I’d just returned from Everest, leading an expedition that completed a new route without oxygen or Sherpa support on the Kangshung Face.
While the climb had been sensational, three of our four team members, including myself, suffered from significant frostbite. Paul Teare escaped unscathed, but Stephen Venables, Ed Webster and I would lose a mix of our fingers and toes that would be a lifelong reminder of what we had sacrificed for our climb.
How you get frostbite, how to prevent frostbite – and how do you treat it?
By Robert Anderson and Dr. Chris Imray
My interest was spurred this year by another chance to guide in Antarctica, where I was fortunate to meet Dr. Chris Imray on Mt Vinson, who is one of the world’s foremost authorities on frostbite, as well as being a talented climber and a Seven Summiter. This fueled more than a few enthusiastic conversations, from Vinson Base Camp, to Union Glacier and back to Punta Arenas, Chile.
We realized there is both a lack of information, misinformation and instances where simple protocol is perhaps not known or followed. As Chris Bonington told me many years ago in Lhasa as he looked over Ed Webster’s fingers following our Everest Kangshung Face climb: “Just don’t let anybody cut them off!”
Seeing or hearing about people who have been misdiagnosed, mistreated, and then at the worst, had amputations that were done prematurely and unnecessarily, spurred Dr Imray and I to share what we know in the hope that it may save a finger or two.
If you grew up in cold climates and climbed in the winter, inevitably you will have gotten cold fingers, warmed them up, it really hurt, and you learned that wasn’t a good idea. Those experiences are invaluable as you now recognize cold, the sensation of cold, the numbness, the inability to even grasp a zipper and the immense headache inducing pain that comes with rewarming.
Your outdoor experience is well worth remembering as you climb into colder climates and to higher elevations – first – just don’t let your digits get cold. And if they start to get cold, stop and warm them up very soon as it will only get worse. Prevention is always preferable.
- How do you get frostbite? What is really happening?
Homeo sapiens emerged on the plains of Africa and have adapted to temperatures in the +20 to +30 C range. So unclothed we are only comfortable at a temperature of 26C, not exactly common in most mountain environments and an immediate indicator we better be prepared the minute we step outside.
To preserve or maintain our core temperature, we shut down or vasoconstrict our blood supply to our extremities in colder conditions.
Then, as temperatures drop below freezing, a combination of vasoconstriction (narrowing of vessels) and hemoconcentration (sludging) reduces the blood flow to our extremities. The only source of body heat to the fingers and toes is through this rapidly diminishing blood supply. The process is worsened by the increased heat loss that occurs when we face:
- windy conditions (wind chill factors),
- increased conductivity in wet conditions and
- vasoconstriction that occurs in response to the increased breathing (or hyperventilation) at high altitude.
The reduced flow and sludging of the blood eventually leads to clot formation (thrombosis) and damage to the lining (or endothelium) of the arteries. With no oxygen (or heat) delivery to the tissues, the cells begin to die.
Your past cold weather experience is important as you will recognize the different ways you get cold. A few hours ice climbing is far different from a long day out (or longer) where you run low on water, get dehydrated, your blood thickens and the warm blood flow to your extremities slows.
Movement, hydration, fuel and food are critical factors. If you aren’t looking after your overall ability to generate heat, it won’t take much to reduce circulation to your extremities.
Your climbing experience will dictate your ability to deal with the environment and control your temperature. While your interest in completing a harder climb may have you focused on technical needs, fitness and climbing gear, the higher dangers of a new climb in a remote area may preclude the planning for higher levels of exertion, longer hours and lower temperatures – and the possibility of a cold unplanned night out.
Our heat gain and heat loss is not unlike a bank balance, with metabolic heat generation on one side and environmental heat losses on the other.
Your rate of heat generation is the metabolic rate and is made up of the basal metabolic rate or background energy production, plus any additional energy production such as that generated by exercise. Your sources of energy are from ether recently ingested food/drink or from stores within your body.
Heat loss occurs through four mechanisms:
- radiation and
- evaporation (sweat and breathing).
A number of interrelated environmental factors will affect your risk of developing frostbite, including temperature, wind speed (and so wind chill), and altitude.
As wind speed increases, so does your convective heat loss. Increasing altitude results in hyperventilation, increased evaporative heat loss and lower exercise levels, thus reducing the metabolic rate and heat production.
Doing a technical route at high altitude on an exposed, windy ridge in the shade, with a low temperature, would maximize heat loss through all four mechanisms, significantly increasing the risk of both hypothermia and frostbite.
If it were possible to simply put on those super filled down mittens you see in the shop, and never take them off, climbers would rarely get frostbite. Unfortunately the minute you need to clip a carabiner, change clothing or hang onto an ice tool and place a screw, those mittens are virtually useless. So what do you do?
- How do you prevent frostbite?
