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In order to establish guidelines for comprehensive, thorough, and more consistent wilderness medical training, AORE and other organizations that hold a respectively large place in the field of wilderness medicine have signed off on the Wilderness First Responder SOP (Draft), a document that complements the Wilderness First Aid Scope of Practice.

Please consider helping AORE make a difference by reviewing this document if you have ever sponsored a WFR course, attended at WFR course, or instructed a WFR course. Does this document include the topics that you want your staff to know? As a participants of a Wilderness First Responder course, is this training enough to prepare you for backcountry medical emergencies? Are the elective topics sufficient? Please be clear, professional, and thorough.

Click here for the Wilderness First Responder Scope of Practice.

Please send your comments to Tim Mertz (mertzt@uwstout.edu). Comments received will be consolidated and then presented to the wilderness medical providers for consideration in the final document.

Last year we began the ‘Where’s the Man?’ contest and received some great entries! This year, we will be continuing to collect submissions, which will all be posted on our blog and on our Facebook page. At the end of the year, our team will review all of the pictures and captions to select three winners. Those three winners will receive a $50 gift certificate to our online Gear Store.

If you are attending wilderness medicine course through WMA that is three days or longer, you will receive a course t-shirt. Simply take a snapshot of yourself sporting your da Vinci-inspired tee and submit to webmaster@wildmed.com with a caption.

Q:  I sustained a “mild” concussion about a month ago and seem to be doing well.  I am planning to begin work at 3100 m (10,200 feet) starting at the end of the month.  Should I be concerned?  I have worked at this altitude before without any problems.

I do not believe that you should have a particular concern regarding work at altitude because of the recent concussion per se.

Also frequently referred to as a traumatic brain injury (TBI), a concussion is commonly diagnosed clinically when a person experiences any loss of consciousness, confusion, or amnesia following a blow to the head.  Increased intracranial pressure (increased ICP) or brain swelling is the anticipated problem or what we worry about afterward.  The swelling results from bleeding or the accumulation of edema (fluid) in brain tissue.  The early symptoms of increased ICP include persistent vomiting, worsening headache and deterioration of one’s mental state.  It does not sound like you had these symptoms or have this problem now.

Do you have any other symptoms now?  Frequently, following a blow to the head, even without ever experiencing a concussion, people can develop a post concussive syndrome (PCS).  The symptoms of PCS include headache, insomnia, feeling more tired than usual, blurry vision, light sensitivity, difficulty concentrating, feeling off balance, and emotional liability.  These are not signs of increased ICP; they can last for weeks.  If you have any of these, they could get worse at altitude and thereby potentially make you more accident prone.

People who go to altitude, especially over 3000 m (9800 ft), are at risk to develop altitude-related increased ICP called high altitude cerebral edema (HACE).  This is related to the lower oxygen levels and in part, to the resulting reflex increase in brain perfusion or blood flow.  Theoretically, I suppose, if you were continuing to have a slow blood leak from your injury, it could increase in size more quickly as a result of going to 3100 m.  But without ICP symptoms now, this seems very unlikely…unless you sustain another TBI.

I do not know whether a TBI with or without PCS makes one more susceptible to HACE. I doubt it but I could find no substantive references one way or the other.

Bottom Line

If you are feeling fine, go for it and have a great time.  Remember, the best way to minimize altitude symptoms is to ascent gradually, especially over 2500 m (8200 ft).  In addition, increase your physically activity as you acclimate to the new environment.   Some good rules include:

1.  If you can, before sleeping above 3000 m, spend a night above 1500 m (5000 ft).

2.  Above 3000 m, don’t sleep higher than 300 – 500 m (1000 to 1650 ft) above your previous night’s sleeping altitude.

3.  With each 1000 m (3300 ft) in altitude gain, add a rest day and/or sleep at the same altitude for 2 consecutive nights.

If you want more information on altitude, check out The International Society of Mountain Medicine.  They have a nice summary.

Several times each year someone asks in class about the relative danger of an envenomation from a small versus a large crotaline (aka pit viper).  Some people are insistent that smaller snakes are more dangerous.  This idea has always felt counterintuitive to me.  The explanations seem fanciful at best.  Usually, people argue that larger (and therefore older) snakes possess some sort of volume control.  They argue that larger snakes hold back venom against humans because we are not food for them.  These larger snakes want to warn us with a strike but preserve venom for when it matters, like a meal.   I have been unable to find any science and none of the experts that I have spoken with can give a definitive answer one way or the other.  With the publication of a recent study, perhaps this theory will disappear.

This past December the Annals of Emergency Medicine published an article by Herbert and Hayes (2009; Volume 54 #6: p 831) in which they argue that a protective layer of denim over the skin may help to decrease the severity of an envenomation from a defensive strike by a southern Pacific rattlesnake. (I leave you to view the details and decide for yourselves.)   In their study, after provoking a test snake, they presented it a latex glove filled with warm water, one time bare and another time covered with a denim glove.  After a bite, they measured the venom in the water within the latex glove and, when used, on the denim glove.  The order of the trials were randomized and occurred 2 weeks apart.  They found that the amounts of venom measured were consistently and significantly greater from the larger (greater than 66 cm in length) versus the smaller (less than 55cm) snakes.

In the discussion section, they point out the volume differences as well as information from other sources that argue against the smaller is more dangerous theory.  Included are the facts that larger snakes are more likely to strike and that their strikes are more accurate.  Large snakes have longer fangs with larger hollow spaces allowing for deeper penetration and more venom flow.   They cite references (that I did not check) that claim that larger snakes cause more serious envenomations.  Herbert and Hayes state:

Thus, the more effective antipredator deterrent of bites from larger snakes may explain why they resort to biting more readily than smaller snakes.

And maybe Homo sapiens don’t learn to stand back.

Bottom Line

Although the results from this study do not definitively answer the question about size it does lend some scientific basis for debunking an unfounded belief.  Practically, of course, it does not really matter.  The anticipated problem of a venomous snake bite is an envenomation.  There is no good way to predict beforehand who will be envenomated, and if so, how bad it will be.  We treat what we see.  By the way, some skin covering, like denim, seems better than none.

Click here to view the Avalanche POV video clip.

I viewed the link below this PM and am still shaking my head. The introduction to this clip notes:

“This is simply a very sobering and unbelievable video. However, you should take away from this video all the positive things that you can learn from it. Yes there are risks to the backcountry – but with proper gear, training, and guide(s) with avalanche and EMT training – you can greatly lower your chances of getting caught in an avalanche in the first place … and coming back alive if you ever were to get caught in a slide.”

I always thought that we were supposed to AVOID getting swept up in avalanches by steering clear of high risk areas.

David Johnson