The decomposition that Ralston reportedly observed in his arm during the later days of the entrapment is consistent with this timeline. Tissue deprived of oxygen and blood flow for extended periods undergoes necrosis — cell death that begins at the cellular level and eventually produces visible changes in tissue color, texture, and odor. That he could observe this process while still alive, still thinking clearly enough to make complex decisions, is itself a testament to the remarkable resilience of the human body — and also to the specific physiology of compartmentalization, where the death of tissue below a constriction point does not immediately accelerate the overall systemic failure of the organism above it.
The tourniquet he applied after completing the amputation was essential to his survival in the short term. Applied with skill and the materials available — CamelBak tubing and padding from his biking shorts, according to the accounts — it prevented the blood loss that would otherwise have made the subsequent hike physically impossible. The four-hour window between the amputation and the helicopter pickup was narrow enough that the tourniquet’s effectiveness determined whether the hike and the rescue were possible at all. He managed it.
He lost approximately 25 percent of his blood volume during the entrapment and escape, and approximately 40 pounds of body weight. These figures, reported by his treating physicians, give a concrete measure of the physiological cost of 127 hours in Blue John Canyon. A blood volume loss of 25 percent is in the range classified as Class III hemorrhagic shock in emergency medicine — a condition that typically produces rapid heart rate, decreased blood pressure, and altered mental status, and that requires aggressive intervention to prevent deterioration. That Ralston was able to hike five to seven miles, rappel a cliff, and walk unaided off a helicopter while in or near that physiological state is extraordinary by any medical standard.