Criteria for Consideration of Air Versus Ground Transport

Time and Distance Indicators

Distance. Distance to the closest appropriate facility is too great for safe and timely transport by ground ambulance.

Transport Time. The patient's clinical condition requires that the time spent out of the hospital environment, in transport, be as short as possible.

Timely Treatment. The patient requires a specific treatment or timely treat­ment that is not available at the referring facility (or scene) to minimize morbidity and mortality.

Transport Delays. The potential for transport delay that may be associ­ated with the use of ground or air transport (eg, weather or weather-related obstacles, traffic congestion, construction, road obstacles, location of patient, and distance) is likely to worsen the patient's clinical condition.

Logistic Indicators

Critical Care. The patient requires critical care support (eg, monitoring, personnel, medication, special equipment) during transport that is not available from the local ambulance service.

Inaccessible Area. The patient is located in an area that is inaccessible to regular ground traffic, impeding ambulance egress or access to the scene because of environmental obstacles or conditions, weather-related events (eg, floods, heavy snowfall), traffic congestion, wilderness rescue, or other geographic considerations.

Local Ground Resources. The use of a local ground transport service would leave the local area without adequate emergency medical service coverage, or local ground units are not trained or available for long-distance neonatal- pediatric transport.

Transport Times

When evaluating the time needed to undertake and complete a transport, many factors are involved beyond the speed of the vehicle and the distance between the referring and receiving facilities. The time-related considerations for transport include the following:

Mode of Transport

To keep the out-of-hospital time to a minimum, consideration must be given to the distance between the referring and receiving hospitals.

Response Time

The length of time from receipt of a transport call until the transport team arrives at the referring facility or scene of an accident often is referred to as the response time. Transport services that respond directly to the scene clearly require a rapid response time. Similarly, in a true medical emergency, if a transferring facility cannot stabilize a patient's condition, the response time to the referring facility with a critical care transport team may be more crucial than the time in transit to the receiving facility after the patient's condition has been stabilized. Many variables enter into the response time equation. Following the initial contact, there is the time needed to accept the patient and to mobilize and dispatch the transport team. Dedicated ground and helicopter teams can often be on their way within 15 minutes, although specific guidelines and requirements may vary between programs and municipalities, as well as with specific patient populations (eg, scene response teams that depart in ≤5 minutes). The departure of a medical air­plane usually takes longer, ranging from 30 minutes to an hour or more. The fixed-wing delay often is because the transport team and pilot may be on call rather than on-site at the airport. In addition, the pilot is required to preflight the aircraft, complete a weight and balance, and file a flight plan before departure.

The various response times and related logistics of the vehicle options may make the choice more difficult. A ground ambulance may be available immediately at a referring facility that could be en route to the receiving facility long before a distant helicopter could arrive at the referring facility. The ground ambulance, however, may have to contend with local terrain, traffic, construction, and other ground-related delays, and the local emer­gency medical services (EMS) team may not have the training, experience, or equipment required to manage the patient in transit.

If a helicopter is to be considered, the response time should include the availability of a safe and close helipad or landing zone. An on-site helipad or landing area near both facilities is advantageous. A distant landing zone that would require a 3-point transfer (an intermediary transfer between location and transport vehicle) may eliminate the advantage of the helicopter’s speed by requiring additional ground time, increased patient risk, and transfers between vehicles to travel between the landing area and the referring facility. In most cases, the patient should not be delivered to a distant landing zone to meet the aircraft and transport team. During this period of transfer, the clinical care and monitoring of the patient may not be optimal, and a lack of interventional capability creates an unstable environment. In addition to the potential for disruption of the care of the patient, any patient transfer between different types of vehicles may be challenging, especially if there are size limitations. Patient movements necessitated from multiple patient trans­fers may be detrimental to the patient’s medical condition. If the helicopter must land in a location away from the site of patient care, ideally, the critical care transport team will be transported to the patient rather than the patient

to the air ambulance.

If airplane versus helicopter transport is considered, in addition to distance issues, the ability of the helicopter to arrive directly at the hospital or nearby landing zone must be evaluated and compared with the airplane landing at a more distant airport and the requirement for an ambulance to travel the distance between the referring facility and the airport.

The response times of any vehicle selected may be affected by the vehicle's availability and weather conditions. A local air-medical helicopter already may be committed to a transport or may be unable to fly because of adverse weather conditions or maintenance requirements. These con­siderations may require that an alternative vehicle be selected to avoid a significant delay in response time. Fixed-wing aircraft have the advantage of pressurized cabins; therefore, they are able to operate at higher altitudes to avoid weather and turbulence found at lower altitudes.

When promoting a neonatal-pediatric transport program, it is impor­tant to help the referring physicians understand the factors that can affect the response time and what the “routine” response time will be. Confusion may exist for referring physicians, who might anticipate response times from neonatal-pediatric transport programs to be identical to those of EMS agen­cies, local ground ambulance services, or other available transport teams.

