2015, May/June Adirondac Adirondoc

Regular readers are familiar with my mantra that wilderness medical emergencies are rarely the “big stuff.” Backcountry disasters often begin with problems which, at home, would hardly merit even a trip to urgent care: mild dehydration, sprained ankles, and sunburn, for example. There have been plenty of incidents in which such seemingly trivial matters started a cascade ending in catastrophe. The “first aid” for such episodes is pretty straightforward; it is their occurrence in a remote location that can spell trouble.

Blisters are a terrific example of such a problem. Most of the time, they are no more than a pesky discomfort. However, if they lead to a fall, exhaustion, pushing beyond one’s limits, or even infection, they are a much bigger deal.

Blisters begin with friction between skin and overlying sock or shoe, generally in a prominent location such as the heel or big toe. The friction eventually leads to a separation between the two layers of skin. Ultimately, the space created by this separation becomes filled with clear fluid. If the upper layer of skin is disturbed, it exposes lower layers and becomes exquisitely painful.

Prevention of blisters begins well before one’s trek. Skin that has been toughened by exposure to air, walking barefoot, and occasional alcohol massage will be more resistant to the effects of friction. Wearing one’s usual hiking footwear for a few hours a day before the actual trip will prepare skin for the upcoming stress of long hiking.

I used to be a proponent of a two-sock system for blister prevention on the trail. No longer. Technology has brought us some amazing moisture-wicking socks; of which I have now become a big promoter.

One rarely goes from normal skin directly to blister. There typically is a period of time when the affected area becomes sore and red, a “hot spot.” Recognizing a hot spot early in a trek permits some interventions to prevent evolution into a blister. Covering the area with an adherent such as tincture of benzoin and then applying a generous moleskin over it may help.

Moleskin also is used when a blister actually develops, although the technique is different. Slather benzoin on the intact skin around the blister, cut a hole in a large piece of moleskin just a bit bigger than the dimensions of the blister, and place this “donut” around the blister. Reinforce the entire dressing with strips of cloth adhesive tape. Avoid folds in tape; they could lead to further skin injury.

There are few things as painful to a hiker as a large blister that has become unroofed. The exposed raw skin may make walking nearly impossible. There are several types of dressings for these wounds. Most involve a moist gel dressing which provides pain relief and promotes healing. These come in multiple brands, such as Band Aid ®Advanced Healing Blister.

Here is a very up-to-date and accurate website on blister prevention: au/the-advanced-guide-to-blisterprevention#. VOs9jSzYUdU

~Tom Welch, MD, is professor and chair of pediatrics at Upstate Medical University in Syracuse and an active member of the Wilderness Medical Society. He is a licensed professional guide and a certifying instructor for the Wilderness Education Association, and has guided groups in the Adirondacks, Montana, and Alaska. More information is available at his website and blog:

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Topics: Skin