According to the Associated Press, Cleveland Browns rookie linebacker Barkevious Mingo will remain hospitalized at The Cleveland Clinic for at least one more night as he continues to recover from a bruised lung. He sustained the injury during Thursday's preseason matchup against the Detroit Lions.
Also referred to by the medical community as a "pulmonary contusion," a bruised lung can range from very minor to very serious.
Even though—according to Cleveland.com's Mary Kay Cabot—Mingo "felt great Friday and wanted to go home," it should come as no surprise that doctors wanted to watch him for another night. A brief overview of pulmonary physiology and the pulmonary contusion itself explains why.
In the most basic sense, the lungs serve to bring in oxygen and breathe out carbon dioxide. To do this, air enters the mouth or nose and travels down the single trachea before splitting into smaller and smaller tubes—think branches on a tree.
At the end of the smallest branches are alveoli—or tiny air sacs. Each alveolus is surrounded by tiny blood vessels called capillaries, and there are millions and millions of alveoli in each lung.
Alveoli are extremely small. Their walls are also very thin—so much so that oxygen actually flows from the air within an alveolus through its wall and into the surrounding capillaries. The capillaries then deliver the oxygenated blood to the heart, and the heart pumps it out to the rest of the body.
Alveoli also allow for the elimination of carbon dioxide from the blood stream. The idea is essentially the same but in reserve—carbon dioxide flows out of the blood stream and into the alveoli. It is then breathed out to the outside world during exhalation.
Unfortunately, countless different diseases and medical conditions can offset this balance. That's where Mingo's pulmonary contusion comes in.
Presumably, at some point during Thursday's preseason game, Mingo received a direct blow to the chest of sufficient force to cause the injury. The hit sent a shockwave through his chest, tearing alveolar walls within the lung as well as capillaries and other tissues surrounding them.
Broken capillaries can bleed into lung tissue, but they can also bleed into alveoli themselves, transforming them from air-filled to blood-filled sacs. Blood-filled alveoli cannot participate in air exchange, decreasing the amount of oxygen delivered to the body.
Injured lung tissue also swells up during a pulmonary contusion, sometimes leading to further alveolar collapse.
If enough alveoli collapse—or fill with blood or other fluid—serious respiratory problems can surface. In the worst-case scenario, the life-threatening Acute Respiratory Distress Syndrome (ARDS) develops—think massive, widespread alveolar filling or collapse.
On the other hand, small contusions may produce no symptoms at all.
The problem with pulmonary contusions? They can get worse before they get better, as swelling takes time to build up. Usually, it reaches its peak about a day or two after the injury, but it can also develop somewhat unpredictably.
It is also worth nothing that pulmonary contusions do not occur frequently in football. Cabot writes:
"I played football through college, and I've never heard of any football player having this,'' said Clark Fuller, Director of Thoracic Surgery at Saint John's Health Center in Santa Monica, Calif., who hasn't treated Mingo. "Usually the only people I've treated with this were bullriders. It takes a really big whack to bruise a lung. It's hard to do. You've got to really get hit."
The injury somewhat resembles Ben Roethlisberger's incredibly rare and dangerous first rib dislocation, but it is also possible minor pulmonary contusions are very frequent but go unnoticed and undiagnosed.
Thankfully, it seems like Mingo has done well thus far, and the thoughts of the entire football community surely remain with him as he continues to recover.
In most minor cases, pulmonary contusions heal on their own over the course of a week or two, but it could take up to three or more to return to entirely normal function, depending on the severity and the presence of other injuries.
That said, until his oxygen levels, breathing rate and overall clinical status remain improved and stable, it is appropriate to proceed with continued observation and supportive care—at least from an outsider's 50,000-foot-view perspective. It also makes sense to bring him back slowly, as further lung injury could prove catastrophic.
After all, while there is no reason to think serious complications have occurred or will, medicine is just as much about keeping an eye out for the serious as it is treating the less so.
Dr. Dave is a resident physician at the University of Washington with plans to pursue fellowship training in Primary Care Sports Medicine. Medical information discussed above is based on his own knowledge.