大规模自然灾害下极易产生大量创伤类伤员,对创伤伤员的快速抢救,是灾后救援工作的核心内容。为了实现大规模自然和事故灾难后伤员的快速救治与安置,提高救护车资源的利用率,本文提出了考虑伤员伤情分类的高效伤员救治与转运救援模式,即救护车对轻伤员实施就地救治,对重伤员进行转运医院后急救。根据伤员救治时效理论引入创伤指数计算等待期内轻重伤员的伤情变化,以伤员群体创伤指数之和最小作为优化目标,建立了多车程、需求可拆分的救护车VRP数学模型,并设计了基于车程的邻域搜索的模型快速求解算法,算例仿真和对比研究验证了模型和算法的有效性,给出了大规模自然与事故灾难后伤员分类救治与转运模式下的救护车路径方案。
The rescue of the wounded after the disaster is the core of the post disaster relief work. The number of ambulances compared to the quantity of casualties is obviously insufficient,so the rescue to the wounded is very difficult. However, the severity of the wounded is on the different level. According to "Emergency Time Window" theory, rescuing those who are badly wounded in the first hours after disaster can greatly improve their chance of survival. Beyond the "Emergency Time Window", the badly wounded have less rescuing value than the slightly wounded gradually. In short, the wounded should be classified according to their different characteristics and ambulance resources should be coordinated.
In this context, in order to achieve rapid treatment and placement of the wounded in large-scale disaster, and improve the utilization rate of ambulance resources, the triage treatment and transportation rescue mode, namely taking local treatment to the slightly injury and transporting the badly wounded into hospital by ambulances is proposed. Trauma index is used to calculate the change of the severity of the wounded during the waiting period. The optimization goal is to minimize the trauma index of all wounded, and the Multi-Trip, Split-Demand ambulance VRP mathematical model(MTSD-VRP) is established.
Based on the aboveissues, an approach base-on tabu search algorithm considering vehicle trips is developed for ambulance path optimization. The algorithm uses the "vehicle trip pool" to preserve the trips in better solution and generate new trips, and design the search operator and search strategy based on the trip. The algorithm flow mainly includes the trip generating process, the trip distribution process and the trip refreshing process.
The simulation result shows that the MTSDVRP model and the tabu search algorithm is suitable for ambulance path optimization with wounded classification. The data used in numerical simulation is primarily references to the actual situation of Ya'an City, Sichuan Province. The MTS-DVRP model with wounded classification and the tabu search algorithm based on the vehicle trip can be used as reference for other related studies.
[1] 李运明,顾建文,郑驰,等.芦山地震住院伤员伤情和转运方式调查[J].中国询证医学杂志, 2013,13(12):1397-1400.
[2] Knyazkov K, Oerevitsky I,Mednikov L,et al. Evaluation of dynamic ambulance routing for the transportation of patients with acute coronary syndrome in Saint-Petersburg[J].Procedia Computer Science,2015,66:419-428.
[3] Coppi A, Detti P, Raffaelli J. A planning and routing model for patient transportation in health care[J].Elevtronic Notes in Discrete Mathematics. 2013,41:125-132.
[4] 张玲,陈涛,黄钧,基于最小最大后悔值的应急救灾网络构建鲁棒优化模型与算法[J].中国管理科学,2014,22(7),131-139.
[5] 阮俊虎,王旭坪,杨挺,大规模灾害中基于聚类的医疗物资联合运送优化[J].中国管理科学,2014,22(10),80-89.
[6] 杨文国,黄钧,郭田德.大规模突发事件中伤员救助的救护车分配优化模型[J].系统工程理论与实践,2010,30(7):1218-1223.
[7] 初翔,仲秋雁,曲毅.基于最大幸福原则的多受灾点医疗队支援指派模型[J].系统工程,2015,33(10):149-154.
[8] Mclay L A, Mayorga M E. A model for optimally dispatching ambulances to emergencyalls with classification errors in patient priorities[J]. ⅡE Transactions,2013, 45(1):1-24.
[9] Knightn V A, Harper P R, Smith L.Ambulance allocation for maximal survival with heterogeneous outcome measures[J].Omega,2012,40:918-926.
[10] 袁媛,樊治平,刘洋.突发事件应急救援人员的派遣模型研究[J].中国管理科学,2013,21(2),152-159.
[11] Yi Pengfei, George S K, Paul J A,et al.Hospital capacity planning for disaster emergency management[J]. Socio-Economic Planning Sciences,2010,44(3):151-160.
[12] Ma Guoxuan, Demeulemeester E. A multilevel integrative approach to hospital case mix and capacity planning[J]. Computers & Operations Research.2013,40(9):2198-2207.
[13] Jotshi A, Gong Qiang, Batta R.Dispatching and routing of emergency vehicles in disaster mitigation using data fusion[J]. Socio-Economic Planning Sciences, 2009, 43(1):1-24.
[14] Talarico L, Meisel F, S rensen K. Ambulance routing for disaster response with patient groups[J].Computers & Operations Research,2015,56:120-133.
[15] Andersson T, Värbrand P. Decision support tools for ambulance dispatch and relocation[J].The Journal Operational Research Society,2007,58(2):195-201.
[16] 罗羽,杨雅娜,刘秀娜,等. 重大灾害后大批伤员转运工作的研究现状[J].护理学杂志, 2009,24(2):87-89.
[17] 黄星,袁明,王绍玉.基于Mexican Wv-SVM的震灾人员存活量模型[J].中国管理科学,2016,24(9),140-146.
[18] 何忠杰.论急救的时效性[J]. 中国急救医学,2008,28(7):659-661.
[19] 朱佩芳.损伤严重程度评分的演进[J].中华创伤杂志, 2005, 21(1):36-39.
[20] Cheikh M,Ratli M,Mkaouar O,et al. A variable neighborhood search algorithm for the vehicle routing problem with multiple trips[J].Electronic Notes in Discrete Mathematics,2015,47:277-284.