Concussions and brain injury have gained much media notoriety, frequently in relation to professional sports and military combat injuries. Currently, there is a dearth of literature on incidence, outcomes, and treatment of concussions in remote settings, so wilderness providers must rely on related research from organized sports and the military. Here we review some background and concepts on diagnosis and treatment of brain injuries and the complexities of managing these in remote settings.
The American Medical Society for Sports Medicine defines concussion as “a traumatically-induced transient disturbance of brain function that involves a complex pathophysiological process.” Concussion does not always result in loss of consciousness, does not require direct impact to the head, and is not detectable by standard CT and MRI imaging. Concussion does involve damage to neurons that result in slowed axonal transport, changes in membrane permeability and altered energy utilization in the brain.
When dealing with a potentially brain-injured patient outdoors, initial priorities are mitigating hazards of the environment and immediate life-threats (ie, “airway, breathing, circulation”). Once these are addressed, patients may be screened for a severe brain injury and possible concomitant cervical spine injury. Possible indicators of a severe brain injury include prolonged loss of consciousness or persistent Glasgow Coma Scale (GCS) less than 13, extremes of age, anticoagulation or hemophilia, acute or chronic substance abuse, seizure, signs of skull fracture, persistent vomiting, a high energy mechanism (such as falling off a cliff or high-speed collision), or symptoms getting worse with time. If the patient has any findings concerning for a severe brain injury, treat associated injuries as appropriate and prepare to evacuate urgently.
Once severe brain injury is deemed unlikely, a more focused evaluation for concussion can proceed. Signs and symptoms suggestive of concussion include headache, neck pain, emotional or behavioral disturbance, memory problems, confusion or cognitive challenges, nausea, blurred vision, poor balance, slow responses, feeling drowsy or “slowed down,” and sensitivity to light, noise or motion. While patient-reported symptoms are useful, it is not uncommon that concussed patients will attempt to conceal or minimize their symptoms. If the patient is denying symptoms and there are still concerns of a possible concussion, consider the overall appearance of the patient and the quality of your interaction. If the patient is holding their head, slow to answer and irritable with the evaluation, concussion should be considered.
Additionally, some functional tests of the brain can be performed in the wilderness setting as well as on the sidelines. Evaluate recall and cognition by asking about the plans and activities of the day with questions like: What route are we on? Where did we put in on the river? How far to our objective? Who led the last pitch? Where are we staying tonight? Familiarity with the activity and a little imagination will help you create reasonable questions. Further testing includes having the patient repeat sequences of three numbers backwards (eg, “5, 7, 1” repeated as “1, 7, 5”) or performing simple, familiar tasks like tying a knot, orienting a map, or making a phone call. If any of these activities are slow, difficult or evoke increasing symptoms, concussion is likely. The near point convergence test is also potentially useful and can be easily done in the backcountry. Screening tools commonly used in sports medicine such as the SAC (Standardized Assessment of Concussion) and SCAT-5 (Sideline Concussion Assessment Tool 5) provide a more objective evaluation that is very useful in follow up visits, and even more so when pre-injury baseline data is available.
When a patient is injured in the backcountry, the decision to evacuate and whether to call for outside help will depend on many factors and should be individualized to each situation. If the patient is concussed, there are some factors to keep in mind. Concussed patients have measurable and significant difficulties in balance, judgement, reaction time, and impulsivity. Problems with cognition and ocular tracking will limit situational awareness. As such, the patient could be a significant risk to themselves or others in difficult terrain. Research has proven that continued significant exertion will worsen symptoms and prolong recovery, even absent a second injury.
If you work with youth outdoors in the US, be aware that every US state now has a youth concussion law. While these laws vary from state to state and tend to be more focused on traditional scholastic and league-based sports, they have important requirements. These laws generally mandate that a youth with suspected concussion must be removed from sport and not allowed to play sports the same day of injury. Most also mandate professional medical evaluation before return to activity and education about concussion for coaches.
In conclusion, concussion is an important diagnosis in outdoor activity both medically and legally. As a wilderness medicine clinician, you should be familiar with how to prevent, recognize, and manage concussion. The WMS is currently forming clinical practice guidelines for the treatment of traumatic brain injuries in the wilderness. In the interim, wilderness providers can seek further education on concussions at places such as the CDC’s “Heads up to Health Care Providers” Program, the AMSSM position statement on concussion in sport, and the Sport Concussion Assessment Tool, 5th Ed (SCAT5), among others.