What if we could breathe underwater?

Swimming accidents - This happens when you die by drowning

What causes swimming accidents?

Non-swimmers who have an accident. People who overestimate their strength. A heart attack in the middle of the lake - there are many reasons why people drown while swimming or bathing. Not infrequently, cockiness, alcohol or drugs are also involved.

How long can people stay underwater?

If you keep your head under water, you don't have to drown - after all, people can dive very consciously. How long a single person can withstand under water cannot be fixed to a certain value, explains Hanno Thomas, medical advisor at the German Life-Saving Society (DLRG).

Because that depends on various factors: Healthy people with a lot of training and at rest can withstand it longer than a wildly kicking person in panic and in poor physical condition. But whether after just one minute or, as with absolute professionals, after ten minutes: At some point the carbon dioxide concentration in the blood is too high. The body signals that breathing is appropriate again. The urge to take a breath then increases.

What happens in the body when drowning?

Who drowns suffocates. It works like this: When water gets into the airways, the glottis in the larynx cramps. "A single drop can trigger this," explains Thomas. Glottic cramp is actually intended as a protective mechanism; it is supposed to prevent fluid from getting into the lungs when swallowed, for example. The result of the spasm: You can no longer breathe. Not even if you are brought to the surface at that moment. Because the cramp in the larynx - just like a cramp in the leg - cannot be actively resolved.

The lack of oxygen then causes the drowning people to pass out. “The first brain cells die after three to five minutes,” says Thomas. The result is damage to the brain and other organs such as the lungs.

For most people, glottis spasm does not resolve during drowning. At about ten to fifteen percent, yes. Then when you inhale, water enters your lungs. In the past, a distinction was therefore made between “wet” and “dry” drowning. So: was there a lot of water in the lungs or not? But this distinction doesn't really make sense, says Thomas: "Because the lack of oxygen is crucial."

Why can people "drown" even on dry land?

If water gets into the lungs, the alveoli can stick together. This effect is intensified by the lack of oxygen. Then the oxygen exchange no longer works properly. However, this does not have to be noticeable immediately, it can also occur hours later. Even if a rescued person has spat out water and looks reasonably fit again, he should still be observed 24 hours in the hospital, says Thomas.

Children are at greater risk. Not because the process has a stronger effect on them, but because they play with water more often and more wildly and have fewer reserves against a lack of oxygen. “It is difficult for children to save themselves. The smaller they are, the larger their head is relative to their body size, which they can then no longer get above the surface of the water, ”says Thomas. If parents are inattentive for just a few seconds, it can be dangerous, warns the DLRG expert.

Does it make a difference whether someone drowns in fresh or salt water?

In practical terms: not really. It is true that salt water contains ions that cause the surrounding cells to pump more water into the lungs. But for the drowning person the difference is minimal, because: the lack of oxygen is the decisive factor.

What role does the water temperature play?

The water temperature can actually make a difference. "With cold water, the oxygen demand of the brain and organs decreases by six percent with every degree." The chance of not suffering any consequential damage is then greater. There are cases of children who could be resuscitated after almost an hour at a water temperature of five degrees. At the same time, however, the risk of cooling down is greater in cold water. This can also cause organ damage. But the same applies here: Ultimately, the decisive factor is the time under water without oxygen.

By Anna Schughart / RND