For while Nigel Hart, a general practitioner, is trained to save the lives of others, he now is putting his own on the line as he attempts the mammoth task of climbing Mount Everest, the highest summit in the world.

Setting off on St Patrick's Day, Dr Hart will form part of an elite international climbing team, composing of 10 medics who will be studying the effects of low oxygen and how the body naturally adapts to extreme conditions.

The goal is to place a research team on the summit of Mount Everest and make the first ever measurement of oxygen in human blood at this extreme altitude.

Dr Hart completed a full dress rehearsal on the Himalayan peak, Cho Oyu, in the autumn and those taking part in the expedition hope to attempt the Everest summit in mid-May.

The ground-breaking initiative has been four years in the making.

Dr Hart will be accompanied on the trip by two doctors from the Republic. One of those fellow trekking medics, Roger McMorrow, based in Dublin but who originates from Lisburn and gained his degree in medicine at Queen's University, will be testing a new closed circuit breathing system he designed to be highly efficient at delivering oxygen.

Dr McMorrow said: "Our new system is designed to assist patients, ranging from children with cystic fibrosis to adults with chronic lung disease, to anyone dependent on supplementary oxygen, to be as mobile as possible.

"Where better to test the new CXE Closed Circuit system than in one of the world's most inhospitable locations Mount Everest - where less than half the amount of oxygen prevails than exists at sea level."

The first Irishman to reach the Mount Everest summit in May 1993, Dawson Stelfox, paid tribute to the courage of the Belfast doctor and his colleagues.