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What is a waterspout? -

A waterspout, believed by experts to be the cause of Mike Lynch's yacht sinking, is a rotating column of air with similar characteristics to a land tornado but which occurs over a body of water.

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Autopsy results -

Autopsy results from four of the seven victims who died when the luxury yacht sank in a storm in Italy showed they died of “dry drowning."

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Also known as "atypical drowning" -

"Dry drowning" is also known as "atypical drowning." The victims were found to have no water in their lungs, tracheas, or stomachs.

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"Dry drowning" isn't a medically accepted term -

"Dry drowning" isn't a medically accepted condition, but the terms "secondary drowning" or "delayed drowning" are sometimes used to describe patients whose condition worsened after a near-drowning incident.

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An air bubble in the cabin? -

According to local media, the first four victims likely found an air pocket in the cabin where five bodies were discovered. They used up the oxygen, and as carbon dioxide levels rose the air turned toxic, leading to their deaths.

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Further evidence suggests "dry drowning" -

The victims of the yacht sinking were scanned for physical injuries that could have contributed to their deaths, but none were found.

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What is drowning? -

Drowning is defined as suffocation by immersion in a liquid, usually water.

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All drowning events require exposure to water -

If you are struggling underwater and are unable to come up for air, you will experience a reflex called a laryngeal spasm.

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Laryngeal spasm -

The laryngeal spasm closes off the airway, meaning you can no longer breathe.

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Laryngeal spasm -

When the airway is closed, and no water goes into the lungs, this is technically "dry drowning." Death or injury may happen from the lack of air and asphyxiation.

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Does secondary drowning exist? -

Secondary drowning is also known as a secondary injury from a near-drowning event. It most often happens when water gets into the airway.

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Secondary drowning -

Secondary drowning occurs when you inhale a lot of water before the laryngeal spasm clamps your airway shut.

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The dangers of inhaling water -

Inhaling too much water can cause lung damage and breathing problems that become a cause for concern six to 12 hours later.

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Pulmonary edema -

Pulmonary edema is one of the most serious conditions you can get from ingesting water into your lungs. When the fluid starts accumulating, it causes swelling, and your lungs stop functioning correctly.

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Pulmonary edema -

Symptoms of pulmonary edema include trouble breathing, shortness of breath, and chest tightness. The fluid in the airways is causing you to drown, even though you're not in the water.

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Signs and symptoms -

The signs and symptoms of secondary drowning are similar to those of traditional drowning. However, coughing after jumping in a pool doesn’t necessarily mean you’re at risk of secondary drowning the next day.

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Symptoms could show up -

If you have a near-drowning experience, symptoms can show up after you've left the water. Twelve hours later, you might start to experience breathing problems due to swelling of your lungs from inhaled water.

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Speak to a doctor -

If you have had a near-drowning experience, it's best to get checked out by a healthcare professional to make sure your lungs aren't damaged.

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Warning signs -

If you experience a heavy, persistent cough or shortness of breath and trouble breathing, contact a doctor straight away.

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Warning signs -

Contact a doctor immediately if you notice a change in skin color, develop a high fever, lose consciousness, or experience vomiting or foaming at the mouth, as these may indicate an infection or vascular breakdown.

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Asthmatics or those with a history of lung disease -

If you have asthma, a history of lung disease, or a history of smoking, pulmonary edema symptoms may develop more quickly.

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When to take kids to the doctor -

If your child was submerged underwater, it's best to have them examined and monitored by a physician.

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Children and drowning -

Drowning and near-drowning incidents are leading causes of death in children. Drowning can occur in just a few minutes, even in water as shallow as one inch (2.5 cm).

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How can you prevent drowning or near-drowning incidents involving kids? -

You can prevent children from drowning by always watching them closely when they're in or near the water.

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Know first aid -

It's incredibly helpful to learn basic swimming skills and CPR.

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Pay attention to safety warnings -

If a beach or pool has "no swimming" signs, take them seriously—no matter how much of a strong swimmer you think you are.

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Don't overestimate swimming abilities -

Adults tend to overestimate their swimming abilities, which could increase the likelihood of accidents or drowning, especially in freshwater environments.

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Wear a life jacket -

Always wear a life jacket on a boat, as even the strongest swimmers have drowned or needed to be rescued because they were overcome by the water.

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Swim parallel to the shore -

According to the United States Lifesaving Association, around 100 people drown from rip currents along US beaches each year. If you find yourself caught in a rip current, stay calm and swim parallel to the shore.

Sources: (CNN) (Cleveland Clinic) (Euronews) (United States Lifesaving Association)

See also: The most mysterious shipwrecks in history

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