Wilderness and Rescue Medicine 8th Edition

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Section II: Critical Body Systems

Lower-risk TBI creates more of a quandary when your evacuation options are less than ideal. Most of these will recover without serious problems and the risk and expense of emergency evacu- ation usually exceeds any real benefit. This cre- ates the common backcountry medical dilemma: Evacuate now, or wait and watch? There are no absolute rules to fit every situation, but there are some general guidelines to help with your risk/benefit assessment. As mentioned above, there is a low probability of increasing ICP when mental status returns to normal shortly after the event. By “normal,” we mean awake, alert, and making sense. By “shortly,” we mean within three hours or so. During this observation period, you should see steady improvement in memory and mental status. If so, there is no emergency and medical follow up can be delayed if necessary. Sometimes, even more ominous signs like anterograde amnesia or loss of distant memory can quickly improve. Anterograde amnesia is the term for the inability to retain new memory and is a form of altered mental status. The patient may literally forget what has been happening from minute to minute as you talk to them. With loss of distant memory, the patient may not recall where they live, how they came to be where they are now, or even their age. In the absence of other serious signs or symptoms, improvement to normal men- tal status relieves the immediate emergency, but early evacuation to medical care is still advised.

Finally, being able to diagnose a TBI means that you can also determine when the patient does not have a TBI. There may be an ugly scalp lac- eration or a broken nose, but if the patient has normal mental status and remembers everything that happened, there is no significant brain injury. Injuries to the face and scalp without a change in brain function do not carry the anticipated problem of increased ICP. Post-Concussive Syndrome Following a blow to the head, some patients experience symptoms including mild headache, photophobia, nausea, sleep disturbance, and dizziness developing a day or so after the injury. Some become depressed, angry, or tearful. This can develop with or without the field diagnosis of TBI. This post-concussive syndrome can last anywhere from hours to weeks, but 3–5 days is typical. Mental status remains near normal, but their discomfort alone may be a good enough rea- son to put the patient ashore or end a backcountry adventure early.

Post - Concussive Syndrome • Can occur without measurable brain injury • May develop quickly or > 24 hours after injury • Normal mental status with:

General Principles

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- mild to moderate headache - blurred vision, photophobia

- disrupted sleep pattern - nausea, loss of appetite - dizziness • Does not indicate elevated ICP • Symptomatic treatment as needed • Non-urgent medical follow-up

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© 2018 WMA

Field treatment is symptomatic: medicate for headache, allow for rest as possible, and avoid activities that require a lot of concentration. Generally, nonurgent medical follow-up is ade- quate. However, progressive worsening or the appearance of new symptoms, such as persistent vomiting, should motivate urgent evacuation.

This helmet damage indicates a high-energy impact and an increased potential for brain swelling and increased intracranial pressure.