What is the appropriate course of action if the diver experiences a loss of O2 during treatment for less than 15 minutes?

When a diver experiences a loss of oxygen during treatment for less than 15 minutes, the appropriate course of action is to resume treatment immediately at the point of interruption. In hyperbaric medicine, holding off treatment for short durations, especially under 15 minutes, does not typically have significant physiological effects that would necessitate starting over. The body’s response during this brief interruption is generally stable, allowing treatment to continue without requiring a full reset.

Resuming treatment at the point of interruption makes sense because the diver has not accumulated excessive nitrogen or experienced a significant risk factor that would arise from the break. This action allows for the continuation of therapeutic benefits without unnecessary delays or complications.

The other options either suggest unnecessary interventions or could lead to increased risks. For instance, aborting the treatment or switching to ambient air would disrupt the therapeutic process significantly and could delay recovery for the diver. Treating in the chamber after surfacing might also complicate the situation, as the diver would have to face the effects of decompression again, which is counterproductive. Thus, resuming treatment at the point of interruption is the most logical and clinically sound decision in this scenario.