Page 55 - JSOM Summer 2025

approximately 40–60 minutes per dive. They remained well the TM and lining of the middle ear to first expand, then leak,
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within no-decompression limits. Approximately 30 minutes and ultimately rupture. In these cases, pain is the primary pre-
after the day’s second dive, one of the divers operating on a senting symptom of a middle-ear squeeze. A more ominous
small boat approximately 2 miles from the ship began to feel sign in this case is when the pain becomes so severe and sud-
ill. The diver reported headaches, dizziness, nausea, and confu- denly stops. In this situation, pressure has likely equalized due
sion, which was radioed back to the ship. Surface temperatures to a TM rupture.
were approximately 100°F (37.8°C).
The most common finding and best diagnostic assessment is a
The DMO and dive supervisor immediately started gather- notable history of the symptoms previously mentioned, along
ing information, the boat was recalled, and the hyperbaric with the presence of a hemorrhagic TM upon surfacing. A
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chamber was prepped. The immediate concern was type II thorough history in these cases will likely reveal a history of
(neurogenic) decompression sickness. The patient denied any congestion, allergies, or cold symptoms before diving, result-
paresthesia, vomiting, chest pain, or dyspnea. The diver re- ing in eustachian tube dysfunction and the inability to “clear”
ported a history of migraines with similar features to what she the squeeze. The most effective management of middle ear
was currently experiencing. barotrauma is education and prevention. Frequent clearing
during descent is a necessity for a safe dive. Although it is wise
Upon returning to the boat, a complete neurological examina- to avoid diving operations when congested, decongestants are
tion was completed. A 0.9% normal saline (NS) intravenous often used as a “quick fix” to facilitate clearing, especially if
(IV) line was started, oral rehydration and passive cooling the mission is time sensitive. Following injury, however, treat-
were begun, and the patient took sumatriptan, ibuprofen, ment is centered around pain management and decongestants
and Tylenol. The neurological exam was unchanged from the as necessary. A small-diameter ruptured TM routinely heals
patient’s baseline, and symptoms improved rapidly with the without surgical intervention; otolaryngology referral should
above interventions. It was determined that the patient was be reserved for large-diameter ruptures and prolonged dura-
experiencing migraine headaches likely related to heat exhaus- tion at depth with rupture or delays in the initial evaluation.
tion and dehydration, so there was no need for recompression Antibiotic drops such as non-ototoxic fluoroquinolones may
treatment. The patient was closely monitored for the rest of be indicated when a TM rupture is combined with suspected
the day with continued improvement and returned to diving middle ear contamination OR evidence of infection. 4
operations 48 hours later after being cleared by the DMO.
Sinus Squeeze and Facial Barotrauma
Case Study Summary Sinus squeeze is another common injury among those who
These conditions outlined above are a sample of what medi- dive and can be described as increasing pain and pressure over
cal personnel supporting military or government diving oper- the maxillary or frontal sinuses. While middle ear barotrauma
ations must be prepared to manage. Through military diving occurs in approximately 10% of divers, sinus barotrauma
operations, there is also a concern for type I (musculoskeletal) occurs in less than 1%. Diving should be avoided when an
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decompression sickness (DCS), musculoskeletal injuries, ox- individual has any signs and symptoms of sinus congestion to
ygen toxicity, toxic gas exposure, hypercapnia, aquatic wild- avoid this malady. Management of these symptoms involves
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life-related injuries, and many others. These operations often immediately halting descent and ascending to the depth where
occur in remote or austere environments, days from definitive symptoms resolve. Another common condition is facial baro-
care. Military DMOs must be prepared to manage these con- trauma caused by mask squeeze (as seen in case 2) when a
ditions with minimal to no support, delayed evacuation capa- vacuum effect is caused within the mask during descent due
bilities, and limited supplies. to the increasing pressure and decreasing air volume within
the mask. According to the U.S Navy Diving Manual, looking
up, putting two fingers on the top of the goggles, and exhaling
Discussion
forcefully through the nose can generally equalize the pressure
Injuries or maladies relating to underwater diving range from in a face mask. Goggles that do not cover the nose remove
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mild to life-threatening. the ability to clear mask squeeze and should, therefore, only
be used for surface swimming. Mask squeeze often leads to ec-
Middle Ear Barotrauma chymosis of the face along with subconjunctival hemorrhage.
The most common barotrauma injury is middle ear barotrauma, This generally resolves without treatment; however, severe
which can cause a range from mild hyperemia to ruptured tym- cases may necessitate an ophthalmology consult.
panic membrane (TM). Occurring primarily during descent, this
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phenomenon occurs when the ambient pressure exceeds that of Pulmonary Overinflation Syndrome
the middle ear. This increasing pressure forces the TM inward, Less common but more severe injuries fall under the umbrella
initially equalizing the pressure by compressing the middle ear of decompression illness (DCI). DCI is further subclassified
gas out via the eustachian tube. This is commonly referred to as into pulmonary overinflation syndrome (POIS) and DCS.
a middle ear squeeze. The best way to eliminate a squeeze is to POIS is best understood during diving by applying Boyle’s law,
stop descending, squeeze the nose, and Valsalva; this forces the as this describes how water pressure affects the lungs. As a
eustachian tube open, allowing pressure to equalize. diver descends, water pressure increases, causing the air within
the lungs to be compressed and occupy a smaller volume. As a
In those with middle ear dysfunction or in those who descend diver ascends, water pressure decreases, causing the air within
too fast without equalizing often, the stretching capability of the lungs to expand and occupy a larger volume. Based on this
the TM is limited. At a certain point, the middle ear pressure phenomenon, if a diver holds their breath during ascent, the
exceeds the ambient pressure, which creates a vacuum in the lungs will continue to over-expand until they burst. As a re-
middle ear. This negative pressure results in the vasculature of sult, POIS almost always occurs during the ascent portion of a

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