Optimising ambulance logistics for time-critical emergencies

Ambulance services require logistics optimisation to improve patient outcomes in time-critical medical emergencies. Cardiac arrest exemplifies how varied and competing treatment innovations, ranging from drone-delivered defibrillators to on-site heart-lung bypass. These would benefit from being objectively compared in terms of patient coverage, survival probability and system efficiency.

With cooperation from ambulance services nationwide, this project will deploy transport and logistics models to anticipate and design next-generation delivery models for emergency medical services across Australian capital city contexts.

Participants

• iMOVE Australia
• University of Sydney
• NSW Ambulance

Project background

Emergency medical services (EMS) are an essential component of urban healthcare systems targeting time-critical injuries and illnesses. As healthcare techniques and technologies evolve, the way that these services are delivered must evolve alongside them. Logistics is at the core of Ambulance services where vehicles, personnel, equipment and facilities can be optimised to maximise health outcomes.

The traditional model of EMS is to transport the patient to hospital for urgent intervention however, it may be more effective to bring the medical intervention to the patient in some instances, and this decision requires spatial modelling.

Out-of-hospital cardiac arrest (OHCA) is a key motivator for EMS systems globally and the survival rates remain low (12%) with traditional CPR. Using a heart-and-lung bypass machine to stabilise the patient as a bridge to definitive treatment, Extracorporeal Membrane Oxygenation (ECMO) CPR has emerged as a game-changer with survival rates 3-5 times higher than conventional CPR, depending on the speed of the response.

This project builds on previous iMOVE-supported research (Emergency facilities location and transportation routing) that successfully bridged this gap between EMS and logistics by modelling competing logistics strategies for delivering time-critical ECMO CPR in Sydney.

Critical areas for further research

Building on this success, discussions with ambulance services across Australia have identified two critical areas for further research.

1. Suitability for other Australian locations

While the Sydney study provided a robust, locally-optimised recommendation, it is unknown how sensitive this optimal strategy is to different urban geographies, population distributions, road networks, and existing hospital configurations found in other Australian capital cities. Ambulance services in other states, currently offering or considering ECMO CPR, require this tailored analysis.

Looking beyond Sydney, the larger capital cities (Melbourne, Adelaide, Brisbane and Perth) are actively evaluating or designing their ECMO CPR services, so their status quo and test scenarios will be tested. Darwin, Canberra and Hobart will be addressed more hypothetically as their OHCA ECMO CPR systems are still developing. Cumulative evidence from these cities can be used in meta-analysis to evaluate the generalisability of the findings.

2. Optimal integration of air-based assets

Many ambulance services operate in conjunction with aeromedical services (e.g., helicopters). There is a pressing need to understand how these air-based assets can be optimally integrated into OHCA response, particularly for delivering emerging technologies like drone-delivered defibrillators (AEDs) or facilitating rapid ECMO CPR team deployment via helicopter.

A major question around expanding to aeromedical responses is the cost, so this extension requires economic evaluation as well as spatial modelling. Some international services are already trialling helicopter-based ECMO CPR without comprehensive spatial modelling to guide deployment.

Similarly, NSW Ambulance is exploring drone-delivered defibrillators, and this project will provide the evidence base to determine optimal device numbers, locations, and expected population coverage.

Project objectives

This project has two primary objectives:

1. Extend the spatial modelling of optimal ECMO CPR delivery strategies to all Australian capital cities. i.e. to assess how the recommended strategy and the resulting expected survival probabilities vary with diverse geographies, demographics, and health systems, providing actionable insights for ambulance services nationwide.
2. Integrate aeromedical services into cardiac arrest response models. This includes evaluating the potential survival benefits and logistical implications of drone-delivered defibrillators (AEDs) and helicopter-facilitated ECMO CPR, aiming to move advanced cardiac arrest technologies to patients faster and more efficiently.

Please note …

This page will be a living record of this project. As it matures, hits milestones, etc., we’ll continue to add information, links, images, interviews and more. Watch this space!