How likely is it that you'll catch fire during surgery?

Recently, a jury found that a surgeon performing a cesarean section on a woman was not responsible for the fact that she caught fire during the surgery. Both mother and baby are alive and healthy, but the incident has to be worrying for anyone going into the hospital. How likely is it that you are going to burst into flames on the operating table?

"Virtually all operating room fires ignite on or in the patient." Thus begins the least comforting report on the planet. Most people reading it will focus on the word "in." What could possibly be happening on an operating table to make ones insides burst into flame?

The question is answered in the report from the ECRI Institute, a nonprofit institute that attempts to work out the best practices in medicine. It follows its disturbing first line with an even more disturbing assurance that most fires are "quickly patted out and soon forgotten." One problem is, the surgical environment is full of fuels. Gauze, drapes, the alcohol in degreasers or disinfectants, petroleum based ointments can all catch fire. The patient also supplies a few themselves, in the form of body hair or - and strap in - the gas in their gastrointestinal tract.

The availability of nitrous oxide and the necessity of using oxygen gas in some procedures has given even the slightest fire enough oxygen to flare up quickly. Any leaks in the oxygen supply cause the gas to accumulate, and it's heavier than air. The ECRI report says it tends to accumulate in drape folds and chest cavities. So if your body is open, a gaseous fuel and an oxidizer are in close contact.

There are also more sources of ignition in hospitals now. Past sources included drills or fast-moving cutting implements, that generated high heat. Lasers and fiber optics are more and more used during surgery. Sometimes they're directly hot enough to burn immediately, and sometimes they require time to stay on one area. Even the lights in the operating room, if focused on enough on one particular spot, can cause a spark that sets off a fire in a thin drape, using the available oxygen to spread quickly.

About 550 to 650 surgical fires occur in the United States every year, according to the FDA. Although no agency claims to be able to completely eliminate the possibility of fire, they do recommend ways to reduce the possibility. Surgeries near the face and neck (because of facial hair) and with open chest cavities require extra care. They also recommend using as little oxygen as possible and making sure that alcohol doesn't pool on the skin or on the drapes.

And if that doesn't work - pat like hell.

Image: Sebastian Ritter

Via the FDA and the ECRI Institute.