A Kiwi guide who oversaw the evacuation of ill trekkers en route to Mt Everest Base Camp told them that their health was more important than reaching the summit.
Robert Bruce, founder of the Got to Get Out mobility movement, told The Herald about the evacuation 5050m above sea level, where temperatures plummeted as low as -40C some nights.
Nine days into their trek to Mt Everest Base Camp, six trekkers in the group of 30, including Kiwis and Australians, were struck with the effects of altitude sickness in early January.
Despite a few days spent acclimatising to the high altitudes, including a day in Namche Bazaar 3440m above sea level, some trekkers suffered symptoms of altitude sickness.
Bruce said altitude sickness strikes almost at random and can be fatal if left untreated or if trekkers continue to ascend, Bruce said.
The day before the evacuation, the group, including three Nepalese guides and 11 porters, had battled extreme conditions.
"On the walk from Pheriche to Lobuche, it was a very cold day. It was probably, with wind chill, -25C, and at times snowing.
"This climb was approximately 700m, so one of the biggest climbing days. The group was working hard, and compounding that was the cold."
Bruce explained why the group trekked during the winter season, saying it was far less busy and the views were stunning.
"The freezing conditions made it absolutely spectacular. You've got blue skies most days, white snow, crunchy ice underfoot, you're breathing out steam as you walk.
"It's absolutely beautiful in the Himalayas in winter.
"There's also significantly less people on the tracks. That's not to say that we're the only ones there, we probably passed 50 people a day, going up or down, so it's still a popular route."
Bruce understood the routes were "bumper to bumper" during the summer months.
"There's something very special about putting on a down jacket, putting on a beanie, putting on two pairs of gloves and merino leggings and really battling the elements.
"I think this kind of experience sharpens your senses and makes you aware of your capability and that is what I think you gain from this trek."
The timing of the trip, which began just after Christmas, also lined up with the Kiwi summer vacation, which gave trekkers the minimum amount of time needed, around 15 days, to complete the trek.
After spending the night at The Everest Pyramid Station just past Lobusche, a giant glass pyramid housing a scientific research centre and accommodation en route to Base Camp, Bruce awoke to reports that group members had been sick in the night.
Some had been vomiting, suffering diarrhoea, nausea and headaches.
"Six people were sick enough that we wanted to monitor them," Bruce said.
"We pulled everyone out of their bedrooms that were feeling unwell. It's very easy, and dangerous, to stay in your sleeping bag and sleep, because you feel terrible."
A few of those who were sick began to feel better as the morning wore on, which Bruce said is common with altitude sickness, as symptoms can feel worse after an night of unrest.
But three trekkers remained unwell.
"We had nausea, diarrhoea, headache, high heart rate, low blood oxygenation, dehydration and fatigue - these are classic signs of altitude sickness."
Bruce said he was very lucky to have medical professionals, as well as experienced Nepalese guides with him.
"People were checking blood oxygen, someone was very kindly administering pain medication, nausea medication and so on.
"I think it's the real Kiwi spirit that these people, who were on their holiday, were willing to jump back into their traditional job and I was very grateful."
The medical professionals and Nepalese guides told Bruce the trekkers were not well enough to continue to trek, nor well enough to safely descend to ease their symptoms.
"Descending is one of the only cures for altitude sickness, so if you're feeling terrible, you have a headache, you get down as fast as you can.
"But if you're too sick to walk down under your own steam, then you need help."
Bruce said he had to have a difficult conversation with those who were ill, as he warned that insurance often won't cover the cost of a helicopter flight to hospital if the doctor the trekker sees in Kathmandu doesn't believe their condition was serious enough to airlift them out.
Some trekkers in the past have taken the "easy way home" and insurance companies have tightened up on these free helicopter rides, Bruce said.
He requested a helicopter to take those that were ill to the nearest traveller-specific hospital in Kathmandu.
Within two hours, a chopper arrived to the tea house, 5000m above sea level and took three people to hospital.
There they were put on an IV drip to rehydrate and given antibiotics and insurance was paid out, Bruce said.
One person suffering altitude sickness remained at the Pyramid as the group continued to Mt Everest Base Camp the next day.
Hoping that descending on foot would ease the symptoms, the trekker was later flown out from Periche when their cough would not clear, Bruce said.
Those who were ill were now out of hospital and had recovered well, he said.
Two later flew home early, as the trekking group was still 10 days away from returning to Kathmandu.
But Bruce said some of those who were evacuated were keen to come back and try the summit again, as many said the trek was a bucket-list item for them.
The remaining trekkers continued to Mt Everest Base Camp the next day, where nine of the group split off to attempt a planned climb of Island Peak. Hindered by extreme weather, the group still climbed half way up the 6180m mountain, Bruce said.
Some families and friends had been split, with their loved ones in the group of those that fell ill or went home, so those that made it to Base Camp did it for those that couldn't, Bruce said.
"It was really special, they were waving the flag for the other one."
"We did Everest Base Camp for those that were sick back in Kathmandu."
Bruce, who has led three previous trips to Nepal, said the group was well-prepared, with many safety briefings before and during the trek.
Those in the group all wore appropriate clothing and carried correct medication, and food, drinking up to five litres a water a day.
"I think we did everything we possibly could."
He also worked closely with an experienced Nepal-based trekking company.
"We were prepared and the expectation had been set that some of this group would likely get sick.
"I think people understood the risks and knowingly took them."
An experienced group leader, Bruce said the event was the most testing time for him.
"After it had all happened, and the group had gone, I was quite shaken.
"But in the moment, I felt complete clarity, which was to help the Got to Get Out team members get down, getting well and descending was more important than making it to base camp."
Bruce is considering bringing a doctor with him on future trips, as well as potentially taking a trip in the Nepalese spring.
Back on Kiwi soil, Bruce will continue his many free group or low-cost group events for Got to Get Out, which aims to get Kiwis outdoors and exploring.
The outdoor adventure experiences, organised on Facebook, include paddle boarding, bike riding, treks, ski trips, kayaking and rock climbing.
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