system attempts to increase customer satisfaction more globally, by concurrently dispatching multiple taxis to the same number of customers in the same geographical region, and vis-a-vis human driver satisfaction. To realize the system, a multiagent architecture is proposed, populated with software collaborative agents that can actively negotiate on behalf of taxi drivers in groups of size N for available customer bookings. Theoretically, an analysis of the boundary and optimal multiagent taxi-dispatch situations is presented along with a discussion of their implications. Experimentally, the operational efficiency of the existing and proposed dispatch systems was evaluated through computer simulations. The empirical results, obtained for a 1000-strong taxi fleet over a discrete range of N , show that the proposed system can dispatch taxis with reduction in customer waiting and empty taxi cruising times of up to 33.1% and 26.3%, respectively; and up to 41.8% and 41.2% reduction when a simple negotiation speedup heuristic was applied.

Operational Impacts of Wind Generation on California Power Systems

The paper analyzes the impact of integrating wind generation on the regulation and load following requirements of the California Independent System Operator (CAISO). These requirements are simulated and compared for the study cases with and without wind generation impacts included into the study for the years 2006 and 2010. Regulation and load following models were built based on hour-ahead and five-minute ahead load and wind generation forecasts. In 2006, the CAISO system peaked at 50 270 MW. Wind generation (at the installed capacity of 2600 MW) had limited impact on the requirement of load following and regulation in the CAISO Balancing Authority. However, in 2010 (with an expected installed capacity of approximately 6700 MW), this impact will significantly increase. The results provide very useful information for the CAISO to adjust its scheduling and real-time dispatch systems to reliably accommodate future wind generation additions within the CAISO Balancing Authority.

Feasibility of Using Taxi Dispatch System as Probes for Collecting Traffic Information

Using commercial vehicle fleets as probes may be a cost-effective method for obtaining real-time traffic information. Because the taxi dispatch system automatically records the location of a taxi traveling in an urban network, large quantities of real-time travel data can be obtained at low cost. The reliability of this information about real-time traffic conditions, however, has not been investigated. This study examines the feasibility of using taxi dispatch systems as probes for real-time traffic surveillance. The examination focuses on the uncertainties in the data provided by the two types of wireless communications systems—analog and digital Multi Channel Access (MCA)—that are used for dispatching taxis. The study reveals that the digital MCA wireless system is much better than the analog wireless system for data transmission. This article exemplified that selection of longer road segments helps to greatly reduce traffic surveillance errors. Finally, this article discusses the lessons learned from this study and the limitations that must be overcome before the system can be widely deployed.

System of choice

Wide-area measurements have been an integral part of power system operations for over six decades. They have been used in economic dispatch and automatic generation control systems in electric utility control centers using real-time measurements of power flows on remote tie lines and generator output powers. In the late 1960s a new class of wide-area measurement systems came into use--supervisory control and data acquisition (SCADA) systems--in order to provide real-time state estimates of the power system in the electric utility energy management systems (EMSs). Over the years, the "real time" in these SCADA-based measurements came to imply measurements performed over a data window of several seconds without regard to the precise instant when the measurements were made.

Why the Closest Ambulance Cannot be Dispatched in an Urban Emergency Medical Services System

Response time performance is related to increased survival for a relatively small group of patients with critical emergencies. Effectively utilizing current resources is a challenge for all emergency medical services (EMS) systems for reasons of cost-effectiveness and safety. The objective of this study was to identify opportunities for improving ambulance response-time performance in an urban EMS system using fixed deployment. This was a qualitative and quantitative case study which consisted of structured interviews with policy makers, managers, and workers in a fire department EMS division, as well as analysis of dispatch data and observation of dispatch operations. The current computer-aided dispatch (CAD) system does not identify the closest ambulance to the emergency, and therefore, dispatchers must guess which unit is closer when units are not within their stations or "first due" areas. There is no means to track how often dispatchers guess correctly or how often the closest ambulance actually is dispatched to the emergency. Temporal and geographic patterns were identified. Opportunities also were identified to improve response time performance through the use of dynamic deployment and peak-load staffing. The results suggest that there were opportunities for improving ambulance response times by implementing strategies such as peak-load staffing and dynamic deployment. However, the most important improvement would be the implementation of a policy to send the closest ambulance to the emergency. More research is needed to identify how prevalent the failure to send the closest ambulance is within EMS systems that use fixed-deployment response strategies and computer-aided dispatch systems that are incapable of tracking unit locations outside of their stations.

