Managing Mass Casualty Incidents in the Backcountry

Most people think of wilderness medicine as providing medical care in a remote setting where access to conventional healthcare resources is limited or unavailable. They imagine someone treating a wound, applying a tourniquet, performing CPR, or fashioning a splint out of sticks and a bandana enabling a hiker with a broken leg to hobble to safety. 

Few rarely consider the role of wilderness medicine in mass casualty events such as earthquakes, flash floods, wildfires, and other natural and manufactured disasters. These incidences result in multiple injuries that can overwhelm the resources available to treat the injured.

In the context of a mass casualty event, wilderness medicine providers fill all their traditional roles — caring for the injured and improvising to overcome the lack of medical equipment and supplies. However, their role often expands in scope as they face the challenges of assisting multiple patients at the same time suffering from diverse injuries. 

Meeting this challenge requires knowledge of the system and resources available, along with an ability think and act quickly and rationally in order to triage patients. That means  sorting and prioritizing patients on larger scale, based on the severity and urgency of their medical needs — again in the context of available resources.

Defining “Mass Casualty Incident”

A mass casualty incident (MCI) is any event in which patient needs exceed available resources. The definition isn’t limited to a minimum number of injured parties or the severity of those injuries. It could be dozens or hundreds of patients or only a few — a scenario that’s common in wilderness medicine settings.

The initial response to an MCI is a two-step process:

1. Size up the scene.
2. Triage the injured parties.

Sizing Up the Scene: Bringing Order to the Chaos

Determining that you are dealing with an MCI is relatively easy in the context of catastrophic events such as a major storm or an avalanche. Other cases can be more uncertain. As an example, let’s say you and your fellow field instructors are guiding a group of 10 participants — five men and five women — in the Wind River Range of Wyoming. While attempting to summit a peak before descending a challenging backcountry route, several members of the group experience events that require wilderness medical intervention. One participant falls and suffers a severe compound fracture of the femur. Another develops altitude sickness, and a third becomes severely dehydrated.

In situations like these, you first need to recognize that you’re dealing with a mass casualty incident (MCI). Then, you need to size up the scene, a process that involves a quick but accurate accounting of the following details:

• The number of deceased and injured parties
• The nature and severity of the injuries and the urgency of treatment
• Availability of resources (medical equipment and supplies; food, water, and other essentials; and human resources)
• The location (in the context of access to additional resources and/or evacuation)
• The nature of the terrain
• Weather conditions

As a first responder, your mantra should be “Bring order to chaos.” Maintain a calm mind, think rationally, and focus on organizing the resources you have in order to use them most effectively and efficiently.

Part of the process of sizing up the scene involves establishing who’s in charge. In trips, expeditions, and programs guided by field instructors like those here at The National Center for Outdoor & Adventure Education (NCOAE), the leader will be designated Incident Commander as defined by the group’s Incident Command System (ICS). In unorganized wilderness trips, leadership selection might be less formal. The most assertive or respected of the group typically steps up to maintain control of the situation, organize available resources, coordinate efforts, and calling for further assistance.

After incident management has been established, triage can begin.

Performing Triage in the Backcountry

Triage in a wilderness setting is unlikely to be as formal as using manufactured triage systems, which typically include tags and markers. Simply maintaining a record of patient information and being prepared to pass it on as a more formal system is an acceptable approach. As you evaluate and sort injured parties based on the severity or urgency of treatment, consider using a system such as the following:

• Green — Walking wounded: These are people with minor injuries or conditions that do not impede their ability to function or assist with the care of others. For example, a participant has sustained superficial abrasions and minor cuts from a brush with thorny vegetation. Members of this group are able to walk unassisted, carry their own packs, and help set up camp or assist with group tasks.

Early in your response, you may be directing the walking wounded to assist in moving patients with more severe injuries into certain tents while the deceased are located out of view (to maintain morale among the group).

• Yellow — Delayed: This category includes people with serious but not immediately life-threatening injuries or illnesses. Treatment can be temporarily delayed without severe consequences. For example, someone in the group is suffering from a dislocated shoulder after slipping during a climb. While painful and immobilizing, their condition is stable, and their vital signs are normal. Here, the injury can wait for treatment after more critical patients have been cared for.
• Red — Intermediate: This category involves people with life-threatening conditions requiring urgent care in order to save their lives or prevent permanent disability. For example, in our above-mentioned Wind River Range scenario, the patient has sustained a severe compound fracture of the femur after a fall on rocky terrain. They are experiencing significant blood loss and showing signs of hypovolemic shock, including pale skin, rapid pulse, and confusion. Immediate intervention is critical to stabilize the injury and control the bleeding.
• Black — Deceased/expectant: This category includes people who are either deceased or have injuries that are so severe that survival is unlikely, even with advanced medical care. Resources are allocated elsewhere to save lives that can be saved. For example, a participant in the group was struck by falling debris during a rockslide, resulting in a severe open skull fracture and unresponsive status. Despite initial attempts to assess their condition, their injuries are incompatible with life in the remote setting in which you find yourself.

While most wilderness medicine events are minor, requiring only quick and easy treatments, the examples of incidents involving multiple patients requiring treatments of extended duration are numerous. Maintaining readiness to intervene in mass casualty incidents is a valuable competency area for anyone interested in the field of wilderness medicine and anyone who would like to be helpful when such incidents arise.

If you’d like to learn more about wilderness medicine, including courses to help you prepare for your next backcountry adventure or career in outdoor education or wilderness programming, please visit the Wilderness Medicine page on our website.

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About the Author: Todd Mullenix is the Director of Wilderness Medicine Education at The National Center for Outdoor & Adventure Education in Wilmington, North Carolina.

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