Stabilization and Preparation Time

The amount of time spent by the transport team to stabilize the patient's condition and prepare the patient for transport is another important con­sideration related to vehicle selection. Compared with local ground ambu­lance services, critical care transport teams that arrive by air or ground often take more time to assess a patient and stabilize the patient's condition before transport. Critical care teams should have a minimum of 2 personnel accompany a critically ill patient. This may consist of a combination of phy­sician, nurse, respiratory therapist, and critical care technician (see Chapters 3 and 4). A critical care transport team is an extension of an intensive care team. Sophisticated neonatal-pediatric assessment, evaluation, stabilization, and treatment of the patient are necessary. A helicopter transport service will need to consider these issues regarding potential prolonged downtime at the referring hospital, which may remove them from EMS or other responses and can add to the per-capita cost for transport.

Out-of-Hospital Time

For a patient in unstable condition or for a time-critical transport, the out- of-hospital time may be the most important factor in the transport vehicle equation. In addition to the distance between the referring and receiving facilities, the total time spent between facilities in the transport environment will depend on the mode of transport and the related times and logistics necessary to get to and from the vehicle. Like the response time, the out- of-hospital time will be affected by off-site helicopter landing zones and travel to and from airports. The transfer of a patient from one vehicle to another is time-consuming and recognized as a particularly risky time in the transport of any critically ill or injured patient. Temperature instability may occur during the transfer. Equipment is most likely to become discon­nected or fail during transfer between vehicles, and, as mentioned, monitor­ing of the patient's condition is more difficult.

The philosophy and practice of many neonatal-pediatric transport teams may lead to a different approach to the linking of the response time, stabilization time, and out-of-hospital time than is usual with other transport services. For example, to reduce the response time for transport of a critically ill patient, a team may be dispatched to a referring facility by helicopter but may return by ground ambulance after stabilizing the patient's condition, making the helicopter available for other transports during a sometimes prolonged stabilization period.

Vehicle Selection

Many makes and models of ground vehicles, helicopters, and airplanes used to transport patients are available. When evaluating a transport vehicle for neonatal-pediatric transport, specific aircraft or ground ambulance capabili­ties should be studied to ensure that the program uses the vehicles that best serve its mission. Vehicles should be assessed to determine the usable cabin space and available options for the medical configuration. The speed of transport and vehicle range also may be important considerations, and noise and vibration are inherent factors for all transport vehicles and the transport environment. If aircraft are under consideration, additional specifications to evaluate include single engine versus multiple engine, useful load (amount of weight that can be lifted in specific weather conditions), and cabin pres­surization (airplanes). From an administrative and financial standpoint, the costs related to purchase or lease and operate transport vehicles should be evaluated carefully. Some organizations that provide transport contract with private service(s) for vehicle provision. Contract negotiations may include response time of the vehicle crew, vehicle configuration, supplies and equip­ment needed during transport, determine of team composition and determi­nation of billing services.

The ideal transport vehicle should be safe, fast, quiet, comfortable, and medically equipped to care for pediatric and neonatal patients. It should be large enough to appropriately secure 1 or 2 patients for transport with 2 to 4 transport team members. The vehicle should be easy to load and should allow the caregiver easy full access to the patient with seatbelts in place.

Safety

Safety must be the most important consideration in patient transport. A careful consideration of the risks and benefits of the different modes of transport should be completed before any patient transfer. This is also a requirement of the referring physician under EMTALA. Everyone involved with patient transport is responsible for overall safety in and around any transport vehicle. The selection of reliable and safe vehicles (ie, ground ambulances, helicopters, and airplanes) is as important as the training and experience of the pilots, drivers, and mechanics responsible for their opera­tion. Only transport services (air or ground) with a demonstrated commit­ment to safety should be considered.

Accidents have occurred with all modes of patient transport. Collisions and crashes involving neonatal-pediatric transport teams are uncommon but have been reported. Data obtained by King and Woodward¹ from neonatal and/or pediatric transport teams suggest that 1 collision or crash occurs for every 1000 patient transports. Collisions or crashes involving injury were less common and reportedly occur at a rate of 0.546 per 1000 transports. In their 5-year incident review, all 8 reported neonatal-pediatric transport personnel deaths occurred as the result of aircraft crashes. Ground ambulance collisions accounted for some moderate to severe injuries. The aircraft crashes usually resulted from pilot error or adverse weather conditions, whereas ambulance collisions were most often attributed to issues related to the driver, weather, mechanical breakdown, or a third party.

In January 2006, the National Transportation Safety Board (NTSB) issued the “Special Investigation Report on Emergency Medical Services (EMS) Operations” and included, in detail, the briefs of 7 EMS accidents.² It noted that 55 EMS aviation accidents occurred in the United States between January 2002 and January 2005, resulting in 54 fatalities and 18 serious inju­ries. Summary statistics for the 1990-2005 period revealed 125 accidents, with 41 of those involving fatalities. During that period, there were 109 fatali­ties, 43 serious injuries, and 47 minor injuries reported. Although the num­ber of flight hours increased from approximately 162 000 in 1991 to 300 000 in 2005, the accident rate also increased. The NTSB identified the follow­ing recurring safety issues: less stringent requirements for EMS operations conducted with patients on board; a lack of aviation flight risk evaluation programs for EMS operations; a lack of consistent, comprehensive flight dis­patch procedures for EMS operations; and no requirements to use technolo­gies, such as terrain awareness and warning systems to enhance EMS flight safety. Their specific conclusions included the following:

1. The safety of EMS operations would be improved if the entire EMS flight plan operated under Airworthiness Standards (14 CFR Part 135) opera­tions specifications; 35 of the 55 accidents in this special investigation occurred with crew members but no patients on board.

