Lukla airport is perched precariously on a high mountainside in northeast
Nepal: each morning tiny planes skim the ridge on the far side of the valley
and land on a short, sloping runway that juts into the abyss and ends
alarmingly with a high stone wall, depositing climbers who are on their way
to Everest.
The airport staff were puzzled, then, to see the 8.30am Yeti Airlines flight
from Kathmandu disgorge nine rather high-spirited British children.
The Sherpas who had arrived to meet the flight watched in bemusement as the
children spilled out of the gates, playing and fighting and falling over and
grazing knees. Little did they realise that they were witnessing the start
of a medical experiment.
Accompanied by their parents and a grandmother, and encouraged, dragged and
occasionally carried by the Sherpas, the children would ascend to above
11,000ft (3,350m), while being monitored by a team of child physiologists.
They were guinea-pigs in an experiment to test the effects of altitude on
young children.
The Smiths Medical Young Everest Study had begun as a plan for a family
holiday. Monty Mythen, Smiths Medical chairman of anaesthesia and critical
care at University College London (UCL), was to set up one of a series of
laboratories on the route to Everest Base Camp, which would test the effects
of altitude on 208 adult volunteers as part of the Caudwell Xtreme Everest
project.
The effects of climbing to high altitude, where the group would be breathing
in far less oxygen, replicate the effects of critical illness. About 25 per
cent of people adapt quickly, 50 per cent adapt more slowly. A remaining 25
per cent fail to adapt at all: in intensive care they die, and in the
mountains they may die unless they descend quickly.
“If we can find the physiological switches that help some people adapt to low
oxygen levels, we will save lives,” Professor Mythen said. The only problem
was that the results could not be applied safely to young children. The
professor had a solution: he hoped that his family would visit him at his
laboratory. He suggested running a similar set of altitude tests on his own
children, and on four of his nieces and nephews. Dr Samatha Sonnappa, a
respiratory paediatrician who was to accompany the expedition, offered her
own son as a ninth participant. Smiths Medical, which has spent £4 million
on research at UCL and produces respiratory devices, agreed to sponsor the
trip.
The proposed study caused controversy when it was reported in The Timeslast
month. “Friends thought we were absolutely mad,” Professor Mythen’s wife,
Kate, said.
The expedition began inauspiciously. The group had not even left Lukla when
Harriet Themans, 11, felt sick. While she was being treated, Alice Mythen,
9, fell and twisted her ankle. She could hardly walk: it seemed unlikely
that she would manage a day of trekking on a rocky path in the Himalayas.
Tom Mythen, 6, the youngest participant, fell over on his nose.
Janet Stocks, Professor of Respiratory Physiology, who was in charge of the
medical team, tried to keep calm. “I just thought, ‘What have we let
ourselves in for?’,” she said.
Half an hour later, with Harriet feeling a little better and Tom showing
almost no sign of his encounter with a paving stone, the children set off.
Alice joined them, limping and supported by her mother and a Sherpa. As well
as the medical team and the parents, there were 20 Sherpas and porters,
carrying clothes and several boxes of medical equipment, and two Sherpanis
to look after the smaller children.
If the scientists of the Victorian era took family holidays, they must have
looked like this.
Kalsang Sherpa, head of the Walking and Climbing Company, was in charge of
logistics. “I have done many horrible things in my life,” he said. He once
fell 140ft into a crevice on the Western Cwm, the glacier that fills the
southwest side of Everest, ripping the skin off one side of his head. He has
never worked with children. “British children are quite spoilt,” he said. “I
want to teach them what things are like here.”
The children had arrived equipped with six handheld computer consoles but were
forced to leave them behind in Kathmandu. “I never thought I’d say this,”
said Charlotte Mythen, 11, after trekking for 17 minutes. “But I really miss
my Game Boy.”
The older girls coped with the loss by making up rude songs; the younger boys
by treating the walk as a military operation. “This is a sniper’s rifle,”
said William Ogden, 10, holding up his trekking pole. “I also have a Gatling
gun and some grenades.”
