As the water pressure lowers on ascent the nitrogen bubbles come out and form gas bubbles within the body. As well as being painful, they are dangerous. The gas bubbles were formed at the greater pressure of depth, and expand as you ascend into the lower pressure. The body will naturally expel the excess gas, but it can only do it at a certain rate. Those expanding gas bubbles can put bubbles in the blood, as well as body tissue. The pain can be so brutal that a victim will literally be doubled up in agony.
In a soda can the bubbles will form out of the depressurized liquid. With a diver, nitrogen bubbles form in the blood. This can seriously interrupt natural blood flow. The maximum really for most snorkelers would be a round 5 meters. Now, the shallowest known and recorded case of the bends was 3 meters in a study but they were all scuba divers who spent time in the water breathing compressed air. A key component of getting the bends is taking on oxygen from a compressed air cylinder.
Each gulp of oxygen was torture — like sucking on an incredibly harsh cigarette. By the end of the first day, I was so tired and in so much pain, I couldn't imagine how I was going to cope with the next five days. For the first few nights, the paralysis would reappear — first in my knees, then my arms. It was the tissue reacting to receiving oxygen.
I cried a lot, which is a common side-effect of the type of bends I had. But I didn't ring my family until the treatment had finished. At first the hospital couldn't tell me whether I'd be left with any permanent nervous system damage.
I didn't want to hear my mum's voice until I knew the outcome. On the final day, I was told I would make a full recovery. The bubbles had gone — I was like flat champagne.
I fell apart the minute I spoke to Mum. She was furious I hadn't told her and immediately booked flights to see me. By the time she arrived, my despair at being so ill had been replaced by anger.
The higher oxygen content of nitrox comes with an increased risk of developing oxygen toxicity if safe depth limit is exceeded. Note: Diving enriched air requires special training. Contact your local dive center or resort to learn more. While individual susceptibility to DCS may vary, every diver can reduce their risk of decompression sickness by ascending slowly from every dive and following recreational diving guidelines. Postdive Air Travel Flying after diving increases decompression stress because the pressure in an aircraft cabin is lower than atmospheric pressure on the ground.
The recommended guidelines for flying after diving are as follows: After a single no-decompression dive, a minimum preflight surface interval of 12 hours is suggested. After multiple dives per day, or multiple days of diving, a minimum preflight surface interval of 18 hours is suggested. After dives requiring decompression stops, a preflight surface interval substantially longer than 24 hours is considered prudent. Medical Emergencies Abroad.
Scuba injuries may be mild. But in some cases, they can cause serious problems or even death. There are three kinds of injuries from pressure changes when diving: Barotrauma: Tissues near the air-filled spaces of your body—such as your ears, sinuses, dental roots, and lungs—can be damaged if your body can't equalize the pressure between it and the surrounding water.
This kind of injury is called barotrauma. As you descend, water pressure increases, and the volume of air in your body decreases. This can cause problems such as sinus pain or a ruptured eardrum. As you ascend, water pressure decreases, and the air in your lungs expands. This can make the air sacs in your lungs rupture and make it hard for you to breathe. If air bubbles get into an artery, they can cause a blockage that affects your organs.
The blockage is called an arterial gas embolism. Depending on where the bubbles are, you could have a heart attack or a stroke. Decompression sickness: Often called "the bends," decompression sickness happens when a scuba diver ascends too quickly.
Divers breathe compressed air that contains nitrogen. At higher pressure under water, the nitrogen gas goes into the body's tissues. This doesn't cause a problem when a diver is down in the water. And if a diver rises to the surface decompresses at the right rate, the nitrogen can slowly and safely leave the body through the lungs. But if a diver rises too quickly, the nitrogen forms bubbles in the body. This can cause tissue and nerve damage. In extreme cases, it can cause paralysis or death if the bubbles are in the brain.
Nitrogen narcosis: Deep dives can cause so much nitrogen to build up in the brain that you can become confused and act as though you've been drinking alcohol.
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