The doctor who dropped his trousers on top of the world

That's how Daniel Martin measured his blood oxygen level – and found a more effective treatment for his patients

Dropping your trousers near the top of the world's highest mountain in a 20-knot wind and with the temperature at -25C might seem a foolhardy thing to do – even in the interests of science.

Daniel Martin, 35, a member of a team of doctors who climbed Everest, did it – and it guaranteed him a place in the record books.

The anaesthetist and critical care specialist from London had the lowest blood oxygen level ever recorded in a human being – one that was previously thought to be incompatible with life. Yet at the time the sample was taken – from his femoral artery (in the groin) on a tiny ledge 400m beneath the summit of the mountain – he was walking and talking normally, and even took blood samples from his colleagues.

"It was a reasonably unusual thing to do and it attracted a lot of attention from other climbers on the mountain," he admitted yesterday. "But safety was our main priority. It was so exposed and windy on the top [where they had planned to carry out the procedure] that we decided to drop down a bit. We had done it many times before – it was well rehearsed."

The experiment, the results of which are published in the New England Journal of Medicine, was designed to throw light on the care of patients with conditions leading to critically low levels of oxygen such as cystic fibrosis, emphysema, septic shock and "blue baby" syndrome. Dr Martin's blood oxygen level (2.55 kilopascals) was 80 per cent below the normal level (12-14 kPa) and less than half that which would normally trigger urgent admission to intensive care.

Almost 200 people were involved in the expedition, including 60 researchers, who were members of the Caudwell Xtreme Everest team led by Mike Grocott, head of the Centre for Altitude, Space and Extreme Environment Medicine at University College, London. A battery of measurements were taken of the physiological changes that occur when oxygen is scarce but the headline result was the exceptionally low blood levels observed in Dr Martin and three colleagues.

Dr Grocott, who was himself one of the summiteers and had a blood oxygen level only slightly higher than Dr Martin's, said: "It is a unique and extraordinary finding. We don't see these levels in conscious patients, in fact we don't see them at all – only in people in the middle of a cardiac arrest. Yet we were talking fluently on the radio, moving around and performing the procedure."

The climbers had made their final push for the summit from Camp 4, just below 8,000m on the South Col, at 9.30pm on 22 May 2007. After climbing through the night they reached the summit at 6.30am before descending to the Balcony, a tiny ledge and the first flat ground below the summit. There, they removed their oxygen masks, so their lungs could adjust to the low oxygen atmosphere, and erected a small tent. One by one, they crawled into it and unzipped their down suits while a colleague jabbed a needle into their groin.

Once the four blood samples were collected, a Sherpa carried them to the improvised laboratory they had established at Camp 3, making the almost 2,000m descent in an astonishing two hours, where they were analysed.

The explanation for the climbers' survival, despite their low oxygen level, was a combination of acclimatisation – they had spent 60 days at high altitude – and genetics which allowed them to use oxygen more effectively, Dr Grocott said.

"The fascinating thing about this is that it helps us understand how patients tolerate and adapt to hypoxia [low oxygen levels]. The question it raises is, can patients adapt? Some of the interventions we use – giving oxygen, aggressive ventilation – can be harmful. If patients can tolerate lower levels of oxygen so we can back off, then we might cause less harm."

Blood oxygen: How low can you go?

A headache, fatigue and shortness of breath are among the first signs that someone has too little oxygen in their blood. Further reductions can result in dizziness, confusion and feelings of euphoria and/or nausea. The skin also becomes bluer as haemoglobin cells have a darker colour when not carrying oxygen.

The most serious effects are seizures, a coma and ultimately, death. As part of the body's natural response to low levels of oxygen or "hypoxia", it will increase the amount of haemoglobin in the blood.

This is seen during the acclimatisation process at altitude, but as the blood becomes more viscous or "sticky", it forces the heart to work harder to pump it around the body, and can lead to a heart attack.

Susan Sarandon described David Bowie as
peopleSusan Sarandon reveals more on her David Bowie romance
sportDidier Drogba returns to Chelsea on one-year deal
Arts and Entertainment
The Secret Cinema performance of Back to the Future has been cancelled again
Life and Style
Balmain's autumn/winter 2014 campaign, shot by Mario Sorrenti and featuring Binx Walton, Cara Delevingne, Jourdan Dunn, Ysaunny Brito, Issa Lish and Kayla Scott
fashionHow Olivier Rousteing is revitalising the house of Balmain
Life and Style
ebookA wonderful selection of salads, starters and mains featuring venison, grouse and other game
Arts and Entertainment
Christian Grey cradles Ana in the Fifty Shades of Grey film
filmFifty Shades of Grey trailer provokes moral outrage in US
BBC broadcaster and presenter Evan Davis, who will be taking over from Jeremy Paxman on Newsnight
peopleForget Paxman - what will Evan Davis be like on Newsnight?
Louis van Gaal would have been impressed with Darren Fletcher’s performance against LA Galaxy during Manchester United’s 7-0 victory
The new dawn heralded by George Osborne has yet to rise
voicesJames Moore: As the Tories rub their hands together, the average voter will be asking why they're not getting a piece of the action
Dejan Lovren celebrates scoring for Southampton although the goal was later credited to Adam Lallana
newsComedy club forced to apologise as maggots eating a dead pigeon fall out of air-conditioning
Arts and Entertainment
Jo Brand says she's mellowed a lot
tvJo Brand says shows encourage people to laugh at the vulnerable
Life and Style
People may feel that they're procrastinating by watching TV in the evening
Tovey says of homeless charity the Pillion Trust : 'If it weren't for them and the park attendant I wouldn't be here today.'
Rhys Williams
commonwealth games
Isis fighters travel in a vehicle as they take part in a military parade along the streets of Syria's northern Raqqa province
Arts and Entertainment
Southern charm: Nicolas Cage and Tye Sheridan in ‘Joe’
filmReview: Actor delivers astonishing performance in low budget drama
Life and Style
fashionLatex dresses hit the catwalk to raise awareness for HIV and Aids
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
Latest stories from i100
Have you tried new the Independent Digital Edition apps?

