An American mountaineer died Wednesday while descending from the summit of Mount Everest, according to the Nepalese company leading the expedition.

Donald Lynn Cash, 55 of Sandy, Utah, fainted due to high altitude sickness after reaching Everest’s summit, according to Pioneer Adventure Pvt. The expedition company said its guides tried to give Cash aid while bringing him down the mountain.

“Our supporting Sherpa Guides did immediate massage, CPR and raised his oxygen pressure to keep him alive,” the company said in a news release. “In that situation, our Sherpa Guides tried to rescue and drag him down towards Camp 4 as quick as they could.”

Cash had collapsed near a portion of the trail called the “Hillary Step,” an elevation of approximately 8,770 meters, according to Pioneer Adventure.

“Despite their best efforts in providing the best guidance, sufficient oxygen supplies and medical support they could not save his life,” the company said.

The cause of death is undetermined at his point. Cash, who is also a grandfather, died after completing his goal of climbing the highest mountain on every continent, his children told CNN affiliate KSL.

“He taught us that nothing was impossible. You can do literally anything. If you can dream it, you can do it,” his daughter Brandalin Cash told KSL.

Cash, who is originally from Ohio, had worked in software sales, according to the station.

Mount Everest’s famed “Hillary Step” location is named after Edmund Hillary, the first climber to successfully reach the mountain’s summit along with Tenzing Norgay in 1953.

Cash’s body will likely remain on Everest, according to KSL.

“The last message he sent to me, he said ‘I feel so blessed to be on the mountain that I read about for the last 40 years,’ ” his son Tanner Cash told the station.