Too much beer and a lake dive proved a nasty combination for a Maine man—but probably not for the reasons you might think. The unidentified man, whose case is described in the Journal of Emergency Medicine, arrived at an emergency room complaining of severe pain in his abdomen after he'd dived off a boat into a lake after a day of drinking. His abdomen was swollen and tender, but the 24-year-old couldn't pee. A catheter soon revealed urine mixed with blood, while a CT scan showed urine was leaking into his abdomen through a hole in the top of his bladder. Even with a full bladder, "drunk people don't always realize they have to pee," which can lead to a traumatic bladder rupture, Dr. Bradley Gill explains, per Live Science. But it was the pressure of the lake dive that dealt the ultimate blow. It was "the equivalent of throwing a water balloon on the sidewalk," Gill says.
He explains that a bladder—which might hold anywhere from 10 to 20 ounces of pee—comes under pressure as it fills, but outside forces cause added pressure. "If you imagine holding a water balloon between your two hands and squeezing it, the part that pushes out between your two hands is going to eventually bubble out and burst," he says. While researchers say most bladder ruptures occur when the bladder is penetrated—say by broken bones—"intraperitoneal" bladder ruptures caused by added pressure occur in up to 40% of cases. Gill cites a common example: a child who avoids using the bathroom during a soccer game, only to be hit in the abdomen by the ball. Luckily, the bladder "has a pretty substantial capacity to recover from injury," Gill says. Doctors were able to stitch up the hole in the 24-year-old's bladder, which should be back to normal within weeks. (We may make better decisions when we have to pee.)