Diagnostic dilemma: Liquid-nitrogen-infused cocktail popped a man's stomach like a balloon

The patient: A 34-year-old man in Mexico

The symptoms: Within seconds of drinking a "smoky" alcoholic beverage at a bar, the man felt an intense pain in his stomach.

What happened next: The man was admitted to an emergency department. In addition to experiencing abdominal pain, he was sweating profusely and had become lethargic. His vital signs were a cause for concern. He had an abnormally fast heartbeat of 124 beats per minute, compared with a typical resting heart rate of 60 to 100 bpm. He was also breathing faster than normal and had low blood pressure, and his body temperature had dropped to 95.7 degrees Fahrenheit (35.4 degrees Celsius).

The patient reported feeling discomfort and tenderness when the doctors touched his abdomen in four places. This revealed that the pain was widespread rather than localized to one organ as is often the case with conditions like appendicitis.

The man told his doctors that the drink he'd consumed had been infused with liquid nitrogen, and the doctors suspected that the substance ruptured the man's stomach. When liquid nitrogen warms and converts to a gas, it expands in volume by roughly 700 times. Owing to the enormous difference in temperature between the liquid, at minus 351 F (minus 196 C), and the man's body, the substance could have rapidly swelled into a gas, the doctors wrote in a report of the man's case, and thus popped the stomach like an overinflated balloon.

To assess if there was a perforation in the man's stomach, the doctors listened for signs of air while tapping on his abdomen. Some areas of the abdomen, such as the stomach, normally contain air and produce a high-pitched, "tympanic" sound when tapped. By contrast, more solid or liquid-containing organs, like the liver sitting on top of the stomach, produce a low-pitched, "dull" sound. In this patient, however, the entire abdomen was tympanic, including the region above the stomach.

The diagnosis: Next, the doctors observed the patient's soft tissue using CT scans. From those scans, they discovered a layer of trapped nitrogen gas in the patient's abdomen, just above his stomach and below his lungs — a condition known as pneumoperitoneum. This confirmed that the gas had ruptured the man's stomach and collected above it.

The treatment: The doctors made a small, keyhole incision in the patient's abdomen that released the trapped nitrogen gas. They then inserted a laparoscope — a thin tube with a camera — through the key-hole and into the stomach to find and repair the perforation. Finally, they sutured and sealed the 1.2-inch-wide (3 centimeters) hole, using a piece of fatty tissue from elsewhere in the man's abdomen.

The patient made a quick recovery and was discharged three days later, after he demonstrated he could tolerate a liquid diet, the doctors noted in the report.

What makes the case unique: Besides bursting the stomach, liquid nitrogen that gets consumed before it completely evaporates from food and drink can cause permanent cold burns in the body, as the substance freezes water within human cells and damages tissue.

Luckily, the patient did not experience any cold burns in his mouth, esophagus or stomach. The doctors believed this was thanks to the "Leidenfrost effect," a physical phenomenon that describes how a liquid behaves when it meets a surface substantially warmer than its boiling point. The outermost layer of the liquid instantly vaporizes, temporarily shielding the warm surface (in this case, human tissue) from the remaining cold liquid. This insulating gas layer may explain why the liquid nitrogen didn't burn the man while passing through his gullet.

Liquid nitrogen is often used in food preparation. For instance, flash-freezing meat with this substance preserves its protein structure and locks in moisture more efficiently than other freezing methods do. It can also preserve fats in seafood and help it retain its flavor. However, by the time these food items hit the dinner table, they are safe to consume because the nitrogen has completely bubbled off.

Garnishing food and drink with liquid nitrogen for its smoky, theatrical appearance can be dangerous if impatient gourmands consume those items before the liquid has completely vaporized. As such, it's best to wait until the cloud dissipates. Often liquid nitrogen is used to create a smoke illusion near food, but not within it, minimizing the risk of injury.

For more intriguing medical cases, check out our Diagnostic Dilemma archives.