2. The minimal contribution of medical personnel to the safe operation of EMS flights is not sufficient to justify operating EMS positioning flights under the less stringent requirements of General Operating and Flight Rules (14 CFR Part 91).

3. The implementation of flight risk evaluation before each mission would enhance the safety of EMS operations.

4. Formalized dispatch and flight-following procedures, including a dedi­cated dispatcher with aviation-specific knowledge and experience, would enhance the safety of EMS flight operations by providing the pilot with consistent and critical weather information, assisting in go/no-go deci­sions, and monitoring the flight's position.

5. The use of terrain awareness and warning systems would enhance safety of EMS flight operations by helping to prevent controlled flight into ter­rain accidents that occur at night or during adverse weather conditions.

6. If used properly, night vision imaging systems could help EMS pilots identify and avoid hazards during nighttime operations.

Because of the dramatic rise in fatal helicopter EMS accidents that occurred in 2008 (13 accidents, 29 fatalities), the NTSB issued a Safety Recommendation to the Federal Aviation Administration in September 2009.³ The NSTB made the following recommendations as a result of public hearings held on February 3-6, 2009:

1. Develop criteria for scenario-based helicopter emergency medical services (HEMS) pilot training that includes inadvertent flight into instrument meteorological conditions and hazards unique to HEMS operations, and determine how frequently this training is required to ensure proficiency. (A-09-87)

2. Once the actions recommended in Safety Recommendation A-09-87 are completed, require helicopter emergency medical services pilots to undergo periodic FAA-approved scenario-based simulator training, including training that makes use of simulators or flight training devices. (A-09-88)

3. Require helicopter emergency medical services operators to implement a safety management system program that includes sound risk manage­ment practices. (A-09-89)

4. Require helicopter emergency medical services operators to install flight data recording devices and establish a structured flight data monitor­ing program that reviews all available data sources to identify deviations from established norms and procedures and other potential safety issues. (A-09-90)

5. Require helicopter emergency medical services operators to report activ­ity on at least an annual basis to include total hours flown, revenue flight hours flown, revenue miles flown, patient transports completed, and number of departures. (A-09-91)

6. Permit the helicopter emergency medical services (HEMS) Aviation Digital Data Service Weather Tool to be used by HEMS operators as an official weather product. (A-09-92)

7. Conduct a systematic evaluation and issue a report on the requirements necessary for a viable low-altitude airspace infrastructure that can accom­modate safe helicopter emergency medical services (HEMS) operations. The evaluation should consider improved collection and dissemination of weather data, the role of automatic dependent surveillance-broadcast, approaches to helipad and designated landing zones, and integration into the National Airspace System. Include in the evaluation process HEMS operators, related industry associations, and hospitals, among others. (A-09-93)

8. Once the evaluation and report as recommended in Safety Recommendation A-09-93 are completed, initiate action to develop this infrastructure. (A-09-94)

9. Require helicopter emergency medical services operators to install night vision imaging systems and require pilots to be trained in their use dur­ing night operations. (A-09-95)

10. Require helicopters that are used in emergency medical services transpor­tation to be equipped with autopilots and that the pilots be trained to use the autopilot if a second pilot is not available. (A-09-96)

The FAA released a Notice of Proposed Rule Making in October 2010, under which helicopter air ambulances would be required to have stricter flight rules and procedures, improved communications and training, and additional on-board safety equipment.⁴ As a result, operators would use the latest on-board technology and equipment to avoid terrain and obstacles and for flying in challenging weather, at night, and when landing in remote locations. These proposed rules would require helicopter air ambulance operators to:

1. Equip with Helicopter Terrain Awareness and Warning Systems

(HTAWS).

2. The proposal seeks comments on requirements for less sophisticated digital flight data recorders (DFDR) dubbed lightweight aircraft record­ing systems (LARS).

3. Conduct operations under Part 135, including flight crew time limitation and rest requirements, when medical personnel are on board.

4. Establish operations control centers if they are certificate holders with

10 or more helicopter air ambulances.

5. Institute preflight risk analysis programs.

6. Conduct safety briefings for medical personnel.

7. Amend their operational requirements to include Visual Flight Rules (VFR) weather minimums, Instrument Flight Rules (IFR) operations at airports/heliports without weather reporting, procedures for VFR approaches, and VFR flight planning.

8. Ensure their pilots in command hold an instrument rating.

The FAA proposal did not take in consideration of all of the recom­mendations that the NTSB has advocated for years (ie, night vision goggles, autopilots). Furthermore, the proposal did not mandate the installation of flight data recorders on helicopter air ambulances. Cost and weight were factors in excluding these items. Future crash data will dictate whether these items will be in forthcoming FAA recommendations.