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A Little Detail

Text By Gary Rose, M.D., FACS

I TAKE A GIANT STRIDE off the back of the boat and splash into a cascade of tingling, magical bubbles. The sea’s embrace is chilly; I can feel the 74˚F water through my 5 mm wetsuit and thick 4 mm hood. My vision clears as the multitude of entry bubbles disperse.
I begin my descent following the divemaster and feel a slight ache in both ears. As I have done on thousands of previous dives, I perform a Valsalva maneuver, gently blowing and pinching my nose to equalize the pressure in both eardrums and middle ears. The ache in my ears always disappears after this maneuver, but it didn’t this time. I applied pressure a little more forcefully in my pinched nose, and my ears popped, alerting me to the pressure equalization.
Be sure to vent your hood when equalizing to allow water into the external auditory canal to transmit the increasing water pressure to the outside eardrum surface.  
Photo: Stephen Frink
I continued my descent into darker blue water, adjusting the settings of my underwater camera and strobes. My left ear started to ache again, and the pain got worse as I descended farther. It was much worse than the usual ache, so I ascended a little and performed another Valsalva maneuver, and again the pain eased. After descending again, it got much worse, and I was in agony. On a scale of one to 10, the pain was a definite nine. I decided to end my dive. The pain in my left ear disappeared as I ascended. I inflated my surface marker buoy, ascended to 15 feet, completed my safety stop as per dive protocol, and then climbed the ladder onto the boat.

Once on deck and with my dive gear secured against the rolling winter seas, I pulled off my thick hood and was immediately shocked when I discovered that I could not hear anything in my left ear. The next discovery was worse. The deckhand looked at me, his eyes open wide. He pointed at me and said, “Doc, you are bleeding really badly out of your left ear.” I didn’t understand. I had cleared my ears normally, and I stopped my dive when the pain in my ear kept getting worse and performed a safe ascent. So what happened?

In all dive certification courses, no matter the dive training agency, new divers learn about ear barotrauma and how important it is to equalize the pressure on both sides of the eardrum. Middle-ear barotrauma occurs when the pressure in the middle ear cannot equalize with the external water pressure (hydrostatic pressure), and the injury can result in a ruptured eardrum.
Another ear-pressure problem can happen when something — such as earplugs — obstructs the normal ingress and egress of water within the external auditory canal.1 Divers should have learned in their training not to wear them. Earplugs or other blockages can cause an unopposed increase in middle-ear pressure during descent. Blocking the ingress of water into the external auditory canal prevents transmission of the increasing water pressure to the outside eardrum surface. Any blockage can prevent a diver from equalizing the pressure across the eardrum, which can result in pain, external-ear barotrauma, and possible eardrum rupture.

Some divers are prone to earwax buildup, which can block the external ear canal and result in the same issues as using earplugs. This condition is rare and usually of genetic origin.
Returning to my incident, I went straight from the dive boat to an otolaryngologist (ear doctor), who proceeded to painfully suction out the blood filling my ear canal so he could get a better view of my eardrum. We both suspected that I had ruptured it based on the bleeding and hearing loss. It was an excruciating 15 minutes that should have been painless.

Once he removed all the blood, we were both shocked when I exclaimed, “I can hear perfectly!” We were equally happy when he told me that my eardrum looked normal. He then described the mess in my ear canal. I had a hematoma (blood clot) under the skin that lined the canal, and it was located immediately on top of the underlying bone, which caused my extreme pain during the dive. The hematoma ruptured while I was ascending, which instantly relieved the pressure on the bone — the cause of the pain — and resulted in copious bleeding and obstructive hearing loss.

How did I end up with the hematoma? It was a coldwater day for a South Floridian, which is why I chose to wear a thicker wetsuit and hood, which are always stiff. When I descended, I performed the usual Valsalva to successfully clear my ears, but I failed to vent my hood to allow water in as I descended farther. A thick hood acts like an earplug or any canal blockage, so the hydrostatic pressure at depth did not enter my ear canal.

The rest of my circulatory system experienced and transmitted the increased pressure. Due to my blocked and not equalized external ear canal’s negative relative pressure, the tiny capillaries just beneath the thin layer of skin ruptured, causing an expanding hematoma. This skin layer is directly adherent to the underlying temporal bone, which accounts for the pressure that caused the excruciating pain. Because I continued with the dive, the hematoma kept expanding under the ear canal lining until it ruptured.2

Even after 50 years of diving and being a scuba instructor, I failed to vent my hood. The little details we sometimes overlook can transform what should be a wonderful day of diving into a painful and unpleasant experience.

References
1. Glazer TA, Telian SA. Otologic Hazards Related to Scuba Diving. Sports Health: A Multidisciplinary Approach 2016; 8(2):140–44.
2. Nofz L, Porrett J, Yii N, De Alwis N. Diving-Related Otological Injuries: Initial Assessment and Management. Australian Journal of General Practice 2020; 49(8):500–504.

© Alert Diver — Q2 2022

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