Equipment & Gear, Patient Care, Training

Wilderness Medicine Considerations for the Urban Medic

Issue 6 and Volume 41.

Humans continue to expand their settlement of previously uninhabited areas. This creates the potential for environmental emergencies that might otherwise only occur in a wilderness location. With this continued spread, urban EMS may be expected to respond to calls in these new areas. Due to the nature of the scene, wilderness medicine approaches patient care differently, and necessitates a specialized EMS approach.

Initiating Rescue

Many people think rescue scenarios are as easy as, “We can fly them to here,” or, “With our rescue truck we would just hoist them up.” But it isn’t always that simple. Sure we’ve got choices-air, ground, boat-but there are issues we need to be aware of even if we think we do certain things often enough to be pros.

It’s a generally accepted paradigm of wilderness trekking that all appropriate efforts at self-rescue or buddy assist should be explored and implemented before outside help is sought. Based on the amount of resources and time that go into an organized wilderness rescue operation, often there’s a delay in initiating a response due to the time needed to assemble a rescue party and plan operations appropriately.

Additionally, rescuer safety considerations are paramount and supersede patient condition in any wilderness situation. The unique aspects of wilderness medicine, like extended distances, rough terrain and limited medical resources, mean the safety and well-being of the responders becomes an ongoing part of the operation in ways that urban systems don’t need to manage.

Deciding who can continue on a trip and who needs to be evacuated can be difficult at times. Patients in which evacuation should be considered include patients:

  • With medical conditions that are getting progressively worse;
  • Unable to keep pace with the group due to a medical condition or injury;
  • Having abdominal or chest pain that’s not of clear musculoskeletal origin;
  • With suspected serious high altitude illness;
  • With any injury that has potential for life- or limb-threatening complications (e.g., fractures that are open, markedly displaced, or associated with neurovascular abnormalities); and
  • With psychological symptoms that make them a danger to themselves or others.

In some situations, it may be reasonable for the patient and at least two others to continue the trip if it’s moving in the direction of the closest appropriate care.1,2

Air Transport

Similar to normal air medical operations, air medical services should be reserved for patients who stand to benefit from the increased associated risk. These patients include those with time-dependent injury or illness, or in situations where the increased risk of flight is balanced by large resources required for a prolonged and technical ground rescue operation.

For example, the unconscious patient with head trauma should probably be flown out no matter the ground resources available if flight will get them to definitive care sooner. The patient with rib pain who’s unable to drive his all-terrain vehicle (ATV), but is otherwise stable after a crash and can be a passenger on an available ATV, should go by ATV.

How requests for air transport originate can be somewhat system dependent. Often, they originate with the on-scene responders. However, some localities automatically put a flight on standby or launch based on patient condition as reported by the calling party. For instance, in the case of a motor vehicle collision on a remote stretch of highway, aircraft will be auto-launched to try and save time and get responders on scene sooner. Sometimes, someone on scene specifically requests air EMS.

Decisions regarding the safety of air medical transport ultimately fall to the pilot in command. Activities like flying into unknown topography (especially mountains), night flights, and landing in improvised landing zones increases the risk to air medical crew, rescuers and patients.

Wilderness medicine for urban EMS

Generally, the more technical the rescue, the more important a rigid stretcher becomes. Photo Tim Doyle

To set up a landing zone, there are some basic things you need to keep in mind even when visibility is perfect: size, slope, obstacles, surface and weather. Ideally, a wilderness landing zone is greater than 150 square feet in size. It can be level or angled very slightly (less than 5 degrees) downhill and, ideally, into the wind. The surface should be free of any debris that may be blown by the rotor wash. As a general rule, gravel larger than an inch will be stable on landing and take-off. If possible, snow should be packed down and dusty areas should be wet to prevent whiteout or brownout. Clearly, wilderness conditions can make these considerations more difficult.Weather must also be considered. Most helicopters are only rated for visual flight rules; this means they’re not to fly into conditions expected to result in only being able to fly by instruments. Additionally, most helicopters aren’t equipped with de-icing systems and therefore won’t fly into any suspected icing conditions. High winds also increase risk. Mountains and canyons can have winds that, depending on velocity and direction, may make landing too unsafe to attempt. As altitude and temperature increase, helicopter performance decreases. This results in lower maximum patient weights at high altitude. It also means it’s more difficult for the helicopters to take off and land in small landing zones.

