Overview: What is barotrauma?
Barotrauma refers to tissue damage that occurs when the gas contained in various body cavities compresses or expands due to a change in ambient pressure. Translated, barotrauma means “pressure injury” (Greek baros = pressure, trauma = injury). Harmful pressure loads occur during diving, air travel, rapid changes in altitude or explosions, among other things. This can affect the ears, lungs, gastrointestinal tract, the part of your face covered by a diving mask or the sinuses.
The ears are most frequently affected by barotrauma. Barotrauma poses the greatest risk to the lungs.
Barotrauma: causes and risk factors
The body can dissipate increased external pressure evenly through the blood and body tissues. For example, you will not feel any pressure build up in your arm when the water pressure increases during diving. Gases, however, as they occur in air-filled cavities in your body, such as inside the lungs, sinuses and middle ear,
but also in the cavity of the diving mask and goggles condense or expand when the external pressure increases or decreases. This change in volume can cause pain and tissue damage.
The strongest barotraumas occur at the beginning of a dive when you descend into deep water. The ambient pressure then rises and deviates from the pressure that prevails in the air-filled cavities of your body. Your body has to compensate for this difference. You create the balance by connecting to the outside, for example via the nasopharynx when you yawn and swallow with your nose held shut. However, if the nose is blocked by a swelling of the mucous membrane, for example due to a cold, equalization is difficult or impossible. If the ambient pressure then rises at greater water depth, a relative negative pressure is created in the body. This can cause your eardrum to burst, for example.
The most common causes of barotrauma are air travel. Whether it occurs depends on the altitude, the type of flight and the passenger. A study of airline passengers found that 20 percent of adults and 40 percent of children had negative pressure in the middle ear after landing and that ten percent of adults and 22 percent of children showed visible signs of damage to the eardrum.
The greatest risk of barotrauma is if you dive despite having a cold or sinusitis. Then your mucous membranes are swollen and the Eustachian tube, which connects the middle ear and throat, is blocked. As a result, you cannot achieve (sufficient) pressure equalization in the ears, sinuses and diving mask. But accidents, ill-fitting diving clothing or defective lung regulators, the use of earplugs and faulty dental fillings are also risk factors for barotraumas.
People who were in the vicinity of an explosion or people buried in an avalanche can also suffer barotrauma.
Symptoms: Depending on the organ affected
Barotrauma can affect different parts of your body and cause a wide range of symptoms, from bleeding into the eye to ruptures in the lungs that can lead to death.
Eye barotrauma
Barotrauma of the eyes occurs when a diver is unable to equalize the pressure between the area behind the diving mask and the surrounding area. He normally manages to equalize by exhaling through his nose into the diving goggles. However, if the nose is blocked due to a cold, for example, the pressure cannot be equalized (completely) and a negative pressure is created in the mask chamber. This exerts tension on the skin of the face and eyes and the mask clings ever more tightly to the face. This can cause bruising and bleeding around the eyes.
The symptoms of barotrauma in the mask area may look dangerous, but in most cases they heal without consequences.
Barotrauma of the skin
If the wetsuit fits poorly and wrinkles, skin may be pressed into the cavities. As a result, blood leaks into the tissue, causing streaky bruising. They heal by themselves over time.
Lung barotrauma
A defective regulator and various diving accidents can cause barotraumas of the lungs. If the regulator is defective, correct pressure equalization is no longer possible. The lungs cannot fill with enough air, which leads to dizziness and even unconsciousness. Accidents can also cause the diver to faint. A diver without consciousness sinks quickly:
- Increasing negative pressure is created in the lungs.
- The pulmonary vessels rupture.
- Blood flows into the lungs.
- The heart does not receive enough oxygen-rich blood.
- Blood pressure drops.
- The ribs break with increasing depth.
- The chest is compressed.
Barotraumas of the lungs are often fatal. For safety reasons, divers should always be accompanied by at least two people. The buddy can then prevent the unconscious person from sinking and slowly bring them to the surface.
Barotrauma of the gastrointestinal tract
Gases in the stomach and large intestine react to external pressure changes. In addition, divers may swallow air if they do not breathe correctly via a regulator or when using ear and sinus pressure equalization techniques. This air expands during ascent and causes bloating, cramps, pain, belching and flatulence. Stomach wall injuries are rare.