Accuracy of Stroke Recognition by Emergency Medical Dispatchers andParamedics—San Diego Experience

Background. Prehospital personnel in Emergency Medical Service (EMS) systems have varying levels of accuracy in stroke recognition. Identifying the accuracy of emergency medical dispatcher using Medical Priority Dispatch Systems (MPDS) stroke protocol andparamedics may help understand the accuracy of stroke recognition in about 3000 emergency medical dispatch systems andprehospital systems world wide. Objective.Our aim was to assess the accuracy of stroke identification in emergency medical dispatchers (EMD) with high compliance to MPDS protocol andparamedics using Cincinnati Prehospital Stroke Scale (CSS). Methods.This was a retrospective observational study. Data was acquired from a computer assisted dispatch (CAD) system, a computerized paramedic record database anddischarge diagnosis from billing records or stroke registry containing all stroke assessments of patients who presented to the participating study hospitals within 12 hours of symptom onset. We included patients 18 years or older, identified as having stroke by EMD andcity agency paramedics. We excluded patients taken to hospitals not participating in the study, patients with a dispatch determinant of Stroke (card 28) not transported by City EMS agency (SDMSE) to participating hospitals, patients in the stroke registry not transported by SDMSE or patients with no final outcome data. A stroke neurologist or hospital discharge diagnosis of stroke (physician diagnosis) was used to determine the sensitivity andpredictive values of EMD andparamedic recognition of stroke. Results.Of 882 patients with a dispatch determinant of stroke using MPDS Stroke protocol, 367 had a final discharge diagnosis of stroke. This gives a sensitivity of 83% anda positive predictive value of 42% for EMD using MPDS Stroke protocol. Of 477 patients with a paramedic assessment of stroke using CSS, 193 had a final discharge diagnosis of stroke. This gives a sensitivity of 44% anda PPV of 40% for paramedics using CSS. Conclusions.In our EMS system, EMD using MPDS Stroke protocol with a high compliance has a higher sensitivity than paramedics using CSS.

Can Emergency Medical Dispatch Systems Safely Reduce First-Responder Call Volume?

Objectives. Emergency medical dispatch (EMD) protocols are intended to match response resources with patient needs. In a small city that previously sent a first-responder basic life support (BLS) engine company lights-and-siren response to every emergency medical services (EMS) call, regardless of nature or severity, an EMD system was implemented in order to reduce the number of such responses. The study objectives were to determine the effects of the EMD system on first-responder call volume andto assess the safety of the system. Methods. This was a prospective, before–after trial. Using computer-assisted dispatch (CAD) records, all EMS calls in the 120 days before implementation of the EMD protocol andthe 120 days after implementation were identified (excluding a one-month wash-in period). In the “after” phase, patient care reports of a random sample of cases in which an ambulance was dispatched with no first responders was manually reviewed to assess whether there might have been any benefit to first-responder dispatch. Given the lack of accepted clinical criteria for need for first responders, the investigators' clinical judgment was used. Paired t-tests were used to compare groups. Results. There were 9,820 EMS calls in the “before” phase, with 8,278 first-responder engine runs (84.3%), and9,943 EMS calls in the “after” phase, with 3,804 first-responder engine runs (39.1%). The first-responder companies were dispatched to a median of 5.65 runs/day (range 1.1–12.7) in the “before” phase, and3.17 runs/day (range 0.6–5.0) in the “after” phase (p = 0.0008 by paired t-test). Review of 1,816 “after” phase ambulance-only patient care reports (PCRs) found ten (0.55%) in which first-responder dispatch might have been beneficial, but review of EMS andemergency department (ED) records found no adverse outcomes in these ten patients. Conclusions. This study suggests that a formal EMD system can reduce first-responder call volume by roughly one-half. The system appears to be safe for patients, with an undertriage rate of about one-half of one percent.

An Evaluation of the Benefits of Integrating Run-to-Run Control With Scheduling and Dispatching Systems

The benefits of run-to-run control are commonplace and well known: improved process and device performance, increased process tool utilization, improved throughput, reduction of non production (pilot) wafers, etc. Likewise, the benefits of intelligent scheduling and dispatching methods have been shown to reduce cycle time and improve resource utilization. In this paper, we will consider the potential additional benefits that can be obtained through sharing information between a run-to-run control system and a fab dispatch system. Many factors can be taken into consideration when deciding how to dispatch material to process resources-equipment availability, equipment states, time constraints, due dates, bottleneck resources, etc. However, in practice, the decision for lot-to-tool assignment is often based on identifying the highest priority lot and the next available tool. For a process area that has deployed run-to-run control, a number of factors available from the control system can enhance the effectiveness of the dispatch tool. Likewise, the selection of equipment for a given process can affect a controller's efficiency. A controller's state is commonly partitioned by context, such as process tool, product, layer, etc. When this information is used in the dispatch decision, the material can be assigned to a tool with an existing or recently updated partition. The wrong dispatch decision can result in an unnecessary look-ahead run, especially in high-mix environments. This paper will discuss the impact of control-oriented dispatching on factory performance metrics. We describe simulation results where traditional dispatching techniques are compared with a process metrics-based approach, using cycle time and utilization as the key metrics, based on actual production data from a chemical-mechanical planarization process area. We describe a single-resource constrained (process tools only) process and suggest possible enhancements. We illustrate how dispatching can impact batch processes, process cycle time, and controller performance. Practical considerations for integrating these types of systems, such as scalability constraints, will also be discussed.

Effect of Emergency Medical Dispatch Systems on First-Responder Run Volume

Effect of Emergency Medical Dispatch Systems on First-Responder Run Volume

Інформаційно-навігаційні диспетчерські системи класу АVL для управління автоперевезеннями, що використовують супутникові технології

Інформаційно-навігаційні диспетчерські системи класу АVL для управління автоперевезеннями, що використовують супутникові технології