MONDAY, May 29, 2006 (HealthDay News) -- Will Cross arrived at Mt. Everest's Camp 4, the last stop before the pinnacle, on the afternoon of May 22, breathing oxygen and trying to stay hydrated.
Two attempts to reach the summit of the world's highest mountain had failed in previous years, and this expedition had already lasted six weeks. In half an hour, Cross and his team were scheduled to go back outdoors and attempt the summit.
Then, the unexpected happened, something that had nothing to do with temperatures or weather.
Cross's blood sugar started to plummet.
"They were the typical symptoms of hypoglycemia. I felt nauseous, dizzy and weak, none of which you want to feel when you're going for the top of the world," said Cross, a 39-year-old former principal and father of six from Pittsburgh who spoke to HealthDay from Kathmandu, Nepal. "Diabetes is not always as predictable as you would like it to be."
Cross, a type 1 diabetic, immediately switched off his insulin pump and ate enough carbs to get him out of danger.
The next day, May 23, at 5:10 a.m. local time, Cross became the first American with diabetes to climb 29,035 feet and stand at the top of the world.
"I felt like a kid in a candy store," he joked. Cross, who has had type 1 diabetes since he was 9 years old, is about as likely to be in a candy store as most folks are to be on Everest.
Cross had hoped to be the first type 1 diabetic to ever scale the world's highest peak, but that honor went to a 49-year-old Austrian man, Geri Winkler, earlier this month.
This type of high-altitude climbing poses brutal challenges for the "ordinary" climber -- freezing temperatures, gale-force winds, ice avalanches.
The climb poses even more life-threatening challenges for a person with diabetes, particularly type 1 diabetes, when the body no longer produces insulin. People with type 1 diabetes must take insulin every day; their lives depend on it. Fortunately, methods of delivering insulin have progressed from a crude needle injection to pumps. Insulin, too, has improved, and Cross used NovoLog, a rapid-acting insulin. Drug maker Novo Nordisk, the maker of NovoLog, sponsored the expedition.
Such technology was in no small way a factor in Cross's recent achievement.
"Fifty years ago, this would have been inconceivable," said Cathy Nonas, director of the diabetes and obesity programs at North General Hospital in New York City and a certified diabetes educator. "Medicine has gotten better, so has ways to monitor blood sugars and delivery systems for insulin," she added.
On a good day, people with type 1 diabetes face considerable dangers, including hypoglycemia or low blood sugar episodes that could put them in a coma. They're also extra susceptible to frostbite, to bacteria and to dehydration, all of which are risks on Mt. Everest.
Even for those without diabetes, the mountain can prove deadly -- claiming the lives of four climbers this month alone. On May 15, 34-year-old British mountaineer David Sharp died of oxygen deficiency while descending from a solo climb, The Associated Press reported Wednesday. His death has led to controversy, with reports of more than 40 other climbers passing Sharp as he lay dying -- most failing to offer any assistance.
And just last week, three climbers from Brazil, Russia and France died while descending the peak in separate expeditions.
Having twice tried to ascend the mountain, however, Cross was better prepared than ever before.
"I knew that on summit night I would need three-to-four liters of water, and I figured out that every time I changed oxygen tanks, I would drink half a liter of water," he explained. "Last time I did this, I did it with one liter. That wasn't enough. I got so dehydrated I couldn't talk, and my lungs were so dry I was coughing."
Cross also took both an insulin pump and the Flexpen, a prefilled injection device, to give him the most control of his insulin.
"At any time in any camp when I tested and knew that my blood sugar was higher than it should be, I could immediately go to the Flexpen because that would control the sugar faster than the pump," he explained.
One surprise was how much insulin Cross needed. "You can't figure it out beforehand," he said. "There's no other mountain that's that high, so you can only do it while you're climbing." Cross figured that he'd need less insulin the higher he went, but it turned out to be the opposite.
"The reason is because the higher you go, the more stress is on the body, and it reacts just like [it's] a sick day, which you wouldn't expect," Cross said. "I would expect the higher on the mountain I go, the harder I'm working, the less food I'm eating (because it's difficult to eat because you feel nauseous,) that I would need less insulin. That doesn't prove to be the case above 8,000 meters."
The finely tuned calibrations any type 1 diabetic needs became even more intricate and involved the higher Cross climbed.
Hypoglycemia was also a big concern. "When you're exercising in that kind of really intensive way, you need to be able to give yourself enough insulin to keep you going but not enough to bring the blood sugars too low," Nonas said. "You need to have a sense of how much energy you're going to be spending, differences in weather and how that's going to affect blood sugar."
Cross was also the first American and the first person with diabetes in the world to walk to the North and South Poles and to climb the highest peak on each continent, an odyssey known as the NovoLog Peaks and Poles Challenge.
His trek to the North Pole started in Russia. Now he'd like to travel there from Canada, a longer, 60-day journey.
"That would allow me to demonstrate that diabetes wouldn't have to limit your life," Cross said.
More information
There's much more about diabetes at the American Diabetes Association.
