Cleared for Takeoff: An Overview of Helicopter EMS
“Currently, in the United States, there are approximately 1,000 HEMS helicopters serving an estimated 400,000 patients annually…”
In the realm of pre-hospital medical care, various modes of transportation exist within emergency medical services (EMS) agencies. Helicopter emergency medical services (HEMS) is a relatively new form of transportation where patients are transported via medically equipped helicopters. In this blog post, we will review the background of HEMS systems, which patients are better suited for air versus ground transport, and what the footprint of HEMS is in New England.
The first reports of vertical flight start as early as 400 AD with Chinese kites utilizing a rotary wing as a source of lift. However, the development of the modern-day helicopter is credited to a man named Igor Sikorsky in the beginning of the 20th century (Figure 1). [1] Since then, helicopters went on to serve medical transportation for military purposes before entering the civilian world after the Vietnam War. In fact, the first civilian medical helicopter transport began in 1972 at St. Anthony’s Hospital in Colorado. [2]
Figure 1: Early helicopter models1
Since then, HEMS systems have taken off. Currently, in the United States, there are approximately 1,000 HEMS helicopters serving an estimated 400,000 patients annually. [3,4] HEMS is mainly utilized for interfacility transfer, but these programs may also participate in direct scene transport, organ procurement, or search and rescue missions. [4] These programs are staffed by pilots, nurses, paramedics, physicians, respiratory therapists, anesthetists, amongst others. [4,5] While there is no standardized HEMS crew, most HEMS generally operate with a nurse, paramedic, and pilot. However, the makeup may change depending on the specific requirements of the call or the geographic location. [4] For instance, agencies in Europe are more likely to utilize physicians during transport. Regardless of flying status, physicians in the United States can serve in other roles such as protocol development, education, and medical direction. [4]
HEMS programs are well-established in today’s day and age, but the decision of whether to utilize air versus ground transport requires a fundamental understanding of the pros and cons of each. Most notably, helicopters are faster and can reach settings that may be less accessible to ground transportation. Helicopters are not limited by roads or traffic. However, they are significantly more expensive to operate and maintain, significantly limited by weather, and more dangerous to operate compared to their counterparts. For instance, in the setting of an accident, helicopters pose a 34% fatality rate compared to <1% in ambulance accidents. [5]
As such, the decision to activate a HEMS system requires careful consideration of the risks and benefits of HEMS transportation versus ground transportation. Assuming that the weather is safe for helicopter transport, the decision to deploy air transport brings into question various factors. [6] For instance, how important is it clinically for the patient to minimize transport time? Is there the right infrastructure at the sending hospital/scene and the receiving hospital to land a helicopter? Will the patient and all the required equipment for transportation fall within the size and weight limitations of the helicopter? Clinically, the National Association of EMS Physicians (NAEMSP) has guidelines, which are summarized in Table 1, though individual HEMS protocols may differ. [6]
Table 1: Common traumatic and medical considerations for HEMS activation.6
HEMS systems are particularly advantageous in rural settings as they extend the level of care in the region, minimize transport times, and make direct transport available to specialized centers. [7] Within the United States, New England is a unique area for HEMS systems as there are many specialized tertiary centers in urban areas (Providence, Boston, Portland to name a few). However, there are also many rural parts with limited access to healthcare and would require long ground transport times (Vermont, New Hampshire, upstate New York, etc.). Currently, there are several HEMS systems including Boston MedFlight, LifeFlight of Maine, Life Flight of UMass, Life Star in Connecticut, amongst others.
Many helicopter systems are based in a single state but provide coverage to neighboring states. Rhode Island is unique in the sense that it does not have its own HEMS program. This is because the general threshold to activate a helicopter over ground transport is 45 minutes of ground travel time from a tertiary center. In Rhode Island, much of the state is accessible by ground within that time frame. As a result, while neighboring HEMS systems are available, Rhode Island does not have its own HEMS program.
In summary, HEMS provide a unique form of medical transport. While there are many advantages to utilizing HEMS over ground transport, there are other considerations when deciding when to deploy one mode of transport over the other. Since the first HEMS systems in the United States started in the 1970s, HEMS is becoming increasingly popular and an option that most Americans have access to.
Key Take-Aways
HEMS increases access to healthcare and provides faster transport times compared to ground transport
HEMS is inherently more dangerous, and there are other factors to consider when flying such as weather or available helicopter infrastructure
Certain patients benefit from HEMS over ground transport, and HEMS is now widely available in the United States
Rhode Island does not have its own HEMS system, but neighboring programs provide HEMS access to and from Rhode Island
Author: Prassana Kumar, MD, is a third-year emergency medicine resident at Brown Emergency Medicine Residency.
Faculty Reviewer:
Ken Williams, MD is an attending emergency medicine physician at Rhode Island Hospital and Newport Hospital.
Elizabeth Kadow, MD is an attending emergency medicine physician at Rhode Island Hospital and Newport Hospital.
References
1. Boyne, Walter James. "helicopter". Encyclopedia Britannica, 31 May. 2024, https://www.britannica.com/technology/helicopter. Accessed 8 June 2024.
2. Thomas F. The development of the nation's oldest operating civilian hospital-sponsored aeromedical helicopter service. Aviat Space Environ Med. 1988;59(6):567-570.
3. A history of helicopter emergency medical services. Airbus. September 1, 2021. Accessed 8 June 2024. https://www.airbus.com/en/newsroom/stories/2020-12-a-history-of-helicopter-emergency-medical-services.
4. Imoehl J, Steuerwald MT, Cathers AD. A Model Curriculum for a Helicopter Emergency Medicine Services (HEMS) Rotation for Resident Physicians. J Educ Teach Emerg Med. 2020;5(3):C82-C132. Published 2020 Jul 15. doi:10.21980/J8GP97
5. Steenhoff TC, Siddiqui DI, Zohn SF. EMS Air Medical Transport. In: StatPearls. Treasure Island (FL): StatPearls Publishing; June 26, 2023.
6. Godfrey A, Loyd JW. EMS Helicopter Activation. In: StatPearls. Treasure Island (FL): StatPearls Publishing; September 26, 2022.
7. Thomas SH, Arthur AO. Helicopter EMS: Research Endpoints and Potential Benefits. Emerg Med Int. 2012;2012:698562. doi:10.1155/2012/698562