About AACN

Is Your EMS System Using AACN Crash Data?

Is your EMS system currently using or aware of the Advanced Automatic Collision Notification (AACN) crash data that is available and being shared by many of the automakers through their various Telematics Service Providers (TSP’s) directly to 9-1-1 Public Safety Answering Point (PSAP) personnel? AACN, and its early version Automatic Collision Notification (ACN), have been available and in use for several years but many people are still now fully aware of its potential. These systems provide important information immediately after a crash that be used in selecting the appropriate EMS response and early destination decisions for the patient.

You may know the TSP’s through their brand names such as GM’s OnStar, Ford 911 Assist, or one of the auto brands that use the Sirius XM Connected Vehicle Services programs. The type of information the TSP’s provides the PSAP will vary greatly among the various providers as there is not yet a standard for what data is sent. The information can be as basic as notification that an air bag has deployed indicating a crash and the GPS coordinates for the location with the make and model of the vehicle involved. More advanced systems can now transmit critical data such as Delta V (change in velocity on impact), principal direction of force, crash with multiple impacts, and vehicle rollover. Through direct communication with the occupant or information relayed by the TSP provider you can obtain vital information like the number of patients, number of vehicles involved, and other occupant injury information. And this is all available even as the first units are responding. An advanced feature that some TSP’s provide is the Injury Severity Score (ISS) score. The ISS is determined from vehicle crash data and an injury severity prediction (ISP) algorithm to determine a prediction of the possibility of severe injury. The National Expert Panel for Field Triage which was comprised of emergency medicine physicians, trauma surgeons, automotive engineers, and EMS personnel established a 20% risk of ISS of >15 as the threshold for urgent transport to a trauma center. Most TSP’s will only provide information that the crash has a high probability of severe injury and not the actual ISS number to avoid unnecessary confusion regarding the ISS number scale.

So how could you use this information in your system? A basic use is the single car crash where no one witnessed the incident and the driver is unable to communicate or call for help. The vehicles telematics system will notify the TSP provider of the crash and give the GPS coordinates. Other more advanced uses would include using the ISS index of a high probability of severe injuries to the vehicles occupants to dispatch an ALS unit instead of only a BLS unit in a two-tiered system. The responding EMS crews could use this information in determining the patient transport destination like immediately transportation to a trauma center per the Field Triage Decision Scheme which now includes “vehicle telemetry data consistent with high risk of injury” as a factor, see decision scheme below. Another easy way to integrate the vehicle telemetry data in to your response is to use the Emergency Medical Dispatch (EMD) protocol software/cards for calls where vehicle telematics data is available. Most of the EMD dispatch system vendors have already added this feature so it might be just sitting there waiting in your system to be utilized.

Advanced Automatic Collision Notification (AACN) Education for EMS and 911 Medical Directors

NAEMSPThe Advanced Automatic Collision Notification (AACN) project is a joint venture managed by the American College of Emergency Physicians (ACEP) and the National Association of EMS Physicians (NAEMSP) and funded by the National Highway Traffic Safety Administration (NHTSA). The two-year project will develop and disseminate online educational training for EMS and 911 Medical Directors and other EMS stakeholders on the benefits of using AACN data to assist in improving patient outcomes for victims of motor vehicle crashes.

ACEPThe training course content will be based on information from several sources including “Recommendations from the Expert Panel: Advanced Automatic Collision Notification and Triage of the Injured Patient” and “Advanced Automatic Collision Notification: A Comprehensive Education Strategy for Medical Directors.” The Principal Investigator for the project is Scott Sasser, MD, FACEP who assisted in the development of the Recommendations from the Expert Panel document and the lead subject matter expert is Stewart Wang, MD, PhD, FACS, from the University of Michigan who has conducted research on AACN for years and developed a number of related training programs.

AACN data can provide information to improve care for injured crash victims. Timely crash notifications can reduce response times. AACN data can be used to predict the likelihood of a serious injury in a crash. This information can be used to improve triage decision-making and EMS resource utilization, resulting in shorter times to definitive trauma care.

The training program will include information on the biomechanics of crash injuries and how crash data are used to predict injury severity. After a crash, electronic data transmitted via AACN can be to inform EMS dispatch and triage decisions. Recommendations from the expert panel* say that in the event of a crash, the following electronic information should be transmitted by the vehicle to the AACN providers: Delta V, principal direction of force (PDOF), seatbelt usage/or without, crash with multiple impacts and vehicle type.

Stakeholder organizations invited to participate in the project include EMS physician medicals, 911 and emergency dispatch, EMS providers and educators, and state EMS officials.

Contact us for more information.

*A full list of names for the expert panel can be found in “Appendix B” in the Recommendations from the Expert Panel: Advanced Automatic Collision Notification and Triage of the Injured Patient listed under Documents on the Resources page of this site.


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