Incorporating real-time citizen responder information to augment EMS logistics operations: A simulation study

Minimizing response time is the key to live-saving missions of emergency medical services (EMS). As an alternative to professional paramedics, citizen responders (CRs), medically trained volunteers in the community, can use their training to help others in their neighborhood or workplace, by rendering emergency responses. Empowered by connected technologies, CRs can be promptly notified by an EMS request upon its arrival, and they may provide time-sensitive (and often life-saving) response before an ambulance arrives. Currently, many EMS agencies, though employing CRs for certain emergency situations, do not necessarily intelligently leverage real-time information of CRs (e.g., position and response propensity) when making decisions on EMS logistic operations (e.g., ambulance dispatch). As a result, opportunities arise for better coordination between CRs and ambulances. In this paper, we investigate the decision problem of dispatching ambulances for priority-differentiated emergencies. We adapt a locally optimal dispatch procedure with incorporation of real-time CR information, which is intended to balance improved response for the current emergency request via dispatching CRs and response preparedness for future requests. We evaluate the adapted dispatch procedure via a discrete event simulation and compare our procedure against the procedure without incorporating CR information and a commonly used dispatch strategy in practice. We perform a sensitivity analysis with respect to the spatial distribution and response propensity levels of CRs. The results suggest that our procedure could lead to substantial and reliable system improvement.