Professor Stocks was worried: at the rest stops it seemed impossible to make
the children rest. William’s mother, Caroline Ogden, told The Times:
“I had thought the altitude might slow him down. It does not seem to have
had any effect.”
She sounded very slightly dispirited. At Lukla the air pressure is about 25
per cent less than at sea level, and oxygen levels in the children’s blood
fell from about 98 per cent saturation to 92-94 per cent. All the children,
that is, apart from one, who appeared relatively unaffected. As they climbed
higher she appeared to display the characteristics of a high-altitude
mountaineer, until they approached 10,000ft, whereupon her oxygen levels
fell back and those of the other children recovered.
The medical team also tested the heart rate of the children, how fast they
were breathing, their short-term memory, their lung capacity and the blood
flow to the brain. On steps beside a Buddhist stupa, they carried out
exercise tests. There were sleep tests too, when the children went to bed in
“life vests” that monitored heart and respiratory rates and their blood
oxygen levels.
On the second day of trekking the path cut along a deepening gorge,
occasionally swinging out over a foaming green river on high-wire bridges.
Katrina, 7, is scared of heights, and crossed them while holding hands with
her grandmother, singing Twinkle Twinkle Little Star. Later she began
to feel dizzy and had to be carried by a Sherpa named Nima.
“Are we there yet?” the children asked. “Very near,” the Sherpas replied. They
were passing into a landscape of increasing grandeur: jagged peaks piled
with snow rose on all sides. The children sometimes seemed immune to it all:
“Ate some dodgy porridge, seen some yaks, met a monk and walked up all these
hills,” Harriet said that evening.
The final day of the trek was the most gruelling: the path tumbled down
between two cliffs and then rose steadily and continuously. A horse arrived
to pick up Grandma, who rode among the trekkers, like a general among an
army of marching child soldiers. The air grew thinner, the children
struggled harder to breathe. Professor Stocks said: “This is how it feels
for children with leukemia.”
As they climbed the final 2,000ft to Namche Bazaar, where Professor Mythen was
waiting in his laboratory, the trek turned into a straightforward race.
William had complained that the adults were slowing him down, he led the way
with Patrick Mythen, 13, the oldest of the children.
Alice said: “I was so relieved to get here. I nearly cried when I saw my dad.
I have never really cried when I have been happy before.”
The medical tests continued. The researchers hope that analysis of the results
will reveal why different children adapted at different rates to the low
oxygen levels, and in turn that this will open the way for new treatments
for children with chronic lung disease, cystic fibrosis, sickle cell disease
and sleep disorders.
Professor Stocks said: “The range of responses we have seen will also help us
develop treatment for children in intensive care tailored to their needs.”
This week the children climbed higher, to 12,700ft, where the air pressure is
64 per cent lower than at sea level. Most will turn back there (including
William, despite his own modest plans to summit Everest), but Patrick plans
to push on to Everest Base Camp, at 17,600ft, where the air pressure is 50
per cent lower than at sea level, and climbers, breathing in 50 per cent
less oxygen, have to fight for every breath. “I hope I make it,” he said.
Dizzy heights
— Some people suffer mild symptoms of acute mountain sickness (AMS) at 2,000m.
Above that altitude, climbers try to stick to “the 300m rule”, not ascending
more than 300m a day
— Above 3,000m 75 per cent of people suffer mild symptoms. These include
lethargy, headaches, mild anorexia, nausea, a feeling of breathlessness and
disrupted sleep patterns
— Severe forms of AMS include high-altitude cerebral oedema, (HACE), and
high-altitude pulmonary oedema, (HAPE). HACE involves fluid leaking into the
brain; HAPE occurs when fluid builds up in the lungs. Both can be fatal if
the victim does not descend as fast as possible
— At Everest Base Camp, at 5,300m, many climbers also report vivid dreams,
sometimes horrifying, sometimes pleasant. About 40 per cent of climbers also
suffer retinal haemorrhages