We need to proactively manage our temperature, starting with your core temperature. Matching your heat generation (clothing and rate of ascent) to heat losses (temperature, wind, altitude). Don’t overheat, as your sweat will result in additional evaporational heat losses. With a warm core, your circulation and heat delivery to your extremities is optimised.
The skinny glove/working glove/mitt combination will need to change as the activity changes – ascending, technical climbing and resting. Knowing the temperature, wind chill factor and ‘time to frostbite’ are all good indicators. Don’t hesitate to think fingers first.
Early signs of frostbite are numbness, loss of sensation or a woody feel with/or without a waxen pale white appearance. Don’t touch metal with bare hands below approximately minus 10-15C and use thin gloves for protection.
Your feet – thankfully, with advances in boot technology, in particular the latest 8,000 meter boots (now rated to minus 55/60c), frostbite to the toes has practically been eliminated. Step-in crampons will also speed your time having to touch metal – a very worthwhile investment for the early morning darkness of a big climb.
A few simple learnings – make sure your boots are big enough. A tightening around the ball of the foot, a touching of the toes, the addition of an extra sock that slows blood circulation – can all cause problems. Better to have a bit more room than a bit more sock.
A tip from Borge Ousland, the highly respected and accomplished Polar Explorer, is to allow for a light synthetic liner, not wool, then a thicker insulating wool sock. If you use a wool liner you are more apt to get blisters, as the liner wool sock sticks to the thicker insulating wool and thus to your skin. The liner sock is best if a thin and slippery synthetic material so the heat and friction takes place between the thin synthetic liner sock and the thicker, insulating, wool sock.
Different activities can also induce cold injuries that are very specific. Crampons naturally suck warmth directly from the base of your feet. Descending for long periods cramps toes. Skiing can put specific pressure on different parts of the feet that induce trauma induced frostbite very specific to the activity and can be an area that is not necessarily related to insulation and cold. Ensure your boots fit across all the activities you plan.
If you do get caught out at night, take your boots off and encourage additional circulation. More than a few toes have been saved in high bivouacs when a warm partner is near-by, and you can warm your toes on their stomach. Just another reason to choose your climbing partners carefully.
As your feet will become damp during the day, make sure and dry your socks every night. Foot creams can do wonders at night for soothing wet and tired feet and can help dry and clean your feet, ready for the next day.
If climbers could just put on big mitts, turn on a battery pack or have a good supply of hand warmers that never ran out, your fingers would be fine. But the minute you have to lace up a pair of double boots, put on your crampons, buckle your harness, take down the tent and rope up, those mittens just aren’t going to work – and you haven’t even left camp.
We need to balance dexterity with warmth, while taking into consideration time on the hill, altitude, climbing difficulty and your ability to keep piling on fuel to keep your core warm.
Liner gloves – perhaps it is the name which results in these being used wrongly. While liner gloves work well by themselves in warmer temps or on approaches where you generate a lot of heat – using them as liner gloves inside either gloves or mittens is a very poor use of the heat in your hands.
Liner gloves bunch up and can constrict circulation. In mittens they slow the heat transfer between fingers, which is why you are wearing mittens in the first place. Better to keep the hand free, move quickly when you need to and replace the hands in the mittens quickly. Or slip a pair of light gloves on to keep you warm from an inside pocket for longer tasks like pitching a tent.
Medium gloves/work gloves – with new fabrics and technology, a medium-weight pair of gloves are now warmer than older, heavier models. And trying out the new battery heated glove is looking like a better option all the time. These gloves provide real warmth, wind resistance and cold protection, while still having the dexterity to pitch tents, clip carabiners and place protection. Proper fit is essential but there are a host of models to choose from. Except in the coldest of climates, these can be the glove you end up wearing most often.
Big gloves – the standard here was the the Black Diamond Guide Glove – but there are other similar models now – as well as heated variants. Guides will wear these to the top of Everest, Denali and Vinson, but unseen to the uninitiated, they will be shuttling their fingers from fingers to the palm and back again. And there is also now a variant that groups three fingers together, which may protect your most vulnerable digits.
Yet no matter how warm they are, gloves are nowhere near as warm as a good pair of mittens. On the 8,000 meter peaks, Denali and Vinson, mittens are essential for the higher reaches of the peak.
Lobster gloves – or Soloist Gloves, named after your lone index finger. In viewing a host of frostbite cases, the fingers most often affected are the middle and ring finger on the left hand, followed by the same fingers on the right hand. The dexterity afforded by having the index finger free should be enough to do a host of climbing tasks, so as much as these may look a bit funny, Lobster gloves may be a very good option at keeping your most vulnerable fingers warm.
