For many people who need surgery, their greatest fear is not the surgery itself but the anesthesia -- and the fear that they will wake up during the operation.

Although anesthesia is safer than ever before, some people do become aware during surgery. Now there's a way to help prevent that, reported WNBC-TV in New York.

"It feels like your insides are being ripped out from inside," said Angela Barca, a former nurse who awoke during an emergency Caesarean section when her son was born 17 years ago. "I first of all started to panic. I thought something was very wrong."

"I tried to move, and I couldn't," Barca said. "I tried to move my arms, tried to open my eyes, tried to kick -- do anything I could: scream, talk ... nothing."

That's because patients are often given paralyzing drugs during surgery. And although it is rare, this so-called anesthesia awareness does happen often enough that the accrediting agency for hospitals issued an alert, calling the problem frightening and under-recognized.

"There are people who have estimated that that would work out to be about 100 people per workday in the United States who are having surgery," said Dr. Donald Matthews, of St. Vincent's Hospital in New York.

Part of the problem is that anesthesia is part science and part art.

"It's not like a light switch, where you just turn something on and off," Matthews said. "It's more like a dimmer switch. Where you go from being wide awake to being ... absolutely having no brain activity at all, and the anesthetics can have a person anywhere in that continuum."

To minimize the risk of patients waking up during surgery, anesthesiologists at St. Vincent's have been using something called a BIS monitor. Stick-on forehead electrodes translate brain waves into a number that reflects the depth of the anesthesia.

Knowing doctors will use the BIS monitor during his knee surgery is reassuring to Stanley Vogel.

"That's another layer of protection that would make me feel better, would make me feel much more comfortable that this will not happen," Vogel said.

Most people with anesthesia awareness don't actually wake up and feel pain. But they do have some recollection of what happened during surgery.

Although studies show the BIS monitor reduces awareness by 80 percent, there's some disagreement as to its usefulness, so only about one-third of U.S. hospitals use the device.