What is the initial treatment for altitude DCS if symptoms resolved before reaching 1 ATA?

The initial treatment for altitude decompression sickness (DCS) when symptoms have resolved before reaching 1 ATA (atmospheric pressure) is the administration of supplemental oxygen for a designated period, typically around two hours. This is important because supplemental oxygen helps to enhance the elimination of nitrogen from the tissues, which is a crucial factor in the resolution of DCS symptoms. By breathing high-flow oxygen, the body can more effectively absorb oxygen and expel nitrogen, thus alleviating the risk of further complications associated with residual nitrogen bubbles in the bloodstream or tissues.

In contrast, immediate hyperbaric oxygen therapy is often reserved for more severe cases of DCS or when symptoms persist, rather than for cases where symptoms have already resolved. Pain relief medication might also be beneficial for managing symptoms associated with DCS, but it does not address the underlying condition of nitrogen bubbles in the body. The option of 'no treatment needed' contradicts the recommended approach of using supplemental oxygen to enhance recovery and monitor for any potential recurrence of symptoms.