Lectures

Cold Weather Medicine: Cold and Freezing Injuries

Recording

Q&A

What is the best way to warm in the field with limited resources? Or when nowhere near a hospital at all?

Removing wet clothing and covering in plastic, foil emergency blankets, or dry clothing/blankets is the best option. For digits in frostbite, prioritize rapid transport as field rewarming with improper temperature of water baths could worsen the injury.

Is there a higher incidence of frostbite injuries in patients with underlying Reynaud’s phenomenon? Conversely, is there a role for vasodilators like nitric oxide, calcium channel blockers, or sildenafil to treat developing frostbite in the field?

Reynaud’s is certainly triggered by cold temperatures but Dr. Alvarado has not seen literature about correlations between the two. Dr. Alvarado has not rapid rewarming as the primary mode of treatment. Review of the Wilderness Medical Society clinical practice guidelines shows there is limited data around use of most vasodilators, but iloprost, a prostacyclin analog, has been shown to have benefit when given within 72h from injury.

Is there a role for tPA in frostbite following arteriogram of digits?

Yes! The WMS clinical practice guidelines also discuss positive results for limb or digit salvage when using tPA within 24h of tissue thawing.

Any recommendations for treatment for chronic Chilbains?

prophylactic vasodilators have been shown to be beneficial.

Do you recommend ibuprofen during frostbite rewarming to interrupt the inflammatory cascade. If so, what dosage?

Dr. Alvarado explained ibuprofen has been shown to have beneficial effects when given in the field. The WMS clinical practice guidelines recommend 12 mg/kg at a maximum of 2400mg daily.

In hypothermic patients, are there specific types of patient movements or manipulations that may be most likely to trigger dangerous cardiac dysrhythmias, especially in a prehospital environment?

Anything that would trigger a major cardiac response (rapid supine to standing for example)

Once the core temp reached 32 , is there any risk for hypothermia again?

Yes, this is called after drop, which is theorized to happen due to return of cold blood from the extremities. Dr. Alvarado explains that monitoring of core temperature is especially important for this reason. Esophageal monitor in an intubated patient is best as it is closest to the heart. Other options include monitoring on a foley catheter or with a rectal probe.

Polar Medicine: Practicing Medicine at the End of the World

Recording

Message From the Speaker

Thanks everyone for your interest in my talk! It was a pleasure to chat with you all. One last thing, please make your career what you want of it. There are so many options out there for fun and interesting facets of medicine. That said, how well you perform now and how much you learn now is crucial to any successful medical career. It's all building blocks, so be sure you have a solid foundation.

My best,

Dave

Q&A

What institution prepared you best for international/wilderness medicine?

I trained at HAEMR (Harvard Affiliated Emergency Medicine Residency) which has a very strong international presence and a leader in the field of WM who mentored me. My experience here helped me secure a spot at the Univ of Colorado for a Wilderness Fellowship where my experience doubled.

What is the most dangerous adventure you have been on?

I like to think I take calculated risks. I would love to insert a cool story here, but I've been really fortunate to not have any close calls . . . that I am aware of.

Does each expedition require its own unique preparation? Or, is there a course/training session that prepared you for a majority of your endeavors?

Learning Emergency and then Wilderness Medicine has provided a solid knowledge base so that I can deploy to a number of environments and medical emergencies. I do prepare for each deployment, but it's been years of learning and experience that make me feel ready to handle anything.

How would I begin to become involved in practicing medicine like you? What does it take? What did you do to get started?

Getting started in Expedition medicine or WM is really tough. There are few opportunities for people who are new to medicine. I stuck my neck out there a number of times by cold calling (emailing) a ton of people asking if I can join their team or if they needed a free medical expert. I got a ton of "No's." Getting involved in the field of WM is a lot easier. Join the Wilderness Medical Society (I'm running the winter conference) to network and learn about more ways to get involved. As a med student, a WM elective (take mine at CU when you're a 4th year!) is indispensable.

How are you able to stabilize people in the wilderness with limited resources?

Treating people in a wilderness setting is challenging! It takes training and practice to properly treat a patient when you have very limited resources. It's taken me years to be somewhat good at it, so sadly, I don't have an easy answer.

What types of opportunities are made available by completing formal Wilderness Medicine training?

Above all else, a WM fellowship provides contacts. WM is a tiny field and it's very hard to be someone in the field without knowing other who are in it, and more importantly, them knowing who you are. You can really make the fellowship your own by focusing on projects that spark your interest, but a fellowship will provide many of these opportunities.

Did you see any cases of frostbite?

In Antarctica, we had a number of cases of 1st degree frostbite (or superficial thickness). People would wear enough clothes, but sometimes need to take their gloves off for more dexterity when working outside or work with metal that was -50 degrees. Nothing bad or permanent though - fortunately!

Curious about what your career looks like now - how often do you get to go on expeditions or practice wilderness medicine, vs teaching, EM clinical practice, etc ?

Most of my career now is teaching WM. My students are medical students, residents, and our fellows. I still get to do some expedition stuff (prior to COVID). I feel like I need a few good expeditions a year - making htis year particularly difficult.

What residencies/fellowships would encourage us to pursue if we want to do something as cool as that?

I don't mean to harp on an EM residency, but I do feel that it is hard to obtain the skills to treat someone in the wilderness without it. Clearly, the only medical interactions you have in a wilderness setting tend to be emergencies and unforseen events. It's rare you're managing a chronic illness. I'm pretty certain that only EM docs are being considered for deployments to Antarctica.

How often are medical supplies inventoried/replenished?

We received multiple packages throughout my season. Maybe about 10 or so with meds and supplies. Since no flights occur during the winter months, that's about all you get for the year.

What are the specialties of most physicians on the ice? Mostly EM/IM? Any FM? Others?

Like I mentioned earlier, EM is really the only ones being considered. IM and FM docs as well as some surgeons have been deployed in the past. I worry about medical folks handling surgical issues (basic procedures to running a trauma) and surgical folks managing medical problems (EKGs, chest pain, pneumonias . . . )

Do you do all the tech/nurse duties yourself while down there?

Yup, I am responsible for all the duties such as starting lines, running labs, getting vitals, administering meds. It was a little new to me, but given this wasn't my first rodeo, I didn't have any problems.