"That case was not unusual," he said. "You get hit in just the right spot and the right time."
ABCNews.com reached out to O’Brien through his PBS publicist Anne Bell. She said he’d had numerous press requests for interviews but "he wants to stay quiet on the matter."
Jahanhir, who has not treated O’Brien, said that immediate medical attention is always required in cases of acute compartment syndrome.
"What probably happened [in O’Brien’s case] was that it probably hurt, but a man sucks it up and moves on. He delayed and delayed and the arm continued to swell. It’s like in science, when you put a balloon in a Coke bottle and blow up the balloon. The bottle doesn’t expand and that happens to the fascia. They don’t expand. A lot of people think that you lose your pulse, but you can get compartment syndrome and still have a pulse,” said Jahangir. But once you exceed the capillary pressure and the muscles and nerves no longer get oxygen, they will die."
Symptoms include “five Ps,” according to Jahangir, but the most important ones for laymen to know are paresthesia or numbness, “big pain that is out of proportion … beyond how you expect it to hurt” and pain with passive motions, when moving your fingers, for example.
"Go to the emergency room if you get swelling and the arm isn’t right," he said. “These are things you should not ignore."
In O’Brien's case, the award-winning journalist nearly lost his life.
"It was getting real,” he wrote. "Of course I wasn’t awake for the action but I was told later that things tanked even further once I was on the table. And when I lost blood pressure during the surgery due to the complications of compartment syndrome, the doctor made a real-time call and amputated my arm just above the elbow. He later told me it all boiled down to a choice .. between a life and a limb."