Empirical Study and Modeling of Medical Evacuation System Following a Major Earthquake
|School||Second Military Medical University|
|Course||Social Medicine and Health Management|
|Keywords||medical evacuation MES earthquake Wenchuan earthquake Yushuearthquake system dynamics|
Background:The rescue of life is the primary task of in earthquake rescue. Medical evacuation takes part as one of the main parts of emergency medical rescue, has a direct impact on the treatment effect and prognosis of the sick and wounded. Tremendous progress has been made in response to many medical challenges resulting from earthquakes. However, emergency medical evacuation system (MES) is complicated, and great emphasis should be placed on its organisation to achieve the best results. The research of the structure and effects of the MES in earthquake rescue efforts, form a complex system perspective, becomes a hot topic. However, the current evacuation system, the hierarchical treatment mechanism, the allocation of resources during casualty evacuation, et al, are still based on the theory of wartime casualty medical evacuation; the decision making mostly relied on the experience of the commander. The systemic theoretical guidance and basic research for emergency medical evacuation after major earthquakes were insufficiency. Therefore, as an important part of emergency medical rescue after major earthquakes, carrying out research of the complex adaptive system of MES on its characteristics and regulations, has an important realistic meaning and theoretical significance for improving overall effect of emergency medical rescue after earthquakes.The article is a continuation of Military medical and health research fund project, named of "theoretical research of medical support in military operation other than war"(09MA030), the sub-study of National Key Technologies R&D Program (2009BAI87B05).Objective:With the guidance of the main study idea, this article aimed at developing the related evidence-informed study of earthquake medical rescue. The study is based on (1+n) HDS complex modeling system; combined with the evaluation research of the emergency medical rescue following major earthquakes, as well as the study of health service in military operations other than war, according to the large-scale site investigation, complex adapting system (CAS), modeling technology of Syatem Dynamics (SD), proceeded the therorical study of MES following earthquakes, expanded the mechanism, characteristics and principle of MES, defined the boundary and the structure frame of the MES; carried out the empirical study of MES after Wenchuan earthquake and Yushu earthquake, obtained the structure, agents and evolution regulation of MES. Then built the concept model, logical model and SD model through the analysis of the complexity, problem diagnosis, and modeling process by Vensim software. The behavior rules were stimulated and analogue simulation of system structure and complicated behavior was realized, thus provided a test platform for relevant policy-making.Materials:The first was on-the-spot investigation materials, such as the investigation of military medical rescue operation in Wenchuan and Yushu earthquake, as well as the national emergency medical rescue materials of Yushu earthquake. The investigation forms were various, such as expert interview, small-scale informal meeting, questionnaire. The investigated objects included military mobile health service contingent, field cabin hospital, health prevention team, and field hospital, etc. The author also investigated the State Health Ministry, health department of Qinghai province, and hospitals in Yushu earthquake area. The second was all kinds of documents, reports and daily record. The study group collected more than100documents about emergency medical rescue of Yushu earthquake from the emergency office of the State Health Ministry in2010. More30reports were collected from Gansu, Shaanxi and Tibet Health Department, which record the medical rescue of these provinces in Yushu earthquake rescue. The third was some articles. More than140articles about earthquake emergency medical rescue were retrieved from some database.Methods:Literature, expert interview, field investigation, systematic thinking, complex adaptive system theory, system dynamics modeling method were used in this study. Document review was used to make a definition on the MES in earthquake medical rescue. System thinking and complex adaptive system theory were used to analyze the complexity of the MES in earthquake medical rescue. With the viewpoint of system dynamics modeling, the article established the SD models of MES in earthquake medical rescue. Descriptive analysis and induction were used to make empirical analysis of the MES in Wenchuan and Yushu earthquake medical rescue.Results and Conclusions:The role changing, function expanding, mechanism, characteristics and principle were discussed through the theroricl study. The regulation of agent behavior and the system structure dynamics of MES were obtained by the empirical stydy of Wenchuan and Yushu earthquake. The problem of deficiency in policy experiment method in the field of MES was sloved by the construction of modeling the MES. The optimized system of MES and the policy making target spot of improving the policy making effiency were gained by the simulation of SD model of MES. Finally the policy suggestion were proposed based on the foregoing research.1. The theoretical study of MES after Earthquakes:This study defined the function of health service in military operations other than war, built the theoretical system of medical support in military operations other than war, and explored the medical supporting mechanism innovation in military operations other than war.2. The empirical study of MES from a evidence informed perspective:Field research were carried out to investigate the MES after Wenchuan and Yushu earthquakes. The system structure and operation rule, including the regulation of the occurrence and outcome of the sick and wounded (acquirer of MES), the hierarchy of medical evacuation(structure of MES), medical treatment(regulation of MES), evacuation tools and staffs(supplier of MES) were analyzed based on evidence-informed thinking. The behavioral characteristic, pattern and regulations of agents were discussed.3. The analysis of the complexity of MES. The author analyzed the characteristics such as system structure, operating mechanism, methods of communication from a CAS perspective, explained the complexity of the agent behavior, system structure and interaction of elements, and discussed the complexity of MES after earthquakes. Based on the current situation and system complexity analysis, the author proposed the main problems existing in the MES in earthquake relief were structural barriers of MES institutions resources, behavioral disorders of MES agent, and mechanism obstacles of subsystem coordination.4. The logical Model of MES:The system boundary of MES included the structure of earthquake relief MES, the agents and the external environment of the related systems. The core of the system was the flow of patients in MES. The conceptual model of MES was built then. The logical model of MES was built after the association analysis of agents and the major loops, based on the conceptual model. On the basis of the cause-effect relationship by systemic analysis, the preliminary analysis of the system structure and mechanism of focus question and the qualitative explanation were made for establishing the framework of SD model.5. The constuctiom and simulation of SD model of MES:According to the logical model of MES, the author confirmed the constitution of sub-systems of MES, set up the hypothesis of modeling, analysis the behavior of agents, identified the quantitative cause-effect relationship of elements, draw the flow graph of SD model, set up the main variable and functions, built the SD model of MES and establishing the basis of simulation and intervention experiment. Vensim DSS software was used for building the model, simulation and test.Policy recommendations:The article gave some suggestions to optimize the mechanism, enhance the efficiency of policy making and elevate the whole performance of medical evacuation from the following aspects:Innovation of the system and mechanism of the medical evacuation after earthquakes, improving the continuity of "evacuation" and "treatment" during medical evacuation, strengthening the construction of medical evacuation forces and promote the commanding ability of MES.In this study, the mechanism of medical evacuation of the sick and wounded in earthquake relief efforts was taken as a starting point, the model system as a platform. The author got access to the behavior characteristics of system dynamics and the internal operation mechanism, through simulation study of the system structure, regulation, health policy and external environment changes. In this study, the simulation of MES in earthquake emergency rescue was realized, and a quantitative analysis of simulation tools for the medical evacuation after earthquakes was provided. Based on evidence-informed decision-making, through the empirical analysis of medical evacuation after Wenchuan and Yushu earthquakes, policy recommendations for improving the overall performance of MES were gained.The study made an improvement in the calculating experiment method on the medical evacuation of earthquake rescue, which was the first time in this study field. In the future, the study should gradually enrich the contents of the SD model, so as to the simulating model conform to the real system.