Physicians at a Kenyan hospital did the wrong brain surgery on two patients. Surgery mix-ups happen more than you might think in the United States.

A brain surgery mix-up in a Kenyan hospital has cast a new spotlight on surgical errors in the United States, which continue to happen despite numerous safeguards.

In late February, two patients awaited operations at Kenyatta National Hospital. One was to have their skull cut open to remove a blood clot in their brain. The other was to undergo a noninvasive procedure to treat swelling in the brain.

It wasn’t until hours into the surgery that doctors realized they had cut into the wrong patient’s head, according to news reports.

The problem in this case was reportedly mixed up identification patient tags.

But there are a number of other things that can go wrong, causing the wrong patient to go under the knife or the wrong body part to be operated on.

And it happens in hospitals all over the world.

In California, 95 surgical mix-ups were reported between 2007 and 2014, although the actual total is likely higher.

Of those incidents, about 62 percent involved operating on the wrong side of a patient’s body, 21 percent were the wrong procedure, 12 percent were the wrong body part, and in two cases, the wrong patient went under the knife.

In Colorado, 107 wrong-site surgeries and 25 wrong-patient surgeries were reported between 2002 and 2008.

Across the United States, 95 incidents were reported last year to The Joint Commission, an independent nonprofit that accredits healthcare organizations.

“It’s important to note that reporting of most sentinel events to The Joint Commission is voluntary and represents only a small proportion of actual events,” Katherine Bronk, a commission spokeswoman, told Healthline.

One estimate, from 2013, of the real prevalence suggested that surgeries on the wrong body part or patient may happen as often as 50 times a week in the United States. That’s largely unchanged from a 2006 estimate that put the figure at about 25 to 52 a week.

In the Kenya case, both patients reportedly survived and are doing well. But a quick review of the scientific literature can turn up a litany of stories with less happy endings.

A young girl was permanently blinded when her healthy eye was removed instead of the cancerous one.

A woman died after undergoing brain surgery instead of jaw surgery.

A man died after his knee was operated on instead of his brain tumor.

Those are extreme examples, but the commission has identified 29 things that can go wrong and lead to potentially disastrous mix-ups.

They boil down to not communicating well enough and not taking enough time to double-check information before the procedure.

To combat those problems, the commission developed a “universal protocol.” It requires doctors to double-check the identity and procedure with all the necessary documents as well as marking the surgical site with permanent markers, and calling a time-out in the operating room just before surgery to verify everything one last time.

The most important step of that protocol may be the first one, especially when it includes getting the information straight from the patient as well as the documents, according to one study.

That report also noted that “marking the operative site gives patients a voice after they are sedated or anesthesia is induced.”

The protocol became mandatory in 2004. But, as the estimates suggest, errors still happen.

The commission says that’s due to the complexities of surgery and to the fact that surgical mistakes don’t have a single cause. Instead, they’re “the result of a cascade of small errors that are able to penetrate organizational defenses.”

It’s also because the window in which errors can occur is wider than the preop through incision time on which the protocol focuses, according to Coleen Smith, RN, director of high reliability initiatives for the commission’s Center for Transforming Healthcare.

The center recommends hospitals also use a Targeted Solutions Tool developed by the center that tries to help them measure performance, identify risks, and find solutions that can be applied to scheduling, preop, and operating room procedures.

As far as what patients can do, listen to make sure nurses and doctors are communicating accurately about the upcoming procedure during handoffs, and ask to make sure the correct surgical site is marked.