Matthew Husby, 10, watches a video on the Bedside Entertainment Theater, or BERT. Pediatric anesthesiologists at a California hospital created the device to help distract children before surgery.

Surgery can make anyone anxious, but it is especially hard for young children. Children going into surgery may be separated from their parents for the first time in a frightening new environment, and they may not understand what's happening.

“For many families and kids, this is one of the most stressful events in their entire lives,” said Dr. Sam Rodriguez, an anesthesiologist at the Lucile Packard Children's Hospital Stanford in Palo Alto, Calif.

Panicking before surgery can cause both physical and emotional problems. If children are crying, for example, they're sucking air into their stomachs, which increases the risk that they'll aspirate saliva into their lungs. Anxiety before surgery can also cause long-term psychological distress and behavioral issues.

It is dangerous enough that many children are given an anti-anxiety medication before anesthesia. But medications always carry risks.

So Rodriguez and his co-worker Dr. Thomas Caruso, also an anesthesiologist at Lucile Packard, began tinkering with various pieces of technology that they purchased online.

“My wife gets upset because I'm getting all these packages from camera and tech shops. For a while one of the rooms in our house and whole garage was filled with all these parts,” Rodriguez laughs.

Eventually, they came up with final product: a video unit that they could mount on any hospital bed, that projects an image onto a large infection-compliant screen hooked onto the bed right in front of the patient's eyes.

They called it BERT, short for Bedside Entertainment Theater. It looks high-tech, but the whole thing costs about $900 to build. Lucile Packard now has 10 BERT units across the hospital. They're using it in surgery, of course, but they're also using it to calm kids getting radiation therapy and MRIs.

It is not the only technique Lucile Packard and other hospitals use to help children relax without medicine. Some hospitals give children iPads loaded with games. And there are low-tech approaches, like telling jokes, letting kids decorate their anesthesia masks with stickers, or playing doctor with their stuffed animals. The doctors, nurses and child life specialists at Lucile Packard use all of them, depending on what the particular patient seems to like.

Today Matthew Husby, 10, gets to try out a BERT unit. Matthew has been sick since birth with a rare genetic disorder that affects digestion.

He's used to the surgical process and says he feels calm and prepared. But even this pro still gets some butterflies right before surgery.

When he was younger, the experience was terrifying.

Rodriguez visits Matthew in his pre-op room, wearing a Spiderman surgical cap, and begins explaining how exactly BERT will work. Matthew is excited to pick his own video out of the many options already programmed into the projector unit, including action, sports, cartoons and music videos.

As soon as the video begins, Matthew is completely immersed as Rodriguez unlocks the bed to take him to the operating room.