Mittens – If the ground isn’t too technical, mittens are great, and keep your hands from freezing when gripping ski poles or ice axe. Just don’t bother with liners and move quickly when you take them off. If you need an extended time out of mittens, slip into medium-weight gloves from a warm inside pocket, then back into mittens when you can.
Ice Axes and Ski Poles – The minute you need to grip anything, particularly metal, your circulation is compromised and whatever you’re touching also conducts heat away. Aluminum conducts cold far faster than steel, so wrapping aluminum axe heads and shafts will certainly help. The Grivel Helix now comes pre-equipped with an insulated head, an easy choice for very cold climates.
Hand warmers – The key to hand warmers is to use them to stay warm, not to rewarm or try to warm up when it may already be too late. At higher altitudes, most are far less efficient and if encapsulated in boots or mittens, virtually worthless.
However, a well heated and well placed pad, in the back of a glove or mitten, in the palm, or even inside a gaiter atop a boot, can provide hours of slow burn heat that can be useful. Just don’t expect them to still be burning at the end of a long day. If you get frostbite, don’t use them to rewarm on the hill or even back in camp – much better to have a finger bath for a consistent low heat.
Ed Webster experienced the most amazing sunset of his life above the South Col on Everest, and you can now buy the poster, The Frostbite Sunrise, as it also resulted in the loss of 8 of his fingers. Touching metal in cold conditions with bare fingers initiates frostbite in seconds. Make sure you try out your camera with your gloves on. If you can’t turn it on and take a photo, make another choice.
Your camera phone
With camera phones and touch screens, climbers need to be more aware than ever of how fast their fingers chill. As much as some liner gloves have pads that sometimes work, touching a phone and the need to often use both hands, the time to take photos and then of course, share it to the world, creates a whole host of new ways to get frostbite.
The 7 Recommendations:
- Don’t use liner gloves as liner gloves.
- Spend what you need to get the best hand protection you can, your fingers are worth it.
- Try on every pair of gloves can to get the best fit – we all have different shaped hands and fingers and a good fit is essential for warmth and dexterity. Consider ‘Lobster gloves’ for the coldest climates to keep your most susceptible fingers warmer.
- Always carry a backup pair of mittens in your pack for yourself or a team-mate
- Use hand warmers before you get cold, not after.
- Be very careful using a camera, and in particular, your camera phone.
- Buy warm boots that fit no matter what the activity, snug, never tight.
If you are climbing with a guide or experienced team, you can keep an eye on each others faces for the tell-tale white on the cheek or nose. If that is happening you need to warm and cover or be prepared to descend. Once it turns blue/purple it is too late and you need to head for cover.
Keep the conversation flowing between teammates about how warm you are – keeping in mind hydration and fueling, a key element in keeping warm. Dehydrating throughout the day, becoming fatigued and then pushing to reach camp can easily push one over into getting frostbite when you would normally be fine.
- How do you treat frostbite
A loss of sensation, and a woody numb feeling associated with a waxy pale or white colour, are all early warning signs of frostnip or impending frostbite. Your rapid response may reverse the situation. Make sure and dry protective clothing, both in the affected area and on your core. Get out of the wind and into a group shelter if you can.
Hand or foot warmers can be digit savers and applying them upstream of the cold area can help increase circulation. Taking a hot sweet drink and food will help rewarm the core and encourage circulation as well.
Immediately re-consider your plans for the day. And don’t forget to check others in the group for cold injury. Turn back if necessary – no mountain ever justifies severe frostbite.
- Rewarm the extremity as soon as the risk of refreezing is minimal.
- Apply Aloe Vera – a topical anti-prostaglandin agent, 12-24 hourly
- Avoid weight bearing on frostbitten feet
- Blisters will start to form 3-6 hours after exposure and will need simple dressings
- Pain relief such as ibuprofen 400mg three times daily unless contraindicated
- Ibuprofen also has a powerful anti-prostaglandin effect and should be used initially
- Supplementary oxygen if at altitudes >4000m
- Evacuate to lower altitude and/or warmer conditions
- Seek medical advice either locally or through telemedicine
More serious injuries, particularly when diagnosed early, should be considered for thrombolysis or iloprost. You will need rapid transfer to a unit capable of supervising the treatment. Iloprost is now widely available in Europe and also in Kathmandu, but not currently available in the USA. Ideally the treatment should be started within 24 hours of exposure, but has been useful as late as five days.
Complex frostbite injuries should be managed within a large multidisciplinary team with vascular, plastic (burns) surgery and interventional radiology capability and is often found within a Major Trauma Centre. Ideally the surgical team should have significant experience of dealing with frostbite. Surgery should always be deferred for six plus weeks except in rare instances.
If you have had a significant cold injury, you will be more susceptible to a further injury, either because of an inherent cold sensitivity or because of their previously displayed behavioural traits.
However, you may have learned quite a lot, and have a very strong incentive not to let frostbite occur again.