What is the recommended first step if a diver shows signs of decompression sickness?

The recommended first step for a diver showing signs of decompression sickness is to administer oxygen immediately. This approach is crucial because breathing pure oxygen can significantly help alleviate the symptoms of decompression sickness. The high concentration of oxygen increases the amount of oxygen dissolved in the bloodstream and tissues, which aids in reducing nitrogen bubbles that may have formed due to rapid ascents, thus facilitating their absorption and elimination from the body.

Administering oxygen serves several important functions: it helps improve tissue oxygenation, reduces the risk of further complications, and can assist in mitigating pain associated with the bends. This intervention is usually the first and most critical response while preparing for advanced treatment, such as transport to a hyperbaric chamber.

For effective treatment of decompression sickness, oxygen administration is a vital initial step, prioritizing the safety and well-being of the diver until further medical assistance can be obtained.