All-advanced life support vs tiered-response ambulance systems*

In this discussion, two principal types of ambulance deployment systems were compared and contrasted: 1) the multipurpose, sole-provider all-advanced life support (all-ALS) ambulance system in which all ambulance-related services (emergent and nonemergent) for a city or region are provided by one fleet of ambulances, each of which is staffed by ALS providers (paramedics); and 2) the tiered ambulance system (tiered) in which some 911 ambulances are staffed by paramedics and others are staffed by basic emergency medical technicians (EMT-Bs) who provide basic life support (BLS) care. When managed with advanced system status management (SSM) techniques, the multipurpose, sole-provider all-ALS ambulance system can significantly reduce response intervals while simultaneously providing both fiscal and operational efficiencies. It can also be used to readily integrate and expand the scope of services for the ambulance provider service, such as interfacility transfers, thus increasing revenues. On the other hand, in large urban centers, the tiered ambulance system can be used to reduce response intervals to critical calls, primarily through the use of sophisticated dispatch triage protocols. This approach requires fewer paramedics in the system and appears, in some systems, to also provide medical care advantages in terms of skills utilization for individual ALS providers as well as a more concentrated focus for medical supervision. Therefore, both of these deployment systems can offer certain advantages depending on local emergency medical services (EMS) system needs as well as the local philosophy of health care delivery. Applicability must therefore be considered in terms of local service demands and other factors that affect the EMS system, including catchment population, statutory and jurisdictional issues, available funding, accessibility of receiving facilities, and medical quality concerns. PREHOSPITAL EMERGENCY CARE 2000;4:1-6