Why Is Hyperventilating Before Diving Dangerous?

Hyperventilation is a dangerous sign that can lead to shallow water blackout, where a person loses consciousness due to a lack of oxygen in their bloodstream. This is often caused by anxiety or panic attacks, stress, intense physical activity, and certain medical conditions. Hyperventilation before diving is a form of over-breathing that reduces the body’s carbon dioxide content but does not significantly affect oxygen content. If hyperventilated to any significant degree and the diver finds themselves at 20m, they are already at risk of blackout.

Some common causes of hyperventilation include anxiety or panic attacks, stress, intense physical activity, and certain medical conditions. Hyperventilating before diving is dangerous because it can cause breath-hold divers to stay down longer than their oxygen reserves will allow, making them more susceptible to blackout during the dive. Breathholding or purposeful hyperventilation before going underwater is dangerous, occurring in public pools, home pools, and free diving in the ocean.

The problem with hyperventilation is that it doesn’t supersaturate the blood and tissues with oxygen, as previously hypothesized. Instead, it depletes the oxygen in the bloodstream, making the diver more susceptible to blackout. Breath-hold divers who hyperventilate before a dive increase their risk of drowning.

In conclusion, hyperventilation before diving is a dangerous sign that can lead to shallow water blackout, which can be caused by various factors such as anxiety, panic attacks, stress, intense physical activity, and certain medical conditions. It is essential to avoid hyperventilation before diving to ensure safety and prevent potential risks.