ES Rentals

    Independent Dating

    By clicking 'Search' you
    are agreeing to our
    Terms of Use.

    iJobs Job Widget
    iJobs General

    Senior Risk Manager - Banking - London - £650

    £600 - £650 per day: Orgtel: Conduct Risk Liaison Manager - Banking - London -...

    Commercial Litigation Associate

    Highly Attractive Package: Austen Lloyd: CITY - COMMERCIAL LITIGATION - GLOBAL...

    Systems Manager - Dynamics AX

    £65000 - £75000 per annum + Benefits: Progressive Recruitment: The client is a...

    Service Delivery Manager (Software Development, Testing)

    £40000 - £45000 per annum: Ashdown Group: A well-established software house ba...

    Day In a Page

    Evan Davis: The BBC’s wolf in sheep’s clothing to take over at Newsnight

    The BBC’s wolf in sheep’s clothing

    What will Evan Davis be like on Newsnight?
    Finding the names for America’s shame: What happens to the immigrants crossing the US-Mexico border without documents who never make it past the Arizona desert?

    Finding the names for America’s shame

    The immigrants crossing the US-Mexico border without documents who never make it past the Arizona desert
    Inside a church for Born Again Christians: Speaking to God in a Manchester multiplex

    Inside a church for Born Again Christians

    As Britain's Anglican church struggles to establish its modern identity, one branch of Christianity is booming
    Rihanna, Kim Kardashian and me: How Olivier Rousteing is revitalising the house of Balmain

    Olivier Rousteing is revitalising the house of Balmain

    Parisian couturier Pierre Balmain made his name dressing the mid-century jet set. Today, Olivier Rousteing – heir to the house Pierre built – is celebrating their 21st-century equivalents. The result? Nothing short of Balmania
    Cancer, cardiac arrest, HIV and homelessness - and he's only 39

    Incredible survival story of David Tovey

    Tovey went from cooking for the Queen to rifling through bins for his supper. His is a startling story of endurance against the odds – and of a social safety net failing at every turn
    Backhanders, bribery and abuses of power have soared in China as economy surges

    Bribery and abuses of power soar in China

    The bribery is fuelled by the surge in China's economy but the rules of corruption are subtle and unspoken, finds Evan Osnos, as he learns the dark arts from a master
    Commonwealth Games 2014: Highland terriers stole the show at the opening ceremony

    Highland terriers steal the show at opening ceremony

    Gillian Orr explores why a dog loved by film stars and presidents is finally having its day
    German art world rocked as artists use renowned fat sculpture to distil schnapps

    Brewing the fat from artwork angers widow of sculptor

    Part of Joseph Beuys' 1982 sculpture 'Fettecke' used to distil schnapps
    BBC's The Secret History of Our Streets reveals a fascinating window into Britain's past

    BBC takes viewers back down memory lane

    The Secret History of Our Streets, which returns with three films looking at Scottish streets, is the inverse of Benefits Street - delivering warmth instead of cynicism
    Joe, film review: Nicolas Cage delivers an astonishing performance in low budget drama

    Nicolas Cage shines in low-budget drama Joe

    Cage plays an ex-con in David Gordon Green's independent drama, which has been adapted from a novel by Larry Brown
    How to make your own gourmet ice lollies, granitas, slushy cocktails and frozen yoghurt

    Make your own ice lollies and frozen yoghurt

    Think outside the cool box for this summer's tempting frozen treats
    Ford Fiesta is UK's most popular car of all-time, with sales topping 4.1 million since 1976

    Fiesta is UK's most popular car of all-time

    Sales have topped 4.1 million since 1976. To celebrate this milestone, four Independent writers recall their Fiestas with pride
    10 best reed diffusers

    Heaven scent: 10 best reed diffusers

    Keep your rooms smelling summery and fresh with one of these subtle but distinctive home fragrances that’ll last you months
    Commonwealth Games 2014: Female boxers set to compete for first time

    Female boxers set to compete at Commonwealth Games for first time

    There’s no favourites and with no headguards anything could happen
    Five things we’ve learned so far about Manchester United under Louis van Gaal

    Five things we’ve learned so far about United under Van Gaal

    It’s impossible to avoid the impression that the Dutch manager is playing to the gallery a little