Dive instructors always explain the relationship between pressure and volume to new divers, describing the need to descend slowly and steadily, and to equalize air-spaces early and often. New divers learn this information within the first few minutes of every scuba class, but why? Simply put, because ear barotrauma is the most common dive-related injury. It often relegates divers to land or, sadly, deters potential divers from pursuing the sport at all.
Ear barotrauma is incredibly common, hitting approximately 30 percent of first-time divers. Additionally, around 10 percent of experienced divers have suffered an incident as well. Symptoms can vary from mild to excruciating, with permanent hearing loss in extreme examples.
What is ear barotrauma?
The human ear consists of three main parts: the external, middle and inner ear. The word “barotrauma” stems from the Greek baros, meaning pressure, and trauma, meaning injury. If the ear cannot cope with abrupt pressure changes, a key area of the ear will likely rupture. Diving with a cold or congestion can also cause ear barotrauma.
The outer ear
The auricle, or pinna, of the outer ear — the funnel visible on the outside — is what most of us think of as our “ear.” From here, sound waves funnel down a canal and arrive at the tympanic membrane — the eardrum. The average adult’s ear canal is around one inch long (2.4 cm), and on the other side of the eardrum is the middle ear. Here, three tiny bones conduct the sound into a format that our brains can interpret.
The Eustachian tube
The Eustachian Tube connects the middle ear to the throat. Therefore, its function is crucial to scuba divers. Introducing air into this contracting air space is what equalizes the pressure on the inside of the tympanic membrane with the ambient pressure external to the diver descending through the water column.
The inner ear
Finally, the oval and round windows are within the inner ear. These sensitive membranes are key to the ear’s health. Overzealous equalizing can rupture either, or both, of these tiny areas, leaving the diver with anything from vertigo and vomiting to hearing loss. Consequently, instructors advise students to equalize early and often, gently blowing against pinched nostrils, wiggling the jaw or swallowing.
What causes ear barotrauma?
Cast your mind back to the first section of your Open Water Diver manual. According to Boyle’s Law, as the ambient pressure increases, the volume of the air spaces within your body in contact with that pressure will — if left unattended — decrease. This basic lesson in physics is the core of understanding ear barotrauma, which occurs when increasing ambient pressure during your descent causes the volume of the gas-filled spaces in your ear to shrink. The sensitive membranes and tissue that make up the ear’s key areas become distorted, eventually becoming damaged. This is the most common type of ear barotrauma. Attempting to ascend while diving with a cold, congestion or fading decongestants can cause a “reverse block,” which means gas is unable to escape. This can also cause ear barotrauma.
Types of ear barotrauma
There are various types of ear barotrauma. Each has its own causes and symptoms.
- External ear canal superficial vessel rupture: A rupture of the blood vessels in the external ear. Often a scuba diver may experience small amounts of bleeding from the ear canal.
- Tympanic Membrane (TM) rupture: Perforation of the eardrum. Pain, dizziness and vertigo are common symptoms.
- Inner ear barotrauma: Damage to the round or oval window. A distressing condition that can cause tinnitus, dizziness and vomiting.
- Otitis media: While not strictly a barotrauma, divers can confuse the pain and fluid-loss from a middle-ear infection with a barotrauma.
- Otitis externa: Commonly called “swimmer’s ear,” this is a common condition among scuba divers, especially those who neglect post-dive ear care. Inflammation, pain and swelling of the ear canal are common symptoms.
Crucially, if you experience any of these symptoms, you must stop diving. Diving again will — at best — cause further discomfort and exacerbate the injury or infection. At worst, diving with ear pain may endanger both your health and the rest of your dive team’s safety. Unfortunately, there is no quick fix for most of these issues. Thusly, it’s best to consult a qualified medical professional with knowledge of diving medicine. Alternately, you can access additional resources on ear health at the Divers Alert Network (DAN).
Only your doctor can determine how long you must stay out of the water. However, don’t expect to be in the water again for several days for even minor injuries or infection. For more serious injuries, dry weeks lie ahead.
Avoiding ear barotrauma
No matter what your qualification, experience level, or number of dives, you can’t change the laws of physics. You must go back to basics on every dive.
- Practice on land. Relax before your dive and practice equalizing before getting in the water. While practicing, you should hear a pop, clunk or click indicating your Eustachian tubes are open. If you’re struggling to equalize, tell your buddy and the dive leader because you may need to descend very slowly. If you cannot descend slowly, such as in an area with strong current where you need to get to depth quickly, consider skipping the dive. Don’t force your ears.
- Avoid accessories. Don’t wear earbuds or any accessory that will block the flow of air in the body’s air spaces.
- Don’t dive with a cold or congestion. Mucus in the body’s air spaces can make equalizing a long, protracted and painful affair. Don’t compromise your safety and your buddies’ dive by forcing the issue.
- Avoid decongestants. To avoid missing a dive, some divers with colds or congestion divers pop medications to ease equalization. This is unwise, since these drugs can often wear off mid-dive. Then, as the diver ascends, expanding gas cannot escape. This often leads to a reverse block and injury.
- Avoid milk, tobacco and alcohol. These may irritate your mucus membranes, making equalizing difficult if you are already prone to equalization problems.
- Chew gum. There is some anecdotal evidence that chewing gum between dives may help your ears.
- Equalize early and often. Memorize the mantra of scuba-diving instructors. Begin equalizing before you feel any pain or discomfort. Leave the surface with one hand on your nose, beginning to equalize early in the descent.
- Use the tools at your disposal. If there is a descent line available, use it. And if you have any problems, pause your descent. Take the line for control. Only move deeper in the water column when you have successfully cleared your ears.
- Help your body. Make the initial few feet/meters of your descent feet first. The biggest proportional pressure change occurs during the first 30 feet (10 m). If you’re still struggling to equalize, look up to the surface. Doing so may help extend your Eustachian tubes and help you equalize.
- Learn what works. Everybody has differing physiology, so learn which method of equalization works best for you. Techniques include swallowing, wiggling the jaw, Valsalva, Toynbee, Lowry, Edmonds and Frenzel. Each of these differs slightly in technique, but there is no right or wrong — only what works for you.
- Don’t force it. Sometimes it’s not your day to dive. If you feel pain or discomfort, don’t force your ears and potentially hurt yourself or compromise everybody’s dive.
Ear barotrauma is surprisingly common. So remember to take care of your ears and dive safe and equalize early and often to avoid potential problems. If you do suffer an ear-related problem, abort the dive and seek professional medical advice.