“While she was physically strong, physiologically she struggled to cope with the thin air,” wrote Cool in an Instagram post. “Her oxygen saturation was worryingly low. At sea level most of us would record a healthy 99/100%, anything lower than 95% and you’d probably find yourself in Casualty, at Camp 2 Victoria registered 28%. That’s nearly dead. We rushed her onto oxygen and dexamethasone, to prevent HAPE, High altitude Pulmonary Edema. It was pretty scary for all of us to say the least.”
Pendleton, who was climbing alongside TV presenter Ben Fogle, revealed that following a “positive and comfortable” day traversing a glacier she began to feel unwell and her body started to “go into shutdown”.
Despite being treated with oxygen it became clear that Pendleton had not had time to make the necessary adjustments to the high altitude and a decision was made that she should abandon the challenge.
“Unfortunately after much deliberation I have decided not to continue my endeavour to summit Mount Everest,” wrote Pendleton on Instagram.
“The weather conditions have offered the possibility of an early summit bid, as a consequence I have been unable to adhere to the prescribed rotation program and keep pace with the team without causing concern regarding my health at the higher camps, due to my lack of adaptation to the extreme altitude.
“I am incredibly disappointed not to complete the challenge and frustrated as I feel in great physical condition and was moving swiftly and efficiently through the icefall and across the glacier, at no point did I feel this was a weakness in the challenge.
“Whilst we were working and moving I was really positive and comfortable. Unfortunately when we were recovering in camp in the afternoon, relaxing with a resting heart rate with a less active breathing pattern, I started to feel quite unwell and felt my body was going into shut down and the oxygen saturation of my blood was very low. So much so that I required a light flow of oxygen that continued throughout the night.
“My condition caused much concern to Kenton and distressed the team. Kenton felt it was perhaps more sensible for me not to continue, for the sake of my health and wellbeing. I took his advice and called an end to my summit bid.”
Despite her experience, Pendleton described the Himalayas as “a magical place” and wished her fellow climbers luck in their continuing bid to finish the climb.
“I am extremely grateful for this opportunity to have experience one of the the most impressive, imposing and challenging environments on the planet, the Himalayas are a magical place I feel honoured to have visited,” she wrote.
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