Pulmonary Barotrauma in a BUD/S Candidate Following Shallow Dives Using the MK 25 Rebreather.

The article focuses on pulmonary barotrauma as a common diving injury among Basic Underwater Demolition/SEAL (BUD/S) candidates, illustrated by a case of a 26-year-old U.S. Navy Ensign who developed pulmonary hemorrhage and pneumatoceles after shallow dives using the MK-25 100% oxygen rebreather. Pulmonary barotrauma typically results from breath-holding on ascent, causing alveolar rupture and potential complications such as arterial gas embolism. The U.S. Navy employs thorough medical screening, including chest radiographs and high-resolution chest CT with inspiratory and expiratory sequences, to evaluate lung injury and fitness to dive, with multidisciplinary medical teams overseeing return-to-duty decisions. Adequate training and pre-dive infection assessment are emphasized to reduce barotrauma risk, and waivers may be granted for return to training following complete resolution of lung injury.