An ICU Monitor That Fits On Your Wrist

A new medical device wants to make patient vitals more portable and networked, but designing devices for the medical field is nothing like the consumer electronics sector.

Anyone who’s been unfortunate enough to spend time in an ICU knows: It’s a horribly confining experience. Even for patients who are physically capable of walking around, they’re often so tethered to tubes and devices that it’s impossible. Everyone becomes bedbound.


The ViSi Mobile Monitor, by Sotera Wireless, is a pretty exciting prospect in the medical space. About the size of a flip phone, the monitor straps to your wrist to allow patients to move about without unplugging their electronics. It gets measurements from sensors placed on your body, including blood pressure, heart rate, ECG, oxygen saturation, respiration rate, and skin temperature. And just as important, it sends these measurements via Wi-Fi to a nearby nurses station, allowing medical staff to follow an average of eight to 16 patients at once through a PC.

If none of that made sense at all, know this: The ViSi Monitor allows you to go to the bathroom without triggering an alarm that your heart has stopped.

On one hand, the ViSi Monitor has a lot of potential for disruption. It’s portable and networked–two words that aren’t so common in the medical world. On the other hand, it’s no sleek and sexy iPod touch. It’s a clunky little piece of hardware, with a 160×128 pixel screen and an interface that looks inspired by the medical field itself. I wondered, where is the white space? Where is the aluminum and glass? Where is the gorgeous typography? Where are the high-resolution images?

“These guys aren’t cheap, this is something that’s going to live on a person. It has to deal with all sorts of real-life situations no one wants to talk about,” explains Greg Martin, Ziba’s senior interaction designer, who designed the platform’s software. Immediately, I consider the difficulties Jawbone had crafting their Up, while simultaneously having flashbacks to the three people I know who’ve broken their iPhone 5 screens in the past month. It makes sense. But what about that, can I say, sort of ugly display?

“This project wasn’t about innovation, it was about very clear information design in a compacted space,” Martin says. “In the medical space, you’re not innovating for innovation’s sake, which you may be doing on a consumer product. You’re actually looking very carefully on how to maintain the status quo while enhancing the experience.”

In medical design, maintaining the status quo is literally an issue of life and death. When Martin took the project, ViSi handed him a 2.5-inch-thick book of medical device interface requirements, and every page proved important at some point in the project.


Its regulations are rigid. The screen is always black (for low-light rooms). Green always conveys heart rate. Yellow always conveys respiration. Is it aesthetically perfect? Is it organizationally ideal? Maybe not, but these standards reach across geographic and language barriers to allow nurses and doctors showing up in any hospital to instantly understand what they’re looking at.

“When something not calm is happening in a patient’s room, the biggest visual cue that can guide your eyes besides size is color, which kind of makes me curious when I see medical dramas on TV that have machines with purple and blues,” Martin says. “You really start getting into the nuances of information hierarchy.”

Big numbers and bold, set colors–these ideas drive the monitor’s design. But even with strict guidelines in place, user testing was important. And in this regard, there was really only one audience that mattered: the nurses.

“We mocked the interface up in flash and put it on a PDA in front of them. We’d trigger various events and ask them to interpret what they were. Then we’d ask, ‘How’d it work? Is that what your eye is looking out for?’” Martin explains. “It’s something we have an opinion about, but our opinion doesn’t matter, because the nurses are living with it as part of their job.”

The nurses were remarkably precise in their criticisms. Often, points became as granular as how a button blinked when pressed–idiosyncratic design elements that would only strike a cohort of professionals.

With so many predefined boundaries set by regulation and professional preference, building the ViSi Monitor’s interface was the sort of work you can’t possibly approach with an ego. Even still, Martin admits that he would make a few simple design changes to the medical field, if he could–especially in terms of updating icons to have more literal interpretations.


“I’d just bring it up to speed in terms of being modern,” Martin says. “A lot of the icons are fairly esoteric. What they mean today on the devices they’re showing up on don’t mean what they used to.”

Case in point: the symbol during alarms in medicine is a triangle with a line through it–not a bell or something with an analog reference. Martin explained that when the visual was first imagined, this shape actually referred to a specific, physical failure within the hardware of a machine. Now, nurses may still know what it means, but only because they’ve learned the language.

Indeed, from a regulatory standpoint alone, good design in the medical field may never be what it means in the world of consumer electronics. But at the same time, I think we can all sleep a little better knowing that, when a nurse comes to check our vitals on a device like the ViSi Monitor, there won’t be some accelerometer-based physics animation standing in the way.

Currently, the device is going through limited testing in the U.S. and U.K.

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About the author

Mark Wilson is a senior writer at Fast Company. He started, a simple way to give back every day.