Kidney dialysis machines are bulky and expensive, and haven't changed much in decades. But a company called Outset Medical has been working on an upgrade so that someday soon patients will be able to get lifesaving treatment at home rather than at the hospital.

Outset's technology works through a combination of software and sensors that automate the manual steps that are typically required to get a machine up and running. It also purifies water and produces dialysate (one of the fluids used in dialysis) in real time, and it takes a patient's blood pressure. To get it started, the system only needs a electrical outlet and access to water.

All the treatment data it collects gets shared to the company's cloud, making it an attractive technology play as well as a medical device company.

The company's CEO, Leslie Trigg, said she realized before joining Outset that health care wasn't a $3 trillion market. In fact, it's a collection of multimillion- and billion-dollar opportunities. And one lucrative slice is the kidney dialysis segment, which includes software, hardware and services.

The market alone is expected to be worth $22.8 billion by 2022. In the U.S. alone, almost half a million people are dialysis patients, and that number is expected to grow as the population ages. More than 2 million people globally are currently receiving dialysis, according to the National Kidney Foundation.

"It hit me my first week at Outset that this was a huge corner of health-care market," said Trigg in a phone interview. Trigg previously was an executive-in-residence at the investment firm Warburg Pincus. "Nurses were still pushing around these huge machines in hospitals," she said. "We went from that to a 37-inch dialysis clinic on wheels that plugs into any faucet, essentially providing self-service on demand."

That's Outset's device on the left, compared with traditional dialysis equipment on the right: