MANKATO — These types of mistakes don’t happen often. But if your surgery is the one in 6,000 where it does, you’d probably wish some additional measures had been taken to avoid having a surgical sponge left inside you when it was over.

“One in 6,000 is rare, but it’s one too many,” said Steve Campbell, chief medical officer for patient safety for Mayo Clinic Health System in Mankato. “The consequences of a sponge left behind can be huge.”

In 2009, the Mayo Clinic in Rochester implemented new technology to avoid such mistakes. It’s a simple bar code reader, but the way it is used has the potential to cut down on human error dramatically.

As of last week, that same technology is now being used in Mayo Clinic Health System in Mankato and Mayo Clinic Health System in New Prague.

Here’s how it works:

In surgeries and childbirth, a package of sponges will be used. The wrapped package comes with one bar code, which is scanned at the beginning of a procedure. When the procedure is complete, the sponges — each of which has an individual bar code — are scanned individually to make sure each is accounted for. They’re also counted manually as has always been the case.

The reason for going to a bar-code scanner was simple: safety.

In the Minnesota Department of Health’s most recent annual report of so-called “adverse incidents,” Mayo Clinic Health System in Mankato had just one incident flagged. Campbell said this week that the incident involved what is known as “retention of a foreign object in a patient after surgery or other procedure.”

That case, for which specific details are not releasable, involved a surgical sponge.

“We would hope going forward that we would never have another retained sponge,” Campbell said. “We’ve put in a system that reduces the chances of human error by one more step.”

Susan Pearson, an ear/nose/throat doctor who performs surgeries regularly, said she had reservations at first.

“What concerned me the most was that it would take up a bunch of extra time when they’re scanning them,” she said. “And it really doesn’t.”

Pearson said that use of the bar code scanning system mainly falls to the nurses. So far, she said, she’s seen it in action a handful of times. Nurses, who must count the sponges manually anyway, simply scan them as they’re counting them. The additional time required is negligible.

Pearson said last year, across the state, there were 37 incidents of objects left in patients after surgery. The vast majority were sponges.

With surgeries and technology getting more complex, and with the doctor’s desire to get patients out of surgery as quickly as possible, the stress level during surgery can get high. Plus, the longer a patient is under anesthesia, the more complications can occur. There is plenty of incentive to get things done quickly.

That’s why it’s good, Pearson said, to have that additional check in place to make sure an “adverse incident” doesn’t happen. And she’s been impressed with it so far.

“It is pretty amazing,” she said.

The bar code system is called SurgiCount, and since its debut in 2009 in Rochester, not one sponge has been left in a patient. It has scanned more than 1 million sponges.

“This technology adds a layer of redundancy and takes out the element of human error,” Campbell said.

The plan is to roll it out throughout region in coming weeks. As for other tools used during surgery, the bar code system does not keep track of those. Although Campbell said research is being done to develop a system for that, too.

And as for cost, the bar code system works out to cost about $2 per operation.

“If we prevent one retained sponge, it pays for itself many times over,” he said.