Landing a helicopter isn’t always possible and some areas are lucky enough to have hoisting capabilities and skills, such as Miami-Dade Fire Rescue or the North Carolina Helicopter and Aquatic Rescue Team. If hoist rescue is possible, it’s important to realize their needs or capabilities. It can be a long time before a hoisting team is deployed and ready. In the case of the Air National Guard, specific orders and authorizations need to be obtained before a mission is initiated. Furthermore, sometimes it will be a different helicopter that transports the patient after the hoisting is accomplished.

Rescuers should always be mindful in situations that may delay air transport, such as poor weather, smoke from wildfires, or inadequate landing zones. Ground transport can be initiated with a plan to rendezvous with air transport should conditions improve. Never delay care because you’re waiting on an asset that may or may not arrive.

Patient Packaging

No matter what level provider, patient movement is an EMS staple. In wilderness medicine we learn how to create things we might not have, like litters.

If we’re lucky we have specialized equipment like the Stokes basket, long board, off-road wheeled stretcher attachment, etc., but there isn’t a tool that’s perfect for every situation. Over time we learn to use our equipment efficiently, but we have to take into account special considerations beyond time and cost.

It’s important to have at least one improvised litter you’re comfortable building with your most common kit. After that, there are so many commercial products that all have their own advantages and disadvantages that the important thing is to be familiar with what your local system uses, and maybe what neighboring systems use in case you’re working mutual aid together.2

The litter should be more than just something rugged with handles that we can say we’d have someone carry for us. Most often, not only do you only have what you carry out, you have to carry back what you carry out. The patient also needs to be protected from the elements, immobilized to the degree necessitated by the injury, and hopefully transported with some degree of comfort.

The versatility of a rope stretcher makes it a good tool for wilderness patient packaging. It can be used simply as a soft litter or it can be made rigid with items like pack frames, ski poles and skis, or tree branches. By its nature, it happens to have many handholds.

For a soft stretcher and a short transport, it’s hard to beat just wrapping a blanket or a tarp around a couple of branches or saplings. But, it doesn’t have near the number of handholds and can’t be made as rigid as the rope litter. Generally, the more technical the rescue, the more important a rigid stretcher becomes.

For litter carries, six litter bearers are needed to effectively move a patient over smooth terrain and eight are needed for rough terrain. Because long distances are the expectation in wilderness medicine, allowances will need to be made to change out litter bearers or schedule rest stops. Ideally, 18 or more litter carriers will be available to assist in the transport.

It’s important to have a communication plan for switching out carriers. The most generally accepted method is that the relievers approach from the rear of the litter (usually patients are transported feet first) and everyone advances down the litter with the front-most carriers moving to the back of the line and switching sides to alternate carry arms.

Switch litter bearers about every 400-500 yards or every 10-15 minutes. Again, this depends on safety and patient needs.1 The person nearest the patient’s head is usually the one attending to patient needs because it’s the easiest spot to talk to and continually reassess the patient.

Patient Monitoring & Care

Even though the standards of care are extremely different between hospital and wilderness medicine, it’s still necessary to be able to monitor your interventions as well as a patient’s general condition.

Almost every wilderness medicine training course teaches “the burrito”-a multilayer wrap of blankets and tarps designed to protect the patient from the elements. This technique may have its role, but how can you honestly recheck your patient or your interventions well?

Given the amount of time spent with the patient, it’s important to plan for a way to monitor your patient. Copious amounts of wrapping/blankets can make this difficult if you consider placement of blood pressure monitoring, pulse oximetry and other monitoring adjuncts that might be available prior to wrapping the patient.

Voiding ought to be thought about when the patient is packaged. Elimination needs for the patient are probably going to become an issue even during a prolonged extrication within a city. Consider tilting and letting them void in an improvised urinal, like their water bottle. The approach of “either hold it or just go ahead and wet yourself” is generally a bad idea because it can cause issues with hypothermia, hygiene, comfort, wounds and bandaging.

Not every system has or needs a specific “go bag” to take over a hillside or on a search. When selecting a kit, take into account safety, comfort, and what really makes a difference in patient care while also considering what other team members are carrying. Few wilderness interventions determine if someone will lose their limb or life.

That said, airway and breathing management clearly matter, so basic assessment tools like stethoscope, blood pressure cuff, portable pulse oximeter, basic adjuncts like oropharyngeal and nasopharyngeal airways, and a bag-valve mask are a must. Some airway device like a supraglottic airway is also good to have. Supraglottic airways are often within the BLS scope of practice, and it makes a difference for bagging anyone more than a minute or two. Lastly, for those trained, surgical cricothyrotomy can be employed to save allergic reactions or other causes of supraglottic airway obstruction.

A chest decompression needle is also a good tool to bring, because decompressing a tension pneumothorax can be lifesaving. Additionally, a stab or finger thoracostomy can be employed by those with appropriate training.

Good splinting techniques and maybe even commercial splints for femur and pelvic fractures are a must. Lots of blood loss can potentially be prevented by proper splinting. And if you plan on carrying commercial devices, know how to use other things in case the device breaks or you lose it, which happens.3

Oxygen is something to consider leaving behind. It’s heavy, doesn’t last long and needs to be carried. That oxygen bag on most ambulances is the heaviest thing other than the monitor. Will it really last the time you need? Do you even really need it? For drownings, maybe, but a peep valve on a bag-valve mask might be more important than oxygen. Oxygen is nice to have, but in most wilderness environments it just isn’t feasible.

Most wilderness calls are going to be trauma related, so having an idea of what medications to grab and take with you can make a big difference. Evidence-based medicine has us steering away from simply flooding someone with four-plus liters of fluids, which at least saves us some weight there.

Having a Plan

We think of search and rescue being like television, maybe a manhunt for a fugitive or a hiker who hasn’t returned. We may picture that we would simply call in all resources and volunteers. Many search and rescues, if not all, will entail a multiagency response, but we have to be realistic with who we are and how we can handle something.

All but very simple walkout operations should have an identified ground leader. A well-laid plan should be made regarding the rescue, including anticipated obstacles and safety considerations, patient condition and care needs, available resources, and a proposed timeline, method and route. Ground or water rescues are often both time and personnel intensive. It’s not uncommon for the unit of measure to be days instead of hours, depending on the method of ground transport.

Communication is essential. This includes both being able to share frequencies and radio types. Duplication of services is something to avoid so that money, time and resources aren’t wasted. You also need to have preplanned how everyone will communicate on scene. Information needs to be able to be conveyed across the incident command system from the top down and vice versa.

Realize that although the basic incident command structure should be similar on all scenes, the lead agency may vary by locality. In one place, everything falls under the county sheriff and county fire rescue, other places may have third-party EMS or even have a well-established search and rescue team as the lead agency.

Overall, it’s absolutely necessary to be ready to play in the same sandbox as other services. Know each other’s capabilities and be ready to share jurisdictions and equipment. Search and rescue is no place for egos.

Conclusion

We’re not paid for what we do, we’re paid for what we’re prepared to do. The more experiences we have, the more we realize the many possibilities we need to try to prepare for.

References

1. Forgey W: Wilderness Medical Society practice guidelines for wilderness emergency care. The Globe Pequot Press: Guliford, Conn., 2006.

2. Auerbach PS: Wilderness medicine. Elsevier: Philadelphia, 2007.

3. Auerbach PS: Medicine for the outdoors. Elsevier: Philadelphia, 2006.