Michaela Cartner, an Intensivist and ED physician from Queensland's Gold Coast, gives a fascinating talk on environmental heat stress. The Marathon des Sables provided a perfect backdrop to discuss this important topic.
19. Heat Exhaustion
•Water depletion
•Salt depletion
“ Voluntary Dehydration”
2/3 of net water loss
replaced
•Treat with Saline if orthostatic
•Replace with free water
<2mOsm/hr.
20. Oral rehydration should include
cool fluids with 7% carbohydrate
Absorbtion 30% FASTER THAN
FREE WATER
21. Heat Stroke
“ While I was coherent, I
saw some amazing
sights.…
Runners passing out at
the top of the dunes
and tumbling to the
base
- one elite runner broke
his leg…”
Perratt.me.uk Jackson Griffith
23. Heat Stroke- Treatment
• It does not take long either to boil an egg
or cook neurons.
D. Hamilton
The Immediate Treatment of Heatstroke Anaesthesia 1976; 31:270-272
Tougest foot race in the world 6 marathons in 6 days 250kms longest stage 97kms. Carry everthything on yr back exept water and a tent
Loose fitting clothing maximizes convective and evaporative heat loss. When air temp exceeds mean skin temp heat transfer is reversed average temp is 55C to 5’ at night
We make 100kcal/hr
We make 100kcal/hr
The automotive analogy Exertional heat stroke
Temperature wind chill radiation Physiological ones as well the army uses it for accclimatised and non acclimatised
Why would you use a wet globe when you are running with fanatics likje these??
Say it takes between 5-60days to toughen up you feet
Aldostrone increases and percieved central volume deficit Minimal and self resolves. Usually eldery and long periods of sitting and standing Hydorstatic pressusse cutaneous vasodilation and orthostatic pooling
Stomach cramps and delay absorbtion No elevation of body temp and CNS is clear 1/3 to half
100 out of 600 rescued. 2000 amazingly no casualties this year 2 in total
LFTs not up then the diagnosis should be rethought