Middle Ear Barotrauma

Dibujo que muestra las principales partes del oído

Barotrauma refers to injuries caused to our body by volumetric variations of gases due to rapid changes in environmental pressure.

Any hollow organ containing gas is susceptible to barotrauma; thus, barotrauma can occur in the ears, paranasal sinuses, teeth with crowns, the digestive system, and the lungs (pulmonary overpressure syndrome).

Middle ear barotrauma is the most common injury in diving. It can be said that practically every diver experiences it to some extent at some point.

Why Middle Ear Barotrauma Occurs

It occurs due to the pressure difference generated during immersion between the middle ear and the exterior, due to a failure of compensation mechanisms, which primarily depend on the Eustachian tube.

Buceador en apnea realizando un descensoMiddle ear barotrauma most commonly occurs during descent, when the environmental pressure increases. Thus, a relative negative pressure is generated within the ear that must be compensated for, which is generally achieved through voluntary maneuvers that force the opening of the Eustachian tube, such as the Valsalva maneuver or the Frenzel maneuver. If this pressure imbalance is not well compensated for, it can lead to barotrauma through an implosive mechanism.

Barotrauma de oído medio. Buceadores con equipo autónomo en la fase de ascenso o emersión.

Although less common, barotrauma can also occur during ascent when the environmental pressure decreases again. The volume of air contained in the ear increases, and typically exits through the Eustachian tube passively without causing any discomfort. However, if there is difficulty in opening the Eustachian tube, barotrauma can occur through an explosive mechanism.

There are various factors that can predispose to experiencing middle ear barotrauma during a dive: having a constitutionally narrow or angled Eustachian tube, suffering from an inflammatory process – such as a cold or allergy – of the upper respiratory tract at the time of immersion, or descending or ascending too quickly.

Imagen de perforación en membrana timpánica

 

Symptoms of Middle Ear Barotrauma

The symptoms that may occur when experiencing acute middle ear barotrauma include: otalgia or ear pain, hipoacusia or hearing loss, tinnitus or ear noises, vertigo or dizziness with a spinning sensation, otorrhagia or bleeding from the ear, and a sensation of air escaping from the ear, especially when blowing the nose or performing the Valsalva maneuver. Symptoms usually appear during the dive or shortly thereafter, and their intensity will depend on the severity of the injury, which can range from mild congestion of the tympanic membrane (grade I) to its rupture or perforation (grade V).

In addition to acute barotraumas, which are well known, there are chronic middle ear disbarisms that occur in individuals with borderline Eustachian tube permeability. Initially, this may not cause any discomfort when not diving and may even allow them to equalize during dives. However, with successive dives or repeated dives over time, microbarotraumas occur in the middle ear, which can eventually produce symptoms similar to those described in acute barotraumas.

When middle ear barotrauma occurs, it is necessary to suspend underwater activities for a variable period of time, depending on the severity of the injury, until complete recovery. Most often, medical treatment will be advised (anti-inflammatories, decongestants, antibiotics, etc.), and in some cases, surgical treatment may be necessary (drainage, closure of the perforation, etc.). With appropriate treatment, most cases resolve without sequelae.