Abstract
In life-threatening emergency situations in which every second counts, the timely arrival of an ambulance can make the difference between survival and death. In practice, the response-time targets, defined as the maximum time between the moment an incoming emergency call is received the moment when onsite medical aid is provided, are often not met. A promising means to reduce late arrivals by ambulances is to proactively relocate ambulances to ensure good coverage by the available ambulances in real time. This paper evaluates two dynamic relocation policies that an ambulance service provider in the Netherlands modified for operational use and implemented in a software tool for realtime decision support. The policies were used in a pilot program within a dispatch center for 12 weeks. Based on the success of this pilot, our policies were adopted for ongoing use and permanent implementation. This paper describes the relocation methods, evaluates the pilot, provides statistics for efficiency improvements, and discusses the experiences of ambulance dispatchers and management.
Ambulance service providers (ASPs) worldwide must implement policies to improve efficiency, such as budget cuts or performance improvement programs. They can obtain efficiencies via changes to medical equipment, staff training, and the logistic domain. In this paper, we focus on the latter. The goal is to allocate the “right resources at the right time at the right place,” such that the probability of meeting their response-time targets, within given budget constraints, is optimized.
Conclusion
In this study, we put two dynamic ambulance-management policies into practice at an EMS dispatch center in Flevoland, an ambulance region in the Netherlands. We observed that the effectiveness of relocations improved when using a dynamic relocation policy, compared to previous years in which relocation algorithms were not used. One advantage we perceived is less latency, that is, the number of service calls for which the response time exceeds the threshold set, for a similar demand volume and number of relocations. The EMS region met the response-time requirement of 95 percent within 15 minutes for the first time in its history in 2015. The results indicate that both DAM policies perform comparably.
