Two doctors are about to ski more than 2000km across the snow, ice and blizzards of Antarctica, saying their combined medical know-how will help them survive.

Dr Gareth Andrews and his brother-in-law Dr Richard Stephenson left Australia on Thursday to begin their historic journey.

The pair are attempting the longest unsupported coast-to-coast crossing of the continent by ski. They will face sub-zero temperatures — averaging -30°C — while battling storms and high winds and dodging the crevasses. 

But it is often the medical issues ranging from chest infections and gastrointestinal upsets to serious injuries and infected blisters that can bring a team unstuck, said Dr Andrews, a Sydney anaesthetist.