Frostbite
By Dr Beth Hall-Thompson
This is my main ‘cold injury’ concern for all of us; so very common at high altitude when under stress, dehydrated and adrenaline fuelled determination running high so distracting climbers from looking after the basics.
Professional explorers may be able to lose digits randomly, but our team find them pretty useful in day to day life and work (toes less so though!)
How will we prevent frostbite?
Keeping all extremities insulated – including nose and cheeks. At extreme high altitude, hands should spend no time outside their well fitted, purpose made gloves. Keeping an eye on each other, buddy-buddy aid, to prevent serious consequences due to lapses in concentration. There can be no tight clothing restricting blood flow, and keeping moving will keep blood circulating throughout. And like hypothermia prevention we need to ensure we are well hydrated and have food inside to fuel our thermoregulatory system.
But if the cold sneaks in?
Then the body will narrow the arteries carrying blood to that area to preserve heat for the core; without warm blood flow and with freezing outside temperatures, the tissues can freeze; forming ice crystals between the cells. Unfortunately the tissues are then destroyed by plasma leakage contents and a lack of oxygen provision.
How do we recognise frostbite?
Pain is the first sign, and not to be ignored; this is shortly followed by numbness. The fingers both look and feel wooden. In the earlier stages, the affected digit generally looks pale or blue/purple, even waxen. Swelling often occurs early; and blistering then follows – these signs still fit into the superficial category i.e. only the skin epidermis, top layer, is involved.
When the blisters are seen to be bigger and containing purplish fluid you know you have got deep enough to involve the blood vessel layer, and any deeper will involve muscle and bone.
Even at these late stages we cannot be sure what the long-term outcome will be; in fact we are unlikely to be sure for another 3-4 months. But we do know that preventing any further cooling improves the outcome; hence an early decision to evacuate must be made.
Management of frostbite on the hill
Only if caught very early and the affected area can be warmed in someone’s armpit until sensation returns within 10 minutes, can the climber go on. Beware – the warming process may be very painful! To continue we need to rectify whatever allowed this to occur in the first place – change wet clothing, check no restrictive clothing, feed, hydrate etc.
If the injury is worse than this then it is the end of their climb; and we need to make arrangements to get the casualty down ASAP, safely and accompanied, without further worsening the injury. Ensure that we replace the boot/glove quickly, because otherwise we may not get it back on due to rapid swelling. Rewarming of these more severe injuries should not be begun until it can be continued; because allowing freeze, thaw and then refreeze will mean an almost guaranteed amputation. None of us will be rubbing either, as it worsens the tissue damage.
What can the doctor do at base camp?
Now we can rapidly rewarm the affected area; in a bucket of warm water between 40-42C, and ensure we keep topping it up to remain that warm for at least 30 minutes. Not forgetting to give pain relief; IV may well be needed!
Feed and hydrate the casualty in the meantime; to try and distract them from the rewarming pain and to aid the recovery process!
Once the colour has returned the limb can be removed from the water and elevated to prevent further swelling.
Now is not the time for any of us to take up smoking as it will worsen the prognosis; and alcohol shuts down our vessels too.
So there is very little high-tech intervention; the only medication known to improve outcome is a large dose of aspirin to thin the blood and improve flow and oxygen carriage.
Then it becomes a waiting game; with daily dressing and being careful to prevent secondary infection of the skin. Specialist assessment in Kathmandu is unlikely to change immediate management; and resolution or death of the tissues will occur in their own time over the next few months.
Even the ‘mummification’ that is freezing of bone and muscle causes bits to drop off, auto-amputation, takes time.