Scuba diving and overexpansion injuries (According to a scuba instructor)

When scuba diving you can end up with an overexpansion injury if you are not careful and break the number one rule of scuba, which is DO NOT HOLD YOUR BREATH WHILE DIVING! In this article we’ll discuss how overexpansion inquires occur when breath holding, what types of expansion injuries there are and how to treat them. See you below…

Photo of a scuba diver swimming up to the surface. — If we are not careful we can end up with an overexpansion injury while scuba diving. (Photo courtesy of scubadiving.com)

Cause

As we have discussed in the various past Scuba Tips, Boyle’s Law plays a pretty important part of diving. What we learned from Boyle is that when you increase the pressure on a gas, it’s volume will decrease. The inverse is also true, that when you decrease pressure on a gas, its volume will increase.

Diagram of Boyle's Law. — Boyle’s Law states that volume will increase with the decrease of pressure.

Now where do we find air in our body? Yes, the lungs. We have a right and left lung (bronchi). Inside each lung are branches that end with little sacks of air called alveoli.

Diagram of interior of lungs. — Within our lungs are tiny air sacks called alveoli (Photo courtesy of sciencephotogallery.com)

Our lungs can hold a lot of air, up to 8lbs! If we take a breath underwater and hold it and then start to ascend, the air in our lungs will expand due to Boyle’s Law and the decrease of pressure. If we do not exhale, that air will continue to expand until the the alveoli reach their breaking point and rupture.

Photo of different colored balloons. — Just like a balloon can pop if overfilled, so too can your alveoli if you hold your breath on scuba and ascend.

Injuries

Once the alveoli rupture, air escapes from our lungs into your body. Depending on where the escaped air travels, you can end up with several different types of injuries as listed below.

Mediastinal Emphysema

Mediastinal emphysema occurs when escaped air from the ruptured alveoli moves into the chest cavity. This can cause sternum pain, difficulty breathing, swelling and possible lung collapse.

Pneumothorax

Pneumothorax is the lung collapse mentioned above. This occurs when the air escaped from your ruptured alveoli moves into your chest cavity, between the lungs and the chest wall, and pushes in on the outside of the lung. This can cause chest discomfort and difficulty breathing.

Subcutaneous Emphysema

Subcutaneous emphysema occurs when the the air escaped from your ruptured alveoli travels up the chest wall to under the skin of the neck. This can cause voice changes, crackling under the skin of your neck, a rash and difficulty swallowing.

drawing of characters Snap, Crackle and Pop form rice crispy cereal. — If you suffer a subcutaneous emphysema, you may hear crackling under the skin of your neck.

Arterial Gas Embolism

Arterial gas embolism is when the escaped air from your ruptured alveoli causes bubbles to form and enter your bloodstream. These bubbles can then travel to your heart and/or brain. If the bubbles travel to your brain it can mimic a stroke and if they travel to your heart, it can mimic a heart attack. As you probably guessed, this can be fatal!

Treatment

Treatment is the same for all the overexpansion injuries. Administer 100% oxygen and get the injured party to a medical care treatment facility ASAP.

Photo of diver being administered oxygen. — With an overexpansion injury, administer 100% oxygen and get them to a medical care facility.

Prevention

NEVER HOLD YOUR BREATH ON SCUBA!! 100% of over expansion injuries are avoidable, if you follow this #1 rule of scuba diving. That is it. stick to that rule and avoid overexpansion injuries.

Photo of a man holding his breath. — All overexpansion injuries are avoidable if you stick to the golden rule of scuba, do not hold your breath while diving. (Photo courtesy of snopes.com)

Wrapping Things Up

While lung overexpansion can lead to many different injuries, including possibly paralysis and death, it is easy to avoid. Remember the golden rule of scuba and just keep breathing. Scuba injuries are always of concern.

Finally, do yourself a favor and look into diver’s insurance through Divers Alert Network. For a low annual rate, they will have you covered and are an invaluable resource and help for diver injuries.

DAN’s accident insurance is a great way to protect yourself.

If You’re Looking For other Scuba Diving Tips, Check Out The Below.

“How boring would the world be if everywhere and everyone were the same. Safe travels and good adventures.” Scuba Jay

Scuba diving and overexpansion injuries (According to a scuba instructor)

Cause