Sinus barotrauma
Barotrauma of the sinuses makes itself felt with severe, stabbing pain in the forehead and cheekbone. Normally, the pressure in the paranasal sinuses is equalized automatically via the connection to the nasopharynx. However, if the mucous membranes are swollen and therefore almost impermeable, pressure equalization does not work. Benign tumors, such as polyps, can also prevent it or make it more difficult.
The barotrauma of the paranasal sinuses forces the diver to return to the surface. If the difference in pressure was only slight, the pain usually subsides without complications. In some cases, however, this can also lead to inflammation of the paranasal sinuses.
Ear barotrauma
Barotrauma of the ear can affect the outer, middle and inner ear.
Barotrauma of the outer ear
As water can penetrate through the ear canal to the eardrum, the outer ear is normally always at ambient pressure. However, if a diver uses earplugs unnecessarily, this can prevent pressure equalization in the outer ear. The increasing pressure with increasing diving depth presses the earplugs against the eardrum. This can tear, causing a sharp pain in the ear. There may also be bleeding from the ear. A hood that is too tight can also prevent pressure equalization in the outer ear. Lifting the hood briefly helps here.
Barotrauma of the middle ear
Barotrauma of the middle ear is characterized by dizziness, pain, ringing in the ears and bleeding from the ear. This can lead to infections and inflammation of the middle ear.
If the pressure in the middle ear remains at the level of the surface pressure due to air that has collected there, the diver must equalize the pressure via the Eustachian tube at a depth of two to three meters. This is achieved by holding the nose closed with the fingers and gently pressing air against it. He or she can feel and hear the pressure equalization. If the Eustachian tube is swollen or blocked by mucus and the diver still performs the equalization with high pressure, mucus can be pressed into the middle ear. As a result, capillaries in the mucous membranes may burst. There is even a risk of the eardrum bursting.
Barotrauma of the inner ear
Symptoms of barotrauma of the inner ear are
- Earache
- Hearing problems
- Balance disorders
- Rotational vertigo
- Ear whistles
- Deafness
- Nausea and vomiting
If the symptoms persist after the dive, you should consult an ear, nose and throat specialist immediately.
Although there is no air in the inner ear, a strong pressure wave can cause various degrees of damage, including leakage of the inner ear fluid. Such a pressure wave can occur when the eardrum bursts, for example when someone forces a pressure equalization in a blocked Eustachian tube.
Barotrauma of the teeth
Barotraumas of the teeth occur when cavities form in faulty fillings. This means that the tooth can be pressed in, for example, if it descends too quickly or to a great depth. Toothache gives the diver an indication of this.
Barotrauma: Diagnosis by us
We diagnose barotrauma mainly on the basis of the type of symptoms and in relation to the time of a flight or dive. Depending on the body characteristics, we examine the nasopharynx and the ear, for example, carry out hearing tests and a balance test or, if necessary, perform imaging examinations. Patients with a pulmonary barotrauma, for example, usually require a chest X-ray. Patients with barotrauma of the middle ear or eye may need to undergo a hearing or vision test.
In addition, imaging procedures such as computer tomography and magnetic resonance imaging are used for diagnosis.
Barotrauma: prevention, early detection, prognosis
You can prevent barotrauma during a dive by not diving even if you have a slight cold. Before each dive, test the permeability of the Eustachian tube by pressing air into the blocked nose. Try not to dive despite having a cold by using a nasal decongestant before the dive. This may help you to descend, but as soon as the effect wears off, you are in danger. Do not dive if you suffer from earache, even if it is only mild.
You can prevent barotrauma during a flight by yawning, chewing or swallowing. It is therefore advisable to chew gum or drink something during the landing phase. It is important to start before symptoms occur so that a large pressure difference cannot build up in the first place. It is best to breastfeed or feed a small child. If you have a cold, you should use decongestant nasal spray when taking off and landing.
Early detection of impending barotrauma while diving is possible by listening to your body: If you are unable to equalize your pressure under water, you should abort the dive. This also applies if you feel pain in your ear, stomach or intestines.
Most forms of barotrauma have a good prognosis. In the case of pulmonary barotrauma, it depends on how quickly the diver was able to receive pulmonary medical treatment.
Barotrauma: treatment of the affected area
The treatment of barotrauma depends on which organ is affected. Most problems disappear by themselves. For barotrauma of the nose or ears, you will usually be given painkillers and decongestant medication, such as nasal spray.
Barotrauma of the lung is a medical emergency and often requires intensive care. First of all, the doctor must ensure that vital bodily processes are maintained before he or she can deal with